View Full Version : 30lb or 34lb?

06-11-2011, 04:06 PM
I'm building a nice L33 5.3 vortec as follows:

243 heads, mild home porting, might skim them 20 thou to bump the cr up from 9.9:1
LS6 intake
heads port-matched to manifold
02-04 LS6 GM cam (0.55 lift) and springs
Ported stock FBW TB
Sheet metal 97-00 'vette exhaust manifold
free-flow mufflers (straight through)
Cold air intake
Mail order tune to start with....

I have LS1 injectors - 30Lbs hr, which can just cope with 400 hp at 4 bar, if this setup will make that much hp....


I could buy a set of 34lb/hr injectors off the 405 hp 'vette (same one that the cam came from) which might give me a bit of headroom, not that I expect to do anything more to this engine.

If I bought the bigger injectors I could always turn down the fuel pressure a bit if idle proves difficult?

Suggestions and guidance welcome!

06-12-2011, 02:40 PM
idle will not prove difficult. get the larger ones. adjust the Injector flow rate, then tweak the other tables (which you may not even need to)