325 BFG DR problem
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Melting Slicks
Joined: Oct 2000
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From: Drag racing junkie Va.
325 BFG DR problem
JP, Mackey or anybody else help!
I just mounted up my new BFG DRs, 325/50/15s on Weld Draglites 15X10, 7.5 BS, 5/16 spacer on my '92 with stock rear spring & HAL shocks. Took it out to go to the track and found that they rub BAD at the top of the wheel well flare :eek: Looked like I was doing a burnout every time I nailed it! Tightened up the shocks all the way to 12 from 5 and it still happened, took all the extra tools & weight out, still no help. I only weight 185, so it's not a fat a** causing this, any ideas?
Has anyone raised their C4 in back by using shorter spring bolts? Anyone know if the 6spd. spring has a higher deflection rate or ride height and did you swap that spring in with the D-44?
Need to correct this nightmare so I can race before I go into withdrawl, I hate being a spectator!
Thanks Dave :confused:
I just mounted up my new BFG DRs, 325/50/15s on Weld Draglites 15X10, 7.5 BS, 5/16 spacer on my '92 with stock rear spring & HAL shocks. Took it out to go to the track and found that they rub BAD at the top of the wheel well flare :eek: Looked like I was doing a burnout every time I nailed it! Tightened up the shocks all the way to 12 from 5 and it still happened, took all the extra tools & weight out, still no help. I only weight 185, so it's not a fat a** causing this, any ideas?
Has anyone raised their C4 in back by using shorter spring bolts? Anyone know if the 6spd. spring has a higher deflection rate or ride height and did you swap that spring in with the D-44?
Need to correct this nightmare so I can race before I go into withdrawl, I hate being a spectator!
Thanks Dave :confused:
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From: Former NCM Drag Racing coordinator, National director Corvette Challenge Spring Hill, Tennessee: Whiting, New Jersey
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Re: 325 BFG DR problem (new92racer)
Try raising the back of the car up about 1/2 inch. It should be OK.
Thread Starter
Melting Slicks
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From: Drag racing junkie Va.
Re: 325 BFG DR problem (mackeyred96)
Mackey,
I must have been reading your mind. I went up to the hardware store and bought two 1/2X8" bolts, replacing the original spring mounting bolts with these raised the rear approx. 1" and cured the problem.
BTW Green Pocket, I tried to remove the spacers, no dice, the wheels still hit the caliper even after more grinding. I know I might be able to grind them down even more and make them fit for now, but with new brake pads I'd be in trouble again.
Let's go racin'!
Dave :D
[Modified by new92racer, 7:14 PM 5/26/2002]
I must have been reading your mind. I went up to the hardware store and bought two 1/2X8" bolts, replacing the original spring mounting bolts with these raised the rear approx. 1" and cured the problem.
BTW Green Pocket, I tried to remove the spacers, no dice, the wheels still hit the caliper even after more grinding. I know I might be able to grind them down even more and make them fit for now, but with new brake pads I'd be in trouble again.
Let's go racin'!
Dave :D
[Modified by new92racer, 7:14 PM 5/26/2002]
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From: Former NCM Drag Racing coordinator, National director Corvette Challenge Spring Hill, Tennessee: Whiting, New Jersey
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Re: 325 BFG DR problem (new92racer)
You'll never fit without the spacers + you may hit the inner frame rail.
I will be looking to go to the smaller brakes.
I will be looking to go to the smaller brakes.
Thread Starter
Melting Slicks
Joined: Oct 2000
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From: Drag racing junkie Va.
Re: 325 BFG DR problem (mackeyred96)
Mackey,
I was at an IHRA event recently and found a C4 Super Stocker in the pits with "Aerospace Engineering " brakes on the front. They looked really well built & light too! I'll check with them, maybe they build the rears to match.
Dave :yesnod:
I was at an IHRA event recently and found a C4 Super Stocker in the pits with "Aerospace Engineering " brakes on the front. They looked really well built & light too! I'll check with them, maybe they build the rears to match.
Dave :yesnod:
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From: Former NCM Drag Racing coordinator, National director Corvette Challenge Spring Hill, Tennessee: Whiting, New Jersey
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Re: 325 BFG DR problem (new92racer)
Mackey,
I was at an IHRA event recently and found a C4 Super Stocker in the pits with "Aerospace Engineering " brakes on the front. They looked really well built & light too! I'll check with them, maybe they build the rears to match.
Dave :yesnod:
I was at an IHRA event recently and found a C4 Super Stocker in the pits with "Aerospace Engineering " brakes on the front. They looked really well built & light too! I'll check with them, maybe they build the rears to match.
Dave :yesnod:
Do you remember who the racer was??????
Class, car Number anything?????
