I drove the car in the parking lot (its still not completely finished yet).

Things I noticed: It runs well on the stock chip, except it idles at 750 which is a little low for a stick. The Z06 clutch is pretty nice, nice and streetable, should hold the ZZ4 well if it holds an LS6. I ended up going with the stock plenum for now, SLP runners, Accell Base... like I said, I only drove it in the parking lot but I could tell it ran well, and the motor spooled up SO fast... way faster than the L98 ever did. I can't wait till it is completely finished.... still need to switch my mangled cats for a single 3'' catco into a Hooker catback.

My "tech" question: Is a 750rpm idle going to be a pain in the ***? Most stick cars idle closer to 1000rpm.... is the 750 going to annoying or at all a problem? I already know that lots of you are going to say get PROM burning equipment to fix that and make it run to it's full potential, bu what if I did leave it?

 

bro... it looks good... i gotta stop by and see it... let me know when u get into town... i wana see this beast!

 

Most excellent. Hey just a question, do you think the ZZ4 would work well with a stock TPI setup with automatic, lets just say you want to replace the L98 with a ZZ4 but use the stock stuff. Thanks

 

I did just that swapped out my l98 for a zz4 and just bolted all the stock stuff back up. Ran great 13.8 with 2.73 and auto but it did choke off big time around 4500. Then i put a stealth ram on it and watch out i dont have any hard numbers but i have no problems with any lt1's yet and beat most ls1's. But it really needs a chip now, i think its got alot of potential.

 

bigals87z28.... definetly. A combination of the fact that I am at Rutgers and the fact that my car has been sitting for the last 6 months equals the fact that I have not been around at all. Now that I've got it back I wanna meet up with you, and the other guy that is swapping a ZZ4 in his car from Jackson.

Benny, the ZZ4 will work fine with all the stock stuff hooked up. Aftermarket TPI parts will yield greater benefit, but the stock TPI will still produce a streetable beast. Especially with the steep 3.06:1 first gear in the 700R4 and all the torque of the ZZ4 TPI!

 

Ok fellas help me out here..zz4 in place of stock L98..emission problems at all? boy im salavating at the thought..woohoo...i know very vague question was just curious if anyone was running a zz4 setup with everything else being stock for the most part...thanks..

 

ZZ4 and emissions.... let me break it down for you.

Our F-Bodies came with iron L98 heads yielding a 9.3:1 compression and an emissions legal small block. The Corvette came with aluminum L98 heads which yielded a 10:1 compression and an emissions legal small block.

We all know the Corvette L98 is emissions legal... ZZ4 heads = L98 aluminum Corvette heads. So basically, swap a ZZ4 cam into a Corvette L98 and YOU HAVE A ZZ4!

So, the whole difference is in the cam. The ZZ4 cam is slightly hotter than a LT1 cam which is also emissions legal. Therefore, if you have a ZZ4 in good tune with working cats... you will pass emissions.

 

My car idles at 740. 750 sounds about right.

 

Man that ZZ4 would be nice but shipping it to Hawaii is $$$$

 

sounds good man... yo we are having a last get to gether at a bowling area in the central nj area...... its gunna be around teh 14th or the 21st... depends when kids get out of school for break... let me know.. im tryin to get it moved back... and good looks on the engine

 

Don't worry about shipping to Hawaii. Like he said,(since you have the L98) just change the cam and the heads. I know there's a little more to it than that, but It's a lot cheaper than shipping that crate. I don't think the stock manifold will match the holes in the heads, and there are no EGR provisions, but all in all, it's pretty straight forward. I'm planning on that swap myself.

I do have a question since were on the topic. What's the difference between the ZZ4 cam and the Lt4 Hotcam? Pretty close?

 

I don't know exact numbers or anything but the ZZ4 cam is somewhat similar to a TPI cam because it makes mid-range power, or maybe a tad higher.

The LT4 Hotcam moves the power band further up in the RPM range and makes more of it.

ZZ4 cam has a fairly smooth idle, whereas the LT4 Hotcams is rough and therefore doesn't stand much of a chance at passing emissions.

 

I beg to differ on that last sentence...mine passes NJ treadmill emissions easily at a nice, lumpy 750rpm idle. They don't evaluate idle smoothness, just pipe emissions.

 

You are correct. They do not evaluate idle smoothness. However, emissions legality and idle smoothness typically go hand in hand. Also take note, that I did not say the LT4 Hotcam can't pass emissions. It is just a fairly radical cam and pushing the limits of legal and can be very difficult to pass with.

So, you pass with the LT4 Hotcam in NJ? That's awesome... kinda makes me mad, because I wanted to do the ZZ4 with the Hotcam and 1.6RR. How close are you to failiing, on both the idle test and 2000rpm test? I am interested...

