I have a 351W with Edelbrock Performer RPM alum cly heads, wiseco forged flat top pistons, and a holly 650 double pumper with vac. secondaries running 11:1 compression. What do you think about this cam shaft in my application? lift: intake=538 / exhaust=534 duration at .50: intake=236 / exhaust=242 adv. dur: intake=297 / exhaust=308
I think it should work good, but im not a cam expert, but there are others on this board that are, hopefully they will chime in How about calling the cam manufacturer and asking them just an idea.
My bad this is my current cam. I should have been more clear on that. This cam already broke the springs on a Trick flow twisted wedge cyl head assembly before switching to the Edelbrocks. I was told that I am courting trouble with this cam if I really push the motor.
Just off-hand - it doesn't look like your ramp rates are too steep and the total lift number isn't bad, either. I'm not sure I'd blame the cam for the broken spring.
Rear gears and stall in your C-6 are more important. I was gonna ask about the DP with vacuum secondaries too...LOL!!
If it fits in the block, it's not too big. Yeah, it doesn't quite make sense to have a secondary accel pump on a vacuum secondary carb.
thanks for the advice I was told by some schmuck holding himself out as an expert that my cam was too big. I know that when the builder was breaking in the rebuild on a dyno, he heard a spring breaking. Sure enough, an inspection revealed a busted spring. He felt that Trick Flows were not right for the cam and swapped them for the Edelbrocks. As for the carb, I don't understand the smirks regarding my description. My invoice reads as follows: "Carb - Holley 659 double pump, dual line, vacume secondary Qty: 1, price $369.53." I lifted my description from the invoice. Can somebody explain me what is wrong with my description?
I also don't think it is too big. I'd suspect a simple part failure was to blame and not the camshaft. Double pumpers are mechanical secondary carbs. I have never seen a VS carb with a secondary accelerator pump. It really would not make sense to have a mechanical secondary pump with vac seconds. Many people think that dual feeds make a carb a "Double Pumper" but that only means it is a dual feed. HTH
what I found out Originally, my engine builder had a 4 bbl carb with mechanical secondaries on the engine. However, given the height of my Torker intake, the mechanical carb did not fit under the hood. The builder swapped it for the current carb (vac. secondaries) and it fits. He tells me that when he went into his computer to change the invoice, he didn't completely erase the entry for the previous carb. Instead, he changed the price and made a notation at the end of the part description that it was a carb with vac. secondary.
umm.. mech and vac holley carbs are the same height. the only thing i can think of is that the air filter base may have hit the rear bowl. since vac holleys don't have a secondary metering block, the air filter base would fit then.
also, i would look for a different engine builder because of this quote: He felt that Trick Flows were not right for the cam and swapped them for the Edelbrocks it's certainly not the heads fault for the broken spring (especially since people are running real cams with those heads for ages).
(fingers in my ears) la la la la I can't hear you! stop putting the seeds of doubt in my mind! I want to believe. I want to believe. The next thing you are going to say is that the vac. carb should have been cheaper and not $30 more expensive than the mech. carb and then I am going to be awake all night thinking that........
