It seems as a lot of people here are dissing putting on a TPI for Crate Engines or built up 350's....what's the deal? Some of these engines are showing numbers that produce A LOT of power in the 4200-5200 rpm range...and I know TPI can't breathe above around 4500...but you can't be losing THAT much more power. I just think it's a much more cost affective approach to use TPI, since you can get those manifold's, etc. for very cheap. Someone help broaden this. I'm looking to get a 350TPI Crate from sdpc, or a ZZ4 w/ TPI...Now, how would that be? I'm building a street machine, and it's rarely going to see the track or a strip...so, for street purposes, I'm assuming TPI would just do fine.

I am with you on that observation and am planning on the exact same deal , the ZZ4 is gonna be costly so I might go with the Vortec TPI crate motor with a small shot of N2O. I think an upgraded TPI will be a great street car plus I love the way TPI looks!

I am going to be building a 400 pretty soon, and I plan on using a heavily ported tpi system to help the engine breathe a little better. I will be mostly on the street with limited track time so I think that TPI will be my most cost/gas efficient, and reliable choice. I do plan on hopefully hooking up a supercharger to it, but with only about 6-8 PSI.

You can do whatever you want to, its like everything else in life, there is a compromise made somewhere. Will it run? Yep. Will it make power? Yep. Will it make the most power that engine could if you could run any induction system out there? No.

Well, what do you figure the TPI crate would run w/ a modified TPI induction? Would the ZZ4 TRUELY out perform it? What are your presumptions on the MAX rear wheel power you can get from either the sdpc TPI or the ZZ4 w/ TPI Induction?

There is nothing wrong with TPI for a street engine. If you are concerned with it choking the engine a little just throw a Holley Stealth Ram on it. Considering all things currently available I think TPI with a Stealth Ram is a great choice.

I have to agree, I am going to be using a Stealth Ram on my 383 because of TPIs tendency to choke the motor

I love the price on the complete TPI Vortec crate motor but it is only a 2 bolt main block and pistons and crank are cast . The ZZ4 is 4 bolt and forged so it will be a better block for future mods I belive. If I am wrong someone please inform me. I dont know if I trust hooking up a supercharger to the Vortec crate engine and it hold up to everything.

This is what the ZZ4 Crate motor has
From paceparts.com

And yes, it is a 4-bolt, stronger for future mods, but I would still get better pistons and rods depending on how much boost you want to run

What kind of rear wheel power are we looking at w/ the ZZ4 and TPI Induction? SDPC says the ZZ4 355 is 355 horse at 5250 rpm...Also, that has a different baseplate, so, I'd have to swap that out to make TPI fit, correct? Those numbers don't seem THAT much better than TPI w/ the baseplate already on there. I don't want to get that engine, then have to swap in new parts to beef it up MORE. It already cost almost 4G's...

Opinions?

Yes, you would need to put the TPI baseplate in there. The engine makes that power with a carb. I would suspect that a stock TPI unit would make close to, but a little less power. More torque, though. And your peak power RPM would be lower than 5250.

So, wouldn't it be fair to say...just get the SDPC TPI Crate? The peak horse on that one is at around 4200 rpm...just about where the TPI starts gasping for breathe...I'm sure you could also beef it up to get 350 rwhp...I don't really think you need StealthRam/SuperRam/MiniRam, etc...to get 350 at the wheels for a STREET car. I don't see why I would get a ZZ4, and if I'm going to use TPI, it would hurt performance of THAT engine anyway. Why not stay w/ the TPI Crate, and just beef it up w/ a ported TPI Induction? Wouldn't that get around 400 at the flywheel (330 or so give or take at the wheels)?

I am hoping on 300rwhp with some other modifications to the motor , also a 100hp shot of N2O for an extra kick. Thats why I am wondering if the block will hold out ok.

Sweetride:
If that is all the power you are needing, then yes I would say go with the TPI crate motor and modify it mildly, porting would probably go a long way. Besides, TPI would probably be better for just street use, because of it's low RPM power, you don't have to wind the hell out of it to get the power. Unless you shift a Stealth Ram/Miniram/Super Ram at higher RPMs, you don't see much difference.

LUV:
A 100 shot of N20 on a properly set-up system should be safe for almost any bottom end. There are adjustments you need to make for fuel, and timing. I'm not going to pretend to know the specifics, but you can find those out in the Power Adder forum.