 

I live in NJ for 16 years, yeah, they are pretty strict. Down here in NC it's not so bad.

I imagine that the Hotcam would NOT be a good cam with long runner intake....is that correct. (not that it wouldn't work).

 

Its a tough cam to use because it puts the power band right where the TPI limits you. People do use it on here with great success... it would work extremely well with a Miniram.

 

How do you like that Acell/slp intake combo? I currently trying to figure out what intake to use. I like that complete Accel super ram with the medium length runners.......as well as just about everything else, but that long tube design is just SOOOOOOO sexy Seriously, I'm keeping it for the looks, but of course, I need it to perform as well. From the sound of it, it looks like you're doing OK with your set-up!

 

I put the ZZ4 in my car a little over 2 years ago with the LTR setup on it with the superram base. It definately ran better than the stock motor, but I still wasn't impressed with it. I worked with it a little trying to tweak it, but the best "recorded" time I ever got in it was a 13.7 @ 102 at a very crappy track(the only track that it has ever been run at). About 10 months ago I broke down and bought the Miniram...I have to say that this intake made all the difference in the world to that motor. I didn't loose any low end power, and the gains up top were great. On top of that I just finished installing a T56 six speed into the car yesterday, so it feels way better than it did with the auto. I would definately recommend a shorter runner intake to help in the upper rpm's...I have heard that the ZZ4 with the HSR runs great also.

 

I don't consider 218/228 @ 50 Very radical...

 

Bort... in the grand scheme of things its not. But for a street car that needs to pass NJ emissions, it is pushing the limits of legal and is therefore radical based on that logic. When you listen to that cam idle, you know its a muscle car!

I haven't driven driven the car yet.... just listened to it right and let the clutch out quickly in first gear in the parking lot. So all I can tell you right now is that it seemed to run really good with the Accel Base, SLP runners, stock plenum and 24lb injectors on the stock chip. We shall see when I actually get it out on the street and give it some R's. Trust me, that day can not come soon enough.

I am currently waiting on the rear end to be rebuilt with 3.73's, the brakes to be changed, the SFC's to be welded in and then for the single cat Y pipe, 3'' catco cat and 3'' hooker aerochamber to be put on.

I am having trouble finding a Y pipe.... Isn't there a Y pipe that is 3'' and will bolt up to the 3'' catco cat, or am I going to have to get a 2.25 y pipe and make it larger to bolt to the 3'' cat. I do not want bottlenecks, so a 3'' system the whole way would be nice. If anyone has suggestions or better yet, part numbers, that would be great. Thanks in advance.

 

Neither would I. The ZZ4 cam is small in a 350.
ZZ4 208/221 and .474/.510
LT4 .525/.525 (w/ the dur. above)


The stock TPI setup can't feed a stock 350 much less a ZZ4. I dyno'd 267hp and 356tq. That puts me close to 300fwhp. It took 50hp away just b/c it couldn't make power past 5000rpm.

The ZZ4 is nice, but if had to do it again, I'd build my own motor.

It is a little better than a L98 w/ a cam and corvette heads.
PM rods/ forged crank/ 4bolt main/ offset wrist pins/

 

l98iroc-Were you talking about me? I'm from jackson and I'm doing the zz4 cam in a l98 block.

 

nah bro.. Jakson NJ... hehehe not Mo... hehehe its a town close to him..... well... me too

 

go with my 3" system - very easy to install

i got my system hooked up for less than $500 for the headers, hi-flo cat, another test pipe, and cat-back.

if you want just the y-pipe, lemme know and i might be able to get it hooked up for you

 

I did the ZZ4 conversion with other mods over the last year. I live in California and had to pass emissions in August of this year.
My idle is set to 800RPM and it's pretty smooth with a slight stumble. I have the large runners and base, porting, 58 TB,etc., etc.. (see sig). Also in prep for nitrous installed the MSD digital 6.

Bottom line:

1. Car passes Ca. emissions easily.
2. Big improvement over the 305 TPI.
3. Wish I had a manual transmission (maybe next item).
4. Bottom end is real strong - car pulls hard to 5000 and to 5500
in 1st and 2nd.
5. As others have mentioned a better intake would make it rip.
Unfortunately, the mini-ram won't do the smog thing (I wish it would, but no EGR).
6. 3.73:1 is nice with the 700-R4 in the mountains - I think for the strip 3.40's would be better.
7. Thought about the Hot cam and 1.6RR but it's too much work on this car. Right now I want to drive it. Next car ??

The car is fun but definitely not the fastest thing around. My C5 vette friends love to drive it - from 0 - 75mph it's a blast. After 90 - well, that's where the C5 lives.

