Pros and Cons of ZR1 ownership

[pologreenvette]

Originally Posted by mike100

I think the 440 hp run was with headers. A lot of the dyno plots I've seen that power peak at that high of an rpm have different pipes. The early cars power peak near 5900 rpm with the stock cams and exhaust manifolds.

Easy gains though..and one I still don't have due to CA emissions law.

That is some very easy gains, just headers getting 40hp? Are there any other relatively easy mods for the ZR1?

Originally Posted by LancePearson

calling you? Heck, I already own one corvette and bought the z as a second one when I started dealing with the engine I discovered when thinking about changing the 76 to a c5. You know they ran a z March 1=2, 1990 with a 3:07 rear end for 24 hours in Texas on a tire 7.7 mile test track with driver changes, tires and fuel every 80 minutes or so all night long.
They ran the car at 5500 rpms in fifth gear and averaged 190 on the straights, curves sapped down to 174 or so then back up for 24 hours with stops as above. Old record: 161 mph. Their record: 175.885 mph.
the car is in the NCM in Bowling green. The red car on the right is the one that set the record.
the other was a car with an l98 they tested which had been used in europe on other tests.

It's also where
goodyear spent $250,000 developing what we know of as the goodyear eagle f1 high speed tire to do the test. No track lights on what is now bridgestone's tire test track at Stockton, Texas.

Flat out shift points for mine are third top about 120 then fourth top about 145 then fifth? fifth is .75 to 1 and sixth is .5 to 1 ratio overdrive.

And, to make it better yet, driving the Z home from Atlanta area where I bought it I did one 100 mile stretch on I 85 at 73 mph in sixth gear and got 29.1 mpg.

The entire 515 mile drive home was 26.8 average including drives off the interstate to a motel, dinner, gas stop, pit stops. Hard to find much better package.

Everybody here will tell you this: when you first hop on it hard, all the way hard, you have to remember to breath.

Photo of the actual car attached.

I've read all about the record, that's truly incredible. What a testament to how reliable the LT5 is, not many engines could handle that.
That sixth gear is awesome, I get 30mpg highway with my car all the time! I'm still in shock about your shift points, is your car stock? Does it have 3.42 gears?
I'm not sure if I could even breath, the acceleration may cave in my rib cage...

[mike100]

Originally Posted by pologreenvette

That is some very easy gains, just headers getting 40hp? Are there any other relatively easy mods for the ZR1?

I suspect that was with minimal to no mufflers, no cats, and an optimized chip on the engine dyno. But pretty much everybody has a chip and a cat-back- you might have a hard time finding a ZR without that stuff.

I don't think it was mentioned, but buying a modified car will save you a lot of $$ since the stuff for these cars is a little expensive compared to a SBC.

ON EDIT: The later 405hp cars had improved intake ports and a little bit more intake cam duration, but it is very common to port out the plenum and intake runners on the early cars too. this adds more hp to the 375 hp cars than the 405 hp ones I did it to mine- just need the headers to cap it off.

[LancePearson]

Yes, my car, 1991 0682, is stock. However, calling it 375 hp appears to be wrong. The dyno tests done that they selected that from picked much lower rpms than it runs. With one or two very minor things done to it, the correct range of hp at higher rpms it is more like 440-450 hp at the flywheel and about 15% less at the rear end. I can assure you that it is more powerful than my 2008 LS2 of about 410 hp based on driving the two. This engine is often referred to as a "beast" and it is, just keeps pulling and pulling. You have to drive one to experience it but they really fly. Tuned with top end, headers, etc. you can get them up to 198 or 202 mph on the right roads.

To answer your question mine has the stock factory 3:45 rear end which is a fair combo for quick acceleration and highway combined with the .5 to 1 sixth gear in the robust ZF six speed tranny. I have not found a road where I can let it out well into fourth gear much less fifth though they are big gears that you can drive at much lower speeds and narrower ranges. Turn it on, however, and hold on because it is going to sound special and leave the borla's exhaust sound way behind. As it is when I've let it out into low three figure speeds I'd be going 65 mph over as is and in Va. that's beyond reckless driving if John Law is around.

Your question: "I've read all about the record, that's truly incredible. What a testament to how reliable the LT5 is, not many engines could handle that.
That sixth gear is awesome, I get 30mpg highway with my car all the time! I'm still in shock about your shift points, is your car stock? Does it have 3.42 gears?
I'm not sure if I could even breath, the acceleration may cave in my rib cage...[/QUOTE]