Identifying mods
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St. Jude Donor '08-'09
Identifying mods
I bought my '91 A4 on December 30th. I don't know much about mods. After reading the thread about being satisfied with stock L98 power, I find that I don't have any of the issues people complain about concerning the L98 being slow. I do know I have flowmasters, 160 degree thermo, K&N and a new chip. Would that make that much a difference or do I probably have mods I can't recognize? Who could recognize them?
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From: OBAMA IS HITLER
nope, they won't much of any difference you can tell. you don't have a baseline to compare it to. out of those mods, only the chip could make a little difference -- and that's only if it's a custom chip (as opposed to cookie cutter rip-off's hypertech, etc.).
its more likely than not that if any real mods were done, that info would have been passed on to you. do you still ahve the shorty factory exhaust manifolds? if you've got long(er) tube headers, that's one clue that more than that may have been done (cam, heads).
so if you're happy, then that's all that matters. me, i wasn't happy and the vette was my first V8 i ever had in 25+ years of driving. was it actually slow? no, but it was alot less than i expected out of the "venerable" corvette. six months was more than i could take, it had to be fixed yesterday rather than tomorrow, if you get the drift.
so that tells you i think stock baseline C4's are inadequate in terms of acceleration, and that certainly goes for the LT1 as well which is in no way off the plate in this discussion.
its more likely than not that if any real mods were done, that info would have been passed on to you. do you still ahve the shorty factory exhaust manifolds? if you've got long(er) tube headers, that's one clue that more than that may have been done (cam, heads).
so if you're happy, then that's all that matters. me, i wasn't happy and the vette was my first V8 i ever had in 25+ years of driving. was it actually slow? no, but it was alot less than i expected out of the "venerable" corvette. six months was more than i could take, it had to be fixed yesterday rather than tomorrow, if you get the drift.
so that tells you i think stock baseline C4's are inadequate in terms of acceleration, and that certainly goes for the LT1 as well which is in no way off the plate in this discussion.
Last edited by Red Tornado; Mar 29, 2007 at 07:31 AM.
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St. Jude Donor '08-'09
I do know that the chip was purchased at The Last detail. A Corvette shop next to a Corvette dealer in Atlanta. I don't know about the exhaust manifolds. I may have to have my mechanic look. I don't know much about what stock looks like. I only know about the minor mods I have due to the receipts still being in the glovebox. I got the car from a dealer. Guess they didn't know that much about it either. People claimed the L98 was weak over 3500 RPM. Mine isn't. I also heard complaints about 40-60 power. Mine will throw you back into the seat(not real hard, but hard enough) when the gas is mashed. Seems to me that there must be some mod I don't know about.
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From: OBAMA IS HITLER
the gages are notoriously inaccurate, so your rpms could be off as much as 500. L98 power drops off significantly at about 4,000 and hits a brick wall at no more than 4,500. what you're describing sounds pretty much stock. i think you'll find out that's the case.
Last edited by Red Tornado; Mar 29, 2007 at 08:32 AM.
Burning Brakes
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From: Ga
i have the same "problem". my 91 l98 auto runs side by side c5s all day. and there is supposed to be 100 pony diff. at the strip they only started to pull on me at about 75mph. so i do think you can have unknown mods when getting the car from a dealer. just my opinion.
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From: OBAMA IS HITLER
if you really want to know, you probably should just get it dynoed. that will help isolate it all to the car.
cost is usally about $50-$80 for 3 passes.
because comparing anyone at the track vs. each other in many cases has more to do with the driver than it does the car.
cost is usally about $50-$80 for 3 passes.
because comparing anyone at the track vs. each other in many cases has more to do with the driver than it does the car.
Last edited by Red Tornado; Mar 29, 2007 at 09:18 AM.
Le Mans Master
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From: Castro Valley Calif.
St. Jude Donor '03 thru '26
if you really want to know, you probably should just get it dynoed. that will help isolate it all to the car.
cost is usally about $50-$80 for 3 passes.
because comparing anyone at the track vs. each other in many cases has more to do with the driver than it does the car.
cost is usally about $50-$80 for 3 passes.
because comparing anyone at the track vs. each other in many cases has more to do with the driver than it does the car.
He's got the fastest car on the forum ya know..........
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St. Jude Donor '08-'09
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
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Would that make that much a difference or do I probably have mods I can't recognize? Who could recognize them?
-is the frisbee gone from the front of the WP pulley?
-does it have the stock front Y w/ the two pre-cats?
-does it have a hi-flow cat?
-does it have underdrive pulleys?
-does it have 1.6:1 RRs (pull the LH valve cover to see)?
-does it have an AFPR?
-does it have 3.07 gears?
-does it have a stock TC (1,500rpm stall)?
-does it have a shift kit (very hard & fast WOT shifts)?
Other than some dyno pulls (to see if any serious internals have been done) take it to the drag strip and record trap speed, ET, air temp, RH and launch weight. From trap speed & launch weight we can calculate CHP, with air temp & RH we can normalize for weather conditions.