Tom400CFI

Yet another article, citing the utter domination of the 'Vette in '80's racing.

CORVETTE CHALLENGE

Beating Porsche 29 to 0....yikes.


One thing I've always found interesting is various claims floating around the 'net about the challenge cars' power. 350 hp seems to be a number that I've seen numerous times. 350hp!? Come on. There ain't no 350 hp left on the table in timing, race gas, CAI's and/or port matching. No way. The article confirms what I was thinking. About 1/2 way down:

"These were showroom-stock cars, but optimized for racing. Powell explains that a large number of the Corvette’s L98 Tuned Port Injection 5.7-liter engines were dyno-tested, and only those found to be within a 2.5-percent variance from the L98’s 245-rated horsepower were installed in B9P cars. Engines and transmissions were then “sealed,” meaning that certain fasteners were marked with a special paint that could reveal tampering."

Dyno tested to w/in 2.5% of 245 hp. Wow. That is a looooong way from 350hp claims! There is about 1 way that I can think of, to call a 245hp motor, a 350hp motor; measure it on a dyno using GROSS HP!

...and even that seems like a stretch, at that hp level.

1993C4LT1

Thanks for sharing. And a very good read

3JsVette

Thanks and I agree with your horsepower assessment. Even 350 gross is a stretch.

856SPEED

350 hp would have been a HUGE number back in those days.........(with TPI equipped power trains).

WhiteC1

Interesting article. Just finished reading it. Thanks!

John

QCVette

Good article.

It made me think about people now are stating how poor the C4 handling is.

When you look back at the total domination the C4s had in racing that does not sound like a poor handling car.

Tom400CFI

I don't think the C4's handling is poor now, and I never did. I go faster at autox in my '92, than I could in my '06...and my '92 is totally competitive with C5^'s. On a road course, the C4 is slower...but it's down 100+ hp, so...


IDK why anyone would put down the handling.

84 4+3

Maybe because you actually have to drive it and there aren't a bunch of computers making sure you don't drive into a wall the second you hit a turn... just a thought.

856SPEED

84 4+3

I haven't driven a newer one but from my understanding you can still make them walk out pretty easy. Granted you have a lot more power to help you with that...

73n95

Wanna have some fun? Try a C3 with positraction on a winding road with gravel shoulders. I took a spin, literally with my new to me C3, took a downhill dipper and one tire slid off the pavement onto the gravel, lost traction, power transmitted momentarily to the opposite wheel which also broke traction, put me into a wild 40 mph sideways smokey skid on a narrow country lane that concluded in the opposite lane in the other direction, missing the culvert and boulder but flat spotting my brand new Firestones. Lessons learned.

MatthewMiller

My experience is completely opposite to that, though: the rear end is very stable and puts power down very well. The early C4s maybe have been a little more free for rear traction, given that they had a higher roll center. What I have found is that my C4 is pretty sensitive to rear sway bar size changes, and I'm sure it's also sensitive to rear toe out. So I can see how it would be easy for someone to mess up rear grip with a larger sway bar and/or even the slightest amount of toe out.

MatthewMiller

A few thoughts here. First of all, yeah in the Endurance Championship (pre-Challenge days) it the C4s were racing against 944 Turbos, and it's much more likely that the turbocharged cars were cheating their power levels. As noted, it would be very hard to achieve 350hp with a TPI 350 engine that didn't have a very noticeable lope. Next, it's certain that the Corvette Challenge cars didn't have that kind of power. It was a spec series, so why would they need it? And cheating was pretty easy to catch.

OTOH, the Escort World Challenge cars might be a different story. The rules allowed a little more leeway in the first place - they weren't showroom stock rules anymore. But again, note that some of the types of cars they were competing against (mainly Lotus Esprit Turbos) were turbocharged and probably cheating their power levels a hell of a lot more than the n/a Corvettes. Note that after 1991, the series lost the Escort sponsorship and the Lotus involvement. Also, the LT1 would have been out. It's likely that the 92-96 World Challenge Corvettes had a lot closer to 350hp for real, but those were nothing like the cars that won in the late 1980s or even the 90-91 C4s that won the Escort championships over the Esprits.

Tom400CFI

I recently had a conversation with one of my car-guy friends about the Challenge car 'Vettes. He asked me why didn't 911's race in the Challenge series. I didn't know and thought it was a good question. I initially thought a mid '80's 911 Turbo would give a C4 more of a challenge than the 944T did. Since all my friend does at work is surf the 'net, I told him that he should do some "extensive internet research" and find out.

He did, and his results totally surprised me. First, it doesn't seem that many Porsche 911 were racing in the mid-late '80's. He shared THIS R&T ARTICLE where there appears to be a gaping hole in the '80's. (?)

My friend suggested that the 944 (in the mid '80's) was probably better handling (more benign and predictable) than a 911....he also thought the 911T air cooled engine might not last a long time in racing. IDK. Their air cooled engines seemed to do fine in other types of racing (like Le Mans).

MatthewMiller

The 944s were some of the easiest cars to push hard that have ever been built. You could just hammer on them with any amount harsh inputs and they maintained complete composure. Their Weisach (sp?) rear suspension geometry tended to ensure good rear grip with very gradual limits. I got to autocross one once and I couldn't believe how easy it was to drive fast. The 911s were the exact opposite, although at some point Porsche started working on their rear suspensions too and they got a lot better. I'm not sure when that was - I was thinking early 80s, but it may have been later 80s. I took a friend's 78 or 79 Targa on a run once, and if you lifted at all mid-turn you were toast. That may be part of the reason. The n/a 911s also just weren't very fast back in those days. They had God's own steering, and they could corner well and accelerate hard out of turns, but on any kind of straight I think the Corvette would have whacked them pretty good. And my guess is that the air-cooled 911T of that era was prone to engine problems on multiple hot laps in stock form. Porsche raced heavily turbocharged air-cooled flat sixes for many years in endurance events, but they had lots more cooling and intercooling than the stock 911T came with.

mazdaverx7

I really enjoyed reading that thread! Some very good information in there and the pics are great!

As a 944 owner, I can agree that its a ball to drive hard and has respectable power for the size. Its an all around excellent car. I do enjoy my Corvette a bit more however and feel as though its nice to own one of each as each delivers its own style of performance.