budget 4.5 stroker will it run pump gas?

[daccarettfletez]

Hi,
I'm planning on building a stroker (on the tightest budget possible!) on my 1993 4.0 HO, that is in very good shape, so I want to ask for your opinion regarding DCR and pinging on pump gas, here is the setup:

block: 1993_ 4.0
Crankshaft and rods: 1981_ 258
Camshaft: Stock 4.0
pistons: Stock 4.0 no overbore
head gasket: ? Victor Reinz I guess?
injectors: Ford blue 24 lb
No decking or shaving.

Could you ballpark my DCR and advice me if it will ping?

[Mgardiner1]

http://www.jeepstrokers.com/calculator for your DCR.

Large quench isn't good for pinging, but about .030 deck clearance and stock cam, even with the longer stroke, shouldn't give you much problems on pump gas.

[Cheromaniac]

Sounds like you're trying to copy my "poor man's" stroker but without the overbore. Mine runs great and doesn't ping on 91 octane in mid-summer heat even though I'm using the hotter stock Champion RC12LYC plugs. Static CR is 9.25:1 and dynamic CR is 7.36:1.

[oletshot]

You can dish the stock pistons to lower your CR. I dished mine to 23cc.That way you can use the Victor .043" head gasket without worrying about raising your CR.

The "poor man's" 4.5L stroker makes an interesting combination. With the .043" HG and the stock pistons, quench ends up identical to stock 4.0. I put a Clevite cam in mine (.448" lift). I choose to dish my pistons more to try to get the DCR close to stock 4.0L and run on 87 octane, as my son will be buying the gas and I didn't want to stick him with the extra cost of premium. I still have to assemble the valve train. We are starting to get all the parts together for the 2.5 to 4.5 swap in his YJ. Anyone got a 91-95 YJ 4.0L engine harness they would like to sell?