Announcement

Collapse
No announcement yet.

So when does a 'Vette go airborn??

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • So when does a 'Vette go airborn??

    My car has always been a street car with a slant toward the drag race side of things....make that the "street race" side of things. In street stuff....having too much HP can be an advantage so you don't have to relay on perfect traction to get moving. Extra HP allows you to "make it up" a little further down the run if the fist part doesn't go so well. That mentality has always produced cars that go just a little more to the insane side of things....yet remain entirely streetable. This '67 'Vette has made numerous 2000+ mile road trips as well as lot of normal street cruising.

    Over a 20 year period it's gone from a mild smallblock, to a 427, to a 540, to a 555 (871 HP on pump gas). That last version was good for high 9's@142+ mph in the quarter while weighing 3850 lbs. at the line.. Now it's got a 555" with twin Borg Warner turbos on it! The street tune on 91 octane gas made 1140 RWHP...so it's a lot of fun!

    But this is where the problem comes in. It's STUPID to drive on street tires. Every time it hits 3 psi of boost the tires are spinning regardless of speed...and I'm talking at 150+ mph. It took a little while to get the clutch tune dialed in when it was N/A...and it's going to be even tougher with the turbos. They're relatively small and light off quick...so it will be a challenge.

    So my plan is to enter a 1/2 mile event on a runway sponsored by http://wannagofast.com/ at the Sulphur Springs, TX airport. I figure it will give me a chance to bury my foot in it and ensure the engine is happy under full power for longer than a dyno run (which doesn't take long at these power levels). THEN I can go back to working on the dragstrip launches.

    To pull this off...I need to do some preventive maintenance work on some little neglected item as well as reconfigure some things to better suit top end runs vs. drag strip use.

    Here's the punch list:
    • Tires- Need to combine traction with safety. Checking my plain 'ole 275/60 BFG street radials and "tire store" 205/70's.....it appears they have been in place for 10 years. They have lots of tread ( the BFG's just spin...don't seem to ever wear!) and no apparent weathering, but probably time to change them. I've got 15" wheels and really don't want to change them. Not a lot of speed rated 15" tires out there for 15" combos, but from research it appears the typical drag radials do well for the 1/2 mile type events, but the Texas Mile race excludes them.
    • Front Suspension- Over the years it's progressed from stock springs and sway bar, to road race springs and swaybars, to Moroso drag springs with Competition Engineering 90/10 front shocks. So that means the front end comes up easily...and stays that way. Not necessarily a good plan for aerodynamics and handling at speed.
    • Rear Suspension-Consists of a 5 leaf "Daytona" spring with an extra main leaf built by Vette Brakes. Read that as STIFF...perfect for drag racing and really not bad on the street. The rear shocks are QA-1 adjustables. I think we'll be fine here except I need to change out some deteriorating bushings on the end links- their poly and have been there about 20 years.
    • Alignment- 'Vette's act a lot different in the front end than Camaro's and Chevelle's. As the front end rises they "gain" positive camber as opposed to the others that go negative. Great for handling. For drag racing with a lot of front end travel I used a lot of negative camber to allow for the big change as the nose came up. It actually drives OK that way, but I'll take some camber out of it and dial in a whole lot more caster. The rear alignment will be fine as it is.
    • Hardtop-Since my car is a convertible and never came with a hardtop....I've always just raced 1/4 mile with the soft top in place. As you can imagine, they weren't designed for 140-150+ MPH romps and frankly I've been amazed it hasn't torn off yet over the years. It definitely doesn't fit as tight as it once did! I've got a buddy loaning me a hardtop. This will help with aerodynamics and provide at least a modicum of protection.
    • Aerodynamics-The old joke about these C-2 Corvette's is that they have just enough lift to be considered a bad airplane!! And that when they were put in the wind tunnel backwards...they did better!! They also found out in early racing at Lemans that the car handled at speed better when the headlights were opened. Though not aesthetically pleasing....they broke up the airflow enough to reduce the front end lift tendencies. I've always added extensions to the rear hood latches when at the track to kick open the rear side of the hood. Now honestly I did it to allow a 1" spacer to be installed under the carburetor, but also found it helped vent trapped underhood pressure. My car has always handled well at speed up to this point. The '65-'67 Vette's included functional side louvres behind the front wheels to allow air to escape also..so we're good there. I've never been a fan of front spoilers on these cars for appearance reasons, but they DO seem to help....so I'll investigate adding one...at least for this event.
    • Safety- In addition to the new tires, I'm trying to look out for me too...just in case. The car has a strong 6 point rollbar I installed a long time ago as well as a 4 point racing harness. I never added the crotch strap and as long as I have the hardtop (or at least run with the top up) I won't need it per the rules. I'm still going to look into adding it anyway...just need to determine how to attach it properly. I've got my racing jacket, a new pair of racing gloves and I ordered a new full face SNELL rated helmet.
    • Tuning-My plan will be to start out very mild with the boost turned way down. I'm using a Snow water/methanol injection system rather than an intercooler...so it's critical that I keep the intake heat reasonable for the full run. I tuned it on the dyno using -20* windshield washer fluid (about 30% methanol) when I was living in Salt Lake City, UT. Well.....since I moved back to TX, you just don't run to the corner and buy that stuff here and ordering it isn't that easy either. Need to work on that issue. I plan to use some "good" fuel also just to be safe.
    So here's the overall mechanical combination: 555" with turbos, GForce GF5R racing transmission (non overdrive), a custom built Dana 60 IRS with 3.07 rear gears.

