M30 Swap - Drivetrain Bucking Issues

[chrisherrel]

Hey R3V - been posting in the classifieds over the years collecting parts for my M30 swap and have everything installed in the car and have the motor running great.

Unfortunately, as the project has gone on, I've lost the time that I used to have to wrench and have had the car through two shops here in the Cleveland area that have got me to where I am today, but not all the way across the finish line.

Putting the car in gear and getting it going using just the clutch is relatively smooth, but putting it under any sort of additional load in any gear causes the entire car to buck violently (except for a slight smooth portion in the 2k-2,750 rpm range). It feels similar to if you were coming to a stop in 5th gear without the clutch in. I've fought the car through the gears (tried short shifting and making my way higher in the rev range) and encounter this issue in all forward gears. There aren't any grinding or whining noises that would lead me to believe this is an issue in the transmission or rear axle - so I'm thinking it's down to some sort of clutch issue.

Has anyone encountered similar issues in the past? Hoping to benefit from the collective knowledge and community that has been a mainstay through my time interacting with R3V.

Thanks,

Chris

[MrBurgundy]

look into ignition issues (spark)

usually under load it will fail, which is why under light throttle its not doing it.

[McGyver]

my guess would be spark, fuel, or engine management related.

double check plug wires, connections, order on the distributor. Verify correct FPR pressure is being used, correct sized injectors, sufficient fuel pressure. try swapping the DME and AFM to see if that helps. make sure you don't have a sensor unplugged.