8t2 z-chev

that rainwater flooding problem was just with the earliest '82s,by mid-'82
the air cleaner lid and some other parts were modified to prevent the
problem.

chazman

iTrader: (4)

The issue was identified by GM engineers when they drove one through a car wash. The jet water spray had enough pressure to lift the flaps and let the engine ingest water. In the rain? I don't know. You'd have to be on full throttle for some time to let that happen. And in the rain, even with an LU5, you are asking for loss of control doing that.

scottmoyer

The LU5 did have a lot of issues, but water wasn't the only one. If the flaps open due to heavy acceleration in a heavy rain, the rain has direct access into the system. Granted, you have air filters in place, but they are mostly made of paper in the 80s. The 4th gens "fixed" this issue with their hoods by having the air follow channels in the hood that had drain holes to allow water to drain out.






When I had my '82 CFI in 1986, the car was always in the shop because the engine wouldn't run right. I bought the car used and the previous owner used duct tape to cover the air cleaner opening. I removed it. BTW, Chevy knew there was a problem with my car and a couple months after I got rid of it, I was offered a TPI replacement. I already got rid of the car when that letter showed up!!!!

chazman

iTrader: (4)

That's interesting. I wonder how much power and driveability it would have had with TPI - considering it's L83 cam and LG4 exhaust. Probaly would have felt like a peanut cammed LB9.

Coyote850

iTrader: (1)

Anyone accelerating hard enough in the rain to have the flaps open up does not want to keep themselves or their car in good health.

chazman

iTrader: (4)

For sure.

scottmoyer

Ok, look at it this way. Your car is sitting in the driveway on a slight uphill incline. The sky opens up with torrential downpours and water sneaks past the seals and drips into the CFI assembly, puddling in the lids and in the lower tray. The sun comes out and you decide to go for a ride to get some milk and when you get on it, the water in the lid, bottom tray and wherever else gets sucked into the system. Not good.

And I don't want to hear anybody say that they've never got on it to get past a car driving really slow in the rain or to get past a truck throwing road spray. We've all done it!! My car's flaps didn't require the gas pedal be mashed to the floor to open. Mine opened when I aggressively accelerated.

Coyote850

iTrader: (1)

The car should be in the garage if there's a .000001 chance of torrential rain........

But seriously, you say the flaps on your car opened up when accelerating aggressively. Not so with mine, I have to tromp it to get the flaps to open up. And thats not something I'm gonna do in rain of any sorts.

yaj15

iTrader: (3)

This is all very interesting. I'm learning a lot about the Cross-Fire cars on this thread.

I know that the LU5 wasn't around long but it seems like it filled a gap left by the older late 1970's carbed 350's until the L69 showed up in mid 1983. The LB9's and L98's took the torch of factory flagship performance after that. I still wish the L69 engine would get more respect in some circles. The L69 is a factory hot-rodded LG4 and to us thirdgen folks will always be held in a special place. The L69 is what signaled the return of performance and served as part of the basis for the LB9 and L98 engines that followed in later years.

I don't think it would have been asking too much from GM to improve the performance of the LU5 in addition to fixing the water entering the inlet issue. Maybe it would have been more prudent to put the L69 dual snorkel air intake on the LU5.

At the time, however, with all the new emissions and fuel economy regulations hot rodding the LG4 in to the L69 was a stop gap until the LB9 and L98 with TPI became readily available and started mass production. The TPI based engines allowed significant increases in performance while still meeting the new fuel economy standards and the emissions requirements.

With respect to not opening the hood flaps, keep in mind that these Gen 1 small blocks of the late 1970’s-early 1990’s generally had operating ranges from off idle to 5000rpm-5500rpm. These engines were tuned for torque; this is especially true with the TPI based engines. Consequently the power comes on strong and early in the operational rpm range and you don’t necessarily have to be accelerating all that hard to induce wheel spin or put enough load to increase the engine vacuum enough and have a low speed high engine load situation – which would probably make the flaps open to.

Try accelerating moderately or hard in an L69 5-speed car with 3.73 gears and you will find out quickly that not much throttle or a less than ideal traction situation is all that is required to induce wheel spin.

