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Discussion Starter #1
I been debating ordering a different solid roller cam to swap out for the one is the engine now . Trying to find out if ---- without pulling engine out --- what specs do i need to look for without running into issues doing a cam swap .
When i bought the engine it had a solid roller already installed . Its a old old cam and has some odd specs that CamKing on here was able to find for me. I fiqured i would try it out ....The specs given were:

the cam is peak at 6,300rpm.
Hot lash is .018"/.028"
Net valve lift(after lash) is .718"/.647"
mechanical roller cam on a 108 LSA
297I: [email protected]", [email protected]", [email protected]"
302E: [email protected]", [email protected]", [email protected]"

The car does ok with the cam but Iam thinking i need something that pulls to the 6800 or 7000 range would be better with the compression and convertor i have .
 

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Get with Jones Cams, he is a member on here. He will get all the specs of your setup and make you a cam specifically for your combo and it will make power for sure. Just my humble opinion
 

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Going to need more info on your motor to get any Cam recommendations


Compression? Heads? Intake? Carb size? all make a difference! car weight trans stall speed? what you are trying to gain? (just RPM?)


Piston domes can get huge at only 468" that could limit cam lift ..... heads are important info as well
 

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Discussion Starter #4
Going to need more info on your motor to get any Cam recommendations


Compression? Heads? Intake? Carb size? all make a difference! car weight trans stall speed? what you are trying to gain? (just RPM?)


Piston domes can get huge at only 468" that could limit cam lift ..... heads are important info as well

468 with 13.1 pistons
heads are Older Grumpy Jenkins that were port and gasket matched -- ill have to look back but think they are 1-043D casting
team g intake - carb is 980 4150 style
turbo 400 w/8 inch convertor
4.11 gear
was 3240 with me last time i checked but have done a few things weight wise . guessing about 3130 to 3150 now
 

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468 with 13.1 pistons
heads are Older Grumpy Jenkins that were port and gasket matched -- ill have to look back but think they are 1-043D casting
team g intake - carb is 980 4150 style
turbo 400 w/8 inch convertor
4.11 gear
was 3240 with me last time i checked but have done a few things weight wise . guessing about 3130 to 3150 now
There are plenty of guys on here that are much better at picking a cam then myself .... but I think you can gain with more @.050 .... I would think something in the 270 range will add a few rpms ..... low .700" lift is pretty standard for a combo lake that one as well!


What does the car run as is?


Really depends on heads tho .... any idea what size push rod pinch is? if there small heads it would hold the RPMs back ..... My guess is that is not your case tho
 

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Discussion Starter #7
There are plenty of guys on here that are much better at picking a cam then myself .... but I think you can gain with more @.050 .... I would think something in the 270 range will add a few rpms ..... low .700" lift is pretty standard for a combo lake that one as well!


What does the car run as is?


Really depends on heads tho .... any idea what size push rod pinch is? if there small heads it would hold the RPMs back ..... My guess is that is not your case tho

Car is not fast by no means , just a toy for now .

It ran 10.97 @124 with a th400 10 inch converter but trans skipped going into drive
Swapped to th400 and 8 inch converter made 2 passes , missed 2nd gear both passes and had surgery sched next day for hand so i called it quits :
The best pass that night was

1.57 60 foot
1/8 was 7.044
mph was 99.89 at 1/8
1/4 was 11.11 at 109.89
shifted at 6100 rpm went into 3rd .. let out before 1/4 cause shift light came on or so i thought .
that was with a 29.9 tall tire
 

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Assuming your engine does make peak HP at 6300 RPM with that cam. You can proportionally raise your peak HP RPM from 6300 to 6900 RPM using a cam with 269-278.5 @ .050", 194-198.5 @ .200" and .785"-.762" Net Valve Lift on a 110 degree LSA.

Performance should be proportional. Good or bad, I don't know. Need all the numbers to determine that.
 

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. Trying to find out if ---- without pulling engine out --- what specs do i need to look for without running into issues doing a cam swap .
The first thing you need to do, is measure your total valve drop at TDC, and 10 degrees from TDC, so you can have a cam designed that won't run into P2V issues.


You will need to put light checking springs on one cylinder. With the rockers removed, put the piston on the cylinder at TDC. Put an indicator on the reatainer, and measure the total valve drop, by pushing the valve down until it hits the piston. Do this on both valves.
Now do the same thing at 10 degrees before TDC with the exhaust valve, and 10 degrees after TDC on the intake valve.


With this valve drop data, you can have a cam designed to mover the power up, without having to worry about not having enough piston to valve clearance
 
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