Question about my stroker motor...

[BlooDReigN]

Hey guys, sorry if this has been answered somewhere else but i did a good bit of searching and didn't come up with much.

Anyway, heres the deal. I have a DSS Pro Bullet 408W stroker kit and I have a line on a 69 351W block. Can anybody tell me if this stroker kit I have will work with both a 2 piece and 1 piece rear main seal? If it works with the 2 piece then I can go ahead and buy this 351W block and get finished up with my project....Thanks!

 

[vristang]

The only difference should be in the actual seal.

Congrats on the 69 block!
That is the dream of everyone who loves the 351w blocks.

jason

 

[Grn92LX]

I'm no expert nor do I claim to be but I would think the rotating assembly will work regardless you'll just need to buy the proper rear main seal for the block.

Good luck on your project $ounds fast

 

[BlooDReigN]

I'm just curious because some kits say they are just for 1 piece rear main seals and some say they are for both, but DSS doesn't specify on their site or anything.

 

[5.0Droptop]

Ask DSS they WILL know,.

 

[Rick 91GT]

Most aftermarket stroker cranks will work with both, best to double check since DSS uses various cranks suppliers. I've heard about the odd ball aftermarket crank made for 2 piece seal but I have never seen one.

The biggest issue is what deck height is the kit you have made for? If it is a 4" stroke, 6.2" rod, 1.300CH piston is it is made for a 9.5" deck height block 1971-present. The 69-70 blocks are 9.48"

Here's how you can tell

Take half the stroke + rod length + CH of the piston = DECK HEIGHT

 

[retro50]

The difference will be the oil slinger on the back of the crank. If it doesn't have one it will fit either block early and late. If it does have one it will only fit the early 2 piece seal blocks. I took a 289 crank and cut the slinger off and put it in a roller block and made a 289 roller motor I also used the 289 rods.

 

[BlooDReigN]

Is that deck height going to cause me any big problems rick? I'm pretty sure my rotating assembly is for a 9.5" deck height, but I'm not 100% sure.

 

[bluevenom867]

Is that deck height going to cause me any big problems rick? I'm pretty sure my rotating assembly is for a 9.5" deck height, but I'm not 100% sure.

The piston,MIGHT end up whackin' in to the head,or it might just give you a tigher quench and more compression.

 

[Rick 91GT]

if it is already 9.48 it means the piston will be .020" out of the bore which is too far, then if you have to deck the block to get it square and straight it will be even worse. They make kits for 9.48" heights...

 

[bluevenom867]

if it is already 9.48 it means the piston will be .020" out of the bore which is too far, then if you have to deck the block to get it square and straight it will be even worse. They make kits for 9.48" heights...

That kinda sucks...

But you can use a 9.48" kit in a 9.5" block,the piston would just be in the bore more.

 

[BlooDReigN]

Well the piston sits inside the bore a bit doesn't it? As long as the piston doesn't go any higher than the deck it should be fine, shouldn't it?

 

[bluevenom867]

Well the piston sits inside the bore a bit doesn't it? As long as the piston doesn't go any higher than the deck it should be fine, shouldn't it?

Well,generaly yes.

But in other instances you CAN have the piston come out of the bore a little,say a lower rpm steel roded motor with say a .040 compressed thickness head gaskets.

But lets say you are spining high rpms and got alum. rods,then you need it in the bore a bit as the rods will actualy "stretch".

 

[Rick 91GT]

If you have a kit made for 9.5" and your block is already at 9.48" it means the piston is out of the bore already .020" so it takes the quench with a .040" gasket to .020" which is too tight.

I haven't found a stock FORD block that has been straight so it will most likely need to be decked, which will push the piston out of the bore even more. This also make the top rin come closer to the deck which isn;t good for sealing on a power adder car.

I would have the block checked to see what the exact height is, have them check to make sure it is square and if it is not find out how much they are going to have to deck it. If the block is straight you could mill the tops of the pistons .020" depending on the brand, cap thickness, etc...

You really want the piston even with the deck of the block, this is called "0" and will yeild the best quench area (space between the piston and the head) for a STEEL ROD combo. With a Alum rod I would try to keep the pistons .012-.028 in the bore depending on the application.

 

[5.0 HOtrain]

I have a 69' blocked 418 stroker. I had the block before the rotating assembly however. I dont remember how much was taken off, but it did have to be decked. Witch meant..............$800 custom JE pistons . If I had already purchased a stroker kit, I would have checked into milling the pistons. I would call D.S.S. directly and find out what they would recomend, AFTER, getting the block checked. FWIW, I would do what is financially in you're range to make the block work. I also had the lower half of mine hardblocked with NO overheating issues. Good luck to you.
Mike.

 

[BlooDReigN]

Thanks for all the help guys