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GUS68
09-05-2007, 07:51 PM
Hey guys!!! Been a while since Ive ben on here (life). Anyway, went drag racing this weekend and a freind of mine was there too. We both have simmilar chevelles, same tranny same converter stall, same rear gears, bla bla bla. and he was pulling way better 60ft times than me. we both have slicksans neither one of us would spin. so we got to talking. If my car doesn't spin the rear tires, is it possible to improve the 60ft time with suspension changes? And if so what would help??

wendell
09-06-2007, 05:38 AM
It can be hard to tell if slicks are spinning. Get someone to confirm they're hooking or set up a video of your launch. If you're tires aren't spinning then there's nothing you can do to your suspension to lower your 60' times.

GUS68
09-06-2007, 07:45 PM
Well one freind of mine had a little vidio camera thingy, and we all confirmed that there was no tire spin. Also my buddies watched me a couple of times and all said there was no spin. Yes I have a white line on the slicks. The reason I am wondering about the suspension helping is that my freind with the simmilar chevelle has different shocks and springs front and rear and some other little things, and when his car leaves the front comes up and just barely lifts the front tires and the rear of his car lifts alittle as well. Where as my car seems to lift up equally front and rear but not much. It almost looks like I just drive away, car stays level.

jaybee
09-07-2007, 07:14 AM
Sounds like he has more power. How do your cars compare in the engine bay?

GUS68
09-07-2007, 02:35 PM
Yes I belive he has a little more power than I. We both have 406 small blocks. His heads are better, I belive he has canfeild aluminum heads, not exactly sure which ones, and I know he has a different cam, I just dont know what the specs are. Same compression, I know that. My heads are camel backs that I had ported a few years ago and tested on a flow bench, but I am sure his are better. My buddies 60ft. times were low 1.6's with a best of 1.59, he ran a best of 11.98, and a bunch of 12.0's. My 60ft.s were in the 1.7's with a best of 1.73. I ran a best of 12.57, with mostly 12.60's. I also talked to a guy with a 69 chevelle, with a big block of sme sort, mostly a full bracket car, running 11.50's. he said his 60ft.s were a best of 1.77. All he had done to the suspension was 90/10 shocks in the front, rest was stock. I watched him and his car was not to exciting off the line but did NOT spin.

GUS68
09-08-2007, 06:14 PM
OK, so Iv'e been thinking about it and there has to be something to the suspension that can help 60ft times. Otherwise why is there so much emphsis on it in dragracing and pro touring stuff. Why is there millions of different aftermarket parts and kits for suspension. If all you need is sticky tires, then why spend all the money on the latest high tech suspension part? Just spend all of your money on the biggest fattest gummy tires you can find. if they dont fit just put some spacers in the springs, or some longer shackels on your leafs, or hell, just welt in some pipe from the axel to the frame. Runnin a road corse? Just get the fattest gumballs you can find for the front too. Sorry about the rant it's just that I feel that I'm missing something and I cant seem to find it.

GUS68
09-09-2007, 05:30 PM
Helloooooo.........

Beige
09-09-2007, 08:56 PM
The fat tires thing has been done in both road racing and drag racing.

After traction stops becoming an issue, the large tires are less efficient meaning you're wasting power to turn them. So getting the same traction from smaller tires makes you go faster because you're not wasting power.

Just spitballing some ideas here...

You might be getting traction so well that it's causeing your engine to lug too low in the power band. All of the parts you both share might work better with his engine.
If you had spun slightly, it might not have lugged as much and ran better. If that was the cause of your problems, anyway.

Tolerance stacking might have given your friend a better combination of parts than you ended up with, too.

Norm Peterson
09-10-2007, 04:00 AM
Helloooooo.........Patience, please. Life intervenes, usually on weekends........

The same converter may stall at a slightly different speed depending on the rest of the combination, and may well be effectively "looser" with what your friend has. It isn't a fixed number.


OK, so Iv'e been thinking about it and there has to be something to the suspension that can help 60ft times. Otherwise why is there so much emphsis on it in dragracing and pro touring stuff. Why is there millions of different aftermarket parts and kits for suspension. If all you need is sticky tires, then why spend all the money on the latest high tech suspension part? Just spend all of your money on the biggest fattest gummy tires you can find. if they dont fit just put some spacers in the springs, or some longer shackels on your leafs, or hell, just welt in some pipe from the axel to the frame. Runnin a road corse? Just get the fattest gumballs you can find for the front too. Sorry about the rant it's just that I feel that I'm missing something and I cant seem to find it.60-foot times are much more a dragstrip and maybe pro-street topic than a pro-touring one. But the short answer here seems that if you aren't spinning the tires or wheel-hoppping, chassis tweaks aren't going to be of much help. Sounds much more like a matter of 'area under the torque curve' and how effectively each of you are using what's available.

