hi guys,

i have a 91 z-28 conv. with a newly installed 350 vortec tpi engine from scroggin dickie. also installed where shorty headers, hi flo cat, hooker 2.5" exhaust,24lb injectors, and a holley 52mm tb.

when the engine was installed the transmission (700r4) had been rebuilt with about 5k on it. it shifted just fine and was pletnty firm. (old engine was 305)

i had a 2400 stall converter put in with the engine and a new chip burned. since it was changed and the engine put in, it shifts ok at low rpms, but at wot it shifts at about 7 GRAND according to my tach!!!!!!!! it also shifts like mush at wot. no snap, no screech, just oat meal. i also noticed that the highway rpms are well above what it ran before the change. i still have stock gears, i believe they are 273s. did i mention gas milage sux?

when i mash the gas from a dead stop you get WILD tire smoke, but when it comes time to shift no luck, just mush at 7000rpm. you would expect more from an engine that is suppose to dyno at 357 hp and 416 tq.

i bought a kit with springs and weights in it and had the place that rebuilt the trans to install it. no luck, it may have made a couple of hundred rpm difference if that.

i no someone is going to suggest detent cable but that was checked first and rechecked by the trans place without finding any problems with it. the trans place is at a loss.

please keep in mind it only shifts like this at wot, not normal driving.

ideas? suggestions?

thanks

 

have u tried adjusting the TV cable. that will change shift points. look in the tech articles for the directions

 

thanks, but yes we have. no change. it only does it at wot no other time. VERY frustrating!! the trans place checked that first.

from the response so far i may not be the only one stumped. : (

 

does anyone know if this could be a torque converter problem??????????

i will take a w.a.g. at this point!!:hail:

 

What's the redline of that engine, and at what engine speed does it make its peak power?

 

it has an lt4 hot cam with 1.6 to 1 rockers. from what i have read, with a stock plennum, i should be shifting in the 5600 to 5800 rpm range. i am WAY out of that. i also do not like the wear and tear winding to 7 grand puts on it.

i was talking with a friend and he guessed that it may be a problem with the converter. ideas????????

it may have to do with the 'stock' 700r4, but i don't know.