BadIroc

My Iroc still has the very tired original 305 w/ 130k on the clock and I've been looking to do a 350 swap for quite sometime now. Now that I have money to spend on a decent crate I found an engine performance shop around my area who builds everything from short blocks all the way to turn key motors. They make a crate similar to one GM makes the 350/350 hp, unfortuantly the one GM makes is ony for pre emission vehicles. Well I called them up for some info on it the guy said it would be pretty compadable with my TPI, because i plan on keeping my TPI, but the guy said that they would have to put in a diffrent cam in for the TPI. The motor is a long block not including intake manifold 2500 bucks with the cam swap around 2650. They claim its a 350 horse motor. Here are most of the specs of the motor...
Cam is a Comp Cam with a .480 Lift and duration is 230 deg.@.050" and 110deg. Lobe Seperation
The heads are GM type Iron with 70cc combustion 150cc intake runner intake valves SBI Steel 1.94" Exhaust Valves SBI steel 1.50"
Compression Ratio is running around 9.5:1
Crankshaft inspected, remanufactured and balanced stock crank along with the same for the connecting rods
Speed Pro HyperEutectic Pistons w/ speed pro plama-moly rings
Block is thermally cleaned and stainless steel shot, inspected by MPI process. Bored, honed and pressure washed. With cam berings and freeze plugs installed.
Rocker Arms are factory stamped steel and comp cam pushrods.

I know this seems kind of long but i just want to get some opinions before i end up deciding if I want to buy this motor or not and if it sounds like its 350 hp like they claim it is. Again I plan on keeping it TPI...upgrading the throttle body to a 52mm, 24lb injectors, and a fuel pressure reg..And I either plan on porting the current runners or purchusing the edelbrock high flow runners and a Edelbrock Performer RPM intake. Iam also plan on throwing on a pair of edelbrock TES Headers. B&M 2400 stall for the tranny and B&M shift kit. gears as well sometime..probably go 3:73's. Its gonna be coslty but Ive saving for awhile and i dont want the car to rip 11's but mid to low 13's ill be happy and keep it a nice streetable daily driver.

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1988 Camaro IROCZ "MIDNIGHT CRUIZERS"
305 ci Tuned Port 700R4
3"Exhaust/Flowmaster 80 series muffler/Dynomax high flow cat/CutOut
hypertech chip/k&n filers, cut MAF screen gutted air box
"Theres no replacement for displacement"
My Iroc web page....
www.geocities.com/bobfitz82/index.html

86 IROC

The cylinder heads sound kind of weak to me, and the cam you listed sounds like it would give your ECM fits, it would be a PITA to tune w/ 110 LC - not to mention it would produce lower vaccum signals at idle; meaning some of your vaccum assited accessories might not work as well. I know I might get bitched at for this, but a ZZ4 is only $1,000 more - it has better camshaft and cylinder heads. It just depends on if you can afford to spend the extra $1,000 or not.

That engine shop's claim of 350 HP seems overzealous to me. It sounds like it had open headers, electric water pump, no air cleaner, etc. It honestly sounds like a 300 HP motor that would lope around at idle.

Oh well, just adding my .02 - good luck with your project.

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1986 IROC-Z, 8pt. cage, 383, Mini Ram, DFI, Art Carr 700R4, 12 bolt.....

RedIrocZ-28

That motor with YOUR TPI system is not gonna be anywhere near 350 hp I guarantee that. You could expect to see somthing around 280. Thats roughly my motor but with crappier heads. The cast iron heads that came on my TPI motor are part number 14101083. They had 163cc intake runners, flow 195 cfm intake side, and have 1.94/1.50 valves. My cam is bigger than that. Look in the sig. This is just a bad idea all around. Thats my opinion, don't buy that motor. Big waste of your $$$.

BadIroc

Wow, I apreciate all of the responses. Now Iam gonna think twice about it. I origionally was going for the zz4 crate but people were telling me i can't run my TPI on it or anyother type of fuel injection? is this true? i hope not cause thats a sweet motor. Cause I can get it through one of my relatives who works at a GM dealer and he can get a 10-15% discount off parts and thats including crate motors too and I was going to get that until I heard that I couldnt run the fuel injection with it..but if I can please tell me cause thats the onle I will probably go for. I was also looking at also the engines they had in summit the 350/330hp HO motor and the 350/350 hp recon motor...thanks more help would be appreciated!

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1988 Camaro IROCZ "MIDNIGHT CRUIZERS"
305 ci Tuned Port 700R4
3"Exhaust/Flowmaster 80 series muffler/Dynomax high flow cat/CutOut
hypertech chip/k&n filers, cut MAF screen gutted air box
"Theres no replacement for displacement"
My Iroc web page....
www.geocities.com/bobfitz82/index.html

86 IROC

Who told you the ZZ4 wouldn't work? The cylinder heads are basically what came on 88'-91' TPI Corvettes, and the cam isn't that big. I know of a few people running that cam in a TPI motor with success. At worst, you might need some PROM tuning & and adj. FPR. I'd be willing to say that a ZZ4 with good exhaust, proper tuning, and traction would get you mid 13's right off the bat - with more potential in the combination.

