Stroker motor ???s

Stroker motor ???s
B

battleship

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pennsylvania
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s10 4 door 4wd ,cj5 parts jeep
I have been porring over jeep sites in my free time and came upon the stroker idea gone using a 4.0 head on a AMC 258 i6 / 4.2l , have any of you cone this route? What are the pros and cons that you dealt with? From what I have read a .060 overbore would bump a AMC 258 i6 / 4.2l to 4.6 or 4.7 l from AMC 258 i6 / 4.2l . Would like to stay carbed not FI and a carb in the 390 to 460 cfm range would be called for. Harder than running a turbo? or 6 of one half dozen of the other? I know tourque would be greater but overall performance as a mainly street driver w/ a good bit being highway w some light towing. Looking for Ideas. Money is not a big part of the prob but would like to get the most bang for the least dinero. Ooops my bad should have put this in Drivetrain Mods If u would, many thanks.
 
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Is your engine ready for a rebuild anyway? If not you might want to sell your 6 and get a V8. There's no replacement for cubic inches. The engine will be more reliable and powerful.
Otherwise you have some good ideas. The head swap and boring will help a bit but it won't be a stroker motor. To build a stroker motor you need a new crank shaft that has a longer stroke. That will push the pistons higher up into the engine and down lower. To keep the pistons from smashing into the cylinder head you will also need to replace the pistons with lower profile ones. The connecting rods will also be replaced. With all these moving parts replaced your engine will get a longer stroke.
 
BrockGrimes said:
I've seen dyno sheets.
Click to expand...

Brock, I'm A believer....but knowbody just changes the head do they? If you do the 4.0 head you have to use a 4.0 exhaust manifold and that is in most cases" header like" compared to the AMC 258 i6 / 4.2l cast iron boat anchor and that has to contribute to the increase in HP?
 
To swap the 4.0 head somethigns need to be changed, but a stock swap with not porting polishing, etc. has made 40+ on a good motor.
 
Here is a quote from Leee at Hesco from a conversation we had..

"My aluminum head is legal for a 78 year, that with MPI kit will add almost 100HP to a 78 Jeep."

Now I wasn't ready to shell out $2K for that head but was a little tempted;)
 
Sasquach said:
Here is a quote from Leee at Hesco from a conversation we had..

"My aluminum head is legal for a 78 year, that with MPI kit will add almost 100HP to a 78 Jeep."
Click to expand...
Add 100 horses to a 115 HP engine ! ! !
That's quite a claim.
BTW Hesco also makes stroker kits for the 4.0 but I don't know if they have one for the AMC 258 i6 / 4.2l


Engine Specs - Jeep Engines
 
If you are really set on stroking a six you are looking at.the.wrong engine. I know you said you want to stay carbed but especially with a modified engine like that you will really appreciate the reliabilty of risk injection. If you got your hands on a decent 4.0 you can build a poor man's stroker where you esentially take the crank and rods from your AMC 258 i6 / 4.2l and install them in the 4.0. If I remember correctly that yeilds 4.6 without boring the cylinders on the 4.0. From there you can bore it out and change the piston dishes etc etc and get larger displacement.

quadratec sells a long block 4.6 stroker made by a company called golen for like 3500 bucks. I personally would just buy that one before trying to peice together one because I don't have a shop and figure that by the time that I paid a machine shop to do all the work I'd be fairly close to the cost of the golen.
 
Thisguy thanks for yours and everybodys inputs just from your answers I have a better idea of the things I should consider on this project friends have sggested an 8 but I want something unique the other day driving my s10 swapping in a 4.3 crossed my mind. But still the AMC 258 i6 / 4.2l would be my first choice.
 
You can jump aboard the train with me and Sasquach and do the 4.0 head and MPFI upgrade and see how you like it
 
I'm running a hesco 287 (4.7 litre) stroker in my XJ and LOVE IT! It dyno'ed out at 225 HP at 3800 RPM, and 305 ft lbs torque at 2500 RPM. Not to mention it gets 20-25 MPG....with 31"s and 3.55 gears. I haven't personaly seen stroker kits for AMC 258 i6 / 4.2l 's, but I'm sure they're out there.
 
thisguyyouknow is right you don't stroke a AMC 258 i6 / 4.2l you use a 4.0 block and head with a AMC 258 i6 / 4.2l crank, and rods. the bores are pretty close between the AMC 258 i6 / 4.2l and 4.0, its the stroke that changes the cubic in. the blocks are almost the same, the heads are different as well as the intake and exhaust manifolds. if you just want to do a 4.0 head swap and keep your factory intake you can, but you will have to have a 4.0 exhaust manifold.
seems like this site here might have all of the info on building a stroker motor than you'll ever need Jeep Strokers • Homepage
 
Cheepjeep85 said:
thisguyyouknowhttp://www.jeepstrokers.com/forum/index.php?sid=8774ef23b878600b5fc75424697c6b53
Click to expand...
its THISGUYUKNOW!!!! Get it right or pay the price!!!!:biggun:This is the internet we don't spell things properly lol I've been using this screen name since my dad got dial up AOL in middle school HaHa :D

XJ287 I would like to know your cost on that stroker set up. I would also like to know if you were able to get it to run off regular gas. Also did you buy the kit and the kit from hesco and then stroke a regular 4.0 or did you buy an already stroked 4.7 from hesco. The golen 4.6(or is it 4.7?) stroker http://www.quadratec.com/products/51107_50X_PG.htm is 3500 and you still need to find a timing cover, serp accessories, FI components, ETC. All which can be done fairly cheaply if you go junkyard diving but I would like to know your final bottom line everything done cost. THinking if the 360 ever take a dump on me I will replace it with a stroker depending on how much the cost compares to rebuilding the 360.
 
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