Hey, ive got a friend who's got a 91 GTA and it just threw a rod. He knows where he can get a 400 small block, But we dont know if his tune port will work on it? Seems like it should be want to make sure first. Also will vortec heads fit a 400?

Thanks.

 

The Vortec heads will fit the 400, but TPI base won't fit the Vortec's.

 

With a 400 I would skip the ltr design and go with an LT1 intake, super ram or hsr. With a ltr you will have huge torq but not upper rpm hp.

 

yes you can make the TPI work on the 400 but stock TPI makes the 400 run out of air fast.

using a aftermarket NON TPI design intake will fix that.... like the stealth ram or LT1 or miniram.


he can put the 400 under his stock stuff for a lil while and then upgrade as he goes, but dont expect it to be faster until he gets everything together.

 

If he has some Vortec heads lined up, he can stay with TPI but he'll have to buy the SDPC vortec tpi base. Port that out, match it to aftermarket runners, and match those to the upper plenum. Every piece of the TPI intake will need porting to satisfy the 400's lungs. If he stays with stock TPI, and just grabs the SDPC base (no porting) that engine will fall on it's face probably @ around 4000rpm! The aftermarket stuff all ported and matched nicely will pull it another 1,000 rpm give or take.

 

if hes making any 400 worthy power, hed run out of air far before that.


not to mention the price of that stupid SDPC vortec base.

 

if you're going to use LTR design on a 400, it would be wise to just get a different set of heads and a set of aftermarket runners (SLP for example) and completely siamese port the base\runners\plenum...you'll lose bottom end torque but you'll have so much losing a little wouldn't hurt and it would help the 400 breath way better.

 

you would be alot happier with a miniram/superram:rockon:/stealthram then you ever will be with a ported stock system.
superram makes peak power at 5800rpms i think and miniram will make power even higher.

 

The 400 would actually respond well to the LTR setup......Get some 220-230cc INT runner heads(Dart Iron Eagle or ProTopline) the TPIS base , runners...and port the plenum....should be PLENTY for the street. Id take a high torque/medium range HP motor over a high revving motor anyday for the street.....now the track is a different story......good luck...just my .02

FWIW, my engine builder built a TPI 400 about 2years ago with the Dart Iron Eagle(220cc) heads, COMP 286HR cam, 24 or 28lb inj, siamesed TPIS base/runners/stock plenum....and the car was in the 11's.....high 11's, and he averaged about 17mpg driving around. He said it never revved over 5500rpm.....guess it didnt need to with all that TQ.....

 

hmm.. im running TPI (granted its not stock, but its TPI) on my 406 and im makign more then enough power.. and thats with out alot of tuning.

 

Those are unbelievable numbers aziroc. What heads, cam and tpi parts are you running?

 

yea no kidding those are huge numbers...tell us your combo.

 

well. in a nut shell.. the tpi is all from TPIS (large tube runners, 58mm TB, and big mouth intake) all those were ported (aka opened up) a whole lot.. and i mean A WHOLE LOT. the heads are also from TPIS. but they are AFR 195's and those were ported/polished, 3 angle valve job and 2.05 1.65 valves. the only bad this is the cam.. i dotn kow the specs right off the top of my head... but i knwo its really small. *try to think about the peanut cams* cuase i wasnt sure on how id do 4 emissions. but when i did get the emissions done.. i damn near 0'ed on everything. so sooner or later ill get that radical cam in there and id think (with tuning) i shoudl be EASILY pull 450 RWHP and 500RWTQ before my 200 shot.

 

aziroc... whats ur peak hp rpm at the wheels?

 

Numbers might be flipped flopped with shorter runners. Either way I agree, damn impressive. Why is this guy only running a 3 speed stick?

 

SLP IROC-Z: i dont remeber exactly.. i got it dyno'ed over a year ago and have since lost the dyno sheets. i know it couldnt have been more then like 5200'ish. but i do remember my TQ started at 2400 rpms and barely moved all the way thru the chart. but since last year i have added alot moere things to the car, so ill prob get it dyno'ed here in november to get soem real #'s.

 

Running a stock TPI on a 406, it will run well up to 4000 rpm and then taper off to 4500, and then even more up to 5000. It acts just like 305 with a peanut cam, only it is acclerating faster thru the RPM range. Be sure your intake has plenty of flow, and run headers and you can get it to run hard up to 4500 RPM before it starts to taper off. Where my 90 IROC runs 0-60, my 406 is just going past 70 in the same distance (IROC shifts at 5500 and 406 shifts at 4500). So with the stock runners, you get a big torque street engine. But if you want big RPM, and plan to run it, then upgrade the intake and heads.

