SAM98WS6

If not what are you running? thanks

BurnOut

iTrader: (1)

That's what I'm running... the thing to remember is that they are rated at 30 lb/hour at 43.5 psi (3 bar) fuel pressure. At our pressure (58-60 psi) they are right around 36 lb/hour.

StevieZ

iTrader: (3)

I'm running the 30#s in my stroker and the duty cycle is around 70%.

ezss

I had 30# lucas style, which with the LS1 rail pressure are equal to about 36# (PCM is set accordingly). However that didnt seem to be enough and I ended up with 42# FMS (bosch) injectors. Now it seems a bit overkill, because that wasnt really the problem, I guess I got room to expand now.

2001 Pewter WS6

iTrader: (43)

I have the FMS 30# injectors in mine and it is fine.

VSGLS1

iTrader: (8)

I plan on using the SVO 30#s I have now in my stroker.

DG Gordon

Will the stock 01 vette injectors be enough for a 395 stroker. I was told mine are 28.6 or something like that now.

SAM98WS6

No I believe stock 01 vette (99-02) are 26#s..97-98 had 28.8 and that isnt enough.

SAM98WS6

FYI, I posed the injector question to Racetronix since I am using their fuel system. ~600hp NA stroker, 11.0:1, .40 bsfc (race heads), 60psi (400kPa)...and they replied:
600HP
BSFC usually less than ideal to prevent KR
Injector must supply enough fuel at 6500RPM+ big enough to get the fuel in
based on TTI and NOT exceed 80% DC for stable operation.
TTI narrows as engine RPM increases.
30lb @ 400KPa = 34.6lb/hr * 0.80 = 27.7lb/hr
42lb @ 400KPa = 48.5lb/hr * 0.80 = 38.8lb/hr
57lb @ 400KPa = 65.82lb/hr * 0.80 = 52.65lb/hr
These calculations do not factor in lower injector voltage, hot windings,
higher operating pressures, intake wetting, less than ideal atomization, a
hot motor requiring more fuel etc. Returnless systems also drop FP on high
HP motors such as yours which compounds the problem.

42's would be tapped out and Delphi 50's do not work easily in with the LS1
PCM. The Siemens 3172's would be the injector of choice. They are 57#s.

He does not recommend FMS 30#s for optimum performance. I am at least going to 36 or 42. I guess its like using a Holley when you should have put a Demon on...

Reboot

iTrader: (5)

My 30# SVO's are plenty for my setup.

SAM98WS6

Well I decided to buy SLP 36#@43psi..same thing they use in their strokers...for $329..a little cheaper than accel and alot cheap than the 57#s recommended above. About $100 more than 30#SVO. Just to be safe at WOT 6500rpms.

BTW..SLP had steel heavy duty driveshafts..lighter than stock...for $199 on sale. Got one of those in case I twist the aluminum one

Racetronix

iTrader: (2)

If you end up making apx. 525RWHP please post your A/F and max injector DC here.

BTW the Delphi 37's would have been a better choice over the Bosch pintle injectors for less money.

SAM98WS6

Would the Lucas 42#s be an even better choice? They are about the same price. Do you stock the 37# and 42#'s? Thanks.

SAM98WS6

Since you took the time to lend your expertice. I cancelled with SLP. Want to do this right. I will order 37 or 42s from you. Whichever will work easily with my PCM and fuel 500rwhp.

Pro Stock John

iTrader: (34)

I ran GM GTP injectors, which were like 38's @ our FP.

I would run a 36 lb injector for a big inch motor, not 30s, the 30's will be running at a high duty cycle.

I'm with Jack @ Racetronix, I would run the Delphis.

Racetronix

iTrader: (2)

IMO most savvy experienced HP tuners use injectors slightly larger than required to keep injector timing stable / low DC's and provide room to grow. Buick GN owners have known this secret for over 15 years. It is not uncommon to see a fairly stock V6 3.8L motor using Delphi 42 or 50lb injectors with factory like idle and drivability. Fortunately the caliber of Buick V6 tuners is vastly better than the GM V8 tuners. Most GM V8 tuners try to stick with smaller injectors as they constantly have trouble tuning AE, idle and general drivability with larger injectors. Most tuners are able to tune WOT easily enough on a DynoJet but are unable or unwilling to spend the time on drivability on the street. DynoJets although popular are not well suited for drivability tuning with their friction brake. Most dyno shops don't even know how to or have the means to use this feature. This is where dynos with PAUs such as the Mustang, Superflow etc. start to shine. If you have a good tuner in your area that is really good then go with the larger injectors but if you are going to rely on the forums and less experienced tuners then perhaps the smaller injectors would be easier to deal with.

Flame suit on <CLICK>

Spinmonster

what is the side effect of too big an injector?

Racetronix

iTrader: (2)

With SOME large injectors the PW can not be made narrow and/or stable enough to maintain the required A/F at idle & part throttle.

The size range of injectors that we are dealing with here are not of issue. It all comes down to the tuner.

Spinmonster

Thanks Racetronics and your fuel pump in my C5 is awesome