I know with my L98 when I first got it 11 years ago, I had been used to driving Toyota 4-cylinder cars. Toyotas are good cars but the power band didn’t really start until you got a little past 4,000rpm and there was not anywhere near the torque of the L98 available.

When I first got my car I lit the tires up coming out of Taco Bell. The sprinklers had run and just made the road slick. I hit the throttle to get out of the parking lot fast (in the same way that I was used to mashing the throttle in the 4-cylinder Toyota to get it to go) and the L98 hooked up with that low first gear in the 700r4 and that sucker spun tires for days. Ha ha scared me that first time because I wasn’t expecting it. After that I learned to have a healthy respect for GM V8 small block torque.

1MeanZ

iTrader: (9)

I think he meant that GM would have replaced the car with a later model TPI car, but I could be wrong. If GM would have retrofitted TPI to the older cars, I'd think we would see more of them around. I've NEVER seen an early thirdgen with TPI that anyone claimed was dealer installed. Considering the epidimec that was CFI, I would have thought we would have retrofitted cars floating around.

yaj15

iTrader: (3)

I agree. I really thought about getting an early '82-'84 Z28 when I was looking at getting in to my own thirdgen. Now that time has passed I find that those early thirdgens are either really nice or really horrible.

Every time I go on ebay or craigslist I am amazed at all the poor quality work that gets done to these early thirdgens. Most of them are cheaper than the '85-'92 cars. Most of them had the LG4 or L69 carbed engine so its easier to swap that out for a 350 or larger carbed engine. But still its just sad to see so many of these early cars in such bad shape.

GM made over 100,000 Z28's in 1984 and its very hard to find one thats in very good shape now.

I almost bought a 1984 Z28 L69/5-speed/3.73/T-Top car when I was looking at getting in to thirdgens. The car would have needed a lot of work though.

One of the previous owners got a cheap $300 Macco paint job and painted over the entire car in a color that was close to GM bright red. It would have needed new black hood stripes, body stripes, head light black outs, and blackouts for the holes in the bottom of the nose ground effects in addition to a new (properly done) paint job. My favorite color combination for the early Z28's is bright red with silver trim so that was a let down.

That car also still had the stock 15''x7'' Z28 wheels but they had been dipped in chrome and that was starting to come off. The inside was mostly stock and was all black and needed to be restored as well. That car sold soon after I decided not to go after it. The owner was asking $4,000 for it and I thought that was too much for what needed to be done to the car so I moved on. I sure hope that car is still around now.

chazman

iTrader: (4)

My flaps don't require full throttle to open, but certainly an agressive throttle application. Let's call it 3/4 or greater. Even with only 165 horsepower and 240 ft lbs of torque and a 2.93 gear, I really need to feather the throttle in the rain to restrain wheel spin and keep the rear end from breaking loose. It could very easily swap ends in the rain. I simply can't imagine myself driving that agressively in a heavy rain.

KITT1983

iTrader: (3)

i have a slight rough idle at stop lights @600-800 rpms

i have a 180 thermostat in my car will i have drivabilty problems?

no egr

chazman

iTrader: (4)

Remove and clean your IACs. Don't lose the springs.

IROCZTWENTYGR8

iTrader: (1)

There's a serious lack of pictures of said CFI commuter car here. Just sayin.

KITT1983

iTrader: (3)

I drove it yesturday when it was 10 degrees it ran like a tiger


My vaccum booster was leaking i believe caused it.

chazman

iTrader: (4)

Yes! Actually, I haven't driven it in a few months. I need to take some new pics. My old computer went ***** up and I haven't recovered the pics off it's hard drive.

82tarecaro

iTrader: (4)

Are you still doing the t5 conversion?
When you did your exhaust did you put larger manifolds on it?
I have my fuel system apart and I have to drop the tank for a fuel pump. I am contemplating putting a better exhaust on her with L69 manifolds but wonder if it is worth the hassle.

chazman

iTrader: (4)

Still doing the T5 swap - as soon as I can get all the parts together and get it to 1MeanZ.