 

Isn't a 58mm TB too big for a ZZ4? Keep in mind a ZZ4 is a corvette L98 with a ZZ4 cam.

The stock 48mm TB leaves a little to be desired since the stock TPI is designed for a 305. Therefore, I could see stepping up to a 52mm TB. Wouldn't a 58 slow the car down?

I want to put SuperRam plenum and runners on my car, and I want the airflor coming into the engine close to stock so the SuperRam doesn't bog it down with air and slow it down.

 

L98iroc89, that 58. 52, 48mm stuff you just said is not correct IMO. If you want the airflow coming into the engine close to stock then leave it stock. dO A search!!!

 

How is it not correct... I don't need to do a search because I understand the underlying concept of the TB sizes. However, I thought that the 58mm flowed at near 1000cfm and would bog it down with air. Further, I thought the stock TB was good up to 400hp, which the zz4 falls short of by about 50hp.... by even more than 50hp with a TPI on top of it.

I'm not doubting your car... just thought that it was too much. Hell, if it runs well with it and gives nices gains I would get one too... I'm not just purley against it or anything like that. Maybe me data is incorrect and you can correct it.

 

Bog it down with air!! That is pretty funny. Hey, I am gonna try my 406 on the stock TB. I guess I'll see.

 

OK, the throttle body debate goes on. What the 58 did to my car was made it more difficult to take off from a stop and not break the tires loose (I think they call this driveability). In the overall scheme of things it's the conductance of air through the entire intake that makes a difference at WOT. The TB helps but has only a minor effect if the rest of the system (runners, MAF, air filters, etc., etc..) is restrictive. The net air flow will only be as good as the most restrictive element. Other effects of the 58mm:

1. It looks great (but only if you remove all the other stuff so you can see those beautiful big holes).
2. It wreaks havoc with the cruise control (yes, mine is still functional) - makes it a little jumpy.
3. Maybe it helps with an air-starved ZZ4 with TPI.

If you follow the folks in the know, I think a 52 would be fine. If you go to a 383 or 400 stroker, you want the 58. I like my 58 but make no claims as to the absolute benefit.

 

Hmmm.... yea I think a 52mm TB is in my future, but the SuperRam plenum/runners will definetly come first. 52mm TB would be the last straw on teh stock chip and therefore mandate some PROM burning equipment.

 

Yes its all true. The zz4 is a good starting point for making good power. This is for all you guys out there that want to install a zz4 in your car. The hp and tq numbers of the zz4 was based on a carb configuration w/longtube headers and 750dp carb. So of course the tpi numbers are going to be lower because of the intake design. Get a Mini Ram like I did. It's well worth the cash.

GM came out with two diff engines one for the f-body and one for the corvette. And of course both engines maintained the same compression ratio. The only difference in the two engines was the corvette had aluminumn heads w/58cc chambers and the f-body cars had cast iron heads w/62cc chambers.

I know it sounds strange, but true. Corvette's had thinker head gaskets creating 9.3 to 1 overall compression. While the f-body got thinner head gaskets to maintain that 9.3 to 1 ratio. So those of you think the corvette engine is alot diff from the ones in the f-body there you have it. It's just the heads

So you see just by adding the zz4 cam still does not give you the same numbers as the zz4 motor. It was said before the zz4 has alot of good performance parts on it that is why it cost so much. We all heard the saying " you get what you pay for".

Parts list- just naming the good stuff that support power!

- forged crank
-PM rods
-performance oil pump
-four bolt main

 

It has a forged crank?

 

Will the heads that the ZZ4 come with accept a stock TPI setup, do the bolt holes match up?

 

I believe they come with nodular iron cast cranks.

 

The earlier zz4 motors had nodular cranks. Gm just started putting forged crsnks back in the motors

 

My crank is forged.

The heads that come w/ the ZZ4 are NOT emissions legal. At least not for the price you see in the catalogs. There are NO EGR passages.

 

You raise a good point. The heads on the ZZ4 are not emissions legal as there are no EGR passages.

However, the ZZ4 heads ARE the L98 aluminum Corvette heads and they do not have EGR passages either. The Corvettes use an external EGR, which is what I had put on mine. Problem solved.

 

Any update on you ZZ4? I am thinking about the same swap. Curios if you got it out of the parking lot yet

 

No...

The SFC's and new exhaust has been put on. Now we are just waiting on the rear to be rebuilt with 3.73's, and for the Abbott Cable-X box to be installed so that my mechanical speedometer will work with the electronic output of the T56.

