383lt1impala

iTrader: (33)

hello all i am trying to trace down the problem of why my motor won't want to rev past 5500 while going down the road. it revs to 7000 with no problem in neutral or in park but once in gear its a dog when reaching 5000rpm.


when i was getting it dyno tuned the guy mess with the carb a bit. he said quick fuel had it pretty much dead on and only changed out the primary jets to one step bigger. ran and idled better. and when it came to doing to timing on the msd 6010. he noticed i had a timing curve which was high. something like 36* he lowered it to 31 and ran like doodoo.

so he put the motor on #1tdc marked the balancer and checked the timing with a light a noticed it was reading about 4-5degrees too high. which would explain why the higher curve ran better i was short on funds then so i didn't have him go in it further.

so my question is could it be a sensor issue? which sensor should i switch out? crank or cam? or could it be that the cam degree is off from when it was installed? any help is greatly appreciated. i want to do some research and gain info and do what i can before i take my truck to a shop and have them dig into it

here is the timing curve
20-32* 0-500rpm
32-24* 500-1250rpm
24-29*1250-1900RPM
29-35* 1900-3000rpm
35* from 3000 to infinity.

thats the timing curve i was given or else it wouldn't want to idle and would bog down at lower rpm.


heres a pic of the truck

LilJayV10

iTrader: (39)

Are you using a stock crank? A stock LS crank doesn't have a key way. My SLP balancer has timing marks on it but no keyway IIRC.

I'm asking out of curiosity not because I think you did something wrong.

383lt1impala

iTrader: (33)

its a 383 stroker has an eagle crank. it has a power bond balancer i believe. like i said the guy put the motor on 1tdc and marked the crank took him like 20 minutes to mark it. he would change the timing on the msd box and it would change on the light but they would never read the same degree.

383lt1impala

iTrader: (33)

this is pedal to the floor on the sand. It wasn't tuned then

Here it is on the dyno.


Many have start issues with their 6010. I don't

Darth_V8r

iTrader: (4)

Please forgive what could be a dumb question, but have you considered the possibility of a transmission failure? Could be bogging down the motor? That runs much better in park or neutral might mean something

383lt1impala

iTrader: (33)

No not at all.nbut My trans runs good. Shifts good no problems. I asked around to see if it was a converter problem. But everyone kept saying it's a timing issue. I guess my only real path will be engine tear down rebuild. And if that don't work. New ignition system. And final step new trans and converter.

68Poncho

iTrader: (1)

Where is the fuel pump located? What is the fuel pressure at the higher RPM? Could be starving for fuel.......

Fry_

If it runs better with more timing then give it more timing, it doesn't really matter which number is right as long as it runs good and doesn't ping nothing else matters.

383lt1impala

iTrader: (33)

We went up And down on it. And what is has now is what it likes.

svede1212

iTrader: (3)

The best way to diagnose would be to log with HP Tuners or some other tuning suite like it. Knock, air temp and other things affect ultimate ignition timing deviation from desired. You should have a keyway on the crank and with dot-to-dot or better yet used a degree wheel is how to set physical degree to 0* for the cam timing (different than ignition timing).

383lt1impala

iTrader: (33)

It's carberated. I'm thinking efi for it in the future.