351 Stroker questions
 

I have finally decided which direction to go on my pony. Instead of a blown small block combo, I am going with a stroker 392/393. 500hp and TKOII with 3.55s will make me happy. I plan, for now, on the FRPP 392 shortblock with AFR 185 heads. I'm still keeping coast highperf in mind though. I'm not settled on a cam yet (looking for suggestions and experiences).
My question is this:
I would like to use a truck lower with a downs upper and a 70mm TB will this hurt torque on a na combo? Or is the torque loss of a short runner intake acceptable due to the extra inherent torque of a 351W stroker. It will still be a while until I undertake the engine as I'm doing the platform items first (upgraded rear-end, suspention, brakes, roll cage etc).

I would think that you probably won't have too much trouble with it. You may lack a little bit of torque on the lowend (well, at least for the size of the engine) but that thing will absolutely scream when it hits the powerband. I don't think you should have any serious problems, plus that engine will have close to 400 horsepower and equal torque, so torque downlow will be a bit less but probably comparable to a stock 5.0L. I don't have any experience though, but thought i'd give my opinion since no one else posted :D

Why use a truck lower? There are so many superior manifolds avilable for a monster combo like that. I would look at the trick flow R intake or edelbrock victor for the 351.

Don't lose your time with a truck intake. Instead of buying the most expensive sreet head on the market, why don't you buy an edelbrock RPM kit or a Trick Flow kit. Both make good intake for a 351

Trick Flow

As far as I know they do not make nor have ever made a square port 351 truck lower..I know I have been looking at building a healthy N2O gulping 393 myself but I want to use my SysteMAX upper. If you find one let me know, the 351 lowers I have found are all round port GT40 style.

I have one question? Are you planning on building your own engine or having someone do it?

If you are planning on doing it yourself. Use a 400 crank. turn the mains down to fit the 351 block (not sure the dia.). Buy a good set ( I prefer Childs and Albert) of rods 6.25 inches long. Bore a block .030 over, and put good forged pistons (Ross, Kieth Black) or etc in it. You have a 408 stroker then. High revin motor that with a good set of heads and intake combo should have no problem making that 500 number. I would use the Trick Flow R heads. As far as intake goes, I stay away from efi cars so I can't suggest anything there.

Check out this combo...
http://www.alternativeauto.com/cars/lidio_lx.html

Thanks fellas for all the advice. I realize the trickflow for 351 is a good intake - I just hate the way it looks. As for edelbrock 351r, the short runner length would put put low end torque loss about there with the Downs combo. After looking at Lidio's combo - I'm decided, it just has such a clean look. I have seen the downs upper for the square port truck lower - http://www.thefordsource.com/store/m...induction.htm. Since the car will not see that much strip time, street manners are important too. The not too distant future will prob contain a procharger anyway. I just wanted to know how much lowend torque I will loose.

As for the Holley systemax upper it should fit a truck lower without too much trouble.

You can run a edelbrock 351 lower with a performer rpm upper if your worried about low end torque.

I do like the clean look of the downs box as compared to a large plenum sitting there.

tough call, perfromance would probably be similar, but if your looking for street manners, I would go with the edelbrock lower with the 5.0 performer rpm upper.

Does that mean you have seen square port 351 truck lowers? I have not been able to find one, I will buy one if you know where one is, all the ones around here are the round style like a GT-40.

rick i have a square 351 lower and a round 351 lower that i ported out to match my home made upper i have only found one at the wreckers but then i stopped looking it was from a late model f150.

Is there anyway to tell by looking at the intake if it is square or round? I will have to go hunting at a local srap yard I guess, I want a square lower so I can use my Holley upper on the 393/408 I plan to build, it will either be n2O guzzling or have boost.

Thanks A lot!