Hi everybody,

I did that popular swap (305 to 350) and put a set of 26lb/h injectors on top of the beast. I changed the injector size in my prom (730 $8D) but do I need to change the PW? (new PW = (old ratio/new ratio)*original PW right?)

thanks a lot.

 

The injector size is the only thing that would be changed in this case. The final outputted pulsewidth is determined by the engine/intake air temp, MAP, baro, engines volumetric efficiency, cylinder size, etc. Its likely that youll also have to tune the VE tables as well so you get the correct fueling.

 

Thanks for the answer.

I'll make a new bin this WE, using a 350 VE table and put it in a 305 bin (because my car was previously a 305 TPI with a T5, I prefer adapt that stock bin with 350' VE ) I'll also adapt inj size, and lower timing because I have a bit of detonation. I'll flat timing curve close to 0 and start re-tuning my fuel. As soon as I can get the BLM close to 128 in almost all situation, I'll start playing with timing. I guess that's the easiest way to proceed.


I have a side project also. I'd like to run with E85 (wich is about to become popular here in France). So once I feel comfortable playing with beans I'll start working on a new bin with a AFR close to 10.6 to run E70
and another one with AFR close to 9.625 for true E85.
I don't know if you have the same thing in US (When I lived in Philly few years ago, nobody heard about E85 at all) but in France the E85 sold in gas station is only a E70 (70% Ethanol 30% fuel)
But anyway, this work will lead to another post.

once again, thank you very much.