It is time for some more ***** nder the hood and I was thinking of ditching the tpi and tossing on a carb but i think there are more cons then pros on the swap. I have a 91z28 with a 350tpi and t56. I getting tired of the tpi running out of air past 4500rpms. I want to get about 400hp for my next buildup and there are so many optionns out there. what are you running for a cam and heads combo? here is what I may go with:

Fast Burn heads and HOT cam
Vortec heads, HOT cam and SDPC base
Edelbrock performer RPM heads, cam?????

whats the best. I think the tpi will be holding back the potenial of the fast burn heads and cam though

 

IIRC , 400hp N/A with TPI is real tough. You'd prolly have to get some AFR heads, but even then with a cam may not help. You might need to go with an LT1 intake, you don't have to ditch the carb.

I could be wrong though.

 

ya a few guys say to get that modified LT1 intake. anyone got more info on it? how would it perform with the hot cam and fast burn heads

 

I would ditch the long runner tpi intake all together.

The low rpm tuning and modest runner size really limits
the horsepower potential.
Since your interested in the vortec heads, you could go for the Ramjet EFI intake that is made for them. You could swap much of your TPI hardware onto this intake. A custom eprom would be nessary if you kept your TPI computer. GM sells the Ramjet
manifold now bare and as a kit with injectors and fuel rails.
Cost will be comparable to getting a Vortec tpi base
and high flow tpi runners. Probabily cheaper.
The outcome would be much, much better.
A moderate Hyd roller like the HOT cam would easily make 400+ horsepower and tons of torque. If you want an alumium vortec head, I would choose the EDelbrock E-Tec 170's for a steet
RamJet/ Vortec project over the Fastburns. The 170cc port will give the best flexability overall up to about 430+ hp.
Only after that will the larger fastburns pull ahead.
An alternative would be to use a modified LT-1 manifold
and either port your TPI heads or get the Edelbrock RPMS
you mentioned.
Once you get away from the long runner TPI intake the rest will be easy no matter which way you decide to go.

 

In Gm High Tehc Performance that has what you need.

The article is titled TPI in a seious way/level. I have it, but can't remember the month. Try to find it.

 

Put something else where the TPI is; or a 100 shot of juice. I'd say get ready to spend a wad of cash, but I don't know that there's anything you could spend any amount of money on that will cure what ails that system as far as getting HP out of it.

 

Simple way? Force feed it. Pick a power adder of your choice, and use it. That'll do it.

 

what kind of numbers will a vortec supercharger add?

 

Depends, how much boost you talkin about?

 

so your saying dont bother with the fastburn heads? which heads are better the E tecs of fastburns? I ask this because I would rather get the better of the two now and have the tpi hold me back then get decent heads now ad then want better later. it easier and cheaper for me to get the best heads now and add small tpi upgrades later.hows this sound:
fastburn heads,hot cam,1.6RR, big mouth intake, slp runners, 58MM TB, ported plenum and mods listed in sig

 

Why go to a head that needs a special intake manifold? I wouldnt bother, just get some good aftermarket heads if you have cash to spend on that stuff.

 

Traxion is running a 12.24 in the 1/4 I'd say he is around 400hp at least

here is a link

http://www.mycar.net/mafb/registry/detail.cfm?id=101

 

You'll also notice he's not running TPI, he's running a MiniRam. A totally different injection system. That's my point: you want your car to go as fast with FI as the same motor will make it go with a carb, you put something on it instead of TPI.

 

Fastburn heads, HSR, 282hr cam, 52mm TB 1 3/4 full headers. Or some 195s or 200s aftermarket heads. TPI s are for stock engines.

 

Nobody recomended the Vortech head conversion setup.

The Scoggin Dickey base with stock Vortechs made 300 horse, with no other mods.

So, that means no TB, no runners, no headers.....you know.

I think that if you do that setup, but cam it, do runners, tb, port your plenlum, you have a chance for 400hp. Don't forget, it's not only the TPI system that runs out of steam at 4500, it's the stock cam, and those L98 heads.

 

If you want to make over 400 hp with a LTR TPI setup, then copy my combo listed in my sig.