Trust me, when the car comes home with me, you all will be the first to know. I will drive it around and report back everything I notice. Also, I must add that it should be later this week that it is finished..... most likely Friday. I'll keep you posted.

 

sounds like you have one heck of a car L98IROCZ89!!

 

u guys out there wit the zz4's and the stealth ram's and mini ram's gotta get out there to the track and get some numbers asap cause thats a setup that i'm very very intrested in!!!!:hail:

 

Planning on going this weekend. The weather is going to be great, if I can just get away from work.

 

screw work i NEED to know what kind of numbers your goin to run!!!:hail: :hail: :hail:

 

The Formula has a ZZ4 with a TPI setup. It passes emmissions with 1 5/8 headers through a cat with the air system. From the top, the runners are made by SLP, its got a lingenfelter intake, zz4 heads, 1:6 roller rockers. I forgot what the specs were on the cam were. My dad bought the car with this setup. Since he bought it we've put on a B&M flexplate. The stock one got a big crack around the center. Its my moms daily driver year round.

 

So, are ya gettin it back today L98? I know its late but i just came across this thread! Well, good luck today if you do get it. Mine should be running soon too, i hope. Let us know-later

 

Ah... I just woke up. I'm about to go home and see if it's done. It should be, I certainly hope so! If so, I am just gonna randomly drive and waste large quantities of gas... and then I will let you all know how it turned out. Unfortunatly, here in NJ, it is all wet out. Oh well, I had a great night last night in WestChester, PA, so things must follow suit by having my car all finsihed for me right? I'll let you all know...

86... We should meet up over my thanksgiving break. Even if the car is not done today, it will most definetly be done by then. I go home for break next Wednesday until sunday so we should meet up at some point. Try and get your running so we can cruise.

 

Any luck? I just got my water pump and dist. cap in so all i am waiting on is the chip. It might be running soon but not next week, maybe! Later

 

OK, heres the low down.

First off, it's wet out here (11/22/02) in NJ.

Some things I noticed while carefully driving on the wet roads:

-Throttle is sticky... how do I fix that. What I mean by sticky is it "idles" at 2000 or 2500 rpm whenever you put the clutch in. However, if you pop the hood and press the throttle cable in all the way, it idles beautifully at 750rpm. Also, if I am in 6th gear, for example, at 60mph and I take my foot completely off the gas with it in gear, it will stay at 60mph because the sticky throttle will make it cruise there even without a foot on the gas.

-It seems to run fine on the stock chip with the TPI components I chose. After driving it around for nearly an hour I only got Code 12 by my scan tool (I believe code 12 is the code that every ECM throws everytime which tells you it is functioning properly?) I have a HyperCrap chip also... I wonder if I should even bother trying that out?

-It sounds great with the Hooker AeroChamber and single 3'' CatCo cat.

-The 3.73s whine just a little.... nothign bad at all, actually sounds pretty good.

-Tranny seems great, although sometimes a little clunky into second gear. It does seem as though it is only clunky when the throttle is stuck and it is revving high.... is this possible? And when I mean going into second gear, I mean simply placing the gear shifter into '2' and not even letting the clutch out.

-Z06 clutch is real nice. Nice and smooth, not jerky at all. If it holds a 400hp LS6, it should hold this just fine.

-60mph in 6th gear = 1400rpm or so

-Speedometer works with the CableX box from Abbot, although under 15mph it bounces wildy all over the place up to about 80mph. It also does this when you are slowing down and get below 20mph or so. This doesn't really bother me, becuase the speedometer works perfectly fine after 20mph.... just smoothes out all of the sudden, and after 20mph is where you need it.

-Car rides nice and tight, especially over bumps with the SFC's in. The car does not have that cheap, ice cube tray feel anymore. Couldn't judge handling by any means due to bad weather.

-Although it is wet out, I can tell that this car is fast as hell. The motor spools up ridiculously fast whether in gear or neutral. I am going to have to be especially carefull about the police now... I used to think it was easy to speed before? Now, everytime I look down at the speedometer, I'm going way to fast.

Only thing I really need to address ASAP (besides the fact that I need to register the car again ) is the sticky throttle. If anyone knows any tricks or any way to fix that please let me know. I do not want to "idle" at 2000rpm when a 750 idle is achievable. I would also rather not have to get out, pop the hood, and press on the throttle cable everytime to slow the engine down.

Can't wait till its (A)broken in and (B) not wet out!

 

F'IN SWEET! Makes me all excited to get mine done already. Sounds good man. Remeber, don't go crazy with it just yet. I believe the car should not go over 5000rpm or something while in break in period. I'll have to look it up again. Sounds good so far, good luck with it! Not too sure about the throtle though. Is it a stock bracket/throttle body? Later-Bryan