Stroker or Not

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BrianT said:
**** adds up fast.
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X2. I went with the stroker because my 340 crank had issues. (Plus, it was a 73 cast crank anyhow, so I wasn't giving up anything "strengthwise"). I've done other brand strokers and this lil Mopar beats 'em hands down. I was looking at doing a bore on the block, so the cost difference on pistons was negligable. Had a bad rod (the reason for the bore and unhappy crank) so in went a set of "I" beams. So there was the base for a lightweight big arm engine. Might as well balance it. You know, a solid lifter cam base on some circle track profiles would really bring out the torque band on this bad boy.......

Yep, it adds up.

Your budget is 4K for both an engine rebuild AND a trans refreshing with a better converter?
 
For someone on a tight budget it would be best to find a good 360 core because it has a longer stroke then a 340. Put some good flat top pistons in there to bring up compression, little bowl blending on heads and gasket match, small cam, and you can make an easy 400 hp and good torque. The longer stroke of a 360 is a significant advantage over a 340. Its the poor mans stroker engine. Bang for the buck you can't beat a good 360 build.
 
Sounds like he wants a driver with decent power 350-400hp i'd still go with the stroker with cast steel crank and hypereutectic pistons $700ish reuse your intake, carb, heads with valve job and pocket porting add a high lift 268 or 274ish cam your engine will be done by 5000 rpm so you don't need much of a stall.
 
AutoX

X heads. 2.02 1.60 Rebuilder is tops on porting. So for a few hundred more why not? That is provided the heads are OK. Are the exhaust valve seats hardened? If not we may have problems since I am fairly sure a lot of my leakdown is from valves. One cylinder likely has a broken ring cuz it dumps a bunch of air to crankcase.
 
Rev,

I may have to bump the budget I know. Doing some major landscaping as well so I may steal a bit from that. We will see. Right now I am comfortable dropping 15K between the two. So maybe that pondless water fall in the backyard will have to wait. LOL !!
 
spinman1949 said:
Rev,

I may have to bump the budget I know. Doing some major landscaping as well so I may steal a bit from that. We will see. Right now I am comfortable dropping 15K between the two. So maybe that pondless water fall in the backyard will have to wait. LOL !!
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If you buy the stroker kit, and build the engine with new parts the stroker route is only going to cost you an extra 550.00 if you compare the differences between resizing rods with arp bolts vs. new rods, hyperutectic pistons vs. the forged pistons in the stroker kit, and the new crank vs. regrinding a stock crank.
You will still need to balance the crank (wash). You still need bearings (wash)
So for 550.00 you get a forged piston, NEW 4340 lightweight I beam rod, and NEW 4" crank that is internally balanced. Money well spent IMO.

You could even put the stock heads on, and use a good hyd. cam and still get 400HP I'd bet.
 
spinman1949 said:
Rev,

I may have to bump the budget I know. Doing some major landscaping as well so I may steal a bit from that. We will see. Right now I am comfortable dropping 15K between the two. So maybe that pondless water fall in the backyard will have to wait. LOL !!
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Throw some styrofoam rocks in the corner and drape some Saranwrap down the center. You'll have a week before the wife catches on.......
 
I had the privilege and honor to visit with Brian T and his Dart. He really knows his stuff. He has one really bad ride. I took my 10 year old and that's all he wants now, a 67-69 Dart. After looking at Brian T's and a few on-line, I'd love to have one too. Once the vultures of life stop circling over-head, I'll have the money to get one.

Let me know when you get the stroker back. I can hardly wait.
 
ou812 said:
If you buy the stroker kit, and build the engine with new parts the stroker route is only going to cost you an extra 550.00 if you compare the differences between resizing rods with arp bolts vs. new rods, hyperutectic pistons vs. the forged pistons in the stroker kit, and the new crank vs. regrinding a stock crank.
You will still need to balance the crank (wash). You still need bearings (wash)
So for 550.00 you get a forged piston, NEW 4340 lightweight I beam rod, and NEW 4" crank that is internally balanced. Money well spent IMO.

You could even put the stock heads on, and use a good hyd. cam and still get 400HP I'd bet.
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Sorry, spinman1949 I thought it was more like $300 difference.

Maybe I was comparing forged pistons stock stroke to forged piston 4" stroke (IIRC, wash?)

OU812, do you think there is much to gain $$/HP in porting X heads on a 400 HP stroker motor?
 
I'm the anti stroker guy on here BUT if you are going to stay with 3.23 gears then I might well lean with the 4 inch stroke.

My 340 has 3.91 gears and 3,000 stall and it runs very strong on the street around here but the 3.91's are holding it back, really wants some 4.30 - 4.56 gears. You can gear for torque but not hp

Just keep in mind gas prices are going cheaper but higher. My 340 with 2.94's would get better mpg I would guess then a stroker with the same gears.
 
I have a Scat forged build 416 with ported heads, stock trans 2800 stall, and 3.23 rear. I am so pleased so far but need to build the trans soon and upgrade cooling a bit. I have receipts over 10K right so far but that is including all the other things you need when rebuilding and installing a new motor. I only started with a 340 block and a 318 in the car that didn't donate much so I am sure if you start with a running 340 you are going to do much better cost wise. The 416 and 3.23 gears is a great combination for the street.
 
autoxcuda said:
Sorry, spinman1949 I thought it was more like $300 difference.

