Corbusa

New guy here.. I'm looking at getting a friends 1990 zr1 . I'd like your opinion on the longivity of the engine/ is it durable? I mean I dont want a money pit where every day something is breaking,, example : he had to replace the computer .That makes me ask why at 34k miles is the computer bad. So how do you guys feel about the zr1. Hows the C4 compare to the C5?
Does anyone have or make a procharger for the 1990's zr1's ?
Does the zr1 have any issues that I need to be aware of? ( Like some cars are known to have trans. trouble straight out the factory or leaking head gaskets etc .. what can I expect to deal with? Thanks and I appreciate the help...

zr-1 guy

Although the ZR-1 was extremely quick (0-60 mph in 4.4 seconds, and onto 180+ mph), the huge performance of the LT5 engine was matched by its robustness. As evidence of this, a stock ZR-1 set a number of international and world records at a test track in Fort Stockton, Texas on March 1, 1990, verified by the FIA (Fédération Internationale de l'Automobile), including seven new international records:

* 100 miles (160 km) at 175.600 mph (282.601 km/h)
* 500 miles (800 km) at 175.503 mph (282.445 km/h)
* 1,000 miles (1,600 km) at 174.428 mph (280.715 km/h)
* 5,000 km (3,100 mi) at 175.710 mph (282.778 km/h) (World Record)
* 5,000 miles (8,000 km) at 173.791 mph (279.690 km/h) (World Record)
* 12 Hours Endurance at 175.523 mph (282.477 km/h)
* 24 Hours Endurance at 175.885 mph (283.059 km/h) for 4,221.256 miles (6,793.453 km) (World Record)

the lt5 was designed to go 250,000 miles without a rebuild. it was run from peak torque to peak hp and back again in 5 minute increments for 24 hrs. the lt5 is as bullet proof as it comes. why did the computer fail? i couldn't begin to guess.

as for the procharger there was a rumbling that someone made a prototype one, dunno if it ever came to production...I may have a picture kicking around my hard drive. The zr-1 has the normal c4 problems like they all do but the zr-1 specific stuff is rock solid. as for how they compare to the c5...well the c5 is easier to get in and out of, easier to mod, and easier to find. the only zr-1 specific problem i can think of is that it wears out rear tires faster then fronts...i keep meaning to have it looked at but i never want to stop driving it.

these cars love to be driven, hard, and often.

C4Fanatic

The only issue with mine is the fact I can't get the grin off my face for several hours after I get out of it.

And the thought of a ProCharger just scares the jeebeees outta me...I got more than enough at the wheels to keep me happy.

Rkreigh

the engine isn't a problem on the zr-1 early cars suffer from injectors that die running alchy formulated gas, and changing plug wires and maintaining vacuum systems which scares ham fisted mechanics because you have to pull the plenum a 30 min job

lt5 will run like a scalded dog and is as durable as an anvil

I have put 200k miles on various zr1s and never had any engine problems at all. my current lt5 "stroker" has 80k miles and pulls 619 hp (508 at tires)

it's a very expensive engine to modify, but basic mods like headers, chip and porting the intake will easily reward you with approx 400 very reliable hp at the tire. want more, get ready to spend

see zr1 net registry to see everything you ever wanted to know

Corbusa

Thanks for the info.. It is appreciated and thats great numbers on the lt5, can you send me some specs on what you have in it?

Paul Workman

Here is a picture you will like. It is a 5.7 stock bottom LT5 with stock cams that has been fully ported and has headers and tune. Going to need to bump the rev limiter to about 7400 rpm to take full measure of what it has to offer!









The LT5 in stock form is just dying for more air! The mods you see put my stock bottom 5.7, stock cammed LT5 at...well, you too can read the numbers for yourself!

Best car/engine I ever had anything to do with...Ever!

P.

zr1fred

I can't think of any major LT5 problems, most of the problems are common to C4s and age related (generic and geriatric ) I don't know why his computer was replaced, but very often problems are mis-diagnosed as computer problems.

Dominic Sorresso

You can have a stock block LT-5 with over 500hp with just a ported top end and heads + intake cams. Don't really need forced induction for that kind of power.

Corbusa

Cool, I like it !! are there manuals available for the engine? I have rebuilt a few small blocks in my day and a few automatic trans, Is the LT5 easy?

Corbusa

Guys If all works out ( and I'm hoping it will) I'll be here on the forums for quite a while.. and your helping me with info. If I can return the favor let me know. I can hook you up with Sniper scopes and Tac. Gear. ( I dont mean to sound like i'm advertising-) Just one hand washing another... I do appreciate the help and I like pictures . Paul Workman Did you do the porting yourself? Porting the heads and intake?

zr-1 guy

if you get the car make sure you join the registry www.zr1netregistry.com

glass slipper

Just a minor correction, the durability test you described was run for 400 hours...yes, the LT5 is bullet proof. I've beat the crap out of mine for over 18 years on the track with zero problems.

Coupe89

Manuals only from the factory. There are a few people that converted to an Auto....

Paul Workman

Yes, I did. I relied heavily on this guy's (Pete) model and that of Marc Haibeck, another name you'll get to know once you join the Brotherhood of the ZR-1.

See if this example of Pete's LT5 doesn't get your blood circulating!

http://www.youtube.com/watch?v=SFNFOhGGlR4

Pete's down to 11.04 now, looking to get into the 10s with his stock bottom 350 cid, ported and cammed LT5. (Pete and some other gurus reside on the Registry).

Your only regret will be waiting!!

P.

Corbusa

YEA That got the blood moving !! Heres what I'm doing .. I am awaiting some paper work for some out of out of area work.. All should be ok. But I dont count anything until I know for sure. As soon as I know I have the all clear , I'll get the vette.. I dont do the debt thing unless I know I can pay it off very quickly.. In the mean time I am working Lots of side jobs ( more than I can handle) and finishing my studies and getting the house up to par so it wont have any maintence issues for a while..

zr-1 guy

crap you're right. dunno where 24 came from...must have been the records

Z51JEFF

Id have to agree,it seems the first part to replace seems to be the computer when a shop runs out of ideas.

Zerski

WOW! Can I get a link to that? or more info?

Paul Workman

Best source on that testing and much more on the development and all things ZR-1 are in the book, "Heart of the Beast". It is a facinating read, whether or not you are a owner of The Beast or not!

P.

glass slipper

The 400 hour test is an extreme performance/endurance test. It involves running the engine at full throttle on an engine dyno with the RPM varying from peak torque RPM to peak HP RPM in a 5 minute sawtooth pattern for 400 hours or 16 days and 16 hours. After the 400 hour run is finished, the engine is torn down to inspect for fatigue induced cracks or excessive wear. The criteria for passing is zero cracks and wear within allowable limits...one crack or one piece worn a little too much and it fails. The LT5 was the first engine to pass the 400 hour test...it use to be 200 hours.

As Paul said, the HOTB is a great read, I highly recommend it!