hey so i rebuilt my gsr with npr pistons and rings. im running 180cc injectors(i thought they were 235cc)it is untuned. so i started it up and it ran fine for about 75 miles. spark plugs went white because of the lean air mixture. so with this in mind #1 cylinder is at 185 and the rest are at 85. valve adjustment has been done also. so now when i drive the car it drives fine, except for if i shift a little too slow the car like shuts off, and when im going down a hill at like 25mph in 3rd gear and like let off the throttle you know how it will jerk, well it like jumps around 1 to 3k trying to stay on and the car like jerk and dies. my thoughts are that since the clyinders aren't sealed, when i do this to the car it tries to create a lot of vacuum because of the load on the engine but it cant make enough vacuum to run so it dies. the car also idles fine except for when the fan comes on cuz im running a 4channel amp then it like fluctuates by about 200 rpm. what do you guys think

 

185 psi on cylinder 1, and the rest 85 psi?
That itself is a problem...
Find out why you have low compression first. This is your biggest concern at this point...
Do a leakdown test to diag where all your compression is going...Driving 75 miles untuned is not good either...