76-cj7
Oh yea.....im not too ed-ja-ma-cated when it comes to extreme engines so hat all would be required to do to the block or heads in order to accomplish taking my 304 to a 340? Oh yea, which heads do you all think would be a good bolt on for my 304?, like better flow and all that good stuff.
jeepsr4ever
No block mods and it would be a complete bolt in. No clearancing, nothing :?:
Goose
Ok Mc yer last post may have just saved the 304 in the CJ... hmmmm a 340 eh??? hmmm stroked and poked ya say ??? Hmmmm....
Dammit man.. I'm still trying to get all the jeeps lifted.. now, sheesh.. anybody got a refrigerator box I can live in when Linda throws me out?
You are a menace to marital bliss and tranquility..(Ok It's the Jeep habit but they don't laugh when ya accuse them of it).
76-cj7
I agree with GOOSE on this one. :sa: :!:
fifesjeep
a bolt in then.... then a bolt in it is...Sweet!!! I'm game!!!!
pablorg
What kind of gas do you have to run to avoid pinging if the compression goes to 10:1?
fifesjeep
I've got 10:1 FF Ross Race Pistons and 58cc heads... But my heads have been milled .003" and the block was shaved .005" and I'm running a little thinner head gaskets than stock... So, I'm figuring I'm running at-least 9.5:1 compression and I can toss in 93-95? What-ever premium is?
If somebody can figure the math and guess what or figure there-abouts what my compression ratios is that would be helpful? But anyway, I can run premium with no noticeable pinging... I also toss in a little 103 octane just for a little better burn... plus the exhaust smells a little better! 8)
The Ross Piston Company says that with the larger 58cc heads and running 10:1 pistons the compression ratio will be about 9.2:1.... Who knows for sure though...
tarior
$900 strikes me as DAMN cheap for a forged 4340 crank, let alone one for an AMC. Buy some, they'll sell.
Wrench Man
Personaly I don't understand why you would want to pay that kind of money to buld an engine that already exists?
Just go get a 343 or a 401, yea the stroker may make a little more torque but the shorter stoke will wind faster and make more HP. 111!!!
AMX69PHATTY
Would these cranks have a stroke of 3.75 inches ?
tarior
[quote=Wrench Man]Personaly I don't understand why you would want to pay that kind of money to buld an engine that already exists?
Just go get a 343 or a 401, yea the stroker may make a little more torque but the shorter stoke will wind faster and make more HP. 111!!![/quote]
Crankshafts have a finite service life, and are probably THE most unavailable AMC engine part.
fifesjeep
[quote=Wrench Man]Personaly I don't understand why you would want to pay that kind of money to buld an engine that already exists?
Just go get a 343 or a 401, yea the stroker may make a little more torque but the shorter stoke will wind faster and make more HP. 111!!![/quote]
Maybe where you are at 401's and 343's are plentiful... but here or most any other place these engines are like finding a needle in a hay stack... and chances are when you do find one she's been abused, bored, and she's cracked in various locations... If you can find 401's laying around like you can 360's then please let me know... I'll personally drive out there and buy 3 or 4 401's. :!:
Plus a 360 that's stroked and sitting between the frame rails of a Jeep would be total Nuts!!! :lo1l: I'm all for the lower nd grunt.... I already have a top end 360.. I guess it's time for a low end 360. :t:
jeepsr4ever
These would have a 3.68, 3.75, 3.9 and 4" stroke. The first step has been taken. A good core crank has been sent to the crank forging house. They claim a decent turn-around if they have tooling that is close. I have heard that nothing is very close for the AMC crankshaft but knowing what I do about forgings it is a very crude operation however I do not know much about the tooling involved (casting sand type, die cast...ect) I will post up more on this as we near a first article.
Thanks to those who have posted so far and please keep the votes coming. I do know many many of which are interested have not voted.
MaxW
I'm just about ready to rebuild my 360, and looking for the higher compression and a solid bottom end. $1400 is a big chunk of change, but sounds reasonable for a forged rotating stroker assembly.
John_TTD
I'm in, I've got a 360 that's dying to make some more power.
~John
76-cj7
Hey MC.....any news on these cranks yet?
JAVELINSST343
Hypothetically speaking, what would a 343 with this crank make? What rods could be used? I would like to make around 450 hp, is this a realistic goal on motor?
AMX69PHATTY
It states further back in the thread strokes of
3.68, 3.75, 3.900, & 4.000
note that an AMC 343 and 360 have the same bore 4.08
note that an AMC 290 and 304 have the same bore 3.75
note that an AMC 343 and 290 have the same stroke 3.28
note that an AMC 304 and 360 have the same stroke 3.44
Stock 343
4.08 x 3.28 = 343
343 .030 over
4.11 x 3.28 = 348
343 .030 over with 304/360 crank
4.11 x 3.44 = 365
343 .030 over with these cranks:
4.11 x 3.68 = 390 ( wow, what a coincidence ! )
4.11 x 3.75 = 398
4.11 x 3.90 = 414
4.11 x 4.00 = 424
note that the 3.68 stroke is same as stock AMC 401
so an AMC 343 or 360 block bored .030 over
and fitted with a stock 3.68 401 Crank is a 390
isn't that interesting .... :-| :-| :-|
Goose
Veddy Veddy Intelesting! indeed...
Are the journal sizes the same on all these cranks?
MaxW
So you are talking about 304 and 360 stroker cranks. How about the 390-401 engines? Is anyone out there thinking about a stroker crank for them?[/quote]
