I havent posted on this site in a long *** time so Hi. Im looking to get rid of my 305 tpi motor in my formula. I ran across a 350 tpi brand new in scoggin dicky parts magizine. The motor is rated at 360hp and this is alot more than what my 305 is putting out right now. How hard would this swap be because Iam planing to buy this in dec and have it ready by next spring. To add things up a bit I plan on adding a nitrous express 100 shot. I have a 5spd man trans and I want to know what ill need to change.

 

The real problem is in the computer.If you already have a TPI then the rest will be a straight bolt in.The computer will need to be programmed for the new engine and that is going to be a custom deal.If you don't then the new engine will run like s**t.Also that 5-speed will blow to pieces with that engine.If you don't have tpi then it gets messy.fuel lines and pump,computer,harness,sensors,etc...

 

'89 TPI (which he says he has) is MAF, so it isn't as sensitive to displacement changes as the speed density system is.

The crate you're talking about is their Vortec TPI crate. It includes the Vortec TPI base, but if you read the fine print carefully, you'll note that you'll need aftermarket runners, 52mm TB, and 1-7/8" headers (assumed to be longtube - they aren't specific) to get to that 360 HP. However, they said they accomplished the 360 HP with a stock PROM (probably a stock 350 MAF PROM).

The engine has cast pistons, so I'm not sure I'd want to spray it. I certainly wouldn't want to spray it with more than a 100 shot.

 

So thered be no way that I could safely spray this motor? How would this engine respond with forced injection ie supercharger?

 

You can safely spray it as long as you 1) never let it go lean, and 2) don't hit it too hard (which is why I said no more than 100 shot).

Same story with forced induction - don't go lean, don't push it hard.

Or, take it apart, put forged pistons in it, a little more gap in the rings, and spray/pump away.

 

I dont mean to sound like an idiot but how much extra would this set me back meaning how much would it cost me to do all of what you said?

 

Im sure you could build that motor with forged internals for less than what they sell it for.

 

Well, let's see about that. Let's assume you find a decent roller 350 core, for $150. The crank is turnable, block boreable to .030" over. Rough figures:

Machine work: Assume $800 for tanking, magnifluxing, boring, decking, alignboring, turning the crank, resizing the rods, pressing on new pistons. May be less, probably more.

Parts (From Summit or equiv): $700 for forged pistons, rings, bearings, gaskets & seals, rod bolts, timing set, oil pump, etc. May be less, probably more.

From SDPC:
Heads & intake - Upgraded Vortecs w/TPI manifold: $1270 + shipping.
LT4 Hot Cam - $200
Roller 1.6 Rocker Arms (for Hot Cam) - $310

Assumes your 350 core has usable lifters, pushrods, and tin.

Total: $3,430 (not including shipping) for an unassembled, unwarranted engine similar to the $3700 SDPC Vortec TPI crate. Makes the crate look pretty attractive.

As for the question about putting forged pistons in that crate: Again, ask - they may build one for you with forged pistons for a couple hundred more. Figure on about $400 or so for parts, machine shop work (pressing the pistons), and gaskets for reassembly to do it yourself.

 

hey guys, i just recently put this engine into my car.

i can';t get it to idle right,run right, or anything
it has a total alck of power

1) would the stock computer make it that way?

2) any suggestions on how to make it run betteR?