TPI injectors

[Olav]

Hi!
anyone know what injectors that will fit into my TPI manifoil. Will newer GM injectors orther makes fit? I will try to get some 36 lbs or at least 24lbs..... but must what to look after.

[PRRC]

Injectors from a 5.0 mustang is a popular option for the gm tpi. Tim

[Elusive R]

Check out www.thirdgen.org

It's my understanding that LS1 injectors will fit with a bit of careful work. The Ford SVO injectors are also popular because they're relatively cheap and very reliable. Be careful on going too big - 36lbs is probably way more than you'll ever need on a 355. I'm running 30lbs on a ZZ4 and it idles very rich - you can't trim the big injectors down enough to idle close to stoich. 24 lbs would be perfect even well in to the 400hp range. There are some 26lb (maybe 28?) LS1 injectors, but those are rated at 50 or 60 psi, so at 45 psi for the TPI system they'd probably work alright, or you can turn the pressure up and get a little better spray.

Ryan

[camcojb]

You should be able to tune larger injectors. I had 95#ers on a big block and I could make it idle as lean as I wanted. My 05 GTO had 60's with the factory computer, idled easily at 14.7:1

Jody

[Olav]

I have a Haltec computer so I will have some options regarding tuning...

[Elusive R]

You should be able to tune larger injectors. I had 95#ers on a big block and I could make it idle as lean as I wanted. My 05 GTO had 60's with the factory computer, idled easily at 14.7:1

Jody

I agree, you should. But on older equipment, I don't think it works well. I'm on an Accel Gen6 and I'm right on the pulse width lower limit of the injectors (or the system) at idle. If I try to turn it down, the injectors basically turn off and I just get surging. I think newer style injectors would do much better - hence the LS1 suggestion. Maybe a Haltech system would do better, also.

Ryan

[MonzaRacer]

Try dropping your fuel PSi. If it puts too much in on low duty cycle you cna decrease the amount put in by dropping 5 or 10 psi(ie bypass more) .
I agree i have neve had a problem tuning FI with an adjustable fuel preasure regualtor.
Heck we put a TPI 327 together it had a set of 45lb@45psi hr injectors in it and still kept it clean with 1 to 1.5 ms pulse width as we called company that he got them from and we just dropped the fuel down till our O2/pulsewidth came back into range.
Its hard to believe but this is the best way to tune. If your computer program is based 256 blocks then 128 in stoich and we had it running 128/120 BlockLearn/Integrator and a proper O2 reading on narrow band has to go above 800mv and below 200 mv if not your O2 is biased rich and pull fuel. Have to recheck specs on recommeneded wide band O2 readings.
We even used an adjustable restistor pot to get computer understanding the map as the owner had a rather lopey roller. This was one of my first forays into tuning , well before anyone had home means to reprogram it. We have since added a wide band spec to the computer(rechiped),we told it to read wide band over narrow band (its just numbers the processor doesnt know any better)and we readjusted the map specs to live with the lumpy cam.
He now has a better regulator that is boost regulated so it bumps the PSI up when he hits the giggle. The Moded TPI for a 350 has so far bested the dyno with 628 hp off the bottle (he does have some aftermarket aprts in it too!)
And it made 856hp with some go juice.
I love it a 327 and its driveable
Good Luck
Lee Abel
AFTEMARKET PERFORMANCE

[Elusive R]

Try dropping your fuel PSi. If it puts too much in on low duty cycle you cna decrease the amount put in by dropping 5 or 10 psi(ie bypass more) .
I agree i have neve had a problem tuning FI with an adjustable fuel preasure regualtor.
Heck we put a TPI 327 together it had a set of 45lb@45psi hr injectors in it and still kept it clean with 1 to 1.5 ms pulse width as we called company that he got them from and we just dropped the fuel down till our O2/pulsewidth came back into range.

Thanks for the advice. Right now, I'm just stuck with a bad set of injectors *cough* Accel *cough* They cut out at around 1.8-1.9ms. It will idle at stoich now that I'm in Michigan and it's cold, but as soon as it warms up I'll be back to a rich idle. I'll work on replacing the injectors this winter with something smaller since I don't plan on doing anything else to the motor internally.


The Moded TPI for a 350 has so far bested the dyno with 628 hp off the bottle (he does have some aftermarket aprts in it too!)
And it made 856hp with some go juice.
I love it a 327 and its driveable

That's quite a bit of power for anything let alone TPI, let alone a 327. Are you using stock (although obviously modded) GM TPI parts or something like a Stealth Ram?

Ryan

[MonzaRacer]

It is aftermarket replacement larger tpi parts (intake, runnertubes,runner block and throttle bores. Looks stock but runs like stink. We never figured on the numbers either but i had some number very wrong , max boosted number was right at 856 on a 300 shot but it did 578 off the bottle and 628 with a 25 shot dry in front of the throttle body. But still the little 327 made some damn good numbers.
Everyone said it would never run good enough but it ran his Camaro to the best of a 11.28 uncorected ,unfortunately it met it end when a cheap tubular control arm (88 model with unknown brand arms) let go and he scraped a guarde rail for about 3/4 of a mile.
He has since decided to build a first gen Monte Carlo with lots of lightening(carbon fiber dog house, door skins, deck lid and lots of aluminum and titanium (he works in a machine shop)we figured the car had a good 10.85 1/4 pass after we got the chassis dialed in.
Oh and after trading the remains of the Camaro for a 79k original 72 MC I think he got a great deal.
I hope to get some pics of his new ride soon to post here. We may even try to positive preasurization soon as we found a neat little blower with some bearing difficulties (soon to be replaced).
sorry for all the miscomunication but this little jewel does run good and while its still a GM computer it works very well.
Lee