    Theoretically:

    6000 RPM = 162 MPH
    6500 RPM= 176 MPH
    7000 RPM= 190 MPH.
    The magical 200 MPH barrier would take 7368 RPM.

    Now while the engine is easily capable of going there....I don't think we'll have enough road to get that far.....plus we're not sure where the aerodynamics will take us...or where my "manhood" will decide to throw in the towel. That's why we're starting with a 1/2 mile vs The Texas Mile...or the Silver State Classic etc. I don't need to prove anything... but I DO like to go fast!!

    Follow along as I detail the updates/changes and whatever issues I run into getting ready. Feel free to offer advice because I've never done this before!!

    JIM











  • #2
    Subscribed!

    Be sure to keep us up to date on how things are going. Never even considered what all might go in to making a run like this.

    Just be safe and have fun!

    Comment


    • #3
      Jim, I would like to see a little more downward rake, not sure you wont rip a front spoiler off at 170 plus, head lights up or down, I don't think le-mans exceeded 160 ish on the straights, and I don't think Daytona vettes made 170,
      So you are a learning curve all on your own IMO, Drag radials work good at speed and road events, but not the 15 inch ones we are accustomed to, to run drag radials at that kind of speed and to have a stiff enough side wall you may have to go at least a 17 inch wheel IMO, surely you have a buddy at mickey Thompson to advise on this,

      IMO, don't do the hero run first pass (like your prone to do) sneak up on it a little I think 160 will be fine, but I would really like to see you sneek up on it in 10mph increments, and yeah with your gears, you have enough power to prove the math you have done with no problem. STAY SAFE!!!!! on this one buddy, there are a lot of things that could jump up and bite on this one!!!

      Comment


      • #4
        So Jim, 1st off at that speed, I would think you would need a full cage. 2nd, most of the cars that is see on video seam to loose the rear end. You need front AND rear downforce. Upgrade your belt, WITH a crouch strap. Inch up on the speed. DON'T BE STUPID!!!!. This stuff is WAY serious. I want you as a friend for a LONG time. That said, How cool would it be to see a stock 73 pick up do about 150 on a 1/2 mile? LOL

        Comment


        • #5
          They've still got a couple of open spots on Sunday!!

          JIM

          Comment


          • #6
            The first mod to make was to change the upper control arms to allow for greater caster which increases straightline stability at speed. Tires have come a long way since the 60's and though these cars were cutting edge in their day (and still pretty darn good today), radial tires along with stickier compounds allow us to do things they never dreamed of back then. My car has a Borgeson power steering kit installed on it with a quick ratio box that really prefers extra caster as compared to the manual arrangement for increased road feel. In addition, my car sits pretty low in the front which tends to increase "negative camber" (wheels tipped inward at the top)...so having offset shafts will push them back outwards a little to give me some latitude when performing the alignment.

            Many folks modify their upper control arm shafts by elongating the frame-to-arm mounting bolt holes to allow the upper control arm to be slid rearward...which quickly increases caster. To keep the arms from slipping, some folks make a "plug" to make up the extra space in the elongated hole...but it's not absolutely necessary.This has been done for years and will definitely work, but I decided to just replace the arms with a better design.

            My old arms had been rebuilt years ago with new ball joints and polyurethane bushings...and were sill in good shape...but the new arms bring all new stuff to the table. The lower ball joints, bushings and arms were inspected and all was OK.

            Once I get everything else buttoned together with the front springs and shocks....we'll go into details on doing "home alignment" with some really nice and simple to use tools.

