383 built...now need cam suggestions
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Crane site has the 230/238 H-roller which would have been nearly identical to my 232/240 S-roller.
You have to remember that rollers and flat tapped don't act the same for a given .050 duration. With a single plane 383 and 221 cc heads I could floor it in OD and just walk away from most cars at 55 mph. I later on installed an even bigger cam and was very pleased how it drove with my TKO 600
I always used higher ratio rocker arms to get it up to well over .600 lift
It is very easy to change springs with the motor in the car.
You have to remember that rollers and flat tapped don't act the same for a given .050 duration. With a single plane 383 and 221 cc heads I could floor it in OD and just walk away from most cars at 55 mph. I later on installed an even bigger cam and was very pleased how it drove with my TKO 600
I always used higher ratio rocker arms to get it up to well over .600 lift
It is very easy to change springs with the motor in the car.
Last edited by gkull; Feb 9, 2009 at 08:01 AM.
Le Mans Master
Joined: Mar 2005
Posts: 7,631
Likes: 11
From: Rocklin California
Thanks everyone for every bit of input. These numbers are good for future use if the cam I just bought turns out to be the wrong choice. My rationalization for getting this milder cam is because..."been there, done that".
My old 350 had the Crane Fireball 286 flat tappet cam (it's for sale
) with hydraulic flat tappet lifters. Almost everything else was the same as indicated in my writeup at the beginning of this thread. It was lopey (my kids loved that), but rather soggy driving on the streets. I saw only some strip time. So now that I have a 383, I wanted to make it easier and more enjoyable to drive every day in stop and go traffic, which it constantly sees. My mechanic friend, Ron, advised me to start with a mid duration cam to keep the peak power at midrange, not higher as for racing, and the lift at a little over .500, so as not to overburden the springs over time. He said that up tp .530 was ok. LSA at 112 spreads the power curve over a broader range, rather than concentrating it at a certain band. It was tough finding these numbers from off the shelf production cams, since I didn't want to pay extra for a custom grind, and the Crane came close. If I decide that this one turned out to be too wimpy for me, I'll go with LSA 110, a little higher lift up to maybe .550, and possibly a slight more duration up to mid 230's. If that's the case, I'll go with an Isky! 
My old 350 had the Crane Fireball 286 flat tappet cam (it's for sale
) with hydraulic flat tappet lifters. Almost everything else was the same as indicated in my writeup at the beginning of this thread. It was lopey (my kids loved that), but rather soggy driving on the streets. I saw only some strip time. So now that I have a 383, I wanted to make it easier and more enjoyable to drive every day in stop and go traffic, which it constantly sees. My mechanic friend, Ron, advised me to start with a mid duration cam to keep the peak power at midrange, not higher as for racing, and the lift at a little over .500, so as not to overburden the springs over time. He said that up tp .530 was ok. LSA at 112 spreads the power curve over a broader range, rather than concentrating it at a certain band. It was tough finding these numbers from off the shelf production cams, since I didn't want to pay extra for a custom grind, and the Crane came close. If I decide that this one turned out to be too wimpy for me, I'll go with LSA 110, a little higher lift up to maybe .550, and possibly a slight more duration up to mid 230's. If that's the case, I'll go with an Isky! 
Thread Starter
Burning Brakes
Joined: Jun 2008
Posts: 1,194
Likes: 13
From: Seattle area, WA (On the Eastside)
Ken,
That cam was for the Gen 1 ver 1 block with the 2 piece rear main seal that I was going to have rebuilt. It was a pre-87 so that cam is a "retrofit" cam. Now that I went ahead and got the crate 383, which uses the Gen 1 ver 2 post -'87 block with the 1 piece rear main seal, the Thumpr wouldn't work...and also it is too lopey. I decided to go milder for now.
That cam was for the Gen 1 ver 1 block with the 2 piece rear main seal that I was going to have rebuilt. It was a pre-87 so that cam is a "retrofit" cam. Now that I went ahead and got the crate 383, which uses the Gen 1 ver 2 post -'87 block with the 1 piece rear main seal, the Thumpr wouldn't work...and also it is too lopey. I decided to go milder for now.
