Panteraguy

Hello all. I'm a newbie to this forum but thought this might be the best place to get some answers.
I just had my Pantera dynoed for the first time and being rather dissapointed by the results was hoping that some of the "gurus" here could lend some advice.
The engine is a 351c with 2v heads, TRW forged pistons creating 10.5 to 1 compression ratio. Heads are stock with porting to match the intake and exhaust. Bowls have been "cleaned up". Stainless valves w/5angle valve job and new valve inserts. Roller rocker conversion. Crane cam with .528 lift. MSD supplies the spark through a Blaster 2 coil and a MSD distributer, well, distributes the spark.
The dyno results show only about 270hp to the rear wheels. Does that seem low? I realize that I'm losing anywhere from 23% to 33% through the ZF transaxle but I was under the impression that this setup should produce over 400hp.
Any Ideas?

Thanks!

waxyourboard

I'd say with your mods, those numbers look fairly accurate. The Cleveland 2v heads don't quite flow well enough to get the numbers you're looking for... at .400 inches of lift, they flow a healthy 200 cfm on the intake. From there on up, it levels out or even goes down.

For a comparison, the ever-popular GT-40 heads flow about 203 cfm at .400 inches of lift on the intake, and up to 216 at .500 inches of lift.

http://www.mustangandfords.com/techa...288/index.html

If you want to make more power, you're probably going to either need the heads professionally ported, or get some new heads. The Cleveland 4v heads flow very decent out of the box, and with your pistons you would probably be able to run 89 octane or so with the american version.

Also, what exhaust are you running? Those 2v heads flow a buttload on the exhaust side of things

Panteraguy

Thanks Mark.
That makes me feel a little better. I actually have a set of the 4v heads but have been told that they aren't too great when it comes to low end torque.
The exhaust is unique to the Panteras and, from what I've been told, flows pretty well. It sure is loud!! Also forgot to mention that it's running a Demon 650 carb.

-Joel

anthonydalrymple

Out of curiousity; what was the rpm at the hp you stated? Was the power still climbing, but you shut it down early? It does seem rather low for a 400 horsepower motor. But, as already stated, not too far off for a 2V headed motor. There still is a small following of Cleveland fanatic's whom drag race. One friend of mine runs a 357C with modified 4V heads in a 3000lbs '69 fastback Mustang. Best et so far as been 10.80@122mph. The other buddy has a '79 Capri(looks like a '93GT mustang) with a stroker 408C. It ran 10.83@125 first time out two weeks ago....

Panteraguy

It looks as though the HP is dropping off at about 5800 rpm. Guess I'll have to start researching available heads. I've read a little about the Aussie 3v heads but didn't retain much.

-Thanks

anthonydalrymple

Edelbrock is making a Cleveland head in aluminum. I cannot say if it is a good head or not; but loosing 50lbs or more in weight, better heat dissapation, etc might make them worth looking at..... Power drop off point sounds right for the cam you have. I ran a Comp Cams 290S(solid) in my former 351CJ 4V. Came on like a freight train at 3,000rpm & pulled for "forever & a day". I shifted at 6,500rpm.... I ran that motor in a daily driven '70 Ranchero. It ran good; low 13's@105 on regular cheapo tires at the strip.....

Panteraguy

Thanks for the suggestion. I've found a link to CHI who makes the 3v heads. Here's the link. http://www.chiheads.com/3V_185CC.php

Tell me what you think.

NeoTokyo

The Ausi 3V heads are awesome heads but for how light your car is you really should go with the 4V Ausi heads, if you have off the line problems then put lower gears in. That engine you made needs to breath and those heads with a funnelweb intake and your demon will make it scream. There is no reason why you should not be able to get 500hp out of a well built 351C.

My wife was left a 71' Mach1 by her mother. It was the 330hp 11.5:1 CR option. That was a 351C 4V without any mods to it. Because it sat so long we are rebuilding the engine right now. Its going to be a 383 Stroker when we are done, The Mustang Depo on ebay has some awesome engine kits, but you have to talk to him to get the good stuff, he doesnt auction the kits usually with Forged 4340 lightened cranks, 4340 H-beams and ARP and whatnot, his prices are great, the best I have found and his stuff is name brand if you ask for it.

You should also think about a more radical cam with a longer duration, somewhere about 260-280 duration and a LSA of 114
Now choosing the right cam is very important, you should ask several shops that specialize with Clevelands, probably even a tech over there in Australia w/ the ausi 4V's.

Those Pantera heads should sell for a lot of money if you wish to sell them, that way you can buy the $1500 dollar bare Ausi aluminum heads. There was a guy in Oregon that was selling them on ebay for $1000 bux but he sold his last set or just gave up on ebay because I have not seen him for a year. He sells other Mach1 items though.

Good luck

-Eric-

Panteraguy

Thanks! From the info i've gotten so far it looks as though the 3v 218 heads might be the way to go. A rep for CHI seems to think that would probably be the best "all around" choice. As for changing the gears... that would probably cost twice as much as purchasing the heads. Remember, the Pantera runs a ZF transaxle and I doubt if my local tranny shop could slap in some new gears. I haven't made up my mind yet on the heads but I will take your advice and consult with some of the local engine builders before I commit to a decision.

anthonydalrymple

I checked out that CHI site & I really do like those heads.... Remind me of my AFR's on my Windsor. I like how they've reduced the intake port size down to a reasonable size for some velocity. I remember photo coping that Engine Master's Challenge article off the net some time ago; that Cleveland rocked & I was so impressed with it. I talked to my buddy whom builds Clevelands & races them(he built both of the cars I previously mentioned). He does not like the Edelbrocks; he feels they arn't hardly any better than regular American 2V cast iron heads. I didn't have time to have him ellaborate; I'm :ahem: working....