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opinions needed for 351w build

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panteramatt

Member
I just aquired a 69 mach1 with a stock windsor. I want to eventually build a 500+ horse 408 but want to biuld this one now and stroke it a couple years later. I need opinions on a good top end that I can grow into that will be very streetable but make good power. I would like to get the car in the 11's na. I have a few q's:
1. I have a set of tw 170 heads. Would these be ok for a 408 or even a 351? If not, could they be ported to flow enough?

2. Whats a good easy to use carb and what size should I get?

3. Need a good intake suggestion

4. Would a cam that good for a 351 be good for a 408? Do 302 cams work in 351s? What off the shelf cam would be a good choice and work with power brakes?
 
TW heads are great. The 170s will be great with your 351, and yes they can be CNC'd when you go stroker. Everyone has a different opinion about carbs. I'm a Holley guy, but it's hard to argue that Edelbrocks/Carters aren't pretty darn bulletproof. 650-750 cfm for your 351 and 750-950 cfm for a 408 depending on the build. Intakes depend on build also, but good all around are Edelbrock Performer RPM or Weiand Stealth. Cam selection I would leave up to a pro like Camshaft Innovations for example. There is a lot to take into consideration. All small block Ford cams work, but there are two firing orders. 351s and late model 302s have one firing order, and early 260,289,302s have another.

I have the TW 205s and here are two places that can CNC yours:

http://www.foxlakeracing.com/twisted.php

http://www.totalengineairflow.com/products/fordhead/tfstw/

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Wow, so it would cost a lot to get them ported. Would a box set of afr 185's be better? I know they flow better and I could get them used a lot less than getting these ported.
 
AFR185s would be a good choice for either a 351 or 408, given that you want street manners. You could also use your TWs for both and have a very streetable torque monster with the 408. You'll sacrifice some HP with the smaller ports, but it sounds like you're not interested in a high RPM race motor anyway.
 
The firing order on the cam will depend on the cam itself. There's a great debate on which firing order is better -- 351 or 302. The late model 302 H.O. motors used the 351 firing order. IIRC, the standard 5.0 and the truck 5.0 used the original 302 firing order. Just find the cam that fits your engine and just use the firing order for that cam. I was running a Clay Smith Cam in my 351W, but it used the 302 firing order.

-rob
 
Honestly, I would stroke the motor now or wait till you have the money to stroke it; it will most likely save you money in the long run.

1) Twisted Wedge heads are a nice head but they will be maxed out even on a mild 351. They are not big enough to feed the extra cubic inches of a 408 and would have a hard time supporting 500hp even with a 408. In all reality the 170cc TW heads are a 302 head. You will need something with more port volumn for the 408. If you are looking for an in-between head I've got two good ones for you; Canfield 195's and Twisted Wedge fast-as-cast 190cc heads. They will work on a 351w and they would work on the 408 you are talking about building. They flow better than AFR 185 with a smaller port cross-section which means more flow and better port velocities. Porting heads is an expensive propostion; my advice is to buy a set of heads that will work for your build from the start. If you want to play a little bit with the 351w, just use the TW heads you have now with a mild flat tappet cam. It will be a fun motor till you build your stroker.

2) I like Barry Grant Demon carbs. Look at their Mighty Demon lineup of carbs. Choosing a carb is about the last thing you need to do on a build; choosing it up front without knowing how the rest of you build is going to shake out is just asking to have a mismatched carb. Look at the carbs with the annular boosters; the annular boosters get in a more stable flow at low rpms than downleg boosters, making more low torque, but they still make more hp up top. You will need two different carbs here; a 750 annular Mighty Demon for the 351w (or a 650 with downleg boosters) and a 850 annular for the 408w. If you want to play around get an inexpensive

3) For a 500+hp 408w I think that you are looking at a Edelbrock Vic Jr. intake. An Edelbrock RPM Air Gap would be another good choice. Either intake will work on a 351w build; in general the Air Gap will be a better street intake but the Vic Jr. can still make good down low torque given the right setup and it will beat the Air Gap up above 6000 rpms.

