injector question

**Balaska347** · 12-25-2007, 11:52 AM

Does anyone know how much RWHP 30 lb injectors can handle on a NA combo?

**speedracer** · 12-25-2007, 12:05 PM

Originally Posted by Balaska347

Does anyone know how much RWHP 30 lb injectors can handle on a NA combo?

I used a injector calculator and it came up with 400hp but it dosn't say rwhp so I'm going to assume thats at the crank and if you subtract 17% drive train loss you get 332rwhp

**phillysrt4** · 12-25-2007, 12:40 PM

stang N/A noobs like me shouldnt post numbers.

**349Stroker** · 12-25-2007, 05:22 PM

WAY OFF!!!!!

I had 435 rwhp in my old coupe with 30's and they were just fine.The car was actually rich on the a/f

**phillysrt4** · 12-25-2007, 08:23 PM

Originally Posted by 349Stroker

WAY OFF!!!!!

I had 435 rwhp in my old coupe with 30's and they were just fine.The car was actually rich on the a/f

curious, what was the setup?

darn na throwing off calculations! (even though you said NA I used a forced a typical forced induction BSFC for my calc) :P

**fastfox91** · 12-25-2007, 08:29 PM

30s can support way more than 325 on a n/a engine i seen the car whlstnder is talking about and 30s were more than enough

**349Stroker** · 12-25-2007, 08:33 PM

349

Track Heat Stage 2 heads

TFS R intake

Stage 3 cam

30's & 95mm Pro M

G Force 5 speed

4.30's

28" tire

I tuned it with a pms and lleft it rich.I sold the car and the guy took it to Englishtown and went 11.0's.He went to Big Daddy Performance and it made 403/407 @11.3 a/f.They leaned it out to 12.0 and made 435.They took it to the track and it went 10.78@128

**Pure Stock** · 12-25-2007, 06:53 PM

Originally Posted by Balaska347

Does anyone know how much RWHP 30 lb injectors can handle on a NA combo?

Here are two real-world, proven, record setting, EFI combos:

Ex.1 N/A 310.7 c.i.d, GT-40 heads, Cobra intake, tuned with EPEC. 363 RWHP Utilizes 24 lb. injectors.

Ex.2 N/A 302 c.i.d., TFS heads, Holley SMII, untuned. 374 RWHP
Utilizes 30 lb. injectors.

There is definitely some room to grow in the 2nd combo. Volumetric efficiency, BSFC, and other considerations need to be examined when selecting injector ratings.