So this whole poor man stroker thing......

[amceaglesx4]

I decided with my 4.7 stroker to go basically the poor man setup with the 258 crank , rods and oversized pistons. What I'm thinking is just using the stock 99 cam with a 43 head gasket. From what I read I should be somewhere in the 9.1 compressionratio are. So a few basic qquestions if anybody knows by chance. Also most likely the head and block will be planed just for straightness purposes. So...


What would my quench height be ?
Horsepower ballpark ? I'm thinking 250 +/-
Pistons I think will be the sealed power 677 60 over.

I figure with a basic build my AMC eagle sx4 is going to hall ass. Thanks and Merry Christmas to all

[nicpaige]

Quench will be determined by how much is taken off your deck plus the combination of rod length, piston compression height etc. You may guess close but the big factor is your deck height after machining.

[amceaglesx4]

My builder Joe recommended at least making sure everything is level and flat. I'm not going hog wild with the engine 250 will be more than enough lol. Stock is 114 lmao for a 1981 Amc Eagle

[Cheromaniac]

I decided with my 4.7 stroker to go basically the poor man setup with the 258 crank , rods and oversized pistons. What I'm thinking is just using the stock 99 cam with a 43 head gasket. From what I read I should be somewhere in the 9.1 compression ratio are. So a few basic questions if anybody knows by chance. Also most likely the head and block will be planed just for straightness purposes. So...

What would my quench height be ?
Horsepower ballpark ? I'm thinking 250 +/-
Pistons I think will be the sealed power 677 60 over.

I figure with a basic build my AMC eagle sx4 is going to hall ass. Thanks and Merry Christmas to all

I'd recommend that you go with the modified poor man's stroker build:

4.6L Modified "poor man's" stroker

Jeep 4.2L 3.895" stroke crank
Jeep 4.0L 6.125" rods
Custom forged +0.020" bore pistons, compression height 1.380", dish volume 26cc
9.25:1 CR
Stock 4.0 camshaft
DIY ported HO 1.91"/1.50" 57cc cylinder head
Mopar/Victor 0.043" head gasket
0.043" quench height
Accel 24lb/hr injectors for '96-'04 engines
245hp @ 4700rpm, 315lbft @ 3000rpm ('96-'04 camshaft)

The original poor man's stroker build that I have works great for me but isn't the best it could be. Quote from my site:

Original "poor man's" stroker

Same as above but with Jeep 4.2L 5.875" rods and Sealed Power 677CP +0.020" bore pistons. Unfortunately the high 0.088" quench height makes this combination more sensitive to detonation if the fuel quality is poor. This deficiency is rectified with the use of longer 4.0L connecting rods and custom forged pistons. This modified version is a great stroker build for a mild supercharger/turbo application with up to 6psi of boost. The 4.0L connecting rod/forged piston combination offers less reciprocating mass than the 4.2L rod/677P piston combination, thereby giving this engine a potentially higher rpm capability than the original "poor man's" stroker. The tight quench also allows this engine to run on 87 octane fuel in naturally-aspirated form.

[amceaglesx4]

If I stick with the 258 rods and the 677 pistons 60 over how can I bring the quench height down from .088 to the .043 ??? Can I take metal off the head and block ? If so how much ?

[jsawduste]

Your not listening very well. Why are you making things so hard and expensive ?

Use the 4.0 sized rods and a set of pistons from Russ, Bulltear or Diamond/Hesco. All the hard work has been done for you and you`ll end up with a good running reliable engine.

If your basing the use of the shorter 258 rods on dynamics then we can talk about dwell times, accel rates, rod angularity etc. However I strongly suspect this is not the case.

[Cheromaniac]

If I stick with the 258 rods and the 677 pistons 60 over how can I bring the quench height down from .088 to the .043 ???

Don't even bother.

Use the 4.0 sized rods and a set of pistons from Russ, Bulltear or Diamond/Hesco.

This.

[amceaglesx4]

See this is why I get angry. Poor man !!! I don't want to drop 4-500$ on custom pistons and change everything around. Its bad enough I can't buy a new crank for $200. Now its called a stroker crank for $400+. Every time I ask simple question I get re directed to more expensive shit. I found a thread where a guy built 3 short rod strokers with off the shelf shit all new for under $500. He bolted it up and went on his way. Simple !!! When mines is eventually done I'm going to post exactly what was done and with what so people like me know BOOM..... this is what I need and do to the engine.

