Thread: Injector Recomendations

Well, Build #2 is just about complete. I'm going to drop the motor in this Friday hopefully.

Current setup:
XP-Cam
CompCam Lifters
Ported Gen 3
Ported TB
Ported Heads
AutoLite 104's
3.25 Pulley
Wideband o2

Are stock injectors good enough for this setup? Does anyone recommend 40#, 42.5# or 60# and why?

btw: No access to E85, I'll be running 93 octane as it's the highest here.

Thanks guys

I ran stockers on basically that same setup...but with ported heads and an XP...you can go plenty lower than a 3.25"...I'd also venture to say I'd pick up the 42.5's...flow matched from Lucas.

I had great luck with them...so have plenty of others and they are everywhere...green tops from Ford are the same thing.

I was able to run stockers down to a 3.2 on a Gen V. The truth of the matter is... watch your fueling and you'll see if you are maxing them out.

Thanks blue and Bill.

Bill, do you mean to watch through hpt or just the a/f ratio gauge?

This will be my first time using hpt, I've read as much as I can about it and looking forward to fugg shid up.

Watch IPW's, wideband would tell but not in the best way. I would go with 42's or 60's depending on what kind of deal you can find.

HPT: 21-22 IPW is static and time for bigger injectors.
If you'd like a rocking config file, send me your email addy in a pm.

IPW doesn't tell you anything by itself.

HPT's VCM Scanner has a parameter already built in to scan Injector Duty Cycle. That is what you will need to scan.

Thanks for that info. IPW's do tell you quite a bit, combine that with WB's etc and you can tell a ton. Duty cycle might not be the end all be all by itself either.

IPW was used back before people knew how to figure IDC when the PT was popular.

When it was in the 20's, the injectors were considered maxxed, even though that was really only half the calculation.

http://www.3800pro.com/forum/fuel-sy...uty-cycle.html

So despite the fact that it may only be half the equation... if the IPWs are in the 20+ range you can consider them maxxed and need to upgrade?

No.

No? But you just said "When it was in the 20's, the injectors were considered maxxed". So is it a yes or no?

Frankly the OP only wanted to know if the stocks would work on his build or if he needed to upgrade. So if at 20+ or higher, if they are close enough to being maxed, if they are in need of being replaced... I would suggest to do so.

The OP clearly states its his first time with HPT, so what would he need to watch for to know?

Question...With my mods in my sig, will the 42# injectors make the engine run way too rich at idle w/o a tune? Just need to make a plan until I get it tuned.

Originally Posted by torq455

Question...With my mods in my sig, will the 42# injectors make the engine run way too rich at idle w/o a tune? Just need to make a plan until I get it tuned.

Yes. It won't run very well at any RPM or throttle position without a tune.

To torq455: you just can't toss in some injectors and expect them to work without skewing the fueling in the PCM via a tuner. It just doesn't work that way.

cant we all get along? everyone calm down

Originally Posted by blueguy91

To torq455: you just can't toss in some injectors and expect them to work without skewing the fueling in the PCM via a tuner. It just doesn't work that way.

I know that. I just wondered how bad it would be. I'm assuming I should only drive it to the dyno like that. I might just put the stock injectors in and swap them out at the shop.

Originally Posted by GTPpower

No.

Hey Bill...why don't you send me an infraction for my post where I corrected you, by posting the correct information, and a valid link. And maybe, title the email, "Posting Junk." Seriously, was that a joke?

The thread he infracted you for was not this one. Just keep it on topic guys, no need to have 10 posts where someone needs to one-up the other. Blue, I'm infracting you for language and ****.

Originally Posted by torq455

I know that. I just wondered how bad it would be. I'm assuming I should only drive it to the dyno like that. I might just put the stock injectors in and swap them out at the shop.

You'll be able to put them in and drive to the dyno. You might notice some driveability issues, but it will make it there.

Local guy had a can and 42.5# installed and the car would not even start till he updated injector tables... Just food for thought... Might have been an isolated case.