Long slow MS3X build starting soon

[BlueCuda340]

My fuel system currently is a holley blue that pulls from the stock sender. I don't have any delivery issues with an approximate 450-500HP. Say I added fuel injection and an external walboro pump and made a provision for a return how would this change? I plan on going to a sumped tank anyways but just wondering.

[TheSilverBuick]

I ran a $20 junkyard 5/16th Ford pump in the Skylark for a couple years and then a NAPA $85 new equivalent, but at some point I exceeded the HP ability of the one pump, so I installed a second $85 pump that is staged to come on at a certain RPM. It also added redundancy if my main pump fails on me (yet to have an EFI pump fail on me). In some retrospect there are better pumps in the $120 range that would replace the two pumps I am currently using.

Doing just an external pump with out a good sump or surge tank system would be fool hardy as I tried that in my Thunderbird and right around 1/4 tank it would start stumbling when stopping, accelerating and turning. Added the surge tank with no other changes cured that issue completely.

[milner351]

For more basic power levels - is there anything wrong with an externally mounted walbro 255 or similar pump - should work fine with a stock tank, just need to plumb in a return line? (My stock replacement tank for the falcon came with a 3/8" pick up, and a drain plug - the plan is to eventually use the drain plug for the return line)

[Matt Cramer]

I guess I'll have to see how the modified stock tank works in my truck; it should be up and running pretty soon. It seems to have worked OK for the Nova. Could be we lucked out and the Nova happens to have a pretty good fuel tank for minimizing slosh.

Have you had any experience with the Aeromotive Phantom setup? Does it work as advertised?

[dieselgeek]

One tip I've got is that unless it's a purpose built autocross machine, surge tanks are more trouble than they're worth. My Dart used one and the plumbing was excessively complicated and expensive. On my Chevy C10, I just stuck an in-tank fuel pump on the end of the stock sending unit instead.

That's odd, my customers almost 100% have the opposite experience.

Most of the guys trying to make an OEM tank work have problems under cornering or braking. Literally more than half of them cannot get this right even after installing fancy sumps, pumps, etc.

Meanwhile the guys who didn't want to screw around modifying a stock tank, simply set up a surge tank and had zero problems. Probably 12-15 people I've worked with, can't think of one of them who regretted the surge tank setup. MFI and airplane guys do it all the time, they seem to work ok?

[TheSilverBuick]

One tip I've got is that unless it's a purpose built autocross machine, surge tanks are more trouble than they're worth. My Dart used one and the plumbing was excessively complicated and expensive. On my Chevy C10, I just stuck an in-tank fuel pump on the end of the stock sending unit instead.

I like my surge tanks and cheap fuel external fuel pumps. I've ran the tanks down to maybe a gallon of fuel without issue. The Firebird though may someday get a bolt fuel tank that has an EFI in tank fuel pump, but for now it'll get the surge tank like my other old car converts.

[BlueCuda340]

Thats for sure, that is one reason I started looking into MS.

[milner351]

one distinct advantage to building an MS and then going on dragweek is that you will have some very experienced guys to give you a hand on tuning and trouble shooting.

[BlueCuda340]

I figured if I am going to do it I might as well do the whole thing. It likely will be fuel only at first then move to full sequential. I saw a big block mopar MS3X build where a guy used a jeep cam sensor(which looks like a cut off dizzy on a 4.0) and built a bushing to use it on a big block mopar. I want to do the same with a small block(same style pump drive, should work fine) so that part might take some work and because of that I might go fuel only for a bit. In the end it will look way better than having a whole distributor back there that is doing nothing but playing the role of cam sensor. Just crossing my fingers it will work on a small block.

If I wasn't dead set on doing DW14 I would move it along faster. But I don't have the coin or time to do both. At least it runs and drives at the time lol.

[Beagle]

DIYAutotune has job openings, which I'm obviously not qualified for when I ask this question... what are the compelling reasons to go with a MS3 v. MS2?

just curious. The USB / SD card stuff is intriguing but not enough for me to pony up the bucks for a first attempt, and fuel only at that (edit - for my deal... I see you are going full on crank trigger and all! )

[Matt Cramer]

One tip I've got is that unless it's a purpose built autocross machine, surge tanks are more trouble than they're worth. My Dart used one and the plumbing was excessively complicated and expensive. On my Chevy C10, I just stuck an in-tank fuel pump on the end of the stock sending unit instead.

[BKBridges]

the ez kits are tbi, this is mpefi.. with ign..

Actually, both EZ 1.0 and EZ 2.0 can be set-up as MPI bank to bank. Limitations are at idle. Must have more than 10" of vacuum (low levels of raw fuel) to get em to idle out clean. The new Sportsman set-up is bank to bank but will work with the low idle vacuum (like XFI) and is about 1600.00 with harness and fuel pump pressure control. reqs laptop tuning. Back to the thread...
BKB

[NewEnglandRaceFan]

The MS3 probably isn't cheaper but can do many more things. Not sure about your scenario but the kit you mentioned as well as any of the "EZ" kits likely will not work for my engine.

the ez kits are tbi, this is mpefi.. with ign..

[BlueCuda340]

it seems that there is nothing megasquirt can't do, I look forward to following along - building a set up like this is on my bucket list.

It is going to be a long slow ride but I will post up everything I can.

[milner351]

it seems that there is nothing megasquirt can't do, I look forward to following along - building a set up like this is on my bucket list.