Stroker?

[vin1382]

I know that stroking a motor will increase its displacement..but thats pretty much where my knowledge ends. What exactly do you replace and change when you stroke a motor? How do you know what displacement it will make when you are done?

Would it be safer to supercharge my 351w without stroking it? Or could i stroke it up a bit and then supercharge it without worrrying if my engine life is going to shorten?

 

[usedtobe 67p51d]

yes you can stroke it, it's done by changing the crank,rods,& pistons. as for life, yep you'll shorten it the more h.p. the shorter the life of the motor,

 

[rbohm]

depending on how much power you want out of the motor, stroking or supercharging could be your best bet. you can combine both if you choose. it also depends on what type of power you want, meaning high rpm power or low rpm power. stroking is an easy way to get low and midrange power, and, except for a roots type blower, supercharging, or turbocharging is a good way to get mid range and high rpm power. as was stated, anytime you increase power, you decrease the life of the engine. how much depends on how much maintenance you give the engine, and how you use the engine.

 

[vin1382]

depending on how much power you want out of the motor, stroking or supercharging could be your best bet. you can combine both if you choose. it also depends on what type of power you want, meaning high rpm power or low rpm power. stroking is an easy way to get low and midrange power, and, except for a roots type blower, supercharging, or turbocharging is a good way to get mid range and high rpm power. as was stated, anytime you increase power, you decrease the life of the engine. how much depends on how much maintenance you give the engine, and how you use the engine.

I think I would rather have low-midrange power. maybe up to 6000 rpms or a little more. What sizes can you stroke a 351w to?

 

[SadbutTrue]

I think I would rather have low-midrange power. maybe up to 6000 rpms or a little more. What sizes can you stroke a 351w to?

393 and 408 are the most popular, but i've also heard of 377, 383, 392, the almighty 427 and others

 

[vin1382]

393 and 408 are the most popular, but i've also heard of 377, 383, 392, the almighty 427 and others

Not bad. I've heard of lots of people doing 393's. Any idea how much a kit would cost to get it up to 393? What companies make them? Lets say I have a fairly stock windor, and i up it to a 393. Without changin the heads or the cam, what will i be looking at as far as increases in hp and tq? (im definalty doing heads and cam...but i want to know what do to first..heads and cam..or stroker and then heads and cam?)

Thanks so far for info!

 

[mp67]

Not bad. I've heard of lots of people doing 393's. Any idea how much a kit would cost to get it up to 393? What companies make them? Lets say I have a fairly stock windor, and i up it to a 393. Without changin the heads or the cam, what will i be looking at as far as increases in hp and tq? (im definalty doing heads and cam...but i want to know what do to first..heads and cam..or stroker and then heads and cam?)

Thanks so far for info!

Cost of a decent crank, rods and pistons stroker kit will run you 1500 or so. some cost less, but offer inferior parts. If your not shooting over 400hp, you can get away with cast parts, but if you want to supercharge, you better get all forged. www.coasthigh.com, dndmotorsports.com, among others offer everything from stroker kits to shortblocks, to longblocks, to complete engines. If you add up the cost of the stroker kit, block prep, parts, heads, balancing and blueprinting, I found it cheaper to go with a longbock. Stay away from speedomotive. Lots of people on this board have given them bad reviews.

Oh, and if you decide not to go with a short or longblock, do the stroker first. You need to build the bottom end first. If you waste time and money doing heads and cam, you just have to take all that apart to stroke the motor.

 

[mp67]

as for life, yep you'll shorten it the more h.p. the shorter the life of the motor,

This is incorrect. Just adding hp does not shorten the life. Its adding to much hp and using it on a regular basis without using quality parts. Example:1996 GT with 4.6 engine making 225hp. 2005 gt making 300hp. Is the 2005 motor going to have a shorter life than the 96 cause ford has increased hp by 75? No, cause they use the appropriate part. If you stroke a motor and used cast pistons, that is fine for a certain level of hp. If you go beyond that, you need forged pistons. Same with rods, crank, main and rod bolts etc..

Now, if you are going to flog this motor on a regular basis then that is what will shorten lifespan.

 

[vin1382]

Cost of a decent crank, rods and pistons stroker kit will run you 1500 or so. some cost less, but offer inferior parts. If your not shooting over 400hp, you can get away with cast parts, but if you want to supercharge, you better get all forged. www.coasthigh.com, dndmotorsports.com, among others offer everything from stroker kits to shortblocks, to longblocks, to complete engines. If you add up the cost of the stroker kit, block prep, parts, heads, balancing and blueprinting, I found it cheaper to go with a longbock. Stay away from speedomotive. Lots of people on this board have given them bad reviews.

Oh, and if you decide not to go with a short or longblock, do the stroker first. You need to build the bottom end first. If you waste time and money doing heads and cam, you just have to take all that apart to stroke the motor.

Stupid question...what is a long block or a short block? i see them being advertised all the time in magazines. what advantage does one have over the other?

 

[LMan]

short block is block, crank, rods, pistons...basically the reciprocating assembly.

Longblock is the above plus cam, heads, and valvetrain.