worked intake on a stock 4.0?

[VAhasnoWAVES]

i have a non running stroker that i plan to rebuild. it was/is a mildly built 4.6 that was aimed to run on 89 octane. the intake wasnt heavily worked, just lightly milled to support the greater air flow needed for the stroker to breath. i know im using relative terms here without a whole lot of accuracy... but as a general statement... will i see any benefit with bolting a ported/polished intake along with the 60mm throttle body to my stock 4.0 ('97).

the donor motor for the stroker was a '99.

 

[cruiser54]

Matching the intake and exhaust ports of the head and the manifolds to the gasket sure couldn't hurt. Did that on my HO into Renix project. You don't need to hog out the whole port in the head all the way to the valves.
A bigger throttle body like 60mm would increase the size up 2mm. I use 60mm throttle bodies, up from a stock 52mm, on my Renix motors with good results. I imagine a stroker woul love the bigger throttle body.

 

[wheeling365]

I agree with cruiser54 about matching the intake and exhaust ports to the head. I learned the term as gasket matching. Take an old gasket and lay it against the head. Mark and areas the there is material exposed thru the port openings. Then repeat the process on the intake/exhaust. That will give you an idea how far off the ports are from lining up. If you decide to grind on the head just don't get to carried away as there are oil/coolant passages in there you can break thru into.

As for porting out the head and intake runners cleaning them up a little bit can't hurt but I wouldn't try making them super smooth like glass. You do want some turbulance in the intake so the air can mix with the fuel spray from the injectors better.

I seem to recall reading poeple were opening up the stock TB's with not much effort at home because the had a "step" inside the bore that restricted flow. I'm just not sure what years that it applies to.

 

[VAhasnoWAVES]

from my understanding the stock throttle body can be bored strait through to 60mm, and the "step" as described is the only thing keeping it from being such. i suppose i may not have been clear enough, this question was about the intake manifold specifically... porting it should not HURT my motor, but im wondering if it will produce any gains in a stock 4.0.

 

[gradon]

Disco the battery, take your old intake off, buy a couple cans of carb cleaner and use an old tooth/nylon brush to clean the ports and valves on the head, use a little red rtv, install newer intake, reco battery. You might not gain much power or mpgs, but you aren't going to lose. I find it's easier to remove stock airbox and then you can use a couple extensions to get to the 14mm bolts. You might want to use a new gasket, so there's the two outside nuts and the middle bolt that are exclusive to the exhaust manifold. The good news is that you have a 97: 96-98s have the power-steering/tensioner setup that'll bolt right up to the 99+ intake; earlier years need modification/additional parts.

 

[cruiser54]

IIRC, the intake mani opening for the TB is already 60mm or bigger. It is on the Renix Jeeps even though they had a 52mm TB. I have had excellent results with bored TBs on 3 Renix Jeeps. I got them from www.strokedjeep.com. Of course, the difference is from 52mm to 60mm. I believe your stock TB is 58mm already. But, if I were doing things to a stroker, I'd be putting a bored TB on. BTW, I think Leigh Performance Machine does 62mm TBs for the later Jeeps and he has built a troker or two himself. Check out his adjustable MAP sensor mod for $25.