Less power after cam intake and carb change, what could be the problem?

[Chryco Psycho]

ti could just be tuning issues after replacing the cam details are important

[The Cuda Guy]

I have a similar speced cam in my cuda 318.  The car isnt much out of the hole but has great mid range power.  Best thing I could suggest is try to find a part number for your cam and get a card and go from there.  There just seems to be a lot of factors out there for you to deal with.  Cam, intake, carb, gear ect.  good luck.


Don

[Moparal]

Hey baby arm, glad to see your ok   Flew is a biatch huh

[71chally416]

A stock LS-1 motor has a monster cam compared to yours which is one step up from a stock 340 cam, so it shouldn't kill your low end. If the same guy that told you there was no need to cut the Intake surface on the heads did the other work too, then I wonder what else he thought "wasn't important". For instance, if you have stock type non-adjustable rocker gear did you check the heights of the valves to make sure they were equal, and did you check the lifter preload before you installed the Intake? You have shaved heads now so your rocker geometry has changed and you might have to space the shafts up with shims. If you compound that with a bad VJ with unequal stem heights you probably have valves hanging open when you're in it and the oil pressure rises. That would definately make it feel slower.

[Ornamental]

I have a similar speced cam in my cuda 318.  The car isnt much out of the hole but has great mid range power.  Best thing I could suggest is try to find a part number for your cam and get a card and go from there.  There just seems to be a lot of factors out there for you to deal with.  Cam, intake, carb, gear ect.  good luck.


Don

Thanks!  I've tried to google for a cam card, no luck.

A stock LS-1 motor has a monster cam compared to yours which is one step up from a stock 340 cam, so it shouldn't kill your low end. If the same guy that told you there was no need to cut the Intake surface on the heads did the other work too, then I wonder what else he thought "wasn't important". For instance, if you have stock type non-adjustable rocker gear did you check the heights of the valves to make sure they were equal, and did you check the lifter preload before you installed the Intake? You have shaved heads now so your rocker geometry has changed and you might have to space the shafts up with shims. If you compound that with a bad VJ with unequal stem heights you probably have valves hanging open when you're in it and the oil pressure rises. That would definately make it feel slower.

Rocker shims! You might've nailed it there.
I went back to check my emails with the builder, and sure enough, rocker shims were mentioned in an email, "Included in one of the boxes are...   ...10 Rocker Shims".
So basically, I screwed up badly by forgetting about the rocker shims.
Now, if only I can find those damned shims...
Delivering the Chally to a shop tomorrow evening for a little upgrade to be done while I'm at sea.
So I'll have to look around like a manic squirrel on speed, see if I can find those rocker shims and have them installed tomorrow. Good thing that the valve cover gaskets are of the reusable rubber type. And if they aren't, I got gasket on a tube!!

In defense of the builder, the old Performer intake I used with the same heads had no problems at all when installing it. That fitted perfectly, no troubles at all.

[71chally416]

Mancini Racing sells them, and in a pinch I've used plain old round washers I got at the hardware store. They will confort to the shape of the shaft when you tighten them down. The trick is to get them all the same thickness that you need, say .020" or .030". Measure them with a caliper or mic to make sure they are the same thickness.
I like minimum preload. Like 1/8 turn if you are using adjustables. Just enough to keep it from ticking when the motor is warmed up. I don't worry about a little random ticking when the motors cold.   

[Ornamental]

Found the shims, but there were no time to install them. Will do it in about five weeks from now, when I return from work.

[wagesofsin]

always, always, always degree a cam on install....always!!!!