            With the upper arms in place, it's time to move along to the next areas to get this thing ready!!

            JIM


            The new upper control arms (Part# 42102) from Vette Brakes are sweet. These are the newer design that are lighter than their original box tube style and are 2.5 lbs lighter than the stockers. I ordered the ones with the upper shafts made of steel...but there's also an aluminum shaft version.




            The beauty of these is the increased built in caster angles. These allow you to get at least 5* caster whereas the stockers have a heck of a time getting to 2.5*. Take a look at the re-positioned upper ball joint that places the upper part of spindle further rearward...which is what makes positive caster.




            Another advantage that cones with these arms is the "offset" upper cross-shaft. This allows you to move the entire upper arm either inward or outward to add or subtract a lot of camber as needed. As you add positive caster, you tend to increase negative camber...sometimes more than you want. Also, over the years, old cars tend to spread a little in the frame and control arms. This causes negative camber...so the offset arms allow you to put things back in the general area they should be so you can make the final adjustments using shims. If you remove all the shims and you still have too much negative camber, you need offset shafts. You don't have to buy a complete set of aftermarket arms to get the offset upper shafts....the shafts are available individually to install in your original arms. It's a little hard to tell in this picture, but the machined flat spots on the arms are offset "thicker" on one side than the other to move the whole arm in/out.




            Installation is really straightforward and one of the easiest mods you can make. Swapping the arms requires separating the upper ball joint with the ball-joint fork while supporting the vehicle's weight on the lower arm. This holds everything in place.. Remove the nuts holding the upper cross-shaft to the frame mount. No real need to keep up with where the shims are located now...they won't really mean much with the new re-positioned arms in place. Just slip the arms off the bolts....you might have to tap the bolts back out of the frame mount to allow the arm to come off depending on what's in the way (like headers etc). Slip the new arm in place while paying attention to the stampings on the shafts/arms that indicate which one goes on right or left and which way the upper shaft should be positioned for the camber changes discussed above. VB starts with them pulled "inward", but they can be flipped as needed to add positive camber.




            Last edited by 540Hotrod; 10-20-2016, 09:34 PM.

            Comment


            • #7
              im liking the ability to get the caster and camber dialed in, that ability was already used up on most muscle cars by 78 and 79, remember how we used to try and spread the frame rails on chevelles to be able to align em??

              Also I was thinking, are you going to attach a G-tech or some other device to the windshield at eye level to monitor speed for yourself??

              Comment


              • C5rider
                C5rider commented
                Editing a comment
                Now, THAT's a good idea. I've got one that I'll donate to the cause if no one has anything any closer to you. That said, will a G-tech measure for the full 1/2-mile? I'll have to dig out the box and see what's available in that thing.

                thoughts?

            • #8
              On the issue of tires.....I definitely needed to do some work. As mentioned, my old BFG street radials and generic "tire store" Tempest brand front tires were 10 years old. They've really worn well actually. They've been on cross country road trips and more 130 MPH-150+MPH blasts than I probably ought to admit to. The BFG's spin a lot.....they don't really smoke anymore...or even leave black marks....they just spin. Any application of throttle results in instant wheelspin and an "ice skating" feeling. Both front and rear tires were chosen more for aesthetics and size to fill the fenders than performance....and for general riding around were just fine.

              I wanted to stay with 15" to eliminate the need to buy new wheels...but more importantly I wanted to keep the 28" height of the 275/60 size tire. Since I don't have O/D, I can't afford to give up 2"-3" in tire height which would have a drastic impact on final effective gearing. I would have gone to a 29"-30" tall 295 or 305 series if I could have stuffed them under there without jacking the rear too high.

              I did a lot of research trying to find tires suitable for a high speed run as well as able to provide at least a modicum of traction to get me moving. With "only" a half-mile to get up to speed....I need the ability to apply as much power as possible without sliding around.

              While a lot of drag racers have a hard time launching a heavy stick car on drag radials of any kind....this wasn't really a drag strip style launch. I need to roll into the throttle as quick as possible. I've got Mickey Thompson 28"x10.5" racing slicks for the dragstrip....but I wasn't sure I wanted to make a set of slicks go a half mile. I also have a set of Mickey Thompson "front runner" race tires (these and the slicks are mounted on some light M/T and Bogart racing wheels)...but when I looked at them...they were a little aged too.

