Re: Let the fun begin.
 

His fuel pressure rollercoasters up and down with a return line. Returnless systems have problems, but that isn't one of them.

He's fine without a return as long as he keeps the boost low.

Re: Let the fun begin.
 

for now im not planning on running more than 12psi. which i know the car can take since ive run it on 15psi. i just want to get the megasquirt to run properly and have a nice afr.

then the new engine is going in with the gm-8 and 25psi. 400hp and 375 ft/lbs, here i come.

Re: Let the fun begin.
 

Just remember that your fuel pressure @ the rail is going to be pump pressure minus intake manifold pressure.

Most returnless setups seem to run ~55 psi. So, you get more "differential" pressure between the 55 psi in the rail and the -6 psi in your intake during a part throttle cruise... effectively 61 psi of fuel pressure. When you boost it works the opposite... 55 psi rail pressure minus 12 psi of boost = 43 psi of differential pressure. As soon as you add in the return line, expect the tune to go lean at part throttle and rich under boost.

No big deal, just don't press the returnless setup too far.

Re: Let the fun begin.
 

i know that returnless system is limited, but ive been running it for over 3 years now with no explosive consequences so a little longer cant hurt.

Re: Let the fun begin.
 

congrats on the upgrade. what were you running for tuning before? from what i've seen, the management options for foci are overpriced, dealer/professional oriented, and shitty.

Re: Let the fun begin.
 

yup that pretty much sums it up, for a programmer just to flash the ecu it cost 400$ and you cant do any programming yourself. for the software to tune its an extra 350$. and any tuner that uses the sct software charges 300$ for a tune session.

Sct basically controls the focus market. but if i can get a harness made, and simplify the megasquirt process for the focus owners out their. its a fucken huge market.

Re: Let the fun begin.
 

Is your car still ugly like in the picture? And by ugly I don't mean the bondo... :8

I just wish MS had real sequential injection. I just don't like having fuel boiling on the valve for 2x longer than it has to be.

Re: Let the fun begin.
 

Sequential only matters for idle emissions. Everyone on this site is an emissions violator, so that can't be what you are getting at.

Porsche injects fuel between intake events to boil on the back of the valve face for cooling. As such, during engine operation, it is desireable. So, that can't be what you are getting at.

What are you getting at?

Re: Let the fun begin.
 

thats the only little think about megasquirt that it only has two injector banks. which would mean alot of wasted gas. becuase i still do kind of want some decent gas milage.

Re: Let the fun begin.
 

Then don't sit in parking lots idling for long periods, because I assure you gain vs sequential injection isn't a significant differece once you are rolling. Mustang 5.0 got 30-32 mpg on the highway, thanks to the fact there's nothing wrong with non-sequential injection.

I havesome harsh criticisms of MS, but that isn't a blip on my radar.