:lala: :lala:

Mike (1bad91Z)

 

AND THERE IT IS>

you could probably get away with 9.5>1 compression though.

 

If you want close to 400 n/a horse the cheap way port your stock heads,use the lt4 hot cam and get a stealth ram. Or if your heads are junk get afr 190's with the above mentioned, or vortecs and a miniram III with lt4 hot or similar. Just remember, vortecs/fastburns need a special matching intake.

 

you could probably use fastburn heads and use the ramjet intake manifold just wire the injection system to your tpi ecm. the mini ram does fix the majority of the high rpm issue's with the tpi cars, but you'd be better off fixing it by force feeding it.

 

I have 10:1 forged flatops, but my compression is closer to 10.5:1 when you figure in the deck height of my block and my heads have been milled slightly. You need good compression to make power. You can actually go 11:1 comp. with no detonation issues if you use 93 octane and keep your timing at 6* base timing. I run 93 octane and have my timing set at 8* base and I have no detonation or pinging what so ever! Just my $.02

Mike (1bad91Z)

 

1bad91Z

What kind of gas mileage do you get with that setup? what gearing do you run and what 1/4 mile are you running?

I am looking to copy your setup or the Mike from the 383 TPI string because I am looking for something that will run 13s or less and still get 20+ Highway and 15+ city mileage.

Thanks for the input!

 

all these combo sounds pretty good. My main goal for the winter is to get the cam, 52MM TB, and heads changed. A new TPI setup will come after. My tpi is already opened up quite a bit. I am trying to reach 400hp the cheap way. I know EFI isnt cheap but there has to be a way to do this w/o spending $3,000. Also I want to get a head and cam package that will work with quite a few EFI setups in case I change my mind on things in the future or want to play with different setups. I dont want a cam that works great now and then have to change it downt he road. Hydaulic roller cams are not cheap.Also, I do not want to remove my engine for this 400hp goal and I want to try to use all my igisting mods. is there a better cam grind then the hot cam that makes tons of torque under 5000 rpms

 

Here's a stealth ram for sale on ebay pretty reasonable.

http://cgi.ebay.com/ebaymotors/ws/eB...tem=1874271519

 

If you want to make ~ 400 hp at the crank with-out pulling the motor, you can do it for arround $2,000. Edelbrock has a head/cam/intake package that will accomplish your goal. It comes with Aluminum Victor Jr. heads, Edelbrock lower intake base with runners, and a cam. I would choose a different cam though. For example, my Comp cam works very well. Even comp said that this is the perfect cam for a fully modified TPI motor! I believe that I'm making a little more than 400 ponies though!

I dont have a gas mileage qoute, nor do I have 1/4 mile times, or dyno results, due to I'm still working out all the bugs and have just recently got the new motor running. In fact, I just set the valves and timed it last night! I will post all the numbers after I break in the new motor. First will be mileage (while I'm putting the first easy 500 miles on her), then I'll have it dyno'd, then I'm going to take it to River City Raceway (they dont require cages for 11 sec. cars!!)

This is what I'm guessing though:
17-18 city , 19-22 highway (I have a six speed and 3:23 gears)
350-400 rwhp 375-425 rwtq
11.70's - 12.20's in the 1/4

These numbers could be way off, but from other combos that are close to mine, this should be pretty close for my combo. But, my car is a few hundred pounds lighter and I have way more work in my heads/intake, a little more compression, little more cam, so you never really know until it's dyno'd and raced!

I can say this though, DAMN it sounds good when it's running!! I've only heard one or two TPI cars that sound even close to mine!!

Mike (1bad91Z)

 

Ive been looking at the Holley Stealth Ram intake. what heads and cam work the best with the SR?

 

The way I would build a TPI to get some upper umph cheap would be and Edelbrock 3502 TBI to TPI conversion since you already a TPI no extra BS needed to install. The only thing lacking from this is a TBI- throttle body (needed for this 3502) the best way around that would be a MPFI throttle body from a dodge truck (made by Holley, 1/2 inch tall and has very little restriction. All this for under $1200.