              The choices in 15" rear tires narrowed down to Mickey Thompson, BFG, Hoosier,Nitto,and M&H. Obviously everyone has a different car and different conditions, so it's tough to narrow down anecdotal stories of one being better than the other. At the end of the day I went with the Mickey's primarily because they've been proven for years and I've had a chance to drive a set of them on my buddy's 800 HP '67 'Vette even though those are 255/60's which can only do better in a 275/60 size. There's several versions of M/T DOT drag radials. One is a pure race tire really not designed for any street use. Then there's the 'R" series....a drag tire with just enough tread to be called street legal. Next is the "SS" series. Same "R2" rubber compound for traction as the bad boy race tires, but with more tread design. Since I intend to leave these tires in place for normal street use after this event, I selected these...part # 3453 in the 275/60R15 size.

              The front tires were even more problematic. I wanted to find something to fit my 15" x 4.5" front Cragar wheels as well as be somewhat "speed rated". Turns out there aren't a lot of choices there either! The 'Vette is pretty heavy compared to most cars that would run tires this size so I didn't really want to drop much below my current 205/70R15 size. If I went down to 195/65's I found a few V (149 MPH) and a Pirelli W (168 MPH). I also chased down some high $$$ AVON tires...but couldn't find any in the USA or able to get them shipped in within time. The only choice past that was in the 205/65R15 size and those boiled down to some Kumho's, with a V rating. Now certainly there's a good chance we'll exceed that speed for a couple of seconds....but remember...those ratings are for "sustained" speeds. I feel MUCH more confident with these than what I've been using for sure!

              Once the tires arrived, I took them to my local Goodyear store to have mounted/balanced. I spent a little time telling them exactly what I was planning to do and they took the extra time to move the tires around on the rim to require the least amount of weight. It was interesting watching the regular mounting guy work with the drag radials and getting a little frustrated trying to hit the balance perfect. Everyone was offering advice and then finally the "tenured" guy who's been doing it for years and had some serious "tribal knowledge" came up and determined that if we "removed" a little weight on the correct end of the "tape weight" rather than "adding" the extra weight the Snap-On balancing machine was asking for...the tires balanced perfectly. The fronts were easy enough to balance with no drama.

              I loaded everything up and took them home. Before installing, I added some "Gorilla" tape over the weights. This isn't so much to keep them in place...rotational force will do that.....but I've always done this to protect them when installing in case they get bumped.

              I replaced some old bushings under the rear spring ends and the rear is a little high in this pic. I'll lower it down once we get to the final "dial in" stages of the alignment. Here you're getting a "teaser" shot of the QuikTrick alignment system I'm using.

              One more item checked off!!

              JIM








              Last edited by 540Hotrod; 10-23-2016, 10:34 AM.

              Comment


              • #9
                Too bad they won`t fit my Nova , I think they would frown on my VW front tires..
                Every thing is going too fast and not fast enough. . Warren Oats a.k.a.."GTO" Two lane Blacktop..

                Comment


                • #10
                  They make 255's.........they'll hold it.

                  I've got some extra 205/70's for you....

                  JIM

                  Comment


                  • #11
                    well tell me about the align ment? 0 camber, 4.75 caster drivers side 5.0 pass side, 1/32 toe ?

                    Comment


                    • #12
                      Pretty darn close!!! You're good!! You'd think you'd done a few of these before!!

                      I've actually got a little over 1.0* camber. 'Vette's go "positive" camber as the nose rises....so they act opposite than Camaro's etc. I like how you think on Caster.......cars will "pull" to the side with the least caster...so having a little less on drivers side helps correct for road crown. Of course camber is opposite of that...it will pull to the side with the most camber...but not as noticeable as caster. Caster can do a lot of good and bad things!

                      Plan on getting it out for some "test runs" this weekend to see how it handles.

                      More to come!!

                      JIM

                      Comment


                      • Rtanner
                        Rtanner commented
                        Editing a comment
                        Damn I certainly enjoy conversations with a guy I can be on the same page as!!!! you are the only guy in 25 years that I can I have an intelligent, front end alignment conversation with!!!

                    • #13
                      The next step was to do something about my "drag race" front end setup. I've been running Moroso Drag Race springs on the front end and Competition Engineering 90/10 front shocks. The combo made a DRAMATIC change in how the car launched at the track. The front would rise perfectly and plant the rear tires for a nice wheels up launch. I've driven this arrangement for years and have become accustomed to how it handled...if you could call it that. Even on street tires...the front end lift was tremendous and the shocks would delay the return to normal. Great for drag racing...not so good for handling. For example...let's say you're driving a little "spirited" and the front end is high and all is going well...right up until something jumps out or pulls out in front of you. You lift and get on the brakes....problem is the nose doesn't come down and there is minimal weight on the front tires. They don't respond to steering wheel input and next thing you know you're in severe understeer and cranking on the wheel and getting zilch!. Not a good plan if your course needs corrected suddenly!

