Jettech

I’m new the forum but have been doing a lot of reading on engine combos. I have a one owner Z28 and am freshening up the drivetrain. The trans has been done with higher stall and bomb proof updates. Engine is next. I want 400+ torque when done. I have SLP runners that have been cut open and fully Siamesed. I planned to fully port intake and plenum. There is someone that posted a UTUBE video of a 355tpi engine on Dyno making 377 rwt. I’d love to have his engine specs but have been unable to reach him. Does anyone have real dyno numbers with a build recipe or parts list. There is a lot of good info here but without spending months reading everyone it’s hard to get a good parts list.

racerx520

iTrader: (1)

if you do all that work to the plenum and runners, you'll still need to get the air into the engine. you'll need head work, and then you'll need to get it out of the engine, so you'll need better exhaust. from what i understand, 400 tq isnt hard to achieve at a midrange band with these motors, but keep in mind that engines are air pumps. you upgrade the air getting in, you have to upgrade it getting out. your sig doesnt tell us what mods you have already so folks dont know where youve gone with the motor already

Jettech

I have Hooker 2460's with custom Y-pipe and Magnaflow catback. I was panning on ordering AFR 195's for heads unless someone has a better combo. I was thinking of ordering the Edelbrock High Flow intake and port that. My current intake has heli coils in thermostat housing mount points so was just going to replace it. I would like recommendations or parts list for the rest. I do want to keep the TPI and plan on trailering car to TPIS for tuning when done.

Hawgtied

I would go with an aftermarket base like an Edelbrock or Accel. The factory bases don't has as much material that can be removed during porting. You can do some mild porting on a factory intake, but I don't think you would achieve your goal with it. My $.02, I'm sure others will chime in with their experience as well.

racerx520

iTrader: (1)

meant to also mention doing a cam. i use a crane grind #2032 which i understand can be used with the stock heads. If youre upgrading heads, then i'd def go with a bigger cam and heads that can handle it

ironwill

Have you considered building a 383 out of your 350?

Jettech

I have considered a 383 but have heard of combos producing 450+ torque with a 355. I just think if a 355 can do what I want with the rite combo of parts why spend the money for the extra machine work. As far as the intake goes should I be considering the FIRST TPI intake? Thank for the feedback so far...

Hawgtied

A FIRST intake would be good. The other intakes out there (Edelbrock, Accel, etc) are no longer in production so you have to find one used and they are expensive. Then you still need to get some runners. Arizona Speed and Marine has their oversized runners for TPI engines. And you would still need to port the plenum. Getting a FIRST intake would be like one stop shopping. Its an aftermarket base with lots of meat on it for porting, comes with matching larger runners and the plenum is made to match the runners. Contact them to see if they have some available. I know earlier this year he was waiting on a delivery from the foundry where the manifolds are cast.

There is a thread up in the sticky area on this forum that shows actual flow numbers of a FIRST intake vs. some others. I'll see if I can find the link

Hawgtied

https://www.thirdgen.org/forums/tpi/...owing-tpi.html

I think its in here ^^^

racerx520

iTrader: (1)

A 355 still needs to be bored .30 over. and if i remember correctly when i was looking at my options when my engine was swamped by superstorm sandy, a 383 is bored .30 over with a 400 crank. so you wouldnt be paying for extra machine work, but more parts. 383 engines are known for producing a lot of torque, 355 are known for doing just about the same thing as a 350. IMO, if ur spending the time and money to bore it out to begin with, i'd just go 383.
Typically the reason you'd go 355 is if the engine is worn and you need to reshape the cylinder walls you'd bore it out. if the motor isn't worn, then i'd think to just stick with your 350 and build it to make the torque. it is possible i'm sure to hit the numbers you want out of a 350, it honestly doesnt seem that outlandish with a thumpy cam and bolt ons. this is just my thought tho

Orr89RocZ

iTrader: (20)

Those guys hang on the California subsection here and on facebook mollet militia. Heavily modded tpi base i believe, as you need area to make flow on these things. Same with the runners. His video says lunati 280 cam and trickflow heads but i thought they ran the comp xfi 280. Think he went stealth ram as well now but i may be confused. Kevin91z and VincentZ28

if you want 400 lb ft at the tire it will take some work. 383 would be best imo. First tpi i like better for the runner size and length which boosts that low mid range torque spot. Siamese stuff tends to lower peak but extend trq to higher rpm. It could get there but need alot of air flow and some rpm and cubes help.

Did a basic out the box bigmouth tpi setup on a sbe L98 with afr 180’s and hotcam equivalent. Made 351 wtq. More head cam compression and intake flow could raise that, a 383 could add 15-30 lbft too.

ironwill

Your 350 will be out of the car and disassembled to make it a "355" anyway along with new pistons/rings/bearings; just spend the extra $$$ now---while you're doing all this work anyway--- to gain the extra cubes and stroke length that will produce those big torque numbers.

