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89 ZZ4 Engine Project

8

89ZZ4

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I thought I would start another thread on my "just done" engine project on my 89 for those that have questions or want information. Last summer I finally got my first vette and I will tell you I'm over 50. Rational was I could buy a new one, but for a toy the depreciation thing didn't make good sence and I wanted something to modify to make it my own. So I tumbled on to my 89. Bright Red Coupe - 6 speed - Z51 suspension - 8,500 miles on the odometer! Not my color but equipped with the suspension and trans of choice with out all the potential problems of the adjustable shocks. I wanted an all around nice weather car I could cruise in, take a trip in, run at the drags, run a little autoX. Only major downfall is HORSEPOWER and a brick wall at 4800 rpms. Now understand my dailly work cars have included the 97 Taurus SHO, 90 Shelby IROC with the 224 hp twin cam turbo, Mitsubishi CV4 4WD and 5 speed and others including a 70-1/2 Z28 with close ratio 4 speed and 3.55 rear and a 69 Road Runner with Cold Air Hood, 4 speed, 3.91 rear and manual everything. I love cars, I love good handling, I love a engine that will at least do 6000 rpms and gets out of it's own way. Of course I would never put the "peddle to the metal" and break the speed limit, thus I have never driven a car faster than 145ish. Now to my build up. I don't mean to offend purists by pulling an engine with 10,214 miles on it but I scored a ZZ4 crate engine with only 500-700 miles on it that was partially disassembled for about $1,000. My son the GM tech told me about it after he had double checked everything and did the reassembly with new main bearings and bolts. I decided against pulling the heads again to have them pocket ported as I was trying to keep the project under 20K all said and done. Continue to next post.
 

-=Jeff=-

Well-known member
Joined
Feb 2, 2001
Messages
909
Location
Bartlett, IL. (Chicago Suburb)
Corvette
1990 ZR-1
IMHO you should pull the heads and get them CNC machined.. Here is why I say this

I built a motor for my 89 6spd. here is the list of specs:

10:1 compression
ZZ9 Cam
Miniram
1.6i/1.52e rockers
Long tube headers
52mm TB
Stock Pocket ported 89 L98 heads

Best 1/4 mile was 13.8 @102 (not sure on MPH)

Last year i swapped the heads for a set of 89 vette L98 CNC ported heads

Best 1/4 mile was 12.82 @ 110

Your stock heads (even though they are ZZ4 heads) are the same as the OEM 89 heads. they will be your restriction
 

69MyWay

Well-known member
Joined
Jul 3, 2001
Messages
4,364
Location
Auburndale, Florida
Corvette
1969 Killer Shark
Great stuff! Are you going to document the project on a homepage/website?

You will find a whole new world of C4 excitement beyond the 4,800 RPM barrier with those mods.

It just puts a big ole grin on my face to casually run through the gears and hold them until about 5,400 in 1st and 2nd getting on and off the highway and having the XL98 just beg for more.
 
