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A tale of two cams....paging the engine gurus

AJs72K5

AJs72K5

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Starting to plan out where to spend the holiday bonus that I haven't yet received. Based on feedback from you guys, the cam I currently have is too small. Mind you I haven't turned the thing over yet.

Here's a recap of the engine specs:

Block: GM 2 bolt BBC 454 .030 over Mark IV
Rotating assembly: GM cast crank, Speedpro flat top pistons (3cc eyebrows), retrofit hydraulic roller lifters
Heads: Edelbrock Performer High Compression aluminum cylinder heads...oval port, 100cc semi-open combustion chamber. Should be at about 10:1 compression
Intake: Edelbrock RPM air gap dual plane
Exhaust: Long tube headers with 2" primaries and 3.5" collectors (have these). Will run into dual 3" exhaust (need this)
EFI: Going to run FAST EZ EFI for sure, possibly the new 2.0

I've spoken with tech support guys at Comp and Lunati and have been given the following cam recommendations:

Comp: 11-422-8 -- advertised duration 270 In/276 Ex, lift 510 In/510 Ex, lobe sep 110*

Lunati: 20110711 -- advertised duration 272 In/280 Ex, lift 575 In/575 Ex, lobe sep 112*

Thoughts? burnout
 
I'm not very efi savy but I would think the FAST EFI folks need to be in on the cam conversation. There's a pretty fair difference between those 2 choices.
 
If your down to those 2 (I know there are about 1000 cams to choose from) but I would go big...BBC's like a lot of lift!
I have a CC 230/238..550/.570 solid in mine....and it isn't too much either. I have about 9:1 static and 781's w/ 2.19/1.88 and some port work done/RPM air gap and 1.625 I.D. headers...I run the FAST EZ 1st edition, and it gets on the rev limit pretty quickly for the Maidens' slim fighting weight of 6-6500lbs!
 
76zimmer said:
If your down to those 2 (I know there are about 1000 cams to choose from) but I would go big...BBC's like a lot of lift!
I have a CC 230/238..550/.570 solid in mine....and it isn't too much either. I have about 9:1 static and 781's w/ 2.19/1.88 and some port work done/RPM air gap and 1.625 I.D. headers...I run the FAST EZ 1st edition, and it gets on the rev limit pretty quickly for the Maidens' slim fighting weight of 6-6500lbs!
Click to expand...

Kinda what I was thinking Dave. My biggest concern on the Lunati was being too big for the cast bottom end. I tend to drive with a heavy foot.

Good to know a similar combo has worked well for you. How big of an exhaust you running out the back? I may have lots of questions for you when I start on the EFI.
 
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AJs72K5 said:
Kinda what I was thinking Dave. My biggest concern on the Lunati was being too big for the cast bottom end. I tend to drive with a heavy foot.

Good to know a similar combo has worked well for you. How big of an exhaust you running out the back? I may have lots of questions for you when I start on the EFI.
Click to expand...

Fire away!
I was looking at some Lunati's when my head guy recommended my present CC cam (mine is flat tappet) I put the numbers into my dyno 2000 program and it outperformed the Lunati Voodoo by 10-15 hp and tq.
My cast crank and studded 2 bolt bottom end hasn't been an issue so far...and I have my foot in it alot, my crank is .020/.020 balanced rotating assy. Pistons are SRP forged...030 over. I have 2.5" exhaust with flowmaster 40's...rev limit set at 5500 (and I have hit it quite a few times...it revs very quickly for a BBC I think) as recommended by my engine machinist.
 
Lift in the .500s is really nothing for a big block to gobble up.. 700 is beginning to get to be high lift depending on cubes.
 
I like that Lunati Voodoo cam. I've run two different Voodoo cams and I love them. They will give you pretty mild street manners but scream when you get into it. Both cams I ran with FAST EZ EFI and they provide plenty of vacuum at idle for a smooth enough idle.
 
Stomis said:
Lift in the .500s is really nothing for a big block to gobble up.. 700 is beginning to get to be high lift depending on cubes.
Click to expand...

I'm running an 1800-2000 stall converter on my 700r4. I think pushing it into the .600s would require me to change converters, which I don't really wanna do at this point.

Chevy305 said:
I like that Lunati Voodoo cam. I've run two different Voodoo cams and I love them. They will give you pretty mild street manners but scream when you get into it. Both cams I ran with FAST EZ EFI and they provide plenty of vacuum at idle for a smooth enough idle.
Click to expand...

Sweet. Good to know.
 
the voodo, fyi only silly old guys use advertised duration. I have a roller that is slightly bigger than that it has a noticeble idle but is making power right off idle.
 
the Luniti or mine? I have the mecury marine gen VI roller?

this is what is in mine. You used to be able to get them for $35 bucks or so.

Marine cam
This Mercruiser cam specs are:
GM#12551622
.050" 224*/224*
Lift .483"/. 483"
ICL 109*
ECL 122*
LSA 115.5*


The lift is smaller but duration and overlap are what kill your idle. Lift just kills valve train parts.
 
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