Changing cam and convertor, what ya think?
10-18-2007, 07:06 PM
#1
Junior Member
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Thread Starter
Join Date: Mar 2006
Location: Baton Rouge, La.
Posts: 15
Changing cam and convertor, what ya think?
Hi all,
Changing the cam and convertor in my car. Here's a rundown on the combo. '69 Chevelle, pump gas, street/strip.
385cid 10.3:1CR 4.040 X 3.750
Brodix IK 200cc 2.02/1.60
Performer RPM Air-Gap Holley 750
Erson 278 solid roller 278/286 238/246 .555/.555 108/104
1.6 in/1.5 ex roller rockers
th 350 3000 stall 4.10 gear 27" tire
3500lbs w/driver
New cam
286/296 256/262 .549/.543 106/102 Solid FT Dynamic CR 8.2:1
Going to put in a 4000 stall. Cam is supposed to pull 3200-6900.
Biggest thing is whether or not that cam will work decently. Intake may get changed to a Vic Jr but so say, the Air Gap isn't giving away much to the single plane.
What's your thoughts?
Changing the cam and convertor in my car. Here's a rundown on the combo. '69 Chevelle, pump gas, street/strip.
385cid 10.3:1CR 4.040 X 3.750
Brodix IK 200cc 2.02/1.60
Performer RPM Air-Gap Holley 750
Erson 278 solid roller 278/286 238/246 .555/.555 108/104
1.6 in/1.5 ex roller rockers
th 350 3000 stall 4.10 gear 27" tire
3500lbs w/driver
New cam
286/296 256/262 .549/.543 106/102 Solid FT Dynamic CR 8.2:1
Going to put in a 4000 stall. Cam is supposed to pull 3200-6900.
Biggest thing is whether or not that cam will work decently. Intake may get changed to a Vic Jr but so say, the Air Gap isn't giving away much to the single plane.
What's your thoughts?
10-18-2007, 09:56 PM
#2
Senior Member
RACING JUNKIE
Join Date: May 2006
Posts: 2,044
The new cam should work well, not sure how much of a difference it will make as both cams are very similar. The biggest improvement you'll notice will be from the higher stall converter.
Changing the intake to a single plane like the victor jr will help upper rpm horsepower a bunch over the dual plane, but it will kill some torque down low. If you go the single plane route I'd go with alittle more gearing, something like a 456 or 488 would be a killer choice for a heavy car like yours and coupled to a single plane intake, you would notice a profound difference in acceleration, however down side is that it would be wound up all the time on the street. I know your limited to camming due to your lower compression for pump gas and streetabilty but bumping it up to about 11 to 1 or 12 to 1 would really wake up your car espcially with a more agressive cam. You have some killer heads already, just missing a couple keys ingredients for a monster engine. I.E< compression, cam.
I know your caught between a rock and a hard place wanting streetablity, and not wanting to get into the expense of having to buy race fuels and then wanting it to be fast at the track too. I know the feeling.
Sorry for writing a book here, first post of the night for me and I'm killing time here at work so there you go. I seen you hadn't had any replies yet so I chimed in.
Goodluck with your new combo, Charles
Changing the intake to a single plane like the victor jr will help upper rpm horsepower a bunch over the dual plane, but it will kill some torque down low. If you go the single plane route I'd go with alittle more gearing, something like a 456 or 488 would be a killer choice for a heavy car like yours and coupled to a single plane intake, you would notice a profound difference in acceleration, however down side is that it would be wound up all the time on the street. I know your limited to camming due to your lower compression for pump gas and streetabilty but bumping it up to about 11 to 1 or 12 to 1 would really wake up your car espcially with a more agressive cam. You have some killer heads already, just missing a couple keys ingredients for a monster engine. I.E< compression, cam.
I know your caught between a rock and a hard place wanting streetablity, and not wanting to get into the expense of having to buy race fuels and then wanting it to be fast at the track too. I know the feeling.
Sorry for writing a book here, first post of the night for me and I'm killing time here at work so there you go. I seen you hadn't had any replies yet so I chimed in.
Goodluck with your new combo, Charles
10-18-2007, 11:22 PM
#3
Junior Member
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Thread Starter
Join Date: Mar 2006
Location: Baton Rouge, La.
Posts: 15
The cam change is what I'm debating. I'd be going from a mild solid roller to an aggressive solid FT. The solid roller is 238 @ .050" and the solid FT is 256 @ .050" but how much of a gain is really there when you add in the area under the curve? Lift values are close.
