302 to 351W questions??

whippedsnk

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Nov 21, 2006
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Guys,

I am looking to start a project in building up a 351W. I have never built a shortblock so this will be a learning experience. I plan on taking my sweet time to get it right the 1st time out.

There is one close to me that is an 80s truck motor for cheap$.

My question is what is the better years if any to grab a 351W and stroke it out mildly?
I will be using a S-trim on it and want to make around 550-600whp?
I plan on using very good parts as I want to do this only once?

Thanks guys
 
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Guys,

I am looking to start a project in building up a 351W. I have never built a shortblock so this will be a learning experience. I plan on taking my sweet time to get it right the 1st time out.

There is one close to me that is an 80s truck motor for cheap$.

My question is what is the better years if any to grab a 351W and stroke it out mildly?
I will be using a S-trim on it and want to make around 550-600whp?
I plan on using very good parts as I want to do this only once?

Thanks guys

The 'best' year 351w will depend on what you consider more important
A) using factory 302 roller lifters and cam
B) getting the strongest 351w block possible.

Both can be worked around...
The 69 blocks are know as the top dogs of strength, but are pretty hard to find in good shape. The 70-74 blocks aren't as strong as the 69, but are stronger that the post 75 blocks.
Block strength didn't change significantly from 75 to the end of production.
Any production block should be able to handle 600-700hp pretty easily.

ALL 351w blocks before around 92 were non-roller blocks. A factory roller block can be easily identified by the 'F4TE' casting number. The real difference is the height of the lifter bores. Using a standard 302 cam grind in a non-roller 351w block will result in the oil hole in the lifter rising out of the lifter bore. This results in oil shooting directly out of the lifter, which is obviously bad for oil control.
You can use factory 302 rollers on a non-roller block, but a reduced base circle cam must be used. The reduced base circles are thought to have a negative impact on valvetrain geometry, so they should be avoided.
The final option is to use the 'link bar' 351w roller conversion lifters. These are expensive though...

Well, that is what I would consider when picking a block...



Do you have a car ready for this motor to go into?



I have a 351w swap writeup on my site, which has a lot of this info (and more).
jason
 
Thanks Jason/guys. Very helpful info!!

I do have a 89 GT that I picked up very recently, It has your typical mods plus an S-trim.

Havnt really even had a chance to drive it or look her over much to see how healthy it is.

It feels very stout though. Im getting back into foxes, after selling my 03 whippled COBRA. I had a stock 90 GT back in the day but now I can afford to play, so Im gonna... LOL. Foxes have always been my favorite.
 
I don't know 2 much about superchargers myself but remember that if you are going to build a 351 or a stroked 351w say to the tune of 408 cubic inch's you need to take that into consideration when you buy the s/c'er. You will need a bigger s/c'er tofill the added cubes of the 351w. btw i used a 72 block in my build. I didn't go with a roller cam but maybe in the future i will. So far the block and internals have stood up to 150 hp shot of nitrous for 6 years.
 
I have been told it is only the hyd rollers that cause issues.

I don't have direct experience though.

:shrug:


Well because I'm thinking, the problem with the oil hole is you're going to loose the oil out of the lifter, so they're not going to stay "pumped up"
solids don't need to be pumped up, I don't think they're as expensive as link bar lifters either. But is this oil thing really the only problem?

What i don't know is, can you use the spider/dogbone with lifters that are sitting up higher than normal?
 
Solid roller lifters are shorter because they don't contain a hydraulic plunger, so they should work just fine in a block designed for flat tappets with a standard base circle cam.

I'm not sure if solid roller lifters are a lot cheaper, but they will cost you more money overall. Roller lifters are much harder on the valvetrain, and will require heavier duty components like better springs, solid pushrods, premium rockers etc.. You also have to adjust the valvetrain periodically.

Solid roller cams are made for high RPM, they are generally a more agressive profile and utilize much stiffer springs. If the rest of the engine is not built for real abuse, you'll find the next weakest link
 
So I figure the answer is no, but I like to know the why's too.

Can you use solid roller lifters on the stock 5.0 cam? I know it's a hydraulic cam, so other than profile, what else is different between a hydraulic and solid roller cam?
Are the solid roller cams made of a harder material that allows it to withstand the stress of the solid setup?

If the metalurgy is the same, and being that hydraluic cams aren't as aggressive, I don't immediatly see any reason why you could use solid rollers on a hydraulic cam. But I might be missing something.

I could understand why you wouldn't use hydraluic lifters on a solid cam however.
 
I'm not sure if solid roller lifters are a lot cheaper, but they will cost you more money overall. Roller lifters are much harder on the valvetrain, and will require heavier duty components like better springs, solid pushrods, premium rockers etc.. You also have to adjust the valvetrain periodically.
I'm sure you meant to say solid lifters in the above quote. ;)
 
I meant solid roller lifters. If I had written just "solid" I would have meant solid flat tappet. Not trying to start a terminology debate, I just want to make it clear what I meant in my above posts.

If you go w/ a solid flat tappet, you wouldn't have the same durability issues I touched on in my previous posts. Lots of OEM engines in the sixties came w/ solid flat tappet cams and didn't have extreme-duty valve trains. For what it's worth, a solid flat tappet wouldn't be such a bad idea, they're lighter, rev really well (better than a hydraulic flat tappet or hydraulic roller), and would be a cheaper overall valvetrain. Plus, they sound cool.
The main concern w/ them is proper break-in.