As far as the exhaust, what a saga. What I REALLY wanted was to find a complete N10 exhaust and put it on. After some searching without success, I had a shop bend me up a 3" exhaust and 2.25" Y-pipe and retained the LU5, 2" exhaust manifolds. Within the next month, I found 2 N10s for sale. F^^%%$%$K!!!!

Shortly thereafter I ran across a pair of L69 manifolds, which required the custom made Y-pipe to be modified to fit.

Anyway, the exhausts are very restrictive on these cars. If you can change it to an L69/TPI/N10 it really wakes these Crossfires up.

82tarecaro

iTrader: (4)

Yes I am hoping to find a set of manifolds. I think Walker sells the Y pipe. N10 might be tough to find. I may have to settle for a high flow aftermarket cat. I have the dual resonator set up, which looks cool, but is extremely restrictive. I want to put something on that looks relatively stock.
What type of muffler did you use?

chazman

iTrader: (4)

I used a Catco 3" high flow cat. That's plenty of flow actually, I just wanted an N10 for the sound and I guess in my own mind, the "cool factor".

I originally had a Flowmaster muffler on it. I hate those things, but the exhaust shop really talked me into it. Could NOT stand it, I knew I wouldn't. It sounded cool on the outside, but from the inside, it felt like I was inside a 55 gallon drum with some one banging on it. The drone was just intolerable. I sold it a a few weeks later to someone on TGO for half price. I was in a hurry to get it buttoned up for the 2008 Indy Camaro Gathering so I had a generic factory replacement 3" in, 2.5" out, crossflow put on temporarily. It's still on there! Maybe I'll run across an SLP 2OTL for it one day.

82tarecaro

iTrader: (4)

Yes - Flowmaster is definitely not for everyone. I have one on my DD 5.0 HO. I kind of like it though. But I never liked the sound they made on a Thirdgen. I was thinking a Walker replacement or Dynomax. I still have time to do some homework. BTW - you can get the aftermarket N10 from Rock Auto. It sells for about 300 bucks. I am not sure how close it is to the originals though.
Thanks for the advice.

chazman

iTrader: (4)

Yeah, I'd go with either the Walker or Dynomax too.

I've seen a few N10 replacements. The one for $300 is the cheapest one I've seen. Walker has one for about $375. If I were doing it again, that's probably the route I'd take. In the end, it wouldn't have cost more than the fabricated one I have.

KITT1983

iTrader: (3)

What is the best for a performance exhaust? Sound and flow?

chazman

iTrader: (4)

So, I have a little dilemma. I've been offered a more than fair price for this car. In fact it more than covers what I have into it. I always figured I'd grab an offer anywhere near this if it ever came along. But......I don't know, maybe I'm attached to this POS. And just as I've collected all the parts needed for my T5 swap too.

One more thing. This car has never seen salt. Even in it's early life in rural Wisconsin, they use sand up there in the winter, not salt. Why is that of significance here? Because if sold, it would be used as a daily driver. Now that's fine in California or Arizona. But here in Chitown, that means this completely rust free car will see salt for several months out of the year.

I've got some thinking to do. What do you guys say?

yaj15

iTrader: (3)

I would keep it if I were you. You're lucky enough to have 3 nice thirdgens. You also hardly ever see a 1982-1984 Z28 that is in good shape anymore. They are either really in the toilet or in really good shape - there's not a lot of room in between anymore. Many of the 1985-1992 thirdgens are also falling in to that category now as well. That's part of why a close to stock early thirdgen Z28 gets a lot of attention.

It's your car and you have the freedom to do with it what you want. On one hand if you did let it go you could find another 1989 IROC with the LB9 / T-5 / G92 drive train combination that you like, that had more miles on it so you could use that car as a driver.

On the other hand you would always be wondering what happened to your 1983 Z28 as the one that got away. Your '83 also has the Cross-fire motor which was only around for 1982-1983 so that is rare. Ha ha and your LU5 works most of the time and you have gone through and taken care of most of the mechanical components so that you can drive it and have it be reliable. The LU5 also helped open up the door so that the L69 could come back and really give some performance back to these cars before the TPI motors were available.