One other thing - not being a drag racer I'm not sure how this plays out in short times, but were the two of you staging at the same depth?


Norm

wendell
09-10-2007, 08:32 AM
Where's your peak HP and how does it compare to your torque converter stall speed/ rpm you're leaving at? That coupled with traction (you've got traction) determines your 60'.

marty69212
09-10-2007, 09:09 AM
make sure your tires arent spinning on the wheels , my buddy had a huge problem with that on his 79 bue!!!!just a thought !!!!

Norm Peterson
09-10-2007, 09:14 AM
I think I'd be more concerned about where the peak torque was relative to 'advertised stall speed', and on just how similar the engines actually are. Single-plane vs dual, carb specifics, etc.


Norm

JMarsa
09-10-2007, 09:59 AM
I think it's in the engine. I would think that the Canfields would make at least 30+ hp than a ported set of double humps. You said the cam is different as well. Your 60's and 1/4 mile are not that far apart. Again I think it's the heads and cam.

--JMarsa

GUS68
09-10-2007, 07:17 PM
Ok, first off, sorry about the helloooo thing. Bad day, sorry. Any how. I agree, we both guestomated about 30 horse difference. But, like I was saying, I talked to a dude up there with a 69 chevelle bracket car with a big block, which I am pretty sure made more torque than both of us and he had 1.77 60fts. compared to my 1.73s! plus he was running 11.50s, I was in the 12 60s and my budy was running 12.00s with a 1.60 60ft. Now I know this is 3 different combos. But to watch my car and this big block 69 launch, it just looked kinda boring, almost like they just drove away. Now if you watched my friends car the front would come up and slightly pull the front wheels and the back would raise alittle too. The dude with the big block 69 said he had all stock (worn out) suspension except for 90/10 shocks up front. My friend has, what would be conciddered wrong suspension, NAPA stock replacement springs up front with a cut coil, and gas shocks, in the rear he has car quest overload springs with air shocks and an air bag in the right rear, and those edelbrock hop stop bars. I have moroso "trick springs" in front and rear, 90/10 shocks up front, Boxed control arms with poly bushings in the rear and an airbag in the right rear. My converter was made for me and flash stalls at exactly 4500. One thing that may or may not be a problem is I load the car up to 2000rpm on the line, anyhigher and the brakes cant hold it. the slicks cannot spin on the rim becaus ethey are screwed down. I Used to run a 4 speed and I used to dump the clutch anywere between 5500 to 6200 depending on the day. And it would not spin, it used to spin the tire on the rim till I screw them down then I bent all of the studs for the wheels then I bought arp studs, BUT my best 60fts were 1.77 and 1.8s but my et was 12.20s and some 12.teens. Not too far off from my buddy.

MonzaRacer
09-10-2007, 08:17 PM
Well GUS68,
For one your giving up about 100 hp with the Double humps regardless of porting.
You can get about enough air to feed 335 to 340 cubes max out of them.
Been there and done the dyno work.
NOW. The fact he is transfering weight better than you also means his horsepower is makeing it to the ground better.
OK so your only getting less than half of the stall out of your "custom "converter" this is typical and sounds like a hughes but not sure.
IF you asked for a loose foot brake converter you might get it up in the 3000-3500 rpm range with stock brakes.
In all honesty I dumped my rear springs in my 71 Monte and it made a consistent 2.55 60 ft with Sensa tracks, stock 350 with a LT4 HOT roller and a TCI trans and a saturday night special.
For rear suspension I had Southside MAchine bars and boxed uppers nad poly bushings.
I prefer the stock problem solver cargo coils from a 69 Catalina in my Monte for lift but not sure if the 'velle would like them.
In my opinion you need a looser converter or a transbrake.
Ignore the slicks dangit dont worry till you have a problem. Then you can tune the air pressure.
What are your specs on your engine(mods) trans (mods), diff(mods) suspension (mods) pm them to me and give some time to play the numbers and such.
In all honesty give Air Flow Research a call and give them your engine specs less the heads and let them set you up on the heads and you will eat his lunch AFTER you harness the power.
Double humps were NEVER designed for 406s ,heck old 292 Turbo heads took some super major prep work to breath.
I really think your combo can be finessed to work much better but first you need some good heads.
You can spend a $1k on the rear suspension and still have power issues.
If your 60s are consistent and you dont have evidence of wheel spin put your work in your engine combo. OH and after you get the heads you WILL need to recheck your ability to stall that converter (the heads and cam are the brains regardless of the bottom end as long as its built to hold the power level you are attempting to make.
Good Luck
Lee Abel
AFTERMARKET PERFORMANCE