Maybe I was comparing forged pistons stock stroke to forged piston 4" stroke (IIRC, wash?)

OU812, do you think there is much to gain $$/HP in porting X heads on a 400 HP stroker motor?
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Not IMO because they are prone to cracking, and you'll never get your money back out of them. If you spend 500-600 dollars in just porting alone, which is what it takes to really see a decent gain, you know you'll have way more in them with machine work, parts, etc....now how much will they resale for???? Pennies on the dollar.
 
my experiance with MPG and HP has been if you have more HP you don't have to mash the pedal as hard so if you go easy you may get better mileage if its not over carbed,which happens alot.A Turbo or super charger is the best example of this.But the more HP or torque you put in a car the more your foot wants to stay on the floor.
 
ou812 said:
Not IMO because they are prone to cracking, and you'll never get your money back out of them. If you spend 500-600 dollars in just porting alone, which is what it takes to really see a decent gain, you know you'll have way more in them with machine work, parts, etc....now how much will they resale for???? Pennies on the dollar.
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That's pretty noteworthy info comming from someone who has a flowbench and gets paid to port heads.
 
Auto,

" That's pretty noteworthy info coming from someone who has a flowbench and gets paid to port heads. "

Yes it is.

So I need to really look at a number of things. The good news is the guy that is going to do the work is first going to check out my work to confirm my findings. I just took it out today in 100 degree heat and it ran suprisingly well. Pulls to 6000 with no problem. And it is actually idling better. I am wondering if my adjusting the valves has allowed some to seat better. Of course that crankcase blow by on # 7 has me worried. Maybe broken ring, so the engine will still need to come out I am guessing.
 
mopar410 said:
Sorry,I only used the surface area volume on both charts so the calculator read it as the piston would travel down further and come back up with more air pressure to give it that much more compression.To get under 10:1 the piston would have to be in the hole some(don't want to guess an amount and be misleading).I did my test with 66 cc heads and those pistons were .018 out of the hole.
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Ha! The pistons don't just travel down further, they travel up further too - put those pistons on a 4-inch arm and they will NOT be .018 out of the hole.
 
Inspector71 said:
Listen to Brian T. He really knows his stuff.
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Thanks for the kind words Larry, but I'm no expert. Brian (OU812) is a professional engine builder with several magazine builds under his belt. He has probably forgotten more about strokers than I will ever know.
 
MoparAnglia said:
Ha! The pistons don't just travel down further, they travel up further too - put those pistons on a 4-inch arm and they will NOT be .018 out of the hole.
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Let me try to explain this better.The compression calculator only reads the top of the piston in relationship to the cyclinder ie:in the hole or out.So .018 out of the hole is the same regaurdless of the stroke.the compression is raised by the calculator by going from TDC to TDC as the piston will only be .018 out of the hole.You couldn't use the kb243 with a 4"stroke as it would be out of the hole probably past the top ring so a piston with the pin closer to the top of piston would have to be used but it could still end up at around .018 out of the hole if the right setup is used but that was 13:1 in my set up.Certainly not a pump gas combo.Most use the dish pistons to keep the CR under 10:1.


BTW I just built my 340 that was from the machine shop when I bought it so no machine work prices.Here is what I did.
$332.00 pistons KB243 .040
$305.00 Rods scat I beams rated at 650 hp
$165.00 cast crank not looking at over 400 hp stock stroke 3.31
$187.00 balance machine work on assemble and rod line bore
$989.00 FWIW gezz didnt realize I had that much in it lol.

Also my new setup each piston rod assy wieghed 233 gams=about half a pound less than the stock 318 setup as this crank is a 318 crank.you should see the holes they had to drill.
 
mopar410 said:
Let me try to explain this better.The compression calculator only reads the top of the piston in relationship to the cyclinder ie:in the hole or out.So .018 out of the hole is the same regaurdless of the stroke.the compression is raised by the calculator by going from TDC to TDC as the piston will only be .018 out of the hole.You couldn't use the kb243 with a 4"stroke as it would be out of the hole probably past the top ring so a piston with the pin closer to the top of piston would have to be used but it could still end up at around .018 out of the hole if the right setup is used but that was 13:1 in my set up.Certainly not a pump gas combo.Most use the dish pistons to keep the CR under 10:1.


BTW I just built my 340 that was from the machine shop when I bought it so no machine work prices.Here is what I did.
$332.00 pistons KB243 .040
$305.00 Rods scat I beams rated at 650 hp
$165.00 cast crank not looking at over 400 hp stock stroke 3.31
$187.00 balance machine work on assemble and rod line bore
$989.00 FWIW gezz didnt realize I had that much in it lol.

Also my new setup each piston rod assy wieghed 233 gams=about half a pound less than the stock 318 setup as this crank is a 318 crank.you should see the holes they had to drill.
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I get ya. I don't know anyone who's tried using slugs .018 out the hole on a pump gas stroker build though! Zero deck is pretty much spot on, flat tops on premium gas or dished on 89, depends on cam spec etc.
 
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