8

89ZZ4

Guest
89 ZZ4 Engine Project - continued

So I now have a nice solid foundation that will take more buildup
and has a nicer valve train with the LT4 valves and a better valve seat grind than the stock engine. I was trying for a balanced approach for the car. From a cost stand point I had looked at a nice used TPI set up with the Big Mouth Manifold manifold, siamesed runners and ported plenum I could have gotten for about $650 (all polished) but after looking at it the model year difference in the runners and some other things that were done to it scared me off plus it still wouldn't handle 6000. If I bought new, sourcing from all over, the same type of set up would have been about $900 into the manifold/runner/plenum combo so I bought the TPIS Mini Ram II. TPIS was very helpful during this process including giving me thumbs up on some competitors products that were cheaper than theirs. For the extra $300-350 I got the best choice in manifold technology for what I wanted last fall (9/01). Stealth Ram was not out at that time. Full set up list: TPIS Mini Ram II for standard aluminum ZZ4 heads - 52MM BBK Throttle Body - Open Air Lid with TPIS Foam Filter - Fully Modified MAF - 180 thermostat - 1 3/4" TPIS coated headers (I'll tell my story later on the effort to get 1 5/8" LPE headers) - TPIS Cat Back Exhaust System - TPIS ZZ-409 Cam - TPIS Prom for the set up and I'm running the stock 3.33 rear. Injectors are stock. Am keeping the stock main Cat and expect to pass IL emmissions. The suspension is stock Z51 but I have new BFG Gforce KD's (Dry weather only) and will be installing the RD Engineering Camber Brace and more later on. I was going to do the change my self with my son but he was spending so much time getting his 94 Z28 (475-500 hp) sorted out he got a local shop where he had worked at to do the switch for a reasonable price as there's always shop floor engineering that has to happen. I wanted the car NOW! They also installed a B&M Short Throw shifter I bought. Original clutch/pressure plate/heavy flywheel were super clean so only needed new pilot bearing as insurance. Had to use ZZ4 valve covers as the Vette ones off old engine did not fit correctly. It was more than just cutting off some drip tabs. Picked car up Wednesday AM and drove it to work. Thursday son on took car in and changed oil and filter as we had new main bearings. No leaks but some minor header rub issues. This weekend I will post driving experiences - Try to post before and after pictures, etc.. SAVE THE WAVE! :w
 

-=Jeff=-

Well-known member
Joined
Feb 2, 2001
Messages
909
Location
Bartlett, IL. (Chicago Suburb)
Corvette
1990 ZR-1
Cool!!! Once I get my vette running I would like to meet up with you sometime.
 
8

89ZZ4

Guest
Jeff you are right about the heads as the bottle neck now but these were already newly put on so I decided to forgo the 25 - 35 hp the head work would net. Plus I forgot to add to the previous post I put on 1.5 ratio BowTie self aligning roller rockers. I'm going to sort this thing out over the summer and enjoy it once I get it properly dialed in but it looks like my cam choice dropped a bit of torque vs the ZZ9 cam but it's there in the higher rpm ranges PLUS. I made the mistake of giving it a bit of gas Wednesday and I couldn't shift fast enough in 1st or 2nd and was hitting 6300+. It's a bit slow out of the hole but by 3000 it's cooking. The 3.33 also contributes to this issue but right now it's running way too rich so I have my list of things to go over after a nice talk with Chris up at TPIS. Originally when I talked to them last year they were the ones that recommended the ZZ-409 over the ZZ9 even with the stock ZZ4 head which is the L98 head except for some minor changes and newer production techniques in the valve grind area and the lighther valve train. I did not push the gross spring limit with higher ratio rockers on the exhaust because the safe lift max on the LT4 springs is maybe? .550 and the 1.6 ratio on the exhaust pushes theoretical no deflection gross lift to .552. I want a warm street engine that I am not stressing. Spending money on the heads can be a future project if I use my old heads for it while I drive what I have or new heads like AFRs. Believe me I would have gone the fast burn route had I went with a new crate engine but mine is pure stock with just the edges of the in/out ports cleaned up. I don't have track numbers for the old stock setup but I will be disappointed if I can't do 13.0 or better in the quarter. I did ask TPIS today if my rich condition could be the longer duration + higher lift ZZ-409 intake profile vs the ZZ9 cam intake but both with the same exhaust profile as an issue. They felt NO. We'll see.
Chris (69MyWay) Hadn't planned on a web site - I will be challaged to get pics attached to this site over the next few days. I've taken some pics to document and will do more as time and my skill using this new digital camera I bought allow.
Everyone be good - but not too good! :beer
 

maxrevs85

Well-known member
Joined
Dec 17, 2001
Messages
709
Location
Eaton Rapids, Mich
Corvette
!985 ,blue coupe, 4+3 Z51
Great project you have going. I think it will be a nice combo. I do have to agree with the head thing though. But its somthing that can always be changed. I'm going with the AFR 190cc fully ported and 1.6 rockers. The cam hasnt been decided on. My engine builder works pretty close with compcams and is going to discuss this with them . After listening to everyone about the mini-ram , I believe it is the best choice. The other systems do still hit the inevitable 4800 wall. I will talk to tpis about the whole deal too. They are very helpfull. Sure would be fun to get all these engine projects (finished) together in one place. Man would we have a blast or arrested.:D ( Kens is the monster motor :eek )
 

