Hey everyone: i have done a lot of reading on these forums today and have got a lot of good info but i just need a little more help and advice, i happen to own a 87 gta vertable with a 305 tpi and 700r4 auto tranny, now im planning on within the next year doing an engine swap just to get a little more power and etc out of the car, and i am looking at gms zz4 crate motor, now i guess my question is that i want to keep it a tpi setup and was wondering if it is worth putting the stock tpi setup that i have now on the new motor when i decided to do the swap or go with an aftermarket tpi setup, if the after market is were its at then who makes a good set up? and being that the car has a digital dash is there extra sensors or anything that i need to worry about or will everything basically hook right up, will i need to get a new computer? if so which one is a decent one to get? also i know from reading some of these other posts the auto tranny should be able to handle the power but the car has been in storage for the last 4 years and has only been out a little here and there is there some things with the tranny i should do beside filter and fluid change to make sure i dont ruin it? and when the motor arrives i dont plan on altering it all that much i just basically want to throw on the tpi stuff drop in and go but being that its a convertable are there other things i should do to the frame other that sub frame connectors to stiffen things up a bit so i dont twist anything, hopefully this isnt to repetitive but im just trying to narrow it down to my application and what all i need to do to get this to work... thanks for the help guys and any other info that i should keep in mind just let me know

thanks


steve

 

Madison, WI?

Reason I ask is whether or not you have emissions inspection/testing will be a factor in this swap. Nothing insurmountable, but needs to be addressed if applicable.

The stock TPI will kill off about 50 or more HP on that motor. Getting it back up to 355 GFWHP will be expensive. What you have to answer is how much that all is worth to you.

The MAF system will probably be limited in HP capability. Most would tell you to convert to the SD system. That will give you more power tuning capability, but will absolutely necessitate PROM tuning. The MAF with a 350 chip will run it okay up to its limit.

No particular sensor issues. Get a 350 knock sensor & module.

The aluminum heads of the ZZ4 have a slightly different intake bolt pattern than your '87 base has. Your options are to modify your base to accomodate that, get an '85/'86 base, or get a Corvette TPI base. Since the heads are the same thing the Vette TPI engines used '86-1/2-up, and the factory base has its limits, an aftermarket base for a Vette makes a lot of sense. Along with aftermarket runners, and aftermarket 52mm TB. And 22 lb injectors. And adjustable fuel pressure regulator. I have a bud who went with the Big Mouth base, TPIS runners, ported plenum, and 58mm TB (didn't need that big of a TB) on a ZZ4 that he highly modified. Since we have emissions inspection and testing here, he hooked up the EGR like a Vette.

The other option is to go with another aftermarket TPI system such as the Super Ram, or in a real departure from TPI, Miniram. My vote would be for the Miniram, or a modified LT1 intake.

I would do the typical TH700 mods such as the Vette servo and relief valve. And, a higher stalling converter would allow the engine to get into its powerband a lot sooner.

Check on the Chassis forum about subframe connectors on a vert. I'm not sure what your options are there.

 

yeah madison, WI we have no emissions here so that part is cool, i guess i want to get around 300 hp that way i still have decent drivibility along with alittle umph if i need it :-), and i was thinking with the ZZ4 i could potentially get there with little addons i guess, what exactly is the mini ram and how does it differ from the stock tpi set up that i have now? and why would the one i have now lose that much HP, is it a flow issue?? just trying to get all the knowledge i can if i decide to do this so it wont be to painful

 

If you're wanting to keep the tpi. Scoggin Dickey makes a tpi crate engine

http://www.sdpc2000.com/catalog/1578...rip-Engine.htm

I'ts pretty impressive and makes about the same amount of power as the zz4 just at a lower rpm.

~Roger

 

TPI has two problems with regard to power: Flow, and tuning. You can increase the flow with porting & runners, and tune the runners so they will do better than the stock 4500-4800 RPMs, but you're still only going to get effective power to about 5500 RPMs.

The Miniram is an intake that looks a lot like the LT1, but is made for the standard Gen I SBC ignition and coolant flow direction. It makes power past 6000 RPMs, and flows a lot better than the standard TPI lay-out. The Super Ram and Stealth Ram (forgot to mention that one before) will do the same.

The SDPC Vortec TPI engine is decent as well. Just a 2-bolt main block, but that's not a problem. You'll still need to add the aftermarket runners and TB, but you'd have to do that with the ZZ4 as well. The heads aren't aluminum, so it will weigh a little more than the ZZ4. It's got upgraded heads for more lift, roller rockers, and the roller LT4 Hot Cam, all good stuff. If you want to stick with TPI, it's a pretty decent choice. Of course, that same engine with a carb and RPM manifold would make over 400 HP.

 

yeah i guess i just like the way the tpi is set up and want to keep the car somewhat to its roots, but i do like that other engine better than the zz4 actually now if i were to decide on that motor would i still need to get the vette tpi system and base plate to put on it, which company makes a decent set of runners now? or could i still use that mini ram system and is there a huge difference between the stealth ram or super ram, in this applicaition which would probably give me the best performance?

 

You mean the SDPC Vortec TPI crate? It comes with the base. They have the EGR kit available, if you want it. Edelbrock, TPIS are two I know make runners.

I forget now which one makes a Vortec base, Mini, or one or both of Super or Stealth Ram. But, if you're going with the crate, it comes with the base. I believe the Miniram makes the most high-RPM power. But, don't quote me on that.

 

that scoggins dickey motor is dynoed with tpi on it too and from what i have read the scoggins dickey motor is a bit cheaper also its got 357hp last time i checked w/ aftermarket runners and headers

 

SDPC Vortec TPI, will this engine with all emissions in place and functional pass the emissions testing, including the exhaust "sniffer"? Texas is getting as bad as California.

 

It should be able to pass sniffer. Visual is another matter - maybe yes, maybe no.

 

Big question is the LT4 hot cam, I have been looking at it to go with the trick flow heads with egr. Paperwork on the heads should satisfy initial question and maybe the induction made by first something that supports egr.

 

I got a question on heads without heat crossover and corvette style intake (TPIS,Accel, Vortec TPI, Edelbrock) how does the EGR work? My friend gave me a corvette intake, it has the heat crossover port on one side of the intake, the EGR in the middle, the exit on the other side of the maifold, where it goes thru the runners back into the plenum and the rear port that exits into the header/exhaust manifold. Where is the exhaust gases being sucked from, on non heat crossover heads (vortec,fast burn, ZZ4) all these heads have one front and one rear coolant passages and four intake ports Please explain how exhaust gases enter and exit the intake manifold?

 

From an external tube coming up from the exhaust manifold.

 

Sorry, did some research and the search button and found the answer.