Cam suggestions

[Cuda]

Ok, today I brought home the block, crank, heads, and pistons today. We got the block on the stand and cleaned up the pistons.

I've decided to go back with the stock things that I can use. After getting the heads home and checking them very carefully, I think they will be ok. Had the crank turned .20 on the mains and .10 on the rods.

I'm going to go with the merc cast iron intake and q jet. The exhaust will be stock or slightly improved manifolds.

Staying with the stock pistons.

The original engine was a 1987 320 EFI.

I would like to make 320~340 horses at no more than 5200 rpm.

Any suggestion on cams?

Dennis Moore suggested the Comp Cams Xtreme Energy 256 H. It has 212/218 intake/exhaust duration, .447/.454 intake and exhaust lift and has a 110 degree Lobe Sep. Angle to me.

I was also looking at this Crane cam.
Cam Specifications


Degrees Duration @ .050 Int./Exh. Degrees Advertised Duration Int./Exh. Degree Lobe Separation Open/Close @.050" Cam Lift Int./Exh. Lash Hot Int./Exh. Gross Lift Int./Exh.
216
228 272
284 112 1 35
51 ( 3) .000
.000 .454
.480

Any other suggestions? Poodle?

[Forrest]

Cuda, that's the specs for the Crane H-272-2 Powermax camshaft (http://www.cranecams.com/master/apps/chevy13.htm#3.%20Hydraulic). Highly Recommended. Idles nicely with a little lope and has a nice smooth power band with a great top end. It is, however, right at the edge as far as your stock exhaust system is concerned. Don't use this cam with a through the drive exhaust.

[Cuda]

Thanks Forrest, now I'm debating on putting a set of Vortec heads on it. I just called to find out the price on a set of Vortec heads. I can get a pair completely rebuilt for $350, other than a different intake, is there any other issues I will run into by changing to Vortec? Will the same cam work with it?

[Rootsy]

with stock vortec heads... anything over 0.480 gross valve lift and you will either have to go to a longer stem valve, extra height retainer (and springs to maintain seat pressure) for increased assemblied height or you'll need to get the seats and guides cut down for retainer to guide clearance and to avoid coil bind with the stock spring....

if you go aftermarket camshaft and it requires dual springs you will most likely be required to cut the spring seats and guides so that the spring will fit and then install teflon seals on the guides... if you run a 1.25 OD single or 1.25 OD w/ damper you should be fine... as long as you keep it at or below 0.480 gross valve lift...

Rootsy - been there, got the tshirt...

[Cuda]

Rootsy, do you think that .480 max lift is on the conservative side or on the ragged edge?

[Rootsy]

honestly,

anything over .500 lift on stock pre-vortec and vortec heads is pretty much unbeneficial in our stuff... they just run out of breathing room... lift has less effect than duration, it is more about the area under the curve which in essence boils down to mean it is all about flow and velocity...

you'll see flat tappets with less lift than roller cams of the same durations... that essentially is due to the ramp profiles, the rollers being more aggressive.

vortec's are a definite step up from pre-vortec heads but come with other costs incurred... ie unique intake manifold, etc.

[Cuda]

So do you think the vortec heads will be ok with my .480 lift cam without having to modify the spring heights?

[Rick]

Cuda, Contact the cam people at Crane, or Competition or whoever you want. They will ask you some specific questions and give you enough information to help you select the best cam for your requirements. They have forgotten more about cam profiles and lap than most of us will ever know. Remember the ad "Lie to your friends, but don't lie to your cam grinder." Good luck Rick :cool:

[Cuda]

The Crane Tech Line was of no help whatsoever. They asked me what was the highest lift that was reccomended for the head. :( :confused:

[Rick]

Cuda, Sorry to hear about that. Competition were the people I got mine from and they were very helpful. Then again this has been a few years ago, and they ground some custom units for me. Rick

[BigGrizzly]

It all in whom you talk to. When I called comp cams about my clevlanf they told 10:1 was high and couldnt run that in a boat, I told tha=em that stock in the engine was 11:1 they told me I was wrong and they never put a Ford Clevland in a boat. I told them it was an H&M Donzi. He answered what is that? End of story. Some guys are good and some guys are $***-heads. any way I would go with Crane. Vortech heads are good but Rootsy is right. remembrt the more agressive the cam in the lift area the mor the valve gude wear is. Personalkly I use long duration cams witth close lobe centers. Forest has the 272 in his 16 with a 302 and I clocked hin with my GPS at 69 mph with two people in it and a bunch of gear. In case you don't it Forest isn't a little skinny guy neither was his pasinger either.

[turbo2256]

I direct most of my cam questions to Engle Cams. They have been in business longer than most owned by the same family. Only about 6 people work there. I f you call you talk to some one that grinds cams not a desk jocky that matches up your info on a computer spread sheet. They spend most of there time making cams for private companies such as Mondello. They do a lot of stuff for for the custom engine/boat builders.

[turbo2256]

Also a friend I used to work with that worked for Batten set up his own shop. Depending on the P/N on your heads you might be better off having the stock ones ported. I believe flow figures for the better castings he has up around 230 to 250 CFM @ between .450 and .500 lift depending on your cam. He keeps the port volume as low as possible to keep the air speed up. A few heads he has done I have put on cars retaining the stok cam and carb etc and have seen bigger power gains than than guys doing the regular bolt on stuff. We just pulled 700 some HP out of a 351C at around 7000 RPM not bad for the 4V heads.

[Ralph Savarese]

H-272-2
Great cam I am using it very satisfied
Total all around performance

[Cuda]

Ralph Savarese:
H-272-2
Great cam I am using it very satisfied
Total all around performance Ralph, what heads and intake did you use?

[smoothie]

turbo2256:
I direct most of my cam questions to Engle Cams. They have been in business longer than most owned by the same family. Only about 6 people work there. I f you call you talk to some one that grinds cams not a desk jocky that matches up your info on a computer spread sheet. They spend most of there time making cams for private companies such as Mondello. They do a lot of stuff for for the custom engine/boat builders. Yep! Thanks Turbo for this same recommendation two years back...

Click here (http://www.donzi.net/photos/100-0053_mvi.avi) to hear one run :)