                      I was also able to drive a buddy's '67 Vette recently which has an 800 HP 548" engine. Definitely no slouch. His car is equipped with 750 lb. front springs and it was really neat to get to drive something which actually enjoyed going around a corner!!

                      One choice was to reinstall my 550 LB springs from past days. They handled great...but they also drop the front end a couple of inches. I can only go so low on this thing...I've got a huge drag race style oil pan (works great when cornering/braking also) and a 3.5" exhaust system. If set too low....I scrape the pipes pretty easily...and since they are bolted to some pretty pricey turbochargers, I sorta hate to bang them solid on the pavement too often.

                      I could also install an old set of small block springs I have, but with the weight of the big block and the turbos up front, the front end height could be an issue again.

                      So I started looking around for something that would allow me to set the front end height as well as exercise full control over the compression/rebound cycles of the shock absorbers.

                      A couple of years ago I spent some time in the Viking Performance booth at SEMA and drooled on all their innovative products. http://vi-king.com/ so I decided to dig through their catalog and refresh my memory of whether they offered anything for a C2 Corvette.

                      Well...it didn't take long...there it was...right there on page 22. Part number A324AP-350PK is a coil over shock kit designed to provide a stock ride height to a 2" drop on smallblock and big block cars. There is also another version that allows up to a 3" drop. The "Crusader" series offers 19 adjustment positions for compression and 22 positions for rebound. This along with the correct spring combination covers Pro-Touring, small tire drag racing as well as mega-HP drag racing setups. That's a pretty darn wide range of adjustment! The spring rate is 350 LB's/inch which we discussed "might" be a little light for maximum handling of my car considering the front end weight, but I reminded them that I'm using 205/65x15's on the front end....so tire grip is limited. I still want to have the ability to launch hard at the track (which these will do) and these are a LOT different than the old 212# drag springs I was running!!

                      When the kit arrived....I couldn't resist laying them out to eyeball the "jewelry"!! Wow.....that's almost too pretty to put under the car!! You can see that everything you need is included.




                      The first step is to pre-assemble the adjuster and lock nut as well as the bearing assemblies onto the shock absorber. The instructions stress the need to coat the threads with anti-seize to avoid galling the threads. This is aluminum on aluminum...so protection is necessary. You'll also want to coat the roller bearing needles and washers that the springs ride on.




                      I won't go into all the details of separating the lower ball joint and removing the spring assembly here. Refer to a normal repair manual for the steps. It's not a hard job at all, but you must do it correctly to be safe. The spring has the potential to do serious harm to your body, so you want to do it correctly. Again, not hard to do at home with the only special tool being a "ball joint fork" that can be purchased or borrowed at the local parts store. You can actually do it with a little judicious hammer tapping on the side of the spindle where the ball joint slips into the spindle, but the tool is quicker and easier for me.

                      Here's a comparison of what's coming out and what's going in. Notice the drag race spring is made of tightly wound wire and is very long. This compresses a lot when at rest with a lot of stored energy just waiting to be released as the car launches, The Viking Crusaders will allow height adjustment as well as easy, infinite shock adjustments.




                      The new shock assembly attaches to the control arm with 3/8" bolts. The problem is that every old Chevy I've ever dealt with has 5/16" bolts holding the shock in place. There are nuts tack welded to the control arm which can be removed, but I decided to just drill them out to 3/8". I liked the idea of leaving them in place as extra reinforcement for the control arm. The next step is to assemble the shock assembly to the control arm while ensuring the adjuster knobs are positioned "outboard". You slip the mounting "tab" down from the top...which takes a little wiggling but it fits. The instructions note that there are lots of variations in production control arms tolerances over the years, so after attaching the shock absorber to the control arm, ensure it can move freely through it's entire range of motion at the shock/arm connection. In my case, when I moved the upper stud of the shock to align with the upper mount, I found the larger body of the shock contacted the inner side of the control arm opening on the inboard side. A minute with a die grinder relieved about a 1/16th of an inch in the affected area with a little contouring. With those slight mods, everything was ready to bolt together.