I'd like to talk to him.
Le Mans Master
Joined: Feb 1999
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From: somers, ny
Re: 325 BFG DR problem (mackeyred96)
I had the same problem with them rubbing the fender. two things i did to correct it. First raise the rear; you can get bolts from MAD with more thread area so you can adjust the rear in either direction ($30 with poly bushings). I raised mine about 1 1/2" as the clearance was only about 1 inch when i started with the taller tire. If you raise the rear enough, it will not squat as much on launch, but you'll still have potenital for rubbing the fenders when you hit dips in the road. To stop this, i also added long rubber stoppers in place of the stock ones. The stock stoppers are about 1 1/2", and the ones i've added are conical shaped and about 2 1/2 to 3" long. I also wired back the inner rear of the fender well to stop them from rubbing. Problems solved
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Thread Starter
Melting Slicks
Joined: Oct 2000
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From: Drag racing junkie Va.
Re: 325 BFG DR problem (ralph)
Mackey,
I think I wrote down the guys name with the C4 SS car somewhere, but I can't lay my hands on it right now, but I'll keep looking for it. Phil (wheelsup) & I were in Petersburg at the national event race last month when we saw the car, spent a hour crawling all over the thing. It's a white coupe, no lettering, father-son team, something like a SS/PSA with lotsa' neat tricks, and it went 9.4-9.6s on 10.5" tires!
Ralph,
The tall rubber stoppers you used sound like a great idea for when I loosen the shocks for the drive home, where did you get them? I guess old traction bar snubbers would work, if I can still find them! I'd better check on that inner fender panel on this car, I've already taken them out of the '89.
BTW guys, what's a good starting air pressure for these monsters?
Thanks for the tips guys, if I find out anymore info I'll update ya.
Dave :cheers:
[Modified by new92racer, 9:25 PM 5/27/2002]
I think I wrote down the guys name with the C4 SS car somewhere, but I can't lay my hands on it right now, but I'll keep looking for it. Phil (wheelsup) & I were in Petersburg at the national event race last month when we saw the car, spent a hour crawling all over the thing. It's a white coupe, no lettering, father-son team, something like a SS/PSA with lotsa' neat tricks, and it went 9.4-9.6s on 10.5" tires!
Ralph,
The tall rubber stoppers you used sound like a great idea for when I loosen the shocks for the drive home, where did you get them? I guess old traction bar snubbers would work, if I can still find them! I'd better check on that inner fender panel on this car, I've already taken them out of the '89.
BTW guys, what's a good starting air pressure for these monsters?
Thanks for the tips guys, if I find out anymore info I'll update ya.
Dave :cheers:
[Modified by new92racer, 9:25 PM 5/27/2002]
Le Mans Master
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From: somers, ny
Re: 325 BFG DR problem (new92racer)
I got thew stoppers at CarQuest, but you are right, they look just like the old traction bar stoppers. I've been running them with 18-20 lbs of air, but they might need a little more, cause i've noticed that they are wearing more at the edge than the center. Traction has been great. And you dont have to heat them much on a warm track, but smoke'm good when its cool out.
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From: Former NCM Drag Racing coordinator, National director Corvette Challenge Spring Hill, Tennessee: Whiting, New Jersey
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Re: 325 BFG DR problem (ralph)
I don't thik my next set of tires will be radials????????????????
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Re: 325 BFG DR problem (ralph)
I know what my car will do with the 325 BFGs, so it time to try something else. Maybe a set of Hoosier stocker tires ;)
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From: Former NCM Drag Racing coordinator, National director Corvette Challenge Spring Hill, Tennessee: Whiting, New Jersey
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Re: 325 BFG DR problem (ralph)
ok.....i asked cause mine seem to be working very well. I wish i could say the same about the driver :mad
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From: somers, ny
Re: 325 BFG DR problem (mackeyred96)
ok.....i asked cause mine seem to be working very well. I wish i could say the same about the driver :mad
You've been hanging around Panuzzo to long. ;)
You've been hanging around Panuzzo to long. ;)
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Melting Slicks
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From: Drag racing junkie Va.
Re: 325 BFG DR problem (ralph)
I've got a set of 12.5/28/15 MT ET Streets for the '89 when it's ready, but just in case, I could use them on the '92.
I've been giving the 'taller tire+more gear' a lot of thought, but that will come around with the solid roller. Know of anyone running a C4 with 30" tires now without tubbing? 4:56s?
:yesnod:
I've been giving the 'taller tire+more gear' a lot of thought, but that will come around with the solid roller. Know of anyone running a C4 with 30" tires now without tubbing? 4:56s?
:yesnod:
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Re: 325 BFG DR problem (new92racer)
Me very soon. ;)