Finally, roller cam installed, first test drive
Thread Starter
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
Finally, roller cam installed, first test drive
Pulled the engine out in January. Left the bottom end together. Pulled the heads to change springs and retainers. Installed a Crower hyd. roller with Morrel lifters (225/232 duration at .050, .536/.551 lift). I'm using Comp 1.52 roller tip rockers, so the lift is slightly higher. I got slowed down with the cam button and custom pushrod length issues but I finally got the engine back in, with steel motor mounts this time. They were problematic fitting over the chassis mounts, but at least I won't have the air cleaner wing nut and stud hitting the hood anymore due to a broken mount. Got the engine running and timed Saturday and checked headlight actuation - no problem. No leaks anywhere, but it was raining so no test drive. This evening I got out to my local testing road, using regular street tires. Definitely more power, especially at upper rpms and it will absolutely smoke the tires from a 15 mph roll now, where as before it would merely spin them. Standing start WOT is like being in neutral, but it did that before. Also, there is no more detonation which I used to get ar part throttle. So overall, I'm happy with the results. The real test will come on June 8 at Englishtown. I will let you know what happens.
Race Director
Joined: Dec 1999
Posts: 11,096
Likes: 990
From: Sierra Foothills CA
That's great Bruce. I was just wondering today how your project was going. It sounds like you'll be flying as long as you can hook up that new found power. Looking forward to a post race report! 
Thread Starter
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
Actually I drive it like the old man that I am most of the time.
Les - I think the new cam won't add much power down around 3K rpm, my stall speed, so I'm hoping it hooks about the same. We'll see.
I bought 4 or 5 buttons. Ended up dimpling the timing chain cover slightly using a bolt which screws into a tapped hole, for this purpose, in my Moroso water pump. This was a trial an error process but got to almost zero front/back movement. I used Manley pushrods. They make them in .050" increments. We used an adjustable testing pushrod and set the length with a test spring on one valve, so the lifter wouldn't compress. We checked at 3/4 of max lift and eyeballed the location of the roller on the valve. I ended up with 7.100" pushrod length. So far, so good.
I bought 4 or 5 buttons. Ended up dimpling the timing chain cover slightly using a bolt which screws into a tapped hole, for this purpose, in my Moroso water pump. This was a trial an error process but got to almost zero front/back movement. I used Manley pushrods. They make them in .050" increments. We used an adjustable testing pushrod and set the length with a test spring on one valve, so the lifter wouldn't compress. We checked at 3/4 of max lift and eyeballed the location of the roller on the valve. I ended up with 7.100" pushrod length. So far, so good.
Thread Starter
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
I don't expect new overall best numbers, due to the summer conditions. But the car was running was running 12.5/12.6 in the heat last year, so 12.3/12.4 would be good now.
It is about time. Since the lifters are reusable, maybe I'll try another cam next year.
BTW - Sorry to hear about your personal difficulties.
BTW - Sorry to hear about your personal difficulties.
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Instructor
Joined: Jul 2011
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From: Boiling Springs
So I'm going to be installing the came with the motor in the car and the bottom end in. Any advice on how to set the end play? Also, with the push rods, how do you know when you have the right size. Last question, did you use the same gas pump push rod, or did you have to use some different one?
Thread Starter
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
So I'm going to be installing the came with the motor in the car and the bottom end in. Any advice on how to set the end play? Also, with the push rods, how do you know when you have the right size. Last question, did you use the same gas pump push rod, or did you have to use some different one?
The end play is a trial and error routine with bolting the sprocket on and putting a button in place, stick the cam in and put the cover on loosely and see if it hits the button. If it does you can dimple the cover there slightly and retry. Slide the cam back and forth with a screwdriver through a lifter hole until it barely moves, maybe .010". Then you need to support the cover. I did that with the extra bolt in the water pump.
The pushrod setup is like I described above. You need an adjustable pushrod (one) and a light spring to replace a valvespring. Start with the pushrod adjusted to equal the difference in flat tappet and roller lifter height, approx 3/4 inch shorter than stock. Mark the top of the valve stem with magic marker, put the rocker on, set at zero lash and turn the crankshaft two revolutions and look at the contact pattern on the valve stem. It should be centered or slightly to the outside.
Had a 1976 L-82, 4-sp
Joined: Mar 2011
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From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
I went with the push rod length that the cam grinder recommended for their HR retrofit cam. It was bang on dead center on top of the valve stem.
Thread Starter
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
If you're using the same brand of cam and lifters, that would surely be the right way to go, or to get very close. I was using different brands.
Advanced
Joined: Feb 2009
Posts: 64
Likes: 3
From: Blairstown NJ
Happy to see you finally got them problems sorted out with your cam swap. Sounds like you won't have any trouble running 11's in good air. Hope to see you at the track, if we ever go racing again!
Good luck...
Thread Starter
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
Thanks. I will make a full report here, good, bad or ugly.