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Discussion Starter · #1 ·
Ironed a few things out. Almost kinda difficult to fathom the ET's I managed with how the chassis was set up. Keep in mind this is a "street" cruiser first.

Just removed from the car:

QA1 CO's with 365/465 progressive springs front / CC507 cargo coils rear (these were in there when I bought the car, sat a little high, but never really paid attention to it - actually thought they were the CC501's, finally took the time to measure them. Sure enough CC507's are the 73-77 spec spring. So they're gone). Rear shocks are KYB monotube.


Installed :

Front - 5390 springs (336 rate) w/ 1/2 coil cut for ride height. Lakewood 70/30 shocks (circa 1990 vintage. Still new in the boxes though. As a plus "made in Canada". Long time since I saw something stamped from somewhere other than Mexico or China.

Rear - UMI relocate brackets set to upper hole (2" LCA drop), UMI adjustable uppers and Moroso 47500 rear trick springs. Prior rear compressed spring height was 10". New comressed spring height is a stock '69 spec 8.5". (Both measured without air bags - did not reinstall airbags. So, the tires now tuck up in the wheelwell. I would think the 1.5" drop in the rear alone should help. Shocks are still the KYB monotubes. Car sits level front to back now (28" tires rear / 27.5" tires front). Side to side is level to within 3/16". Pinnion angle set to - 2.5*.

Overall, very satisfied with the test drive today. Drag radials are back on. Car does burn the tires, but two things have definitely changed. Car tracks nice and straight under power. Corners flat (still running 1-1/8" front bar / 7/8" rear bar). Am getting some suspension lift that I definitely didn''t have prior. Think this is important : prior, car would spin the tires (street tires or drag radials) and only leave very light marks. Noticed today, tire marks left are deep black. Guessing this is a good sign that the chassis is loading the tires now. Only questionable item are the KYB's on the rear. They are stiff. Probably good to help control the rate of squat, not so sure they are right if I want to get some lift.

Any input??
 

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sounds like progress, but forget the squat deal, you don't want any. At your power level you want stiff rear shocks to help plant the rear axle. Stiff rear springs for the same reason. A short instant center for the same reason.
 

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Sounds great, like I mentioned earlier to you the Moroso Reat Trick Springs made a huge difference in my car. The best part about the springs you are eliminating the air bag and it still sits level even with the stronger right side spring. I was even impressed with the ride height, it sits the correct stock ride height.

Dave
 

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Discussion Starter · #4 ·
Yeah Dave, really wasn't sure what to expect as to ride height or ride quality. Ride height is excellent. Needless to say, even as firm as it is, ride quality is leaps and bounds over those CC507 cargo coils that were in there. Those things belong on a dump truck!

Will admit, I am amazed at how far things have come. I'm just about running the same ET's with a 3800#, hyd roller cam'd, 275-60/15 DR car with full exhaust as we were with the 5.13 geared bracket car with 13/31 slicks back in the late 70's.
 

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Sounds like you will have a good outing Joe. Good luck!!
 

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Probably tomorrow!!!! Early though. Hoping to get there at 5:00 and be ready to run at 6:00 before all the street cars show up. There's a track rental tomorrow till 4:30, track is supposed to be fully prepped. Barring any spills, it should still be in decent shape early in the night.
I will meet you there. That track owes me an 11 second timeslip.
 

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I think 336 spring rate is too stiff, cut a coil made it worse. The front has to work so the back can do its job. Can you move the car up and down at all grabbing the radiator support?
 

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Discussion Starter · #11 ·
Bob, front end is surprisingly loose. I was worried about going too light up front with the factory AC. This is a full steel body car, bench seat, battery up front. Basically a stock BBC car with alum heads, intake, radiator and headers (my 14GA Hedmans easily weigh as much as stock manifolds.).

Here's all the 11" ride height springs.
#...........ID..........Coil........HT.........Load.......Rate.......Free
5372, 3.63, 0.625, 11, 1843, 288.5, 17.38
5374, 3.63, 0.64, 11, 1957, 317, 17.17
5390, 3.63, 0.656, 11, 1952, 336, 16.63
5386, 3.63, 0.656, 11, 2043, 334, 17
5382, 3.63, 0.656, 11, 2066, 358, 16.75
5400, 3.63, 0.656, 11, 2167, 358, 17.06
5536, 3.63, 0.687, 11, 1984.5, 487, 15.06
And the 11.25/11.50 ride height springs

5380, 3.63, 0.625, 11.25, 1686, 318, 16.55
6330, 3.68, 0.625, 11.25, 1827, 293, 17.5

At some point I should get the front weighed. Went with the 5390 (stock spec spring fopr small block w/ AC or big block w/o AC), but they sat too high. The 1/2 coil came off the bottum, coil was still relatively flat there. Lost about 1/2" compressed ht at the spring, but easily 1" at the wheel. Probably could have went with the 5380 6 banger spring or the 5372. For comparison, I was running a 365/465 progressive coil over which is only a 10" long spring to start with. You're quickly past the 365 rate and into the 465 rate. When I called QA1 prior to pulling the coilovers, they told me no lighter than the straight 350 rate spring for a big block street car. Next one down was the 250 rate. So figured I'd give the 336 a shot.

