Yellow Bullet Forums banner

1 - 20 of 25 Posts

·
Registered
Joined
·
485 Posts
Discussion Starter · #1 ·
I think i have an idea of what is going on inside this engine of mine but would like to hear what others think is goin on.
These shots are taken after dynoing only.
Engine is 383 Cleveland with CHI 185 heads. 750 Ultra and CHI manifold.
Comp Cams solid flat
666/674
260/[email protected]
Engine still made reasonable power.Not unhappy with the power production at all .
564hp @6650
500 lbs of torque
Cheers,Russ
 

·
Registered
Joined
·
936 Posts
I think i have an idea of what is going on inside this engine of mine but would like to hear what others think is goin on.
These shots are taken after dynoing only.
Engine is 383 Cleveland with CHI 185 heads. 750 Ultra and CHI manifold.
Comp Cams solid flat
666/674
260/[email protected]
Engine still made reasonable power.Not unhappy with the power production at all .
564hp @6650
500 lbs of torque
Cheers,Russ
Well I can make a guess here,try finding out why it is burning oil as that usually is not very good for making power! Dan
 

·
Registered
Joined
·
485 Posts
Discussion Starter · #6 ·
No,the motor does not have ali rods.
And no ,it is not burning oil. The motor sealed up real well and the bores are not glazed.
It may look wet but i took the shot after i sprayed the tops with CRC a few hours earlier so the appearance may be deceptive. They came out dry after the heads were lifted initially.
Focus on the burn signature on the piston.
 

·
Registered
Joined
·
485 Posts
Discussion Starter · #7 ·
Is the piston touching the head?[/quote

No,the slug is 5 thou out of the hole and compressed thickness of the gasket is .041 so we are miles away from contact.

It appears lean around the outer edge of the slug,would you agree?
 

·
Registered
Joined
·
485 Posts
Discussion Starter · #11 ·
x2. Looks like unburnt fuel has washed the piston clean in that area. Being you washed it with CRC though, who knows? What do the chambers/valves look like?
The chamber looks good.
The plug if anything is not showing any evidence of richness either.
 

·
aka hulk
Joined
·
4,965 Posts
I would say you are getting incomplete combustion on the piston,typically you would see this with a big dome piston, and seeing as your piston's are flatops maybe i would look at the chamber design?.......but what the hell do i know!:rolleyes:
 

·
Registered
Joined
·
25 Posts
Intake seal

Are you finding any evidence of oil being pulled in from the lifter valley around the intake gasket? Have the heads been milled as well? The manifold may not be sealing up properly.
 

·
Registered
Joined
·
485 Posts
Discussion Starter · #17 ·
Sorry,definetley not burning oil.
Intake ports are very clean showing no signs of reversion or oil leakage.
 

·
Registered
Joined
·
25 Posts
I'm curious, as I'm currently putting together a 408C combo. Using Iron heads though.

If it's a fresh build, what did you see to made you want to tear into it?
 

·
Addicted To Nitrous!
Joined
·
3,372 Posts
Sorry,definetley not burning oil.
Intake ports are very clean showing no signs of reversion or oil leakage.
I dont know if you are working on the same engine that these pics are of, but there is no question its burning oil., a blind, deaf and dumb woman could see that.:confused:
 

·
Addicted To Nitrous!
Joined
·
3,372 Posts
Didn't mean to come off like an asshole man, but you are definatley getting oil into the combustion chamber, might not be enough for it to show signs out the exhaust, but it is on the pistons. Could be as simple as valve guide seals or maybe the rings didn't get seated properly. The oil in the chamber will cause an irregular burn also. The tops of those pistons should be dry if everything is working right.
 
1 - 20 of 25 Posts
Top