No need to get out of control...

But it is a simple fact...it doesn't matter what your previous experience is. If you have not built a motor like this than you simply do not know from your experience. I could tell from what you've said that you havn't built this motor, so therefore I can conclude that you do not have the experience to say otherwise. The ONLY way you'd be able to say that you have the experience...is if you built a 393/408 under these circumstances and tested the difference, which I know you have not. So...again...therefore you cannot say you have the experience to say what you said.


You basically tried to tell us that you know simply because of your 4.6 experience. To me, that is not an experience that dictates what a 393/408 will do under these circumstances. Just because you built that 4.6 in that manner and had that result, does not mean you can translate that into you knowing what'll happen with a 393/408 in a "similar" circumstance of putting larger top end components on it.

I've built a 393 for myself...but I am not here saying I have the experience. I am using that experience along with the information from Jay Allen to make these statements...and Jay Allen does...and pleanty of it. He has more experience than all of us put together...hell he forgets more than I know.

I am not here to cause arguements or fustration to other people, but I try to get at the truth and help people not fall into false information...which is rediculously common on forums. There are a lot of "know it alls" out there who try to say this and that when they can't back it up or are saying what they heard.

I've heard it just like everyone else, the whole high velocity small port deal for low rpm torque....well....according to Jay this is a myth and I believe him because he has the experience to prove it.

 

Guys, This is great stuff! I say we prove it. I am putting a 393W in my truck now (1974 F100) I am having it done by a proffesional engine builder. He recomended a 750cfm Holley. He says this engine has to breath and anything less would be choking the engine. I am using factory heads from 1973. The engine builder said for my application of daily driver and money I am willing to spend this would be OK. He ported and polished the exhaust side and left the intake side to allow for better mixing of the air. I am using the performer style intake manifold. The cam he picked out is not what I expected, 214/224 He said it has better lobe separation. I should have the truck back next week and I will let you know how it runs. It cost $600 to dyno, I won't be dyno-ing! I will be running shorty headers and dual exhaust. Engine builder says the TQ will be more than the HP. He says I should have more TQ than most diesel. My goal is to have strong daily driver that gets good MPG and can blow the doors off if needed. A real sleeper! Does anyone have any suggestions for improvement?

 

if youre not revving past 6000 rpm youd be fine with a 600 cfm carb, and if you want better mileage and ease of street usage go edelbrock, also being a daily driver id use long tube headers vs shorties- better low end torque, just my .02

 

The shorties came with the 351w block and heads I bought for $150. I have looked throught the forums and no one has figured out the right long tube headers for the 1973 to 1979 F100/150 2wd with a 351W. Since these trucks did not come with this engine it is expensive to guess which ones work. Do you know of any that will work?

 

Didn't mean to start WWIII on this one.

 

We know warwagon, neither did I...

 

Well I'm not trying to start a fight, but that seems to be the notion I'm getting. I'm not a know-it-all by all means, didn't mean to come across that way, was just having a bad day is all. I'm about to build a 408 myself unless I find a killer deal on a good used diesel. If I build the 408, i'll take it to a chassis dyno and see what happens. I'm not gonna build this motor to be a all bottom end motor but one to run hi to mid 13's. Should be fun if a 4X4, I don't tow that much anyways. To clear things up I wasn't comparing a 4.6 to a 393. I was comparing a 4.6 to a 4.6.