-=Jeff=-

Well-known member
Joined
Feb 2, 2001
Messages
909
Location
Bartlett, IL. (Chicago Suburb)
Corvette
1990 ZR-1
89ZZ4,

I think the reason that Chris suggested the ZZ409 csm over the ZZ9 is to compensate for the smaller head. As I understand it if your heads are te bottle neck, the cam can be bigger to make up for it, in your case mainly the intake duration.

Sounds like a nice set-up. As i said before I would like to check it out some time

Jeff
 
8

89ZZ4@Home

Guest
Jeff - You are correct on the ZZ-409 cam suggestion by my way of thinking. With it's higher lift and longer duration on the intake I looked at it for the 12-15 hp gain on my set up and the TPIS answer to the Hot Cam using a 1.5 rocker ratio. They design their base lobe profiles for a 1.5 ratio vs a 1.6. Either way it looked like a great set up for me. Yesterday I resolved all the header rubbing issues I had and reset the fuel pressure to the 46-47 starting base. It was well over 50. Too cold today plus honey do's. I need to re-adjust the rockers before I do any more driving as they lightly clicking. After I get the over rich idle sorted out then new plugs, the camber brace and I found out I've got the "Frisbe" which I'll dump. Over the next few weeks I will get a full break in done right then I'll really know what I've got. :cool

Phil (aka 89ZZ4)
 
8

89ZZ4@Home

Guest
Hopefully this picture is small enough fit file size requirements.
 
R

REO1

Guest
ENG. CHANGE

I'VE ALREADY DONE THIS CHANGE WITH THE EXCEPTION OF THAT I USED A NEW ZZ3 CRATE ENG. AND THE HEAD WORK WAS DONE BY COMPETITION ENG. SERVICES AND I DID NOT USE THE INJECTION. WENT WITH A CARB. SET UP, HOOKER CERAMIC COATED HEADERS, T C I TH400 TRANS. AND 3.73 GEARS, IGN. MODS, MANUALLY CONTROLED COOLING FANS, THIS WAS ALL DONE ON MY 90 MODEL, MY 89 IS STILL STOCK. AND MY DAILEY DRIVER, IT HAS 58000 MILES ON IT AND THE 90 MODEL HAS 22000 MILES ON IT. THE 89 IS 1 OF 2200 BUILT WITH THE OPTIONS IT HAS AND I DECIDED TO LEAVE IT ALONE. THE 90 IS LIKE NEW AND I HAVE ALL THE STUFF TO PUT IT BACK STOCK, BUT I WANTED SOMETHING TO PLAY WITH. I DID PUT IT ON A NEW ZO6 THE OTHER NIGHT, FROM A RED LIGHT. HE JUMPED ON ME AND I PUT IT ON HIM REAL BAD. IN 1ST AND 2ND. I PULLED ABOUT 5 TO 6 CARS ON HIM AND HE QUIT. SORRY LOSER. TOOK IT OUT TO THE STRIP AND MADE A COUPLE OF PASSES AND IT RUNS CONSISTENT 11.90s-12.0s 116-118 MPH. NOT TO BAD FOR A STREET CAR.
I'M INTERESTED IN YOU PROJECT, KEEP THE INFO. COMING AND UP TO DATE, HAVE A GOOD TIME, AND TAKE CARE.
DUANE KIRCHNER
 
