Solid Lifter Cam

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Jeff Seighman

aka jeffnmo
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OK, here we go. My son And I recently rebuilt my 1970 340, about 2000 miles on it now, cam bearings were shot. The engine had 46k miles on it, all new bearings, freeze and block plugs and rings. There was no ridge in the cylinders so I dingle balled them, had some IMM Indy X heads, used some Crane adjustable ductile rockers, port matched the Edelbrock RPM Air Gap with a 650 Edelbrock carb, 800 AVS 2 waiting to be put on. It has a Lunati Voodoo cam, 226/234 @ .050, 494 Intake and 513 exhaust lift, and has Doug's headers. The bottom end is stock, and I have a Hughes 2500 converter in a 727 which I am going to change to a better one with higher stall. I don't know the compression, but I figure high 9's, I can get a gauge and find out. It has 3.55 gears with 28 inch tires. It runs good But I feel like I left some power on the table with my choice of cam, I'm wanting a solid cam and better converter, I'm not chasing power numbers but the more the better, it's a daily driver that is not driven every day! any recommendations? Thanks for any help given, Jeff.
 
Sounds like a pretty good build truthfully. Any work done on the heads? 65'
 
So were the cam bearings shot when you took it apart to rebuild it 2k ago or are they shot now?

If it’s the latter I’d be way more worried about why the cam bearings are toast that quick.
 
So were the cam bearings shot when you took it apart to rebuild it 2k ago or are they shot now?

If it’s the latter I’d be way more worried about why the cam bearings are toast that quick.
They were shot before the rebuild, I found out because I was changing the cam.
 
How much lift are the head/springs good for?
 
OK, here we go. My son And I recently rebuilt my 1970 340, about 2000 miles on it now, cam bearings were shot. The engine had 46k miles on it, all new bearings, freeze and block plugs and rings. There was no ridge in the cylinders so I dingle balled them, had some IMM Indy X heads, used some Crane adjustable ductile rockers, port matched the Edelbrock RPM Air Gap with a 650 Edelbrock carb, 800 AVS 2 waiting to be put on. It has a Lunati Voodoo cam, 226/234 @ .050, 494 Intake and 513 exhaust lift, and has Doug's headers. The bottom end is stock, and I have a Hughes 2500 converter in a 727 which I am going to change to a better one with higher stall. I don't know the compression, but I figure high 9's, I can get a gauge and find out. It has 3.55 gears with 28 inch tires. It runs good But I feel like I left some power on the table with my choice of cam, I'm wanting a solid cam and better converter, I'm not chasing power numbers but the more the better, it's a daily driver that is not driven every day! any recommendations? Thanks for any help given, Jeff.
I feel that you’re caught in the middle some and if you’re looking for more at this point, IMO, you have tipped over into the next set of gear, everything drivetrain wise. You could, as of right now, use more stall and on a cam change I’d look for a cam on a 108 LSA, duration of about 6-8*’s more and then adjust the converter.

Problem is…. Solid cams aren’t readily found in that duration area. The converters re-stalling is expensive and we did t get to the gears yet which is the “Other thing” that will show a bug improvement.

Let me illustrate what I would step up to doing from your combo;

750 or that 800 Carter carb, 3200 converter, 3.90’s and the cam below;
https://www.hughesengines.com/Index...&level2=RmxhdCBUYXBwZXQsIFNvbGlk&partid=30396

This would cruise just about anywhere and do it easy w/reasonable mileage and have very good street power.
It’s also an engine build that I’m gather parts for right now.
 
I feel that you’re caught in the middle some and if you’re looking for more at this point, IMO, you have tipped over into the next set of gear, everything drivetrain wise. You could, as of right now, use more stall and on a cam change I’d look for a cam on a 108 LSA, duration of about 6-8*’s more and then adjust the converter.

Problem is…. Solid cams aren’t readily found in that duration area. The converters re-stalling is expensive and we did t get to the gears yet which is the “Other thing” that will show a bug improvement.

Let me illustrate what I would step up to doing from your combo;

750 or that 800 Carter carb, 3200 converter, 3.90’s and the cam below;
https://www.hughesengines.com/Index...&level2=RmxhdCBUYXBwZXQsIFNvbGlk&partid=30396

This would cruise just about anywhere and do it easy w/reasonable mileage and have very good street power.
It’s also an engine build that I’m gather parts for right now.
Thanks, I was looking at that cam, and am going to call someone about a converter.
 
I should add that I'm not too worried about gas mileage. I've been retired for a while due to a messed up back, and only go out a couple times a month, but I do some highway driving and don't want the RPM's sky high!
 
Yep! It’s up on the shelf with a few others…. LOL

image.jpg
 
I’m not to sure on how a SFT @238@050 would work with those gear & tires. At least off the line. Going down the Hwy it would be close to a boundless top end of just keep on reving and keep on accelerating.
 
OK, what if I went with the 3.91 gears, I would like it to be quick off the line, or what different cam would you recommend, if any? I don't want to go with a shorter tire.
 
What do you think about leaving the cam alone and just going with a good higher stall, from what I've read on the forums here that could make all the difference in get up and go.
 
If sticking with 28” diameter tires I’d go with a 4.10 and once again, the magical 3500 stall. Leave the rest as is.
With the 3.55 and 28” tires, and your max rpm shift points, what does the rpm drop to going into 2nd and 3rd? I’m too lazy to do calculations
 
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I never hooked up my tach after I went with MSD ignition, but I have the tach adapter, it's hard for me to get under the dash but I need to get it done! I looked at a calculator and it says my 28" tires turned me 3.55's into 3.29's, **** I never thought of that! Looks like I should go with at least 3.91's
 
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I went through and reread all the posts, you guys made my brain work again, my engine is probably fine, different gears and a better converter made for my combo, and I think I'll be as fast as I thought I was going to be after the rebuild! Thanks.
 
I went through and reread all the posts, you guys made my brain work again, my engine is probably fine, different gears and a better converter made for my combo, and I think I'll be as fast as I thought I was going to be after the rebuild! Thanks.
I agree, gears and converter...IF you change to a solid FT cam, lash it tight, like .012 hot...beehives don't like much jerk motion so lash them tight if you go that route...
 
I went through and reread all the posts, you guys made my brain work again, my engine is probably fine, different gears and a better converter made for my combo, and I think I'll be as fast as I thought I was going to be after the rebuild! Thanks.
Your combo as listed in your opening post looks good to me but for that converter, followed by the gear/tire combo. But you mentioned you are running 255/60-15’s, correct? Those would be 27” diameter if so. Still could up the gear ratio but a 27” tire is better than the 28” with that 3.55 ratio. Might could start with just a converter upgrade. :thumbsup:
 
I would make sure the tune on that engine was optimum FIRST before I spent more money and labor. WHat kind of ignition curve is in the distributor? Where is the camshaft installed? Was a degree wheel involved?
 
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