blackws620

I'm about to start my build and I'm not sure if my stock injectors will work or if I need to upgrade.
370CI
243 stg 2.5 heads
Not sure what cam yet but will be a fairly large cam.
Am I running out of injector or will stockers do for a while?

gMAG

iTrader: (1)

What size injectors do you presently have?
Using the Fuel Injector calculator, if you expect up to 425 BHP/flywheel, this would require at least a (1998 injector) 28.8lb inj @ 58lbs delivery pressure @ .80 max duty cycle.
I'll guess and say that with your mods, you'll have way more than 425 bhp.
Again, according to the calculator, up to 525 bhp can be produced with a 36lb inj.
It would be safe to say that you will produce under this amount.
If you don't plan on going higher/more mods, 36lbs @ 58lb delivery will take care of you, with your present intentions.
Some might say to go ahead and order 42lb ers, for possible future upgrades.
Fuel Injector Calculator...(scroll down)
http://www.rceng.com/technical.aspx

slow ride 02

gMAG,

Do you know the rateing for an stock 02 injector?

gMAG

iTrader: (1)

From Fuel Injector Connection (sponsor) post......"they flow 28.8 in the 98 & 2001-up because of the fuel pressure of 58psi.
they flow 26 in the 99-2000, "

blackws620

Its an 01' ws6 so whatever comes stock in it. I think its the 28. Thx for the info.

gMAG

iTrader: (1)

EDIT: I made an amendment to my orig post regarding the definition of BHP (braking horsepower) & RWHP. BHP is measured at the flywheel, and RWHP at the rear wheels (after driveline loss).
If you examine the fuel injector calculator chart, the plug-in value is rated in BHP, not RWHP.
In post #3, I am quoted by slow ride 02. Because the LS1Tech script programming does not also change further quotes, slow ride 02's quote of mine does not reflect my edit of post #2.
Just want to be clear for future readers & the OP.
The bottom line is, that with the OPs mods, I suspect he will have a RWHP/dyno rating of +/- 425>435 hp. Add to this the driveline loss from rear end, tranny, etc, of a minimal 15%, and you have a gross, or flywheel/BHP rating of close to 500hp.
So, again, I would recommend at least a 36lb (@58lbs fuel pressure) injector.
The OPs stock 28.8 injectors will support only 425 bhp, or approx. 370rwhp.
Therefore, the stockers will not be nearly enough.
Same conclusion, just some different language.

slow ride 02

I was told that I am at 88% duty cycle @ dynoed 455 rwhp.

dr_whigham

iTrader: (49)

I'm at 452 and mine were at 100% around 5k. I'd go with some 42#ers and be done.

slow ride 02

Yeah, I was thinking about 36#ers, but maybe I should go to 42#ers?

dr_whigham

iTrader: (49)

You'd be surprised what you can find good ole White Bosch III's for. They came in the supercharged Pontiac GTP's.... They were also used in the Corvette ASA program.

gMAG

iTrader: (1)

Here's some interesting 'gooroo' banter about the Bosch IIIs....not sure that they're the exact same model as Dave has referred to.
http://forums.corvetteforum.com/c4-t...injectors.html

dr_whigham

iTrader: (49)

Good thread. I stumbled on a few here myself before I made the jump. Geoff says theyre a cinch to tune for also, since they're a production injector; Just plug and play with a tweak to the IFR table.

Here's the part # I have 0280155811

They look like this

bristol16

iTrader: (36)

I bought stage 2.5 243 heads and an MS3 cam and with plans to upgrade to a FAST 102/102 in the near future I picked up a set of 42lb injectors. Its better to have them a little too big than a little too small. I have the parts sitting around waiting to be installed when I take the car out of storage next month so I can't tell you how well the setup works, but with the research I did before I bought everything I was looking for something in the 40-50lb range.

Grimes

iTrader: (3)

I actually picked up a set of white injectors. Hope to get them installed this spring.... Supposedly a lot of ppl have used them with success

blackws620

Great information guys! So what are the Bosch White flow? Bristol with the ported heads and ms3 what did your dyno and ET look like with that set up?

Grimes

iTrader: (3)

At our rail pressure, I believe they are 42lbs.

bristol16

iTrader: (36)

Still just a pile of parts right now. I'm going to bolt up everything I have when I take the car out of storage. Might not help much by then but it should be dyno'd mid April, no plans on bringing it to a track though.