SVO 30# Red Top Injectors

[birdie2000]

Read this thread about factory fuel pumps vs. Walbro:

http://ls1tech.com/forums/lt1-lt4-mo...ix-thread.html

If you scroll down to the exchanges between Ed Wright and I, he loves his GM replacement pumps (AC Delco).

I made over 530 NA with my old 383" at the tires through a 4400 RPM non-lock up converter, ran nines at over 135 MPH, and could still make it smoke black at the finish line if I wanted to with the factory fuel pump, lines & rails. Unless you have a lot more than that you are throwing your money away. Spend it on something that will actually make your car faster.

I don't know if I'd buy a new pump or not, might not be a bad idea, but frankly I'd probably just get the AC Delco replacement in your situation. Ed's been tuning LT1s longer than almost anybody.

[mcalus]

IMO, stick with stock injectors, stock fuel pump and drive the thing while you still can, over the winter decided if you want to upgrade them. Plus of you decided to do more mods then you can get a nice dyno tune afterwards.

[hoogiesngrinderz]

I can get you in touch with a guy that has a never used Hotwire Kit.

[alone_and_insane]

I really don't have any intention of upgrading fuel pumps. The question was more to ask whether there was anything to be gained with higher capacity injectors while sticking with the stock pump. I want to make a decision on injectors now and stick with it. Get it tuned once, then leave it alone. I'm to the point where I'm sick of working the car and just want to drive the damn thing. Once it's back together, I'm not touching it for at least a season (if I can get away with nothing breaking). So whatever I decide on now is what I'm sticking with.

I heard back from the guy, he said that he never had them flow matched, so they haven't been, unless they come that way from Ford Racing. If these same injectors are indeed available from Ford Racing Performance Parts, I'm going to see if my friends there can give me a hookup on some. Otherwise, do you think $200 would be a reasonable offer?

[JoeliusZ28]

If youre leaving it alone a while, my opinion is stock injectors are fine.

[nascarnate326]

What cam did you go with?

If Joels car runs fine with stock, perhaps your stock ones will work fine. Save the money towards the next thing that comes up.

[alone_and_insane]

What cam did you go with?

It was in the OP

Lunati 60121 cam - 221/229 duration/ .549"/.565" lift w/ 1.6rr's, 112* LSA
Mild ported heads, stock valves, 176cc intake runner, around 250cfm or so @ .550" lift

Again, just thinking that if it's not a bad upgrade, I would much rather do it now than wait until later. IMO the engine is out now, so there won't be a better time to add things. And like I said previously as well, the yellow plastic part on at least one of the stock injectors is actually broken, so if that's a big issue and that one needs to be replaced, I'm replacing all of them.

[nascarnate326]

Knowing that I would say keep your stock injectors.

[hoogiesngrinderz]

250cfm @ .550 sounds awfully high for mildly ported LT1 heads. AFR heads for LT1 flow around 250cfm out of the box. I'd expect 210-220 cfm for mild port work.

You can replace the O-rings and pintle caps, doesn't cost much.

[alone_and_insane]

250cfm @ .550 sounds awfully high for mildly ported LT1 heads. AFR heads for LT1 flow around 250cfm out of the box. I'd expect 210-220 cfm for mild port work.

[MENTION=1248]birdie2000[/MENTION]?

You can replace the O-rings and pintle caps, doesn't cost much.

Like this? http://www.oreillyauto.com/site/c/de...s%21o-ring+kit

[hoogiesngrinderz]

Yup. Is it the pintle cap or spacer that is broken?

According to the guy I take my heads to, LT1 heads only flow 200-210 cfm in stock form. He said he can get them up into the 260's with a good amount of porting work and a little more if he puts in 2.00/1.57 valves.

[birdie2000]

I consider 250cfm mildly ported compared to the 290cfm AI gets out of their stock castings, plus the intake port is comparatively small also leading me to say "mild," although honestly I said mild to cover my ass on power output of this engine. They do have a full hand port job by Jason Short on LS1tech and have supposedly supported 430rwhp with a CC306 in a 383 stroker in their past life, but this engine will make nowhere near that as it wasn't designed to.

Here's the flow data from a local place I took them to after I bought them. He didn't write down .550" numbers but he said that it went over 250cfm at .550" and then stalled, hence the 242cfm at .600".

Ported Heads - Flow Data.jpg

[alone_and_insane]

Yup. Is it the pintle cap or spacer that is broken?

Um...I'll get a pic tonight

[hoogiesngrinderz]

I wouldn't consider them mild, those are some pretty nice numbers

[JoeliusZ28]

"while the engine is out" really is pretty irrelevant to this decision. You can get to the injectors in less than a minute engine in the car.