z28jimmy

iTrader: (1)

Hey guys I just bought a 383 stroker that was setup for boost and came with 95LB injectors on it and I am looking at running it without boost for a couple years, so my question is can I run it with my stock injectors? Below are the details on the motor:

https://ls1tech.com/forums/parts-cla...oker-sold.html

Here are the engine details
- 9:1 compression
- Custom Comp Cam
- Comp R lifters
- Speed Pro Hell-Fire rings
- Clevite bearings
- JE pistons
- Callies rods
- Lunati crank
- ProGram main caps
- Cloyes timing chain
- Comp retainers, keepers, and springs
- Heads are stock. Ported with 2.02/1.60 valves.
- Converted to 4-bolt main with ARP studs
- Precision Turbo 95 lb injectors
- MSD opti-spark
- Meizere electric water pump

Catmaigne

iTrader: (6)

Unless it has the wimpiest cam ever in a 383, no.

z28jimmy

iTrader: (1)

I believe it is a 218/224 (still working on confirming that). What size would you suggest?

Thanks,

Jimmy

ahritchie

iTrader: (1)

Probably need 30# minimum

Catmaigne

iTrader: (6)

I am currently running Bosch 36lb (more like 34lb in real life) on my 383 but my cam and heads move much more air. I am approaching their limit with a hydraulic roller. I say the 36s minimum. You might be able to get away with the 30s but it all depends on how good the head work was... still leaves no headroom.

BALLSS

FWIW I have a 383 with a Comp 218/224 cam and Ford SVO 30's

The 24's hit 100% duty cycle well before redline on the dyno

30's would be the min size for NA H/C 383 IMHO

z28jimmy

iTrader: (1)

it currently had 95lb injectors on it so would I be able to get it tuned back to run less than 95LB?

Catmaigne

iTrader: (6)

Huh? Any change of injector requires a retune. If the 95lb injector is any good and the tuner is competent then it should run fine. However, the idle quality of a bigger injector is generally less but it varies.

z28jimmy

iTrader: (1)

Sorry for the confusion. I meant to say the motor currently has a set of 95lb injectors on it. Since I am not running boost I was assuming I could not run it with the 95lb injectors. I still need to get the motor installed in my car and get it tuned so I am trying to figure out everything before I install it. So you are saying I should be able to run it with the 95lb injectors with a good tune?

waltsfastz

iTrader: (4)

Why not start to work on a Turbo setup? With 9:1 compression it will be lacking

z28jimmy

iTrader: (1)

I am working on it but it will be some time before I can gather all the parts. I am just trying to get the motor in and run it without boost for about a year or two.

myltwon

iTrader: (1)

I ran 30# svo injectors in a h/c 383 with zero issues 230/242 cam. Also had the same injectors with bolt ons and a 180 dry shot again with no problems. I've seen people run stock injectors on h/c before with no issues (h/c 220s duration ls1 locally that comes mind). From my experience and what I've seen you should be fine with 30lb injectors and might even be good with stockers (though this will depend on the condition of your injectors). A poor condition stock injector will not flow like a fully functional one.

bowtienut

iTrader: (1)

30's is the MAX you would need for a 218/224 cam. I don't care if it's a stroker or not.
24's (stock) will likely do, but unless you have a verified good set on hand, just go with 30's.
100% duty cycle on a datalogger doesn't mean the injectors' fuel flow is at its limit. This subject has been hashed to death already.

hrcslam

Could you elaborate? The subject has be hashed, but what you're saying isn't right from what I recall.

KW Baraka

iTrader: (7)

Back in the old days (1997) I had stock 24LB injectors in my '96 Impala that had a hot-cam'ed 396ci. Car ran/idled great and pulled like a beast at the top end.

I have no idea what the duty cycle was on the injectors, but I do know that the A/F mix didn't lean out at the top of the RPM range.....6300 RPMs or so.

Also.....my injectors were still new(ish), being just a year old.

That being said.....if this were my 383, I'd be going with 30LB (SVO?) injectors.....like the ones that were on my last 383ci .

Jus' sayin'.....


BTW, OP.....I still have those injectors. I'm about to have them refurbished and then I'm putting them up for sale......in case you'd be interested.

KW

hrcslam

I can do the math that proves those injectors work with that cam and 396. Basically though, your peak VE would be 94% assuming peak tq drops off at 4750 (honestly with that cam on a 396, the tq peak rpm and VE would be notably lower) and peak rpm VE would have to be 71% (about right). PE AFRs would be 13:1 in that scenario, all calculations based on ambient SAE conditions. And your injector duty cycles would be maxed out. No margin for error.

I can also do the math that shows 24lb injectors wouldn't work for my 355, nor would 30s, at my current VE and AFRs.

But, that doesn't answer my question.

KW Baraka

iTrader: (7)

I didn't see a specific question in your previous posts......

And not to argue with your 'math'.....my post was based on direct experience in comparison to what the OP is looking to do.....or could do.

KW

hrcslam

My "math" doesn't discount your experience.

As to my question that you quoted. Look at what I quoted when I asked it, you'll understand my question and how you didn't answer it. How is 100% IDC not max flow?

bowtienut

iTrader: (1)

hrc,
I'm sure you've seen these discussions before.
All I can say is direct experience shows there's something wrong with the "math" or reasoning.
Here's what I know: You can wideband tune, have the calculated duty cycle on Datamaster showing 100%, make fueling adjustments and watch the wideband go richer. All of the people getting the most power out of their setups have known this for a decade or two. SVO 30's support 600+ fwhp on NA setups just fine. And I've yet to see one of those fail in extended high power running. Two of us have been running open track events for with SVO 30's on 525 - 550 fwhp setups for 2 years and 10 years respectively. No failures in all those years on the same injectors.
Check out what the fast guys in NHRA/IHRA stockers are doing with small injectors that popular "math" says doesn't work. One of those guys, Gizmo, on this forum can attest to that.

myltwon

iTrader: (1)

Are you accounting for the fact that many injectors are not rated on stock lt1 fuel pressure?