Crew: Thanks for the info. That sounds like what I'll do than. Just find some TPI stuff on the net...then port/polish/etc...What do you think w/ me hangin' w/ LS1 or LT1 guys on the street? Or, possibly smoke 'em (I'm redoing my suspension and everything, so, possibly will have better traction than their stock stuff) Basically, I wanna smoke Rustangs, Cobra's, LS1's (if not keep up w/ 'em), and LT1's at the light...That's how we do around here...lol...everyone goes light to light...So, it's not actually on the STRIP.

I know how it is going from stoplight to stoplight with a newer, and in stock form, better car and beating them. You will have the advantage of low rpm power, after 40 or so mph, when the power band of those newer engines comes into play, they are gonna start pullin you. But, with 350 rwhp in a tpi setup, as long as you got traction, the only thing you should have to worry about is modded lS1s.

Awesome! So, TPI Crate....it's settled. Now, I'm going to get a 700R4 from Pro Built...Street/Strip...Also, w/ a Vigilante Converter (which stall? I was thinking closer to stock so I can get off the line w/o high revs...2000?) I just got a BW 9 bolt w/ 3.27's in it...I'm going w/ a lot of Spohn stuff for my suspension build, so, I should have good power transfer to the wheels. How does that setup sound? 350 doable? I'm just double checking b/c some said it wasn't...

Thanks again man.

for pure street use, that 2000 should be just fine, that setup sounds good to me, don't know why anybody would say otherwise. Have fun

Thanks for all your help man. Really cleared stuff up for me!!!
Can't wait now! :lala:

Also, just to clear up, I'm going w/ the TPI Crate and TPI Induction b/c I have to stay emissions legal here in IL...I would probably do differently, but don't want to risk all the hassel if I won't pass. And, since I have MPFI, modifying my wiring to TPI won't be that hard, and it's all there already. So, doing TPI would be the easiest bet, I would say.

Yeah, I know how you feel, I'm hoping that I can pass with my setup (383/stealth ram), or maybe I will have my car registered in whatever state I get stationed in next TPI will pass emissions easy if you set it up correctly and tune it, maybe I will see you around the NW suburbs sometime?? (When I get back there of course.)

I think I like the TPI Vortech idea too, I really need to get my plan straight before I start throwing my money out! I know my wallet likes that plan alot better then the ZZ4! Thanks for the input also , it has helped me alot too!

I think I'll be happy w/ that setup. As far as my wallet, that's a different story...lol

I should have it all done by May , I need some more money!!!

That's gonna be a great street setup, can't wait to see your guys' results next summer!

I wish I had that outcome planned...to have it done by May...I have to still swap my differential, do my brake upgrade, my suspension upgrades, AND do the engine stuff...I guess I could run another summer w/ my engine, but I just don't want to...lol

Hopefully if the rest get done fast enough, I can start on the drivetrain!!

This is my plan as well (TPI Vortec motor). One of scoggin's tech has it in his car. He also says that this motor is capable of 12.7 with very sticky street tires. Otherwise, low 13's with standard street tires.
This motor will make you turn to your suspension to achieve good times (tons o torq).

More info that's ive compiled..
1 It is a full roller engine.
2 It has not been tested for emissions. It may pass if all other equipment is working correctly.
3 You are correct about the 19lb injectors. Edelbrock uses them in their 350 applications so you should be ok.
4 It was dynoed with 1 3/4" headers but I used the 1 5/8" in my car and the torque is incredible.
5 The heads have .100" removed from the tops of the valve guides and have valve springs that are good to .550" lift.
6 It is the LT4 "Hot Cam".
7 The short block is a Police package Caprice engine.
8 Between 20 and 22 mpg on the highway

Would it be better to go w/ 24lb injectors?
Would my stock MPFI Fuel Pump from my 3.1 hold up after I convert the loom and ECM to TPI?
I think I'll have the suspension covered, so, that's not a big deal. Rearend should be strong enough to hold that power...Trans is gonna be built up....I think now, my only concern is the conversion from my current setup to THAT setup.

I plan to run 21# injectors and get the injector constant changed accordingly in my prom. You can get 21's from fiveomotorsports through ebay for 170.

oh, I wouldn't take a chance with the pump. Change it to a 350TPI pump.

