Quote Originally Posted by AggieTJ2007 View Post
The worst problem was that the motor would run great for a short period of time but when we started driving down the road to the course at around 2000 rpm the motor would start to backfire badly and you had too keep the RPMs up around 4000 rpm just so you could drive down the road. It always seemed to stumble around 2000 rpm.

Also when we pulled the air filter to build the snorkel it was evident that the motor was only backfiring through one TBI I believe that it was the rear one.

Also how did you set fuel pressure with the fuel pressure gauge on the high pressure (inlet) side of the fuel pressure regulator
As stated before it is most likely a timing issue, the intake back fire is do to an advance issue not a lean issue. Everything will be workout in the end. What also has to be realized this motor has 2.30" intake valves, a limp dick cam, and 8:1 compression, the plan was to eventually go to a stroked motor thus the reason for the giant valves. Like any new idea it takes time to work out the bugs, and with Flem being the only one of us with the equipment and ability (which is a lifesaver) and the fact the me him and sharpe, were driven into the ground trying to finish everything else om this truck just to get it worthy to go out there, the motor got the best we could give it.

As for the fuel pressure, pressure is regulated on the return, thus the reason the guage is on the inlet, just like almost every FI vehicle on the road