8

89ZZ4@Home

Guest
Another entry in my engine change saga. About a week ago I finally got to readjusting the rocker arms. Won't go into detail but wanting to do it myself I didn't do a very good job. Had several studs that have screwed up threads that make me use a wrench to turn the adjusting nuts. After I started it up I could tell it wasn't perfect but I wanted to test drive it around the block but ran out of time last Friday night. Saturday morning was fantastic in the Chicago area - Oh Boy! I get to drive the vette. NOT - Made it to the end of the driveway it dies. Well I had to jump the battery to get things going so maybe it's shot. Look things over - check connections and the post in the back of the alternator that handles the voltage regulator falls off in my hand. The engine change guys either over tightened it or it was already on it's way to vette heaven. Lucky for me the guys at Pep Boys had a new
one so I did the old change out routine in middle of the driveway. At least I waved at lots of neighbors. In the later afternoon I finally drive around the block but the rockers aren't right so back into the garage. NO CRUISING - Sunday was fantastic also but had to do the chores. With consultation from my live in mechanic who wasn't around to help me - told should
redo it right and maybe new studs would be a good idea - and told I better not give up my day job as I'll never make it as a mechanic. Takes me two days to find new studs - not a Pep Boys stock item. Wednesday night I redid drivers side and put in new studs (ARP) along the way. Idles better. Last night did the other side as I had a spare person to bump the engine. Much easier. Did find where I over tightened a couple of rockers and this time I went with 3/4 turn past zero lash and did everything warm vs 1 turn. The new studs made job easier with everything turning easily. Finally did it right and got a signoff by my live in Mechanic who's never around when I need him - only around for a check out drive at 10:00 PM on way to bed. Just a few times around the block. Rockers good but still running way rich although the plugs I puller looked ok. Just received my test harnesses from MAD so I get to check out the TPS and other goodies some over
next few days but I can drive it finally. Only observation so far is oil temp got higher than I'm used to 215-218 vs 195-200 and water ran 195 - 205 vs 190 - 200 but this is a warmer engine.
More later.
 

69MyWay

Well-known member
Joined
Jul 3, 2001
Messages
4,364
Location
Auburndale, Florida
Corvette
1969 Killer Shark
Roller rockers, or stamped steel?

I think I finally have the rocker science (get it!) figured out after many a screw up.

Stamped steel stockers are a piece of cake. I realize I may give up some hsp, but I always set mine cold and have been fortunate enough not to have to go back and re do them. Setting them running is messy, and going back in to the engine later is always a pain.

On stamped steel stockers. I follow the G.M. service manual and roll the engine to #1 tdc, then adjust in the suggested sequence, then #1 180 degrees out (#6 @ tdc), and finish the other 8. On stamped steel, I go 1 full turn after zero lash as G.M. recommends.

On roller rockers, I do the same sequence, then I turn the main nut 3/4 of a turn after zero lash. Then, I hand tighten the center poly lock into place. I then take the wrench on the large nut, and alan wrench on the poly lock and continue to turn both together clockwise. I usually can't get more than 1/8 turn on that last part. I have seen people do what I use to do, and that is try to hold the large nut in place, then tighten the poly lock against the stud. That will back off, I promise. By turning them both, you get the torque of the large nut threads bottoming the poly dead into the top of the stud.


Rockers too tight will make the engine hardly run as it holds the valves open, and too loose it makes terrible noise.


Keep us posted. Can't wait to hear your kill stories.


Did you hook the oil cooler back up or not? If it is hooked up, you should not see those kind of temps.
 

-=Jeff=-

Well-known member
Joined
Feb 2, 2001
Messages
909
Location
Bartlett, IL. (Chicago Suburb)
Corvette
1990 ZR-1
89ZZ4,

what brand PROM are you using? I have a feeling that is your problem for running rich.. what injectors do you have? what is your Fuel Pressure set to? Assuming you are using the stock ECM, I have a PROM you may want to try out. Also if you have Diacom or such it will help to find where and possibly why you are running rich.