4) It is very unlikely that you will like the habits of your 351w with a cam in it that will make 500+hp in a 408...two different worlds here. You are looking at building two different motors here; a 351 with I'm assuming a stock bottom end and a 500+hp stroked sb with bb cubic inches. Stay away for 302 cams. There the same number of 351 cams out there as there are 302 cams, and personally, if you are seriously looking at going after 500+hp look into a custom cam when the time comes. Camshaft Innovations is a good one if you are looking for names. You are probably going to want to run a roller cam in the 408w to make that hp. Like I said, when the time comes ask and expert about a custom cam and what you need; they will know more than probably anyone on this board about exactly what you need. Get the right cam and you will have a well manored motor making all the hp it can make with your combo.

Like I said, I think that you should wait to spend your money until you are ready to build the stroker; two completely different motors.
 
Wow great writeup thanx a lot!!! Makes perfect sense and I think I will wait and work on other things like brakes first. It had manual 4 wheel drum and I will be converting to 4 wheel power disc so I guess I ll be needing advise on that when the time comes.
 
Get your drivetrain up to snuff as well to handle 500+hp before you build the motor. I wasted money and time building a 400hp 357w because my drivetrain wouldnt handle any more; now I'm trying to build a 500+hp 357w because I didn't stroke the motor in the first place because the drivetrain wouldnt handle the hp. It would have been cheaper to make the drivetrain mods first, then build the exact motor I wanted.

What transmission are you going to run? You will also need a 9" rear end(or 8.8" if you prefer a more modern rear end and dont mind making the modifications), and if you plan on running sticky tires for at the track, consider switching everything over to 1350 u-joints. Just get the drivetrain ready and your motor build will be more enjoyable :ecit
 
Well the car has a 9" and c4. Ill be driving it around all year starting in spring so if I feel I need a od, Ill be switching to a built aod, if not, Ill build the c4. Another topic all together, what can be done for suspenion to hook up? All the hp in the world aint worth a crap if it dont get to the ground!
 
A fairly cheap way to help traction and help control wheel hop is to install a set of traction bars. I've got Competition Engineering traction bars on my car; the non adjustable type. They go for around $150 and can handle 450hp at the wheels.

The next step up would be to go with an adjustable traction bar like a Cal-Trac. They are more expensive; $350 or so but are fully adjustable and if you are planning on getting into more serious racing they may be the ticket for you.

From there you have more complicated systems like a 3 or 4 link rear end; this is typically for strip only cars.

Obviously a good set of sticky tires is a must. Drag radials are great for getting good traction and the ability to drive you car on the street. I like Mickey Thompsons ET street drag radials, but there are other good ones out there made by BFGoodrich, M&H, and many others.

Depending on how much racing you plan on doing you may want to look into adjustable shocks. These can be adjusted to help perfect your hookup out of the holeshot.
 
I went with the Maier leaf springs that stack the leafs (leaves?) toward the front of the spring. This acts as a traction device without the need for anything additional. Maier part # MS2307

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I'll throw in my input on this. I just did my engine (blown 331 EFI) and used Jay Allen from Camshaftinnovations.com to design my heads, custom grind me a cam and the rest of the valvetrain. He did a great job. I ended up using TW Fast as Cast 190 heads. If you are serious about building your engine he would be a good place to get a ton of information before you buy. The cam I got from Jay wansn't much more than an OTS cam. He will take into account your desire for power brakes, tranny, rear end/gears, tires and a ton of other variables when he designs the cams.

I purchased my heads from him and he upgraded the valves and springs so that they would fit my combo and charged the same as an OTS head from Summit with inferior valves/springs. It would be well worth your time and money to have the engine planned out in advance.

http://www.camshaftinnovations.com/Camshafts.htm
 
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