I've tentively (sp?) decided to swap in a ZZ4 instead of rebuilding the L98 in the future. I have a problem tho - I want long tube runners! I know I sound crazy but don't bother telling me that... I love the look and powerband characteristics of stock-stlye TPI. I was going to rebuild the L98 and hook it up with a superior LTR setup like Edelbrocks or a TPIS bigmouth/AS&M Runner combo etc... The ZZ4 comes complete with a different manifold however, and I'm worried that I'll have to spend more money to slap on an induction system if I have to take off thier manifold and get TPI stuff... can anyone key me in to the powerband characteristics of the ZZ4? How much low end, how much high end etc. Also, exactly what type of manifold is included with the ZZ4 and what would one have to do to make the engine fully functional once it's installed?

Thanks guys.

 

The ZZ4 is a relatively mild, but potent, carb motor. Its cam isn't very well suited to TPI as it is set up for some degree of high-RPM flow, unlike TPI in general.

The intake manifold that comes on it costs about $180 new. If' you're worried about that, you're in for a real shock if you haven't priced all those $$$ parts you're going to need to get a LTR motor to actually produce a comparable amount of power to a carb.

Look at it this way: a L98 in a Corvette was rated at 240 HP. A ZZ4 is rated at 345 HP. The 2 motors are identical; same pistons, same heads, same everything; the only difference is the cam and intake and the TPI vs. carb. So, bottom line is: take a 345 HP motor, put TPI on it, and voilà, instant 240 HP.... 105 HP loss. Or, turn it around the other way: you want your TPI car to go fast, put a cam and intake and carb on it, and voilà, instant 105 HP.

It's your money.

Here's all it takes to add 105 HP to your L98. Just think what you could do with something really good istead.

 

Pretty much summed up there! I'll tell you this, if you want to still go with a zz4 and tpi, buy the shortblock. I bought the fastburn385 thinking i was going to switch to carb, but i changed my mind and went with a miniram. So i blew a decent amount of cash for parts that i did not use, like the zz4 intake, distributor, and i took off the water pump for a Stewart's. Wish i could have went back and bought the short block and built a nice motor that way. Oh well! Look up a member by the name of L98IROC89 i believe. He just did a zz4/tpi swap. Ask how he is doing with it. Its mated to a t56 and he says the bottom end is really powerful, the bottom of the powerband that is. good luck

 

I have a bud who took a ZZ3 crate (same heads/cam/intake/pistons as ZZ4) and went nuts with it. TPIS Bigmouth (Vette version) and runners, ported plenum, CNC porting, shaved, zero-decking, extrude-honed plenum/runners/base/heads as an assembly, ZZ9 cam, 1.5 roller rockers, etc. With 4.10 gears and 2000 RPM stall, it ran 14.0's here (that's low 13's at sea level). It got a little too tweaky to drive in the snow, but it certainly retained most of the typical TPI characteristics. Passed emissions testing with ease, for instance.

As long as you don't insist on retaining stock runners, a TPI ZZ4 will run just fine. Might not have the advertised 355 HP of carb'd version, but certainly more than the 245 of the L98 Vette.

Oh, I'm using the manifold (and distributor, and oil pan/pump/baffle) that came off his crate engine.

 

This is how you save even more money. First get the 91-93 B-Body motor. It has the same bottom end but it is a two bolt main. It is about $300.00 cheaper. You can sell the heads that come with it. They are stock cast iron L98 heads. Second put the cam of your choice in. The cam that is the 88 iroc cam. Bolt up a good set of heads and use the Accel Super Ram base( it is alot better than the TPIS one) use the runners you want and your good to go. Your not looking to turn the motor more than say 6000 rpm so you really don't need the four bolt mains. If you were planning to turn more rpm, then you should get a mini ram or stealth ram. Remember that LTR make big torque, and that is what moves our heavy cars

 

Yes. Also, I LOVE the look of LTR's. I don't mind not revving past 6,000 in fact I'd like to rev to about 5800 or 5900 ideally. I think I got caught up and didn't think some things out. Can anyone reccomend a good budget crate engine that I'll be able to throw hi-flo TPI parts onto once the L98 is thrashed?

I don't want to go through a rebuild. I don't have the experience to do anything myself, and rather than pay a shop to rebuild a tired engine, I'd like a nice brand new one for around the same price.

 

Do you know how to swap a set of heads and put a cam in?

 

I have never done so. But once I have the right tools and knowledge at hand (a book) I am capable of such a thing.
However, with 116,000 miles on the ticker I would rather not touch the heads or cam... My plan is to get the bolt ons, including my idea for a superior LTR setup, and then when I have the money to make the move, slap everything onto a new motor or a good deal on an L98 rebuild if I come across a shop.