I will have the motor in by May but I am sure there will be those things that will have to be done that I cant think of before its right. I think my rear will hold , my trans is another story but I think it can hold up till the end of next year for a rebuild or replacement. I do have suspension work to do to it but thats not to bad. The exhaust is whats gonna get me too, I plan on a true dual setup with SLP headers and 3" all the way back and to keep it legal high flow dual cats(maybe!).

I definitely have to keep my cats to pass emissions, my rear-end is a 2.73 posi . I don't know what GM was thinking when they put that into Trans Ams. So that will have to go, I am going to put in all new suspension, tubular K-member and lower a-arms, etc. Lots of money, but lots of fun!

24lb injectors should work fine with the right tuning and psi. Make sure you have the adj. fuel press. regualtor

I went to 3.73's which are so much better. I sill need a posi or something. Can the tubular K member hold up to normal street driving? I really dont know and I heard that it might not in a diffrent forum. Let me know what you got on that because if it will I might go with a LS1 instead of the vortec motor.

Once again, hearing from others that you can't get that type of speed I'm looking for w/ the TPI crate. UGH! lol, what to do, what to do.

I love TPI , I think it does require work to get it going good but doesnt everything! I just like the thought of an LS1 under the hood but for cost and trouble I will probably stick with the TPI.

Yeah, don't get me wrong, I would LOVE an LS1 under my hood...and cost doesn't matter, basically, BUT, all the wiring and modding the Crossmember, and all the other mods needed, it's like, what's the purpose? Power, yes, but if I'm getting a crate LS1, I don't want to be swapping parts and tearing into a $6000 engine to get more juice from it. For all the mods needed to make a LS1 fit, it just makes more sense to me to keep TPI. I'm just hoping to hang w/ LS1's when it's all said and done.

Yeah I hear ya, I think I will tuff it out with TPI . I love the design of it even if its not the best or most efficient. I have to convert mine from TBI to TPI still but I read up and its not to difficult just added expense.

What are you gonna put the Vortec motor in anyway? T/A or Camaro?

I'm going to put it in a T/A...there are WAY too many Camaro's I see driving around here...check out my car on the Appearance Boards...Here's the thread:

https://www.thirdgen.org/techbb2/sho...hreadid=210164

That is one sweet Formula. I love the 4th gen seats and console. I wanna get some new Camaro seats for mine. It is one damn clean Formula!

Heres my car

Nice Camaro dude. Thanks for the compliments. I like your racing stripes. So, any more insight on TPI? Did you already order the crate from sdpc? I wonder how long it takes to ship after it's ordered. Your sticking w/ that one, right?

i didn't think that the SD vortec motor made as much power as the ZZ4 with a carb does. If you look on their website the ZZ4 with a TPI intake does not make 355HP i thought it made around 300HP with a TPI intake on it IIRC....i would call them and check it out more...

also if $$$ is not object definately go with a stealth ram, or possibly a modded LT1 intake like the mod of Appearance and Detailing is using....he's metallicamaroRS or something like that....good friend of mine.

Only problem w/ that is I can't use Carb, b/c of emissions...I heard you can make a Carb pass emissions, but I'm not sure on that...plus, I like Fuel Injection. Price is SOMEWHAT of an issue, b/c I don't want to spend TONS on this swap. The sdpc guy in the e-mail told me they GOT it close to 400 at the flywheel, so, I can't see why you couldn't get close to 350 at the wheels w/ that tpi crate.

I havent ordered it yet but i will let you know when I do. I might have to put it on hold but for a good cause. My wife wants a 92 Z and wants to put white stripes on it. She does need a better car she has a nissan sentra now and I hate that little r*** burner. I already have a complete TPI setup that I will put on the 305 then when I upgrade to the SD 350 I plan on dropping the 305 TPI in my truck and just buying another TPI setup for the Camaro.

lol, gotta hate them fart pipes on them things. Sounds like a good plan. I'm hearing that the TPI setup needs a fair amount of work to get that sdpc crate up to par to reach the 350rwhp mark. I don't see it being THAT difficult. Yeah, if you order it before I do, let me know how long it takes. HOPEFULLY, I'll get to it this winter. If not, looks like next winter...But, at least I'll be getting it most likely