cam question

[Stephen B.]

img001.jpgI was wondering if duke could look at these specs anyone is welcome my 69 running like crap .leakdown test 3cyl above 25% others moderate tore down 3 broken rings 13k on rebuild , pulled out 25 year old rebuild slips cams as shown (69-229-169) ( 61-1121) 61 230hp 69 350/350 is this cam to small for the 350 these were recommended by the shops at the time. are they basically the same shaft? Thanks Steve

[Gene M.]

Re: cam question

Steve,
To be honest I would not select neither one for a street driven Corvette. Both too much duration. Edelbrock #2102 would be my choice.

[Stephen B.]

Re: cam question

Steve,
To be honest I would not select neither one for a street driven Corvette. Both too much duration. Edelbrock #2102 would be my choice.

already in the cars are they basially the same they were built by me years ago probably with bad info the 61 seems to run ok 69 is apart may be time to change it

[Mike F.]

Re: cam question

I just had my 70 350/350 rebuilt using a Comp Cam XE262 cam. https://www.forums.ncrs.org/showthre...no-Runs-Part-2

I wish I had the time and money to try the OE L-46 cam and compare the differences.

[Robert K.]

Re: cam question

Steve, what a blast from the past. It appears to be F284 Crane cam, except the F284 was solid lifter. They both are 284 duration and .453 lift. I've talked to Crane about this cam in recent years. They only have the information you have on the card. This is the cam I put into my first Corvette back in the late 60s. I was told it was too much back then. It was a solid lifter cam. I had headers, a Tarantula manifold and a Holley 780 on a 327/365 short block (11.25 pistons). It was a street driven 12 second machine on street tires. When I returned to college, my mother bought the car off me and removed the headers, cam (replace with a 350/350 hyd) and installed a complete new off road exhaust. She killed the beast, it was at least a second slower maybe two.

My point is that this cam my be too much unless you are modifying the intake and exhaust from stock. Looking at the specs on the piece of paper, the only one with correct cam lift and valve lift is the one circled unless they have some wild rockers. Gotta love that quality control before everything was written in Chinese and translated to English.

[Larry B.]

Re: cam question

230 duration at 50 is not to small for your 350 and did not cause the leak down problems, Detonation more likely broke the rings and caused leak down.You did not say where the compression is at , and the cam and compression must work together.Another problem could be cam degree in if it in early than suppose to be could cause your detonation.

[Stephen B.]

Re: cam question

factory 11:1 pistons so what 10.5 in that ball park

[Larry B.]

Re: cam question

If the block was bored ,block decked ,heads surfaced [.010 thousands makes it about 62 cc]you could be 11.5 to 1 .How much timing total timing not just initial.With todays gas you could be detonating.More cam or at least be sure it isn't advanced.If you are not a purist there are cams to help your problems by moving lobe centers ,overlaps ,etc. you just need to know gear ratios and rpms .