Vintage Mustang Forums banner

1 - 12 of 12 Posts

·
Registered
Joined
·
484 Posts
Discussion Starter #1
Hey guys, the motor is coming out hopefully next week, because I have to work all weekend. Anyways, I am planning on the parts to rebuild it. I am probably going to go with the KB 115 pistons with the 6.5cc valve reliefs. The heads are going to be AFR 165's 58 cc heads, with the 1.90 intake and 1.60 exhaust valves. The cam I am planning on using now is one of the Lunati Voodoo Cams. Here are the two that I am between.

Advertised Duration 262/ 268, Lift .499/ .522
or this one
Advertised Duration 256/ 262, Lift .483/ .499.

I'm not sure which one yet. If I have figured everything correctly, the KB115 with the heads I plan on using will give me about 9.28:1 comp. ratio. Will that be sufficient with either of the cams that I plan on using? Also, will I have any piston to valve clearance issues, I know that I will need to mock it up first with clay etc.

I plan to use a weiand stealth intake and an edelbrock 600 cfm carb to top it all off, long tube headers, 2.5 inch exahust with maganaflows, 3.50 rear gear, and a T-5 transmission. Please help me determine if this will be a good setup or not, and help me decide which cam would be the best. This will be a driver, but not a daily driver, but I would also like to be close to 300 rwhp. I would also like the engine to have a little bit of a lopey idle to it. Thanks guys, your the best!!!
 

·
Registered
Joined
·
153 Posts
I'm no expert, but I'd go with the bigger cam, with valves that big it's going to really want to breath and the bigger cam will help it do just that. Also you may want to step up to a little bigger carb, maybe a 650?

just my $.02
 

·
Registered
Joined
·
484 Posts
Discussion Starter #3
Well, now I have found a set of Edelbrock Performer 5.0 with the 1.90, 1.60 valves that have some mild port work done to the exhaust side and they have been milled to 58.5 combustion chamber size. Do you guys think that I would need to mill my intake to match considering they were 60 cc combustion chamber to start with. The only thing that is bad about these heads are that they are pedestal mount, but they do include roller rockers. The pedestal mount rockers should be fine with either cam shouldn't they?
 

·
Registered
Joined
·
3,848 Posts
IMO, the AFR 165 will make more power with the right engine/drive train combination.

FWIW, here are the test results from a MM&FF series on cylinder heads

http://a3.cpimg.com/image/3D/96/47811133-da15-020000F9-.jpg

Personally, I don't see a need for a dual pattern cam on the AFR heads....or most other aftermarket heads for that matter. The intake/exhaust ratios are such that the exhaust doesn't need to be crutched.

I'd look at the Comp 280H cam. I'd also want to run at least 10.0:1 static compression with aluminum heads.

Have a plan and have fun! :)
 

·
Registered
Joined
·
1,652 Posts
Id agree with mustngjoe about your compression. At least 10:1 with those aluminum heads. The stealth and 600 carb seem like the should be pretty good. As for the cam, im no expert, but to choose between those two I would probably go with the first one you listed, especially with the afr heads you plan to run. My piston-to-valve clearence was pretty tight on mine, but I had 66 289 heads with 1.94, 1.60s. I think 300rw might be attainable with that combo if you could get your compression up some. Here's a vid of what the idle sounds like on my car, the lift on the cam is .509 .512, and adv. duration 268/280. Video
 

·
Registered
Joined
·
256 Posts
Call Lunati, tell them what components you are using in the build and what you want the engine to do. They will spec the best cam for you. I've talked to them a couple of times, they were very helpful and explained why they recommended the cam and how it should perform.
 

·
Registered
Joined
·
3,805 Posts
I agree with the others as far as bumping up the static compression. The more cam you have, the more compression you need. Also, look at duration at .050 of lift when comparing cams. It is a better measure than advertised duration. Finally, overlap plays a big role. In addition to Lunati, call Comp Cams or Crane to get a second opinion.
 

·
Registered
Joined
·
3,047 Posts
Personally, I don't see a need for a dual pattern cam on the AFR heads....or most other aftermarket heads for that matter. The intake/exhaust ratios are such that the exhaust doesn't need to be crutched.
It might even be opposite with AFR.

Dyno fact: a friend did a 410hp 302 with AFR185 heads. The cam was, IIRC, B303, anyway single pattern cam. First pulls were done with 1.6 rockers and then 1.7 on intake and it did pick up power. However, when 1.7 was also tried on exhaust, there was neglible change in curves.
 

·
Registered
Joined
·
3,848 Posts
...It might even be opposite with AFR....
Well, I didn't want to "complicate" things with a cam spec that would look "different" to most (except you Arto ;))...but in fact the cam that was spec'd for my 331/AFR 185 combo had less exhaust lift than intake.

As I recall it was around .500 on the intake and .486 or so on the exhaust. A pretty mild cam by most standards. Still put 320+ to the wheels. :)
 

·
Registered
Joined
·
560 Posts
"cam dr." speced cam for my 185's was heavier on the intake side as well.
 

·
Registered
Joined
·
7,294 Posts
OK, I might as well chip in. Keep in mind, these are my own conclusions, so I wouldn't be surprised if they turned out to be BS.

With the typical split pattern cam and your typical SBF head, the most efficient port is the exhaust port, and the reason that split pattern cams are usually so effective is that they feed the more efficient port, while neglecting the worse port. So, it stands to reason if you have an extremely efficient head such as the AFR units, and the intake port is most efficent, feed it with a reverse split cam. Keep in mind though that heads like these are efficient in every way, so don't neglect the inefficent ports too much.

From what I've seen, a big, eg. .590/.560 lift cam is best, with a tight LSA and relativly little duration to keep torque up. The big lift numbers emphasize the intake, while pushing plenty of air through the exhaust as well.

For unported Edelbrocks and about 10:1 I'd get a hydraulic flat tappet with .560/.540 220/230 duration and 112LSA or something like that. 9:1 isn't enough compression for alum heads, you can run more on pump gas, do it and cam accordingly. ::
Just my $.02
--Kyle
 

·
Registered
Joined
·
6,911 Posts
If those cam specs are gross duration, those cams are tiny.


With either heads I'd also look at a single pattern cam.


I like Crane, or a custom grind laid out by a company like MME.
 
1 - 12 of 12 Posts
Top