notching a block for a 347

[347mustang1967]

i am making my 289 into a 347 stroker and i keep hearing i need to notch the block, i have no idea what that is or how to do it, i need some help, i need to know how to notch the block, what that means, what tools i need and how long it takes thanks

 

[96 DOHC Cobra]

It might depend on which block you're using, but I've always heard that the 347s didn't require any notching.

 

[347mustang1967]

id be rele happy if it didnt require it my block is at the shop gettin bored out so i cant tell rite now (they arn't notching it cuz its to expensive) but as i said i keep hearin a 347 needs notching its a late 1966 289 block

 

[mustbereel]

You will need to notch the bottoms of each cylinder wall to avoid rod interference.

See this link.

-Stroker Tool

 

[woodsnake]

Also, my understanding is that a 'early' 289 block is not a good candidate for a stroker due to the two piece rear mail seal, and that they are prone to leak. While it is at the shop, find out about machining a one piece rear main seal.

 

[347mustang1967]

i really pray thats not true i mean the block is mint

 

[Rusty67]

Not sure about the notching thing but while you have it there, have them drill and tap the head bolt holes out to 351w size and use a set of 351w head studs. This will keep you from lifting a head gasket later.

 

[jb1dsl]

needs notching, cost me 50 dollars to get mine notched by the machine shop

 

[Buckhunter125@h]

I'm doing the same thing for my 68 FB . I finally gave up on getting advice on the internet and talked to a real live high performance engine builder ....................... he tells me the 289 block is the BEST block ( of the stock blocks) for a stroker project . He says it is the strongest block out there .................. yes it does need notching ( so does a 302 block )

You can also have it machined to accept stock style roller lifters instead of the retro bar link rollers if you are planning a roller cam . ...... good luck

 

[Nosboss]

Yes, it needs notched. I am in the process of building my 347 motor right now. I can snap a couple of pics for you later if you would like...

 

[347mustang1967]

lol good i was beginning to worry if the 289 was a good block and mines in perfect condition I'm sticking with good ol' hydraulic flat tappet and a brand new comp cam, those guys over at the darn machine shop told me they would notch the block for 2000 which i thought was ridiculous

 

[Rusty67]

Do the 5.0s need to be notched as well ? They have a taller deck height from what I understand.

 

[stonecoldtx]

Do the 5.0s need to be notched as well ? They have a taller deck height from what I understand.

There is no difference in deck height between a 289, an early model 302 or a late model 5.0.

There is a difference in deck height between these engines and a 351, both Cleveland and Windsor.

There are deck height differences between a Cleveland and a Windsor

There are even deck height differences between different years of Windsor blocks, with the early ones at 9.48" and the later ones at 9.503", but there are no differences at all in the deck heights of the 289/302/5.0L

There are differences in the length of the cylinders between a 289 and a 302--I can't remember which is which, but one of them has longer cylinders (I think it's the 302, mainly because it's got a longer stroke, but just can't remember).

The earlier blocks were thicker, with the Mexican blocks and the 289 HiPo blocks rumored to have the most "meat" in them

In (I believe) 1979, the 302 blocks became thinner, and were re-designated "5.0L"; they started using hollow crankshafts that required a heavier 50-oz imbalance instead of the previously used 28-oz imbalance.

I believe in 1983 or 1984, they started using roller hydraulic camshafts, which required the lifter bores to be longer or taller, depending on how you want to look at it.

I'm not sure when they started using one-piece rear main seals, but I think it might have been around that time as well.

 

[blown65]

Do the 5.0s need to be notched as well ? They have a taller deck height from what I understand.

Yes, I did a 347 with a brand new 5.0 block and it required notching. Same with my R302 block. Its really not that big of a deal though.

 

[woodsnake]

I will need to see some evidence that a 289 block does not need a one piece rear main conversion, to make a better stroker candidate.....

While it may be a "stronger" block than a ~74~ on up, it is still prone to leaking....

I offered my bit of information more from reading HP books, rather than 'internet only' research.

I don't want to sound bitchy about it, but I would like to see something else cited.....

 

[Rusty67]

The 2 piece rear main seal is just easier to replace. If the cost of machining the crank is too high then keep it as a 2 piece.

 

[Nosboss]

Here is a couple of pics of the notching needed for a standard 3.4" 347 stroker crank. This is on a '90 roller motor that I am in the process of making a 347 out of.

 

[NasaGT]

Nice pics!

When you do this, how much clearance is required between the block and all moving parts?