[nicpaige]

I think what your hearing here is that your not that much more money going with 4.0 rods and forged "correct" compression height pistons than buying cast pistons and then paying to have your deck and maybe head cut down .040-.045"" to get your quench which costs money. Only you can determine how much you have to spend but machining isn't free, at least not for most. Good luck with your build whatever you decide. I think an AMC Eagle is a cool project!

[Cheromaniac]

See this is why I get angry. Poor man !!! I don't want to drop 4-500$ on custom pistons and change everything around. Its bad enough I can't buy a new crank for $200. Now its called a stroker crank for $400+.

Custom pistons at $450 will cost you less than the total cost of a set of 258 rods (unless you already have those for free), 677CP pistons, shaving the block deck, and buying a set of shorter pushrods ('cause you've shortened the deck height).
It's still a poor man's build 'cause the only extra costs you'll have over a stock 4.0 rebuild are the 258 crank, custom pistons, and oversize injectors. Unfortunately original 258 cranks have become scarce and the days of sub-$1000 stroker builds have long gone. If you're lucky, you might strike gold and find a complete 258 engine cheaply in the junkyards or on Craigslist to use for parts.

[Russ Pottenger]

I've been emailing Chris, and his engine builder Joe going over all of this information back channel with emails and one conversation with his engine builder.
Factoring in the cost the extra machine work of decking is block for quench versus buying a better piston (forged), longer 6.123 4.0 rod, and so on. Explain the potential cost of a finish 258 crank. $50.00 to $150.00 for initial cost of the crank and another $125.00 or so of machining and prep to get it ready for use.

If for budgetary reasons he insisted on going to the poor man's route, I explained to him and his machinist that I have a modified 2229 piston with 22, 24, and 26cc volumes that allows for a quench to be maintained, if he has his block decked approximately .050

He just has to decide he wants to shop at Walmart or Macy's



On a side note material cost going up, piston costs will go up next year about 5% or roughly $20 a set.

Russ

[amceaglesx4]

Doing a little more research and found out the 258 crank, rods and stock pistons ( 677 from Sealed power ) and that's basically it. Level the block and head looks like a 80 +/- quench height. With a 43 head gasket , little decking brings down quench height and compression is raised. I think I read 10 thousandths off equals .2 in compression. Don't quote me on that. I'm still not getting why .50 needs to be shaved off the block or custom dished pistons need to be used. I get there a lot of ways of making strokers but it seems like so much effort and peoples dollars are being wasted to custom make something that doesn't need to be fully custom. I found a talk site where someone simply took his friends strokers recipes and posted like 5 or 6 with exactly what was done. Simple. I'll try to get it here on the forum somehow. Even If I have to write it down and re-type it I will so it makes such a confusing website easy to understand It's worth it so people can read and say " fucking right !!! heres what I need "

[Cheromaniac]

Doing a little more research and found out the 258 crank, rods and stock pistons ( 677 from Sealed power ) and that's basically it. Level the block and head looks like a 80 +/- quench height. With a 43 head gasket , little decking brings down quench height and compression is raised. I think I read 10 thousandths off equals .2 in compression. Don't quote me on that.

Your math is correct.

I'm still not getting why .50 needs to be shaved off the block or custom dished pistons need to be used. I get there a lot of ways of making strokers but it seems like so much effort and peoples dollars are being wasted to custom make something that doesn't need to be fully custom.

You obviously didn't understand what I quoted in an earlier post so let me explain the reasoning to you again.
The original poor man's stroker and the modified poor man's stroker are equal in every respect except for the following:

Original poor man's stroker: 258 rods, 677 pistons, 0.088" quench
Modified poor man's stroker: 4.0 rods, custom pistons, 0.043" quench

The modified poor man's stroker will run on 87 octane fuel without detonation, while the original poor man's stroker needs a diet of 89 or 91 octane fuel. The tighter quench is the reason for the difference in fuel requirement.
The modified poor man's stroker costs maybe $100 more to build (assuming custom pistons $450, reconditioned 258 rods $200, 677AP pistons $150) but you'll soon recoup that at the gas pumps.

[jsawduste]

Suggest you forget this whole stroker thing and buy a crate engine from Summit Racing.
Then your only decision will be polished or painted valve covers. It might be a struggle to decide but you'll be OK.

[Cheromaniac]

Suggest you forget this whole stroker thing and buy a crate engine from Summit Racing.
Then your only decision will be polished or painted valve covers. It might be a struggle to decide but you'll be OK.