Walt, no pics. But I'll get some. If you do a search on here, couple threads with pics of '69's with these springs on them. Compressed height is 8.5". Here's what I did prior to buying them to check for tire fit, etc. Drove the front end onto my portable ramps, then jacked up the rear of the car. Put stands under the axle to full load chassis, measured compressed spring height. Then put one set stands under frame, removed rear springs and set another set under the rear at varying heights to see if I was going to like the 8.5" ride height and check for tire fit. Stands rachet at approx 1/2" intervals, so was able to check at 8" ride height all the way through 10". Call it ironic, very favorable geometry at factory 8.5" ride height. Running the UMI uppers, these have a slightly offset rear mounting point. At 8.5" height the uppers are now noticeably angled down at the front. (gonna say a good 10*) At the 10" ride height prior, uppers probably had 15-20* angle up.

Hopefully this works. There's a guy shows up at Cecil - Friday , Wednesday Nights. Drives a mid 70's Buick with a 455, T400 2800 converter, 3.23-3.31 gears . Car runs consistent low 12's. Not a high HP car, but a 4000#+ barge with a torque motor. Turns consistent 1.62-1.64 60' times with 275-50/15 BGF drag radials - regardless of track conditions. Was very willing to share info. Hoping I can duplicate his results out of the hole.

Rich - see you there. Maybe the guy up the street will finish getting his tranny bolted up and make the trip???????????????

PS - if anyone wants the MOOG Spring chart in Excel, let me know. I was able to download it and sort it out by ride height and spring rate.
 

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Discussion Starter · #13 ·
4 runs - results : inconclusive.

Had 60's times: 2.313, 1.660, 2.124, 1.848 (rolled on thethrottle on this run figuring it was gonna spin anyway.)

2nd run was best of the night. 1.660 / 7.416-92.25 / 11.701 - 113.95. Prior best 60' time was a 1.623 back in July before any suspension mods. DR's may be the problem, just not sure. Tried both a hot burnout and a mild burnout, absolutely no concistency. Did notice, with this time out, as I'm doing the burnout, the motor does pull down as the tire heats up and you can definitely feel the chassis load and the car rise. Nail it at the light and your guess is as good as mine. FYI, we swapped the larger 245/252, .651/651 110LSA cam out in August for a tamer 236/244, .610, 112LSA. Liked the bigger cam at the track, but like the better idle of the smaller cam a lot more for general driving around.

So, the jury is out on relocating the IC. Seems to only work if the tires bite. Couple things to try. KYB's need to come off the back for something less firm to allow the relocated lowers to work better and probably another front spring swap to something lower rate. Either the 5372 (1843 load/ 288.5 rate) or the 5380 (1686 load/ 317 rate) should do it. Will have to get the car weighed first.

PS - inconsistency aside, did finish up the night with a great race. Decided to make one more run and pulled a lot of jet out of the carb. Went from 78/86 in the BG800 annular, back to stock 72/80 jets, just to verify the jetting change in terms of MPH. Sure enough, car slowed down, but no big deal, made for a great race. Rich (69BU) lined up in the left lane, my car on the tower side. Knew he was going to hook and cut a light. Figured my only fighting chance was not blow the tires off the line with a little to no throttle until the car was moving. Sure enough, he cut .066 light / 1.812 / 12.148-112.77 to my .432 light / 1.848 / 12.025 - 113.13. Good race. He beat me by a car length. And where was Vince with the video????
 

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Joe- Glad you had some fun. I wish the results would have been better for you after all the work you put in.
I am sure you will find the sweet spot soon.
 

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Joe, you guys swape out cams like it is nothing! I guess you get good at it when you do it alot.

Where the other cars hoking constantly, or were they having promblems too? Could have been the track prep. My 60' times became more constant after I installed HR's anti roll bar.

I hope to go to the track tonight too, if the weather clears out. I'll have my hands full. Justin West wants to race me with his light weight Malibu. Should be fun.
 

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I think I know Justin West ;) lighter?? yeah, but also fewer cubes ;)

Its those front springs, if the front dont work, the back cant work :yes:
 

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And where was Vince with the video?

Sitting here on the beach in 0cean City NJ, not listening to those damn rotary motored cars with you!
 

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Discussion Starter · #18 ·
Yeah Trey, I can swap a cam in about 4-5 hours - in the car. Good thing is, this car's so clean from the resto, can do it without getting dirty.

Bob, absolutely on the springs. I need to get it weighed and go lower rate - for sure. Don't think I want to go all the way down to the Moroso 250 drag springs, but those 288.5 rate 5372's may just be light enough.
 

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I like my Hoosier Quick Time Pros, I run 28X11.50-15 which is approx. 275/60-15. My car will only 60ft in the 1.7* area with M/T ET Street Radials. With the Hoosier's it instantly goes a tenth quicker (1.63-1.65) in the 60ft.

Dave
 
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