Ha ha trust me if I was looking in to getting another thirdgen - I've learned a lot of lessons over the last decade since I've had my car - a car that works and is reliable (modified or stock) is worth a lot more than one that has problems. I love my car and I wouldn't want to get rid of it. That being said, however, if I knew now what I knew back then, I may have considered getting a car that needed less work to start with. Then again that also depends on what your goals are for the car that you purchase.

Out of the fleet of thirdgens that you have the 1983 is the one that you're able to have the most fun with. It's got enough miles on it to where it's doesn't matter that the car isn't going to be a mint 100% factory fresh original car where you would pull your hair out of if you had to drive it in the rain or it got a scratch here or there from being driven.

I would rarely drive your 1989 IROC, if I had it, for many of the same reasons that you've said before. That car is rare especially in the condition that you have it and you are the original owner! I wish my car had an original owner like you ha ha.

Your 1985 IROC has low miles, it's the first year for the LB9 TPI motor and, the first year for the IROC model. Even though you don't have posi on that car yet, you have the LB9 / 700r4 / 3.42 gearset drive train combination which was the hot ticket in the 1985 IROC's. While it's not as rare as your 1989, how many yellow IROC's in good condition do you see going around? Not too many at this point either. That's a car that's more of a driver than your 1989 IROC though.

chazman

iTrader: (4)

Yeah, I'm going to mull it over a bit. It would give me the flex and room for a T5 convertible. But I wouldn't want to see it used up as someone's year round daily driver, however.

82tarecaro

iTrader: (4)

I may have a somewhat biased opinion, but I think you should keep it. The Crossfires are rare and different, and the T5 swap would make it even more unique.
I have been tempted to sell mine over the years, or rip out the Crossfire system, but looking back, I would have regretted it, and wondered what became of the old girl.

1MeanZ

iTrader: (9)

If someone is going to buy the car and turn around and drive it in the winter, you aren't charging nearly enough for the car. If you're selling it that cheap I'm sure someone around here that appreciates it will buy it. Should have my bonus from work coming soon, maybe I'll make a bad choice and buy it!

chazman

iTrader: (4)

Don't worry Jeremy, I don't even have it for sale.

eseibel67

Are you blessed with unlimited storage space? Keep it because the Crossfire absolutely has a cool factor. If no, I would look at upgrading the collection by subsituting the Crossfire for a factory stock T5 convertible. T5 convertibles are hard to find, yet are still very affordable when they do come up for sale. If you're in this for the long haul, history has proven that the manual convertible is always the most highly desired hobby car in any series. The reasons are obvious.

If I remember, your 85 IROC is an automatic and the condition of the car is excellent, but a little short of immaculate. There's where the T5 conversion should be applied, because it would make a nice driver.

chazman

iTrader: (4)

Nobody has "unlimited" space.
Yup, a T5 convertible would be sweet. No way would I put a T5 in the '85. First, because it's a relatively low miles original, second because I just had it's 700R4 rebuilt.

BTW, this was an unsolicited offer. For $7500. That's what took me aback initially.

82tarecaro

iTrader: (4)

That's a tempting offer...

chazman

iTrader: (4)

That's what I'm saying, bro. Anyways, I don't think I'm going to sell it. The T5 conversion moves forward!

92RS(real slow)

When you bringing it down here for the swap?

chazman

iTrader: (4)

As soon as there is no salt on the ground or if I find someone with a trailer.

1MeanZ

iTrader: (9)

an enclosed trailer that is. Otherwise I'd go get it with mine and bring it over here. I'm scheduled to put a Quadralink in a '69 Camaro, but I talked to the guy yesterday and he's not planning to get it over to me until May or later, so as soon as the salt is off, we can start the T5 swap.

FormerL69

iTrader: (2)

Gotta agree and say keep it. I think I'd cringe knowing a decent car like that was a DD in Chicago. The thing would be a pile of rust in a matter of years.