I myself have EASE diagnostic software which works great for helping me tune my vette

Also as far as PROMs go.. I will not mention names but I have seem the code from some of the Tuners PROMs. I had one myself, in fact when I had it done I specifically stated 24# injectors.. when I looked at the code.. it was still set for 22#.. I was running rich as well. I think if you are willing to give the PROM I have a try you may be impressed.. It was running excellent in my car.
 

69MyWay

Well-known member
Joined
Jul 3, 2001
Messages
4,364
Location
Auburndale, Florida
Corvette
1969 Killer Shark
-=Jeff=- said:
89ZZ4,

what brand PROM are you using? I have a feeling that is your problem for running rich.. what injectors do you have? what is your Fuel Pressure set to? Assuming you are using the stock ECM, I have a PROM you may want to try out. Also if you have Diacom or such it will help to find where and possibly why you are running rich.

I myself have EASE diagnostic software which works great for helping me tune my vette

Also as far as PROMs go.. I will not mention names but I have seem the code from some of the Tuners PROMs. I had one myself, in fact when I had it done I specifically stated 24# injectors.. when I looked at the code.. it was still set for 22#.. I was running rich as well. I think if you are willing to give the PROM I have a try you may be impressed.. It was running excellent in my car.


Jeff, it is interesting you mention this. I have the stock 90 injectors and stock computer with the miniram, edelbrock heads, headers, and crane 2050 roller cam. My car is very rich at idle, enough to smell bad if you walk behind it (gets stuck in your clothes, and my wife hates it).

I can't remember the specific fuel pressure #, but I have basically backed the TPIs adjustable regulator all the way out, and still have the problem.

So, what do you thing about that?
 

-=Jeff=-

Well-known member
Joined
Feb 2, 2001
Messages
909
Location
Bartlett, IL. (Chicago Suburb)
Corvette
1990 ZR-1
69MyWay said:



Jeff, it is interesting you mention this. I have the stock 90 injectors and stock computer with the miniram, edelbrock heads, headers, and crane 2050 roller cam. My car is very rich at idle, enough to smell bad if you walk behind it (gets stuck in your clothes, and my wife hates it).

I can't remember the specific fuel pressure #, but I have basically backed the TPIs adjustable regulator all the way out, and still have the problem.

So, what do you thing about that?

Do you have a custom PROM? That maybe one of the reasons you could be running rich. Another could be that the Injectors are leaking causing the same problem.. One thing I do know is that when you buy a Prom from a tuner by just telling them your mods it is a hit or miss on the calibration.. EVERY car is different. 2 identical setups may have slight variations to get them running exactly perfect. Some PROM tuners will give you a PROM set for WOT and never touch the VE (Volumetric Efficiency) tables for idle and such.

I started my car up a couple weeks ago with stock VE Tables and it was WAY too rich. Since I have not programmed my CCM I cannot use EASE to communicate ( the CCM has the UART control) right now.. I got a friend to send me his BIN so I can get closer.. guess what.. I idle almost perfect now. It is not rich anymore. I think that is what you are having trouble with..

If you have Diacom or such record some logs at idle and cruising and send them to me in a Text or Excel format and I will look at them for you. I have decided that burning your own PROM, even if you take the Custom PROM and adjust it you will be much happier with your cars performance.

Jeff
 

69MyWay

Well-known member
Joined
Jul 3, 2001
Messages
4,364
Location
Auburndale, Florida
Corvette
1969 Killer Shark
Jeff, my PROM is stock. I did not feel like dropping $500 on that right now with TPiS.

That means the injectors could be leaking, but they did not leak/do this on the stock engine.

Tuning with the scanner installed watching the O2 at WOT in closed loop, it is all I can do to get it down to 900 mv. I guess ideal is about 860 mv. I can set the timing where I don't get any knock retard, and or about 1% or so under load and WOT. It seems to pull the best in these settings as the puter is not kicking the timing back.

I did the 52mm TB, miniram, cam, heads, and headers. Compression is a mild 9.6:1.

The readings you mention. Can I do those with my scanner. Are you talking about block learn, etc. etc. numbers?
 

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