I just don't understand the seemingly common mentality I see almost daily among posters on this site to either pour $$$ into small-bore 305s or not take a 350 to it's much-more beneficial 383 displacement when a rebuild is already planned.


However you decide to proceed, GL.

ploegi

Budget may have something to do with it.

ironwill

There's not a lot of difference in cost between a crank and rods for a 350 and a 383.

If opie is planning on just re-using 30-year-old internals in a build from which he expects to see such high power output reliably, the only other advice I'll offer is.......don't.

Kingtal0n

dont build any engines

Get a used engine with known history from a wrecked car or similar
clean synthetic oil examples
With good compression
Clean it up and perform maintenance (seals) but don't touch the bottom end
Make torque and power from the induction (intake->head->exh)
TPI is a mid-range setup. Use appropriate cam (2800-5200)

Regardless of whether its a 1-piece or an LS variant, don't touch the bottom end
If you don't like the piston or whatever, find a different engine.

Orr89RocZ

iTrader: (20)

The odds of finding aworth while sbc bottom end that will hold higher 300’s whp is slim to none unless you get a great deal on a gen 2 lt1 or maybe a later yr vortec 350. Everything will have tens of thousands of miles on it. You are better off rebuilding with a good shop for a performance engine.

Kingtal0n

man that is sad to hear. In 1989 nissan released a 2.0L that could easily produce 300rwhp and could be tuned to 400rwhp for 20+ years.

1989 they did that.

And in 1989 chevy released a 5L V8 with 160 horsepower instead.

IMO you might as well just go 2.0L in a 2800lb vehicle (11.8 second quarter mile with 320rwhp and 30mpg) If you aren't going to use an LS engine.

At least you won't have to rebuild it just to get 300hp

Motor will cost less than rebuilt and last longer, and its lighter etc
sorry for the wake up call. 300 is 122 cubic inches territory. If you can't do it with 200cubes+ its time to change platforms.
Forcing the owner to rebuild an engine just to get a reliable 300? When you can take a $300 4.8L and get over 700hp from a stock engine instead. Is just crazy.

Lets Look at sloppy's latest:

That is a $200 4.8L engine w/ 250,000 miles or more, making 750hp reliably, just like the other 26 examples in that channel.

As of 2019 I see these are common (well known examples):
1992-2002 2.0L = 300rwhp to 400rwhp nissan
2008-2018 2.0L = 400rwhp to 500rwhp volkswagon
1992-2002 3.0L = 500rwhp to 800rwhp toyota
2001-2007 4.8L = 600rwhp to 900rwhp chevy
2002-2008 5.3L = 700rwhp to 1000rwhp chevy

And those are all stock engines, fragile cast piston applications, nothing special
And then you have this forum, with posts like this, people want to rebuild 5.7L trying to touch 300 or 350, makes me wonder

Orr89RocZ

iTrader: (20)

I’m saying high 375-400 whp na which is what it would take atleast to get 400 whl tq on a 140000+ mile bottom end with worn cam and main/rod bearings and unknown cylinder wall condition is asking for a lot.

Refreshed it can hold it. Boosted it could hold it fairly reliable too. Junkyard motors are gonna be hit or miss here.

wgaf what nissan did with a 2 liter

Kingtal0n

Its just to compare what you get for your money
Might be able to find a nearly complete car 400rwhp 2800lbs 2.0L 5-speed for what it costs to rebuild a junk engine setup from the 90's with any power
I got one for 7k that needed a clutch, I cleaned it up an clutched it and re-sold for $14,500 after driving the tires of it
Theres better ways to spend your money than old V8 engines, which, calling it now: it never gets built right

Orr89RocZ

iTrader: (20)

These cars came with sbc engines and alot of people like them, know them well and want to keep them. There is nothing wrong with that.

Me personally wouldnt build another natural aspirated car unless it was a fun unique setup like a daily driver andi already owned a boosted race toy

some guys spend 100-200k on vipers, supras, gtr’s when a boosted lsx fbody could go as fast or faster for half as much...but different strokes for different folks

VincentZ28

iTrader: (2)

TransamGTA350

iTrader: (2)

The red Z28 in that YouTube video is Kevin91Z on this forum. He, Dyno Don and a number of others are in Southern California and have been working on these TPI builds for a number of years with some excellent results. The genesis of what they are doing is that in California, they are very restricted on modifications due to emissions requirements and required visual underhood inspections. Going to a different type of intake manifold (miniram, HSR, Ramjet, etc.) is not an option for them, so they are working with and heavily modifying the TPI setup. While they are getting great results, it's a whole lot of work and if you don't have the same emissions restrictions, I would be looking at a different type of intake manifold for the horsepower level you are looking for.

This thread, which is also a sticky will tell you more about their builds.

https://www.thirdgen.org/forums/tpi/...owing-tpi.html