 

what he said
but keep in mind 400's arent really ment to be run at a high rpm (above 6k). grante du can MAKE them go higher.. but most 400's are ment to be in the 2500-5500(6000) rpm range. hence y i stuck with the TPI set up vs a SR or super ram becuase those liek to breathe up past 6k rpms.

 

aziroc,,, Did you ever change back to the "dyno tune" and take the car to the track for better ETs?

 

dyno tune??

no it still mostly like how it was a year ago. i got my motorcycle over a year ago and have been playing with that and the car has basically just sat for a year. i think i put 1000 miles on it total... but now im driving it again. im sure ill get it dyno'ed here soon and see what it can do before i leave 4 the army.

 

My buddy built a 400 with TPI Stealth ram in a 88 GTA. That thing is a beast, no dyno number or ET yet. His car fishtails due to the hard acceleration. Definitely the way to go.

 

A 400 sb will draw 14.3% more air per revolution given the same set up as a 350 so you do not have to run high rpm's to run out of air with a tpi. RPM's has nothing to do with it, it all depends on the draw. If you match the cam and heads to your tpi system then it will work well with a 400 but get a good set of heads and long duration cam and any tpi system with will have a hard time flowing enough to keep up. You may have a screamer up to the time you run out of flow but after that you have unused potential. Personally I would not use a tpi with a 400, it already has tons of torq and I would want the extra flow for more HP.

 

My system works fine...I took the tpi off my 305 and put it on my 400. The fuel levels off at 4500 rpms but I also still have a stock fuel pump. I have not installed my typhoon pump yet. Will see what happens then.

 

so u have the sock 305 tpi on ur 400... stock pump.. and ur sig says u make 450+ hp.. yea time to raise the

 

btw.. where in AZ r u?

 

I got a bone stock 305 TPI on my 383 and it falls on its face around 4500 rpm so I can guess how a 400 would feel. It will work till u can aford to change it but i would recon a Mini/LT1/HSR setup for sure.

As u can see on my Dyno, its a great stop light killer, but need work for highway racing.

 

aziroc
Senior Member

Registered: Oct 1999
Location: avondale, az
Posts: 862
Car: 86 IROC-Z
Engine: 406
Transmission: 700R4


btw.. where in AZ r u?


Somewhere in AZ why? Heres some more for you. The engine was built for 450hp. Sorry didnt list all my engine details in my sig . Since you are a "senior member" I will respectfully bow down and worship at your feet O most holy thirdgenner :hail:

 

I got a bone stock 305 TPI on my 383 and it falls on its face around 4500 rpm so I can guess how a 400 would feel. It will work till u can aford to change it but i would recon a Mini/LT1/HSR setup for sure.


If I cant fix the fuel issue at 4500rpm I will have to consider doing something else. Until then....

 

Made a new sig for my new friend

 

thank you.. its about time :hail:

 

Not a problem...anytime LOL :hail:

 

CaptPicardsZ28:

its extremely misleading for you to say "running stock 305 TPI"


you have bigger injectors, diffrent runners, ect...


the stock 305 injectors wont support anywhere near that HP level.


you have a modified TPI setup.

 

ps, senior member only means you have either been registered for awhile or you post more then a specific number of posts.



it doesnt mean you know dick, it only means you talk alot.

 

SOme people need to learn that HAHAHAHAHAHHAHAHA

Good one

 

But Dan, some of us like to talk alot :P

 

I have a 87 Monte SS that I installed a T-56 6-speed and a 406 with a 1988 IROC 5.7 TPI and converted it to Speed Density.
I have run high rpm motors in the past and for my street car I perfer a torque motor.
I hogged out the plenum and manifold but have the stock runners.
I found that with my roller cam (222.234 deg .500/.501) I run up to 4500 real fast! and the torque is awesome, just what I want on the street. I am still running 24 lb injectors but programmed the computer to run 30 lb.
since I am running the 6-speed with a 3:73 rear my RPM on the hiway drops to under 2000 RPM in 6th gear at about 65 MPH, this gives me incredible torque even in 6th gear due to being fairly close to the "power band" of the motor and I love it!
I built the block and lower end to take a lot so if I want later on I will go to either an aftermarket manifold/runner's etc. or a Super Ram... but for now I am happy to smoke the cars at the lights!
I would agree with (forgot who said it) and put the TPI on (but use at LEAST the 5.7 liter 24 Lb injectors and when you get the money, and IF you want higher RPMs upgrade from there.
Have fun blowing off the import guys!

