[oldman]

I found out a few things about a full built engine and the SS / LT1 low side fuel system. The stock LT1 low pressure pump is NOT enough to supply gas (much less E85) on a D1X or above type of build even at low boost. The DSX second pump comes in at say 5 PSI, but by that time the LT1 low side can drop as low as 44 PSI (want 60 or above). I know I have the LT4 pump in a box, been waiting to do the shafts all at the same time. So once again, a built engine needs more low side even at minimal boost.

Let me talk about customer service, you only know how good a company is, if you have a problem, in this case, it is my problem with my build.

So I email Dave at DSX, he tells me he will swap out my controller free of charge to one that comes on at 1 to 2 PSI. I tell him, this is going to be hard for me as my two stalls (yes I will add 2 more stalls when I retire) are filled with projects and it is freezing rain outside, so the swap will be done at a shop so I'll just buy one, as I need it on swap day.... He just sends me one that comes in at low boost instead. Wow.

Well the shop swapped the controller, and I subsequent data log still shows a problem with low pressure on the low side. I was working with Dave, but already scheduled a dyno day. Long story short, the shop installed the MAP plug backwards (Dave did some fast troubleshoot via email, I don't think he sleeps ever). So the shop bad, costly, Dave and DSX awesome, fast response, stands behind their work. I still owe him money for the custom low boost controller and time and support, but unlike the shop, Dave and DSX does not even charge me....

So as Pray has been saying "boost" is a measure of backpressue and a built engine is moving a lot of air at no to little boost and at that point the LT1 low side can't hang, so get a controller with a low boost trigger and aslo don't be lazy put in the LT4 low side pump just to be sure.

Oh I did install a red LED to the hot lead of the fuel pump so I know when it comes on, about 1 to 2 PSI...... Low side is great now. Back to a different dyno shop and E85.......

I'm glad I did all this sorting out on the fuel before stepping up on pulley size.

[laynlo15]

I've talked to Dave about his system. He lives in St louis, just about 125 miles from me. That's probably my next move cause I hate 14 buck a gallon VP MS109. Killing my wallet as much as I go to the track.

[oldman]

DSX used to in Austin, he is really a great guy and the product both the pump and the E85 are top quality. The MAP base driver really is the cat's meow, vs keeping it on all the time or the old fashion hobbs switch.

E85 is easy to get in Austin...corn lobby... My ride still gets 20 MPG (on gas) average or so, must not be driving it fast enough......

One other thing to note, we all know you really can't look at the boost gauge, cause you are steering and trying not to die. Now I have a low boost light and a fuel pump on light (one and the same).

A long time ago in my VW I made a signal divider and had LEDS yellow, green and red drilled around my speedo cluster so at a glance I know how much boost.