Picking up a 1971 351W engine this weekend to use for a 408 stroker build. I've currently got a 1982 F100 with a 302.

Working on engines is one thing that I know, but wasn't at all familiar with stroking. I've been doing a ton of research and I think I've got a better grasp on it.

So far what I've found out is there are numerous kits out there. I wanted to ask has anyone here done a 408? Looking for input on what crank, Rods, pistons, etc.

Would it be good to convert the engine from flat with a roller cam and linked roller lifters? It it necessary for a reliable engine?

A friend at work said at the most, stroking would only net a 20% increase in HP. I didn't ask if he meant at the crank or wheels. Is that true? He's trying to get me to turbo the engine...

Thanks for the help!

 

Cylinder heads and intake will ultimately limit how much HP the motor makes, stock heads for example won't make more than 260-275hp regardless how much displacement is under them so you absolutley need aftermarket heads to do a 408 justice. With those you could easily have an engine that makes 450+ hp and tq on pump gas.

A roller cam will free up some power and also eliminate the need for cam breakin and the requirement for a zinc additive in every oil change to prevent the flat tappet cam from self destructing. It's a pricey upgrade of course compared to what you can get a flat tappet cam and lifters for.

 

A '71 351 engine is not any better then a late model version of the 5.8L if you going to both stroke it and use a roller cam. The very late castings were cast with the taller lifter bores that would allow you to use OEM Ford roller lifters. What you save by not having to buy aftermarket link-bar hydraulic roller lifters you can put towards the purchase of the later block. And you do need better heads to make the investment in a stroker kit worth the cost. The best OEM heads are the GT40/GT40P heads and even ported I don't see you making more then low 300's HP wise. And forget about revving it past 5K, your peak power will be made in the 4K range no matter what cam you choose. It'll make a great towing engine though.

 

I appreciate the input, but I beg to differ.. A '71 block is much more stout and can handle engine stresses better before cracking. That is a known fact and the general consensus. I'm going with a '71 also because that is what I have available to purchase locally, but thankfully, they have 9.5" deck height.

I know GT40 heads are limited due to their chamber sizes. Would be fine if I wasn't stroking the engine, but would not work at all for a stroker. I never said in this post I was going with GT40 heads. I did mention it in another post on the bullnose section but realized afterward that they are limited for my application. I'm probably going with some Twisted Wedge 190 aluminum heads or something else. That's why I'm asking...

Sorry guys... I really do appreciate the input, and I don't know how else to say this, but I would rather have input from someone that has done this before. Just stating the obvious isn't going to help me at all. I'm wanting to hear from those that have stroked their engines to see what worked and what did not work. Not trying to be rude. Just really need to get good info in a short amount of time so I can start planning this build..