GMTech

I am basiclly running a "home brew" ZZ4, but instead of Aluminum L98 heads, I have Trick Flows, and instead of 4.00" bore, I have a 4.040" bore (357ci). I ran w/ an almost stock chip for while. I don't think the cam is the greatest for the characteristics of TPI, but it certainly is not a bad cam. Its actually kinda small, IMHO. ZZ4 is a GREAT starting point, especially if you don't want to build your own, and want proven HP. GM ran a 13.8 in there 3rd gen conversion, and thats in full emissions trim.

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Webmaster:SETHIRDGEN
GM Tech
ASE Master Auto Technician + L1
1987 Trans Am: 357ci
Ported TFS heads, ZZ4 cam, headers & exhuast and other go fast goodies
13.53 @ 103.77

BadIroc

Thanks! I think I'am going to go with the zz4! Is there any type of intake manifold that would work nice with that motor?

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1988 Camaro IROCZ "MIDNIGHT CRUIZERS"
305 ci Tuned Port 700R4
3"Exhaust/Flowmaster 80 series muffler/Dynomax high flow cat/CutOut
hypertech chip/k&n filers, cut MAF screen gutted air box
"Theres no replacement for displacement"
My Iroc web page....
www.geocities.com/bobfitz82/index.html

RedIrocZ-28

Just so you know, you aren't gonna make 350 hp when you bolt the TPI on. I am not sure if I made it clear enough before that the advertised numbers you see are not gonna be what you get. The TPI intake is restrictive. They probably used a perfectly tuned Carb with Open headers and no accessories to get those numbers.

GMTech

Make 350HP? Probably not, but the ZZ4 is still a great foundation to start with. With my motor, I ran 13.5 @ 103.77 w/ a ported Stock base and stock runners and stock throttle body.

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Webmaster:SETHIRDGEN
GM Tech
ASE Master Auto Technician + L1
1987 Trans Am: 357ci
Ported TFS heads, ZZ4 cam, headers & exhuast and other go fast goodies
13.53 @ 103.77

[This message has been edited by GMTech (edited July 14, 2002).]

86 IROC

My personal experience w/ a ZZ4 in a TPI car was a 1991 Z28 5.7L car. It had: ZZ4 crate motor, gutted cats, flowmaster muffler, edelbrock headers, SLP 2400 stall, and BFG DR's. Car ran 13.40's @ 100 MPH, hooked well. Had a stock chip and TPI unit.

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1986 IROC-Z, 8pt. cage, 383, Mini Ram, DFI, Art Carr 700R4, 12 bolt.....

Kevin91Z

I had a "homebrew" ZZ4 as well, with mild ported ZZ4 heads, a ZZ4 cam, SLP 1 5/8" headers, and a ported stock TPI intake. First the ZZ4 heads have a few problems, like the intake bolt pattern will require either an aftermarket manifold (preferred method) or an 85-86 F-body or 88-91 Corvette stock TPI manifold. Also there is an accessory hole missing on the passenger side that will need to be drilled and tapped. Lastly those heads dont have EGR so if you have emissions tests you will need to rig up a Corvette style EGR like I did.
That engine in my car made 282 RWHP and 380 RWTQ, and ran a best of 13.23 @ 107.18 MPH on drag radials. It idled smoothly on the stock chip, as well.
And, I very highly suggest you DO NOT use Edelcrock headers. They suck! Save your money and get some SLP's or Hookers instead. The ZZ4 heads have a raised exhaust port that just barely clears with 1 5/8" headers, and works great with 1 3/4". The Edelcrock headers have a lot of weld inside in the port that makes them more like 1 3/8" headers.

Do a search on this forum for more info about the ZZ4 engine and header choices. I'll also answer any more questions you have.

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1991 Camaro Z28
350 L98 w/ T56 (originally 305 LB9 w/ T5)
318 RWHP, 419 RWTQ
12.803 @ 108.50 MPH (1.932 60')
Member: SoCal F-Bodies
ThirdGen 4-Life!

BadIroc

Cool! Thanks for all the info. Yea I think that I'll go with the hooker headers insted, plus thier a little bit more in my price range then the SLP's. I dont mind spending an extra 30 bucks or so for the hookers. So is it hard to rig up the EGR on the zz4 heads?? Yeah I do have to go through the whole emmisions crap and where I live thier pretty strict thats why I can't go to nuts on a motor because this is my daily driver except for the winters. Will I also get away with running my stock intake manifold for awhile?? Cause ill probably be modifying my TPI either getting the Accel super ram or just sticking with the plenum I have and putting some edelbrock high flow runners and manifold base a little while after I get the motor in..probably this fall or somthing...thanks for all the help kevin91Z.

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1988 Camaro IROCZ "MIDNIGHT CRUIZERS"
305 ci Tuned Port 700R4
3"Exhaust/Flowmaster 80 series muffler/Dynomax high flow cat/CutOut
hypertech chip/k&n filers, cut MAF screen gutted air box
"Theres no replacement for displacement"
My Iroc web page....
www.geocities.com/bobfitz82/index.html

[This message has been edited by BadIroc (edited July 16, 2002).]

Kevin91Z

If you need an EGR then you really should get an aftermarket intake manifold. It will have the Corvette EGR holes already in it, while your stock f-body one does not. Then you'll need to modify your headers to add the exhaust gas tube on the #8 cylinder. Here's the pics of how I did it:
http://para.noid.org/~thresher/image...1&dispsize=800