KITT1983

iTrader: (3)

my 83 d500 is a daily driver in Boston and it is sill rust free and mint after 5 years

i would not want to see your car gutted and turned into someones race car or parts car

FormerL69

iTrader: (2)

I bought my 84 Z28 in 89 from the original owner. The car was only 5 years old at the time and had lived it's whole life in the Chicago area (where I lived as well). When I got it, my dad and I painted it because the car already had a ton of lower body rust. The metal behind the rocker extensions and the t-top bar had rust all over the place. It's unbelievable to look back on the metal repairs we did and to think that the car was already starting to disintegrate after 5 short years.

I agree with you that I would hate to see the CFI car gutted or turned into a race car. It feels like the first thing most people do with a CFI is remove it.

KITT1983

iTrader: (3)

i live near the beach and a salt water marsh (think California dry rot ) i wash the entire car including the underbody at least twice a week. i have a car cover for it when it snows.

my headliner and trunk carpeting is disintegrating due to old age and the New England climate.

every cfi car i have seen locally and and online have been gutted or resold with a high performance motor and then gutted for the motor and then scraped for parts (that was a 83 d500 pace car such a disgrace )

InfernalVortex

iTrader: (4)

Sell it. He made you a more than fair offer, go do something with it.

Who cares if he drives it in salt? If it manages to ruin another nice thirdgen then so be it, this is the process that is required to make original cars valuable, but chances are it's not gonna rot into nothing in a matter of 6 months. Hopefully he will sell it to another collector or figure out how unique it is and use it as a summer car before the rust gets bad. Either way, it's a fair offer, and its just a car. There are millions of these things out there even now, and you can get a VERY nice one for $7500 if you're that heartbroken over it.

And the main reason is that this car is unique because it's in good shape and it's original. Putting some iron duke T5 in it takes that away. Even if you get it working completely like stock, it's still not stock. So I'd argue you're cobbling up the car worse than this guy who might drive it in salt winter weather.

I know my opinion isnt popular, and I've got a T56 cobbled into my POS, but it's just an RS, not a stock 84 Z.

chazman

iTrader: (4)

No denying that the swap will entail some non stock hackery.

eseibel67

Oh no, driving in salt spray is the worst thing you can do to a car. The only thing worse is drving it over a cliff.

chazman

iTrader: (4)

Oh, for sure. My neighbor bought a mint, California, '67 Chevelle off of ebay. The shipper dropped it off at a depot about an hour away. Now, this was in the middle of a Chicago winter. It had just snowed and the streets were coated in that wet, slushy, salt slurry. Instead of flatbedding this rust free car, my neighbor went down to the depot to drive it back. When he pulled into the driveway, the car was covered in salt. You'd think job number one would be to at least try to hose it off. He didn't and just parked in the garage. A couple days later he hosed off the salt. I could see rust streaks had already started forming.

Jason E

My wife laughs at me because I won't even drive my WRANGLER when the roads are wet and salty

I am blessed to have a company car, so none of my own stuff is forced to see salt very often. For this stupid snowstorm we just had, I drove my 07 Duramax to work to help with plowing the lot. I felt guilty about driving it on wet, salty roads. I have seen sooo many cars succumb to rust over the years...its a shame what MA does to its roads in the winter.

Needless to say, the IROC, SS and Z28 do not see the light of day from first salt until we've had enough rain to wash the salt off the roads in Mar/Apr timeframe. My Z28 may have seen salt before I bought it in 2001, but since then? Never...and as long as I own it, it never will.

yaj15

iTrader: (3)

What computer and chip could you use to tune your LU5 with the 5-speed trans?

What manual transmissions came stock in the C3 & C4 corvettes with cross-fire 350 engines?

Could you use the computer and chip from those cars for your LU5/T-5 drivetrain combination?

chazman

iTrader: (4)

I'm thinking that the '83 ECM isn't smart enough to know the difference.

eseibel67

I think you may be right. Those early automatics are not electronically controlled. The only thing the computer would do it try to lock the TCC, which it won't be able to do since the converter will be under your workbench.

yaj15

iTrader: (3)

Hmm yeah thats what I thought. The best bet may be to try and find a 1984 Corvette ECM. Thats the last year the cross-fire L83 motor was available in the C4 so maybe that could work.

I'm guessing they came with the 4+3 manual transmission but, I'm not sure what differences there would be with respect to the computer.