2 cams...help me choose

I recently ko'd my cam. Engine is 540 BBC big chief 1471 little field HHR 20% OD. In top dragster With PG.

It was
IN Dur @ 50 - 274. EX Dur @ 50 - 282
IN/EX Valve lift .731
IN/EX Cam lift .430
Lobe center 114
1.7 ratio rocker arm

Question is a have recently purchased a 526 BBC BB2 heads little field 1471 HHR 25% OD that runs about the same as above if not a little faster. It has the below cam

IN Dur @ 50 - 288. EX Dur @ 50 - 285
IN Valve lift .823. EX Valve lift .804
IN Cam lift .484. EX Cam lift .472
Lobe center 111
1.8 ratio rocker arm

Which one is the best blower cam or does it matter?

I have 1.7 ratio rockers...does that mean I need to stick with same as I had that I broke?

Thanks ITA!

 

No expert but the one you had, had a better lobe sep angle (114) for a blower. I actually run 116 deg on my deal. As far as the duration and all I'm going to defer that to the people that have more knowledge than me.

Corey

 

Take that 2nd cam and add AT LEAST 6 degrees to the lobe separation and the exhaust duration. If you're more concerned with ET than boost numbers, go ahead and add even more exh.

 

your numbers don't add up right...a .484 lift with a 1.8 rocker will have .871 lift not .823

 

I think he did the lift for a 1.7 rocker as he has them.

 

Cam

Hi Casey,

I'm no cam genius but the 114 degree center line cam is the better way to go, all blown alky cars that I have seen and worked on use either a 114,116, or 118 centerline. The 118 seems to be used more frequently on the screw blower cars. I run a 116 in my hemi but am spinning the blower twice as fast.

I would still speak with Chase at Crane cams even if they are not Crane units, Chase is very smart and seems to be always happy to help.

Best wishes,
Trevor Sherwood