 

That's funny you have issues with someone else’s signature. Lets talk about yours. What’s with the ETA 12.3 @ 126 mph? Shouldn’t you mention that is a combination of you best ET on nitrous and best MPH on nitrous? In a previous post you took this 399.5 RWHP NA beast to the track and only ran 12.9s on the motor and 12.3 / 12.4s on the spray
https://www.thirdgen.org/techbb2/showthread.php?s=&threadid=148821
Which says---
first time at the track.. have some ?'s
well a few weeks ago i took my car to the track for the first time with members of the car club im in. mind u this is my first time at a strip, with the 406, 150 shot nitrous, and MT E/T streets, 26x11.5x15 on my 15x10 rims. On motor my best was 12.916 @ 106 mph w/ a 1.8 60". On spray my best was 12.3@117 w/ a 1.76 60" and the car bogged in 2nd gear. the run before this i ran by myself and go a 12.4@126 w/ a 1.7x 60". and a major bog.
--------------
Those numbers are a far cry from 399.5 NA rwhp,,, but you said you had made some changes after making the 399.5 RWHP,,,, which obviously were not good for you. I commented in that post that you should change back to the combination of parts that pulled you 399.5 RWHP and take it back to the track to see what number you could get out of it then. My earlier inquiry was just trying to see if you had taken the car to the track and got ets that were more supportive of your 399.5 rwhp numbers.

 

true.. my 12.3@126 is with the 150 shot. on that 12.3 run sicne on that run i didnt have a purge valve let alone a bottle heater. so i know i didnt get all 150 out of it (i doubt i even got 75 out of it) hence the "BEST ETA" in my sig.. hell my first run was liek a 13.3 but agian, thais was my first time at a track. im not the type that is going to make up dyno #'s for what i THINK id be making, N/A or on spray, like other on here like to do, and when u confront them on how they got their numbers..they get all butt hurt and post stupid ****. as far as changes.. yea.. since that run almost a year ago there has ben some better tuning done.. but i have yet to get to the track to see what these new changes has gotten me.. specially since im just now *finally* getting the right suspension parts and ill be able to hook and make my eta were it shoudl be with my MPH.

 

aziroc, you must have the worst traction ever, 126 mph can put you into the 10s easily.

CaptPicardsZ28: shorten your sig, we seriously dont need to know every mod you have done, and definatly dont need to you taking up space thanking Summit, just a lot of waisted space IMO and its freaking anoying



Notice I use the KISS (Keep It Simple Stupid) method in my sig

People dont want to know that I run premium gas, and I have added a TPIS airfoil, and a homemade cold air induction since the last time my car has been at the track...lol

 

(CaptPicardsZ28: shorten your sig, we seriously dont need to know every mod you have done, and definatly dont need to you taking up space thanking Summit, just a lot of waisted space IMO and its freaking anoying)

Oh well, life suks and then u die...hopefully not as a pontiac owner.

 

I am building up my 406 as we speak, but I will be using the LT1 Intake to get me some higher RPM for the track.

As for CaptPicards sig. Nothing wrong with it. As long as people don't attach there sig to everything they post who cares?? My sig is bigger then his for the most part, but I only post it once in a thread. So for Mr. SweetS10V8... Please let the mods do their jobs, and everyone will be happy.

 

CaptPic, you can use the "quote button" down in the bottom right so you dont have to type out, or cut and paste, what other have said already. Just in case you didnt know.




Notice I said IMO? :lala: I just get tired of sigs longer than the posts, and he has posted 3 sigs, one doesnt bug me as much, its just when the info isnt really needed.

 

It also could be that Im writing a term paper on A/C systems and Im on page 18 typed, and not done yet....lol

 

Re: Sigs...I think you can select in the "User CP" function, to post your sig in just the first reply to a thread.

Nothing wrong with a long sig...but as mentioned before, no reason to see it several times in one post

 

Now, no flames but is it my imagination or do the users on here have attitude issues?? sounds almost like the import guys goin' at it!! haha
Be nice to each other.. ya' hear??

 

I believe you dynoed the car and you're reporting the number they gave you. However, in my opinion,,, for what ever its worth (lol) chassis dyno numbers mean squat until you can back them up with a supportive et. I'm not trying to flame you, I'm only trying to point out if you think the numbers were right, and you made changes to the combination and still can't run 400rwhp numbers,,,,,,, you might want to go back to the original "tune" that generated it. Then if you still can't run the numbers,, the dyno was wrong, or your engine is leaving you - which I'd hope not to be true. Anyway,,, best of luck next time at the track. FYI, I'm running the same wheel tire combo. I like running 16psi and have to put a lot of heat into those ET Streets for a good 60ft time - there's almost .2 seconds difference at the 60ft between 20psi and a mild burn. Every little bit helps.

 

[QUOTE]Originally posted by SweetS10v8
[B]CaptPic, you can use the "quote button" down in the bottom right so you dont have to type out, or cut and paste, what other have said already. Just in case you didnt know.


Cool...Thanks! I didnt know that. I am still fairly new here and dont know how to use all this stuff. When I remember I usually only post my sig once per thread anyway.