Engine help

dustypowers

Veteran Member
Lifetime Gold Member
Apr 21, 2005
290
Atoka Tenn
I recently rebuilt my 383 and put a solid roller cam in it, after the exchange the car is very slugish and has no torque

combination is as follows

383 30over
alluminum heads 62cc combustion chamber 2.02 intake 1.65exh 180lbs springs
502 lift cam 540 with 1.6 rockers solide roller 280int [email protected] not including rockers
single valve relief pistons 11 3/4-1 cr
2800 stall
4.11 gears

old combination 600 lift hyd 303 lift at duration 11/1 cr every thing else the same


carburetor for both engines is a 650 edelbrock avs other engine had plenty power this one seems to be gutless

any help wood be appreciated as to what could cause such difference when swaping from hydralic flat to solid roller
 

79camaro2001

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Lifetime Gold Member
May 4, 2003
4,792
Monroeville, PA
You could be choking the motor with the small carb.

Only thing you changed is the cam right? Are you sure the rockers are set right? No vacuum leaks?
 

Ga4speedz

Member
Aug 17, 2009
54
Ringgold,Ga
Sounds like the cam may be off. Did you degree the cam in? If the cam is retarted a few degrees it will be sluggish on the bottom end. I installed one cam using a comp cam and timing chain and with the dots lined up it was 2 degrees retarted. Usually they are on the money but it can be off. That's why you should degree the cam in every time you change one.
 

dustypowers

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Lifetime Gold Member
Apr 21, 2005
290
Atoka Tenn
pretty sure the cam was degreed in right

I am curious as to weather a solid roller would require more fuel than a hydralic flat tappet
 

dustypowers

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Lifetime Gold Member
Apr 21, 2005
290
Atoka Tenn
79camaro2001 said:
You could be choking the motor with the small carb.

Only thing you changed is the cam right? Are you sure the rockers are set right? No vacuum leaks?
these were some of my thoughts as well but the other cam was more radical and had the same carb so i am lost
 

MrZeal

Member
Jul 8, 2009
84
Oklahoma City, OK
Just because, how did you decide which keyway to use on the timing gear? I ask because I just installed a Comp three key gear and there are no marks on the keyways to indentify which one is which. I finally figured out that each keyway has a bevel cut into it that I think is supposed to "simulate" a mark: the square keyway represents the square, the 0 keyway is identified by a slight rounding of the top of the keyway, etc. I hope this is right, but I originally installed it using the square keyway, since my woodruff key is square and normal keyways are always square, but that left no way to identify the proper keyway. But I also knew that the #1 cylinder would be at top dead center if it was installed straight up, so something had to be wrong.

It sucks, especially since the two page instruction sheet says nothing about shaped but unmarked keyways, but just says to find the keyway marked with a 0. of course there is no keyway marked with 0. How hard could it be to mark the gear twice, once for the tooth and once for the keyway? Cheap bastards, anyway.

It is possible you may have done what I did, used the "normal" square keyway combined with the tooth marked 0.
 
Last edited:

nova75mike

Veteran Member
Mar 20, 2008
437
Etters, PA
Did you set the valve lash properly? I've known people who go from a 0 lash hydraulic cam to a solid cam (roller and flat) and still set the lash at 0.
 

dustypowers

Veteran Member
Lifetime Gold Member
Apr 21, 2005
290
Atoka Tenn
Rick WI said:
Verify timing at base and full advance and pull plugs to verify jetting.
jetting good base 14, full no vac 34 can't go any higher with my cr

not sure about all the cam a machine shop dialed it for me all i put together was the rotating assembly

also no sure of valve lash this is my first roller assembly what should it be set at
 

Rick WI

Veteran Member
Jul 9, 2001
10,400
Madison, WI
i would make sure the advance is working correctly with a timing light. You also want to make sure when you say jetting "good", you have some feel for why it's "good". Plugs show good color, are they black, no color, heat band at base of insulation look OK?

Just the raw specs on the cam though shows you went smaller on the solid roller. LIft without a doubt and since you don't list the .050 numbers likley the same on duration, or close to it.

From my experience you'd have to have the cam phasing WAY off to have it feel as soggy as it seems in your first post. Just a couple degrees retarded isn't going to be felt at all in the seat of the pants.
 




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