Running dual 450s. One on a hot wire kit, other on a harness i made with a 3psi hobbs switch. New -8 feed and factory stock as return. Inline fuel filter.

 

That's pretty much my setup also.

 

Hey dude, did that fuel pump (Walbro 450) drop right into the stock fuel tank on your truck? I have an '03 GMC that I'm building a boosted 383 stroker. Planned on doing a new Walbro 255 fuel pump install while installing the new motor.

Thanks

Chad

 

yup dropped right in with very little cutting to get it to fit

 

Sweet, thanks man!



Chad

 

Anybody tried an aem 320 with the stock return regulator? Does it effectively reduce pressure in vacuum like it should or is it too high at idle?

 

with my old walbro 255 my stock regulator was fine I'm gonna say you should be good since its a return style

 

I don't know who makes the AEM so I can't say for sure, but I've seen allot of issues with the 320 pumps. Just a fyi they don't seem to like any ethanol, even E10.

 

Are you confusing them with aeromotive 340 pumps? I have ran plenty of other cars on e85 with the aem 320 pumps (AEM specifically states they are E85 compatible). The 340 pumps are a different story though and I have seen plenty fail with ethanol.

The AEM 320 flows quite a bit more than a walbro 255 so It may not be fine with the stock regulator. If the orifice in the regulator is too small for the pump then the pressure will not be regulated properly and all of your fuel calculations in the ECM will be screwed up. I just have no experience with these stock regulators and the AEM pump.

 

Good point, that may be the case. Just didn't know if they were re labeled.