I have a 351m and im looking at 2 different intakes my buddys boss wants to sell. One is a Edelbrock "performer 400" and the other is a holley "Street dominator". Which one of these 2 would be the better one,he says the street dominator is the better of the two. Any opinions?

 

I heard that that cleveland engines really perform with single plane intakes.

 

try them both, run each one for a week. use silicone on the ends, and a light film of anti-seize on the gaskets so they dont stick and can be re-used. i'd be surprised if the description/application was very different for the two intakes, but you might find the difference if you were to run them both?

 

the science and experts say the dual plane is best for low-end and the single for higher rpm. Some testing that I've seen shows less difference but that could be due to other build changes etc. A 351m is not a low end motor (not much of a high end either). I have both and will test both on the dyno when I finish my propane/400 build. I would probably go with the edelbrock as it is a dual plane and I would erebuild my weak 351 to a 400 as soon as i could. The 400 is a low end torque monster and will easily give you 320+hp and 420ft/lbs with flattop pistons, inexpensive cam yada yada yada. Bust a lot more mud then.

 

Got to go with Roger on this. Dual planes are generally best unless you are racing. The single plane manifold will have alot less low-end torque, which pretty much does you no good when trying to pull away from a Chevy.

 

The answer kinda depends on the application. If its a heavy vehicle that you want some seat of the pants grunt then dual plane. If its a light vehicle that sees lots of high rpm action and or is built big enough to still have 'enough' low end torque despite the single plane, then I'd go with the single plane. I have used an edelbrock 400 manifold on my 351M and it defenatley helps the power band as compared to stock, along with a 4-barrel carb and some headers and free flowing exhaust.

 

the holley street dominator doesn't have monster big ports, comment for the 351Cleveland version was that the ports were on the small side, smaller than the ports in the head. the performer ports are also smaller than the ports in the head.

 

Tim Meyer dyno'ed a Holley Street Dominator, a Weiand 8010, and an Edelbrock Performer on his engine build. There wasn't a lot of difference between them. The Holley has the largest ports, but they were of no advantage with a midrange cam. Check his website:
www.tmeyerinc.com

http://www.tmeyerinc.com/400Fordpg4.htm

 

Everyone always says the dyno results are what to go by, that thier numbers dont lie. But the way I look at it is the dyno results usually only show a portion of the power. Most dyno graphs start at 3000 rpm or higher. And to tell you the truth my vehicle sees 3000 rpm maybe 1% of the time. I'd like to see the dyno number between 1500-3000 rpm where I do most of my driving. I bet there would be alot bigger difference between a single and dual cam. Not talking imparticular about Tim's results or these motors at all, but just in general. If memory serves, the stock 351m or 400 actually made peak torque at like 2,000 rpm didnt they?

 

With a small cam and a dual plane intake, peak torque will be at 2000 RPM. You would not want to run a single plane intake with this type cam, because the low RPM torque will be less, and you will not rev high enough for the single plane intake. If you look at the torque data for the Holley, it is definitly lower than for the dual plane intake. It also probably made peak torque at 3000 RPM or higher. Tim Meyer's testing was on a motor with an XE268 cam.

 

Something else I wanted to mention... ever since I read the car craft 400 build I always wanted to try the cam they use, which if I remember right is the XE268? Its specs however say its a 2500rpm and up cam. I thought this might not work so well in a big bronco. But I actually did exchange a few emails with a fellow I come across on the net who used this cam in a truck and he said it had awsome low end power, and that it was a "stump pullin mother effer". Depending on the rest of my design, I might try this cam when I build a motor.

 

I didn't find any Comp XE268H camshaft for a cleveland,351M or 400 engine.
Will Comp Cams release this cam for the 335 engine family?

 

XE 268H isn't listed as a production cam, talk to a tech and see what the deal is. it is listed for the 351W though, and i've read a few posts here and there that confirm that they can grind one for us. the dyno doesn't tell the whole story, especially how an intake is going to act on YOUR truck, with YOUR carb, cam, gears, tires, trans.... especially from idle to 2500 or less, in bumper to bumper traffic. that's where a lazy intake is going to exhibit bad manners, and that's where you don't want to put up with a bucking sputtering don't run for crap combo. that's why i suggested trying both of them, if it's possible? it's the best real world way to find the answer to your question, i think?

 

Make sure your CR is high enough, before using a cam as big as an XE268. Tim Meyer's motor and the Hot Rod magazine motor were near 10:1 CR.

It is hardly a 'low end power cam', but with enough compression it should be OK.

 

Flat-top pistons are not a cheap item they are only made custom for 600$ or more so I'd like to know where you shop at. Secondly the Edlebrock is better I run it on my 400 and blow the doors off of the chevy boys.