good specs forBLOWER cams ???

[vinces427bb]

looking to see what worked and didn't for boosted blower engines;
i've used 3-cams so far;
1- on a 112LSA hydro-roller with 225*/231* @0.050 & a 0.567''/0.578''
Good = pulled super hard with 15#boost,
Bad = floated valves @ only 5800-rpm

2- on a 114LSA solid-roller with 240*/250* @0.050 & a 0.570''/0.570''
Good= not so much....
Bad= never ran worth a damn, had many valve train issues
would not build over 10#boost?
still not sure if it was just a bad cam or WTF...

3- on a 110LSA solid roller with 230*/238* @0.050 & a 0.629''/0.629''
Good = runs nice rev's hard with fair idle
Bad = would not build over 10#boost with out a pulley change
think it has alot less restriction and flows mucho air...
after 2-pulley changes it is maxed out on blower rpms and the boost is 12+pounds.
haven't been able to get a good look, hanging on the steering wheel keeping the car straight

went with the 110LSA to get a better idle sound,
But i would like a Tougher Idle sound with the performance of cam #1 and more rpm range...

[vinces427bb]

well nobody shared their secret cam spec's with me so.....
i contacted Chris Straub, www.straubtechnologies.com for a better lumpy stik...
it's a custom grind, i'm told it will be at least 100-hp better that my firstcam that ran super hard.
now all of the work to swap it over.

[Michael]

Unfortunately, I don't have a lot of hands-on experience selecting a blower cam, otherwise I would have chimed in a long time ago. I normally just provide all the information specific to my engine/blower setup (and intended vehicle use) to the professionals and go with their cam suggestion. Hopefully Chris Staub's suggestion provides the expected power increase, but more importantly doesn't suffer from any of the issues you've experienced with the other cams you've tried.

Will this new cam also require (or benefit from) a change of valve springs? Springs with a higher seat pressure than those you're currently running might help reduce some valve float you may experience at higher RPM.

Keep us posted after you swap the cam to the new grind. It'll be interesting to see if you get the expected power increase.

[vinces427bb]

Yeah i was looking for a cam with spec's somewhere between #1 & #3 (closer to #1) but was not sure on the duration split and lift split.
the springs i'm using are 200#seat press @ 1.900''. this is sufficient for my application.
i provided the spec's on my engine,drivetrain,car so Chris could select the best cam.
i was using the cam companies listed to help pick the #1-3cams, but as Chris told me, none were even CLOSE...
Chris has spec'ed cams for many people in both NA & boosted applications, there is much positive feedback on other forums about the cams.
many guys even show timeslips or dyno sheets to verify the benefits.
now taking apart the front of my car is pretty easy = compared to reassembling everything in the correct order

["Q"]

I believe I'm currently running a pretty much entry level blower cam on a 383 stroker.
114 LSA on a Hydraulic Flat Tappet cam with 222*/226* @0.050 & a 0.464''/0.454''
Trying to keep it to about 5500rpm.

Planning to upgrade to a hydro-roller at some stage. Will be keeping an eye open for postings on that magic blower cam specs...

[suede57ford]

I recently finished my latest 312 Y-Block Ford with a larger cam. I was able to get a set of the new Mummert Aluminum Y-Block heads and had my intake professionally ported and flowed. My compression was 8.3 before, and is now 8.9. I went with an Isky cam with 254/260 at .050 duration with .560 lift. and 112 lobe center. The motor is a now a 352 c.i. stroker with a custom Moldex Crank and Weisco pistons. I currently run a blow-thru holley 750 with a factory '57 Ford VR57 supercharger with SN internals. It makes about 7lbs with the improved impeller. I only run pump 91 octane(best here at 3000ft altitude) with a bottle of 104 per tank. I have a BTM and knock about 2 degrees per lb of boost just ot be safe.

This new cam is about 10 degrees larger than what I ran before. It is way more radical sounding and it did soften the bottom end a bunch. It used to hit at 3000rpm, now it hits at 3500, and pulls up to 6000 hard. I find that I shift earlier as I get to the higher gears. I had to go to ET street tires(slicks) almost all the time now. I could not tune it with street tires, as it spins so bad in the first few gears from a roll that I couldn't get any load on the motor until I was going to fast on my test road.

My cam is a solid mushroom tappet cam, so my specs would be about 10 degrees higher than you would see with a hyd cam. I suppose I might go back down another another 10 degrees to about a 245 degree cam if I drove it more.

I'm getting it tuned in to do part of the Hot Rod Power Tour in it in a couple weeks. So It needs to get decent mileage.

I went down on primary jets and drilled the Power Valve Channels out to .075 to give it more fuel under boost, yet get my cruise fuel ratio up. I had to go to a 3.5 pv as the vacuum at idle with this cam was only 5-6in and the 6.5 pv was causing a rich condition at idle. I went up almost 10 sizes in the secondaries and that has helped get run richer under boost. I'm getting there. I'll be doing some dyno pulls once I get it dialed in a little closer.

[vinces427bb]

that sounds like alot of cam for that size engine.
you have modified the carb by yourself??
that always takes more tuning time, did you use a a/f-meter?
is this in a 57-fairlane or ?? i like that body style