                      With the shock bolted in place, it's time to assemble the spring. The instructions tell you to run the adjuster nuts about 1/3 of the way up the shock for a baseline. Now just slip the spring over the shock body (small end first) and then rotate the spring to align the end of the upper part of coil with the spring pocket in the frame. You can reach up inside the frame and feel where the end of the coil should be. Make sure you've installed the first washer/bushing on the upper stud and align the upper stud as you use the jack to slowly raise the lower arm to re-attach the lower ball joint to the spindle. Install the upper nut and washer/bushing and you're done with the hard part!

                      In my case, I took a SWAG (scientific wild a$$ guess) and set the adjusters at 1.5" up from the bottom. I wanted to raise the car approximately 1.5" from where it was with the drag springs which had been originally trimmed by 3/4 of a coil...but with about 12-13 years of street and race use, they had settled somewhat. The two measurements have no relation other than coincidence, but when I lowered it to the ground I was just under 2" higher. Every car will be different. Mine is a big block with an aftermarket block, stock radiator, P/S etc. and two turbochargers sitting right behind the front wheels...but at least this will give you a baseline to start with to think through your combination of engine, A/C and other components.

                      One CRITICAL item. NEVER attempt to adjust the spring height with the weight of the car on them. You must raise the car so the control arms are hanging loose. To adjust, just use the included spanner wrenches and lock down the adjuster nut when you're finished.



                      The instructions include a myriad of baseline shock adjustment settings based on your intended usage. It's easiest to make the initial setup before installing everything.




                      Now it's time to repeat everything on the other side (which always goes much faster!), You'll want to inspect everything closely to ensure nothing is forgotten or if there is any contact where there shouldn't be. Next, bolt the wheels back on and lower it to the ground. Bounce the car a few times and listen for any unusual noises. Crawl underneath and once again look at everything to ensure everything is in place as it should be. Once you're satisfied, it's time to take your first drive to experience what real control is!! The difference for me was amazing of course....but I can guarantee you'll also recognize the huge difference immediately. After you've driven it some, try different shock settings by adjusting either compression or rebound (or both) to establish what does what on YOUR car and how YOU like it to feel.

                      Stay tuned as we continue to prepare for this fun run!


                      JIM
                      Last edited by 540Hotrod; 10-26-2016, 03:13 AM.

                      Comment


                      • #14
                        Great write-up. Will be VERY interesting to see how the new shocks/springs perform compared to the old set, and also how much of a spectrum the adjustability will provide once dialed-in. Amazing how this racy-race stuff has migrated onto the street and allows for performance AND drivability! Let us know your thoughts once you've had a few miles on them!

                        Comment


                        • #15
                          Well...it's been a busy week since the last update.

                          First thing is I wasn't "quite" finished with the Viking coil over package like I thought. Upon closer examination I found the upper shock bodies were contacting where it extends up through the frame hole on the way to the upper shock mount. Hmmnnn....really didn't want to tear it all apart....and I found that if I raised the car and le the suspension droop with the upper shock mount disconnected....I could reach in there from the engine compartment side and use an extended burr on my air grinder to open the hole some more on the inboard side (same as below). Really didn't take long....but was a little bit of a PITA.

                          Once it was all together and I drove it a few miles to let everything settle in place, I found the front was higher than I liked. So scratch that 1.5" baseline measurement....I ended up with 3/4" from the top of the lock ring when it was screwed all the way down. This placed the fender lips 24" from the ground when measured at the centerline of the wheel.

                          Last week I had decided to do some preventive checking of things to make sure all systems were a "go". I've got two Aeromotive A-1000 fuel pumps under the rear of my car. One runs all the time and the other is switched on when I want to go into "FUN MODE". While the A-1000's are great pumps, one alone isn't able to keep up under boost with EFI type fuel pressures. Anyway, I decided to isolate the two pumps and measure their output one at a time. Guess what? I found that the 2nd pump was locked up!! You could hear it humming..and the volt gauge showed it pulling current....but there was NADA coming out of it! Glad I checked it before I went racing!!

                          I disassembled the pump to see what might have happened and found a small sliver of something had wedged itself into the pump assembly. The motor ran fine, but the pump part was damaged. I decided to just order a new pump...I've had that one for about 15+ years...so it's served me well. I can send to Aeromotive for a rebuild and keep for a spare. Swapping in the new pump got everything back on-line and working perfectly! Dodged a bullet there...would have hated to find out I was running out of fuel somewhere between the 1/4 and 1/2 mile mark....and finish the run with a few less pistons than I started with. Time to turn on some more protection parameters in the 'ole Holley Dominator EFI system just in case!

                          JIM

                          Comment

                          Working...
                          X