My car is super slow
Le Mans Master
Joined: Dec 2006
Posts: 5,139
Likes: 482
From: H-Town Texas
Sounds like your engine is now basically an LT4, the Hot Cam is bigger than the stock LT4 cam. The LT4 came with 28# injectors compared to the, I believe 22# in the LT1. If you're running stock injectors, that might be a starting point. Also look into getting a Dana 44 rear end, this was standard in the manual transmission cars, with the 3:45 rear gears. The automatics got the Dana 32 with I think 3:07? However, the Dana 44 will take bigger gears, like the 3:73 mentioned all the way up to 4:10.
I'm not sure, of course, if any of this has to do with it, but just some food for thought if you haven't already addressed it.
I'm not sure, of course, if any of this has to do with it, but just some food for thought if you haven't already addressed it.
Pro
Joined: Jan 2017
Posts: 702
Likes: 55
From: West Deptford New Jersey
definitely something off there. may car 1993 LT1 ran:
14.2@100 2.1 60' bone stock auto with 2.59 gears
13.2@103 on 1.8 60' after 2800 stall converter, had it dynoed in this trim 270whp
then added cam and 1.6 RR re dynoed results 318whp
and results on pic
Last edited by BLKMAMBA; Oct 24, 2018 at 05:08 AM.
Race Director
Joined: Sep 2001
Posts: 14,685
Likes: 753
From: NEwhere Ohio
Hello, I own a 1992 C4 Corvette with an LT-1 and in my opinion my car is very slow. An average stock c4 corvette with an LT-1 runs a 13 -14 sec 1/4 mile pass.. on my particular vehicle I have made some mods. which are LT4 hot cam kit with heads, 58mm TB, edel brock manifold, hooker headers, borla exhaust, a slight bump up in stock compression, a cold air intake and some very beefy tires in the back, upgraded transsmission with shift kit, custom torque converter for 2500 RPM curve. Not sure what LB injectors I have and I run my 1/4mile no better than a 14 second pass. The take off feels great second gear kicks in with a alot of power but as soon as third gear kicks in my car boggs down.
Any sugesstion on to why my car runs like a stock anything i should check? maybe even a check list of things to check would be appreciated.
#TheGuyWithTheBlackVette
Any sugesstion on to why my car runs like a stock anything i should check? maybe even a check list of things to check would be appreciated.
#TheGuyWithTheBlackVette
you say bogs down.
you mean kind of stutters under load in WOT?
optispark.
this happened on my 93 during drag runs when it had a bad oem optispark (due to water intrusion, cracked seals, and lack of a vent system - corrected on the 95-96 gen 2 models).
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
What was the DA during your races? And what was engine (coolant) temp? If known, what was launch weight?
My best pass at Englishtown was 13.017 sec @105mph with the DA at -1,100'. That's with a 2,000stall TC while making 300chp. On a tight track it pulled mid 1.8s short times.
My best pass at Englishtown was 13.017 sec @105mph with the DA at -1,100'. That's with a 2,000stall TC while making 300chp. On a tight track it pulled mid 1.8s short times.
Le Mans Master
Joined: Aug 2017
Posts: 6,944
Likes: 1,490
From: New Jersey
What was the DA during your races? And what was engine (coolant) temp? If known, what was launch weight?
My best pass at Englishtown was 13.017 sec @105mph with the DA at -1,100'. That's with a 2,000stall TC while making 300chp. On a tight track it pulled mid 1.8s short times.
My best pass at Englishtown was 13.017 sec @105mph with the DA at -1,100'. That's with a 2,000stall TC while making 300chp. On a tight track it pulled mid 1.8s short times.
There is a lot of good data here to check, let us know if you find anything.
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Michael S. Palmer
Team Owner
Joined: Sep 2001
Posts: 62,171
Likes: 1,735
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
I agree, there is a serious issue here.
Check fuel pressure, idle on up through the band, do it in the garage and then take it out with a gauge taped to the windshield on the street.
Check optispark out, get it on a dynojet with a WB and datalog. The curve and the scan data will indicate the problem. Could be the tune is way off base.
If cats are on the car and the previous two check, then I'd guess they are plugged up solid. That will kill the top end you should have now.
Its not the gearing or the tires or anything else, there is a bigger problem to solve.
Check fuel pressure, idle on up through the band, do it in the garage and then take it out with a gauge taped to the windshield on the street.
Check optispark out, get it on a dynojet with a WB and datalog. The curve and the scan data will indicate the problem. Could be the tune is way off base.
If cats are on the car and the previous two check, then I'd guess they are plugged up solid. That will kill the top end you should have now.
Its not the gearing or the tires or anything else, there is a bigger problem to solve.
Last edited by vader86; Oct 24, 2018 at 01:59 PM.
