ok the motor details

newly built b18c1 , cp 9:1 pistons, eagle rods , arp head studs, ramhorn , garret t3/t4 50trim , rc550 , walbro 255, tial 38mm gate, tial bov

tuning wit crome

anyway the strange thing that happened last night , been putting some miles on the motor and tuning with crome , datalogging then correcting , been taking it into low boost and afrs were 12:1 and car was driving nice. on the way home i put it under load and spooled the turbo and then let off , i tried to accelerate but the engine bogged down and cut out.

incase i had done any damage i just got a friend and toed the car home, this morning i took the plugs out and looked a bit dark , compression checked the motor and came out 150psi on all 4 cylinders. so put the plugs back in and fired it up. wideband was reading 10:1AFR and then rich (off the scale), plugs were soaking wet.

i adjusted the fuel map to get it to idle but it doesnt sound quite right, and draws less vacuum , 15-20inHg but before it ran 26inHg .

any ideas what would make in run rich all of a sudden ? . would an air leak after the throttle body do this ?? . im stumped.

 

bonk or bump ?

 

did you check to make sure you didn't skip a tooth on the t-belt? running adjustable cam gears? if so make sure they are at correct timing point and didnt slip.

 

will check tomorrow, you think that would make it run rich all off a sudden ? . and still have good compression.

what would a leak down test show that a compression test doesnt ?.

 

check your map sensor

 

well it finally stopped raining so had time to check the car, turns out the cam gear had slipped on the intake cam . was right round as far as it would go on the negitve side.

no damage has been done by the looks of it.
sorted it and put the original map on and the motor runs like a champ.

thanks for help booostboy!.

 

good to hear you found the issue, hope everything is good again.