Not a stroker question, but a head question. who better to a

[BREEZE1]

I am currently an running an all stock 4.0L renix engine. I do have a HO head out of a 91 model that I have ported and polished. I was thinking about getting the machine work done to install some 2.02 and 1.60 valves. Also I was thinking about running the 99+ intake manifold. My question is will this be good in producing any power, or will it have a dead spot when I hit the gas because there is sooo much flow available? I haven’t ported the compression chamber any, but I was wondering if I should have the head decked some maybe run the 0.043 head gasket to get a higher CR..?? Please help…..

[gradon]

Usually ported heads go hand in hand with better breathing cams. You'll definitely need to unshroud the intake valve if you do go 2.02"(you can lose performance just by going with a bigger valve). Decking the block and using a thinner HG will bump up compression and give you some more power, just be willing to use higher octane gas if necessary.

[SilverXJ]

I would deck the head for flatness, not to reduce the cc. As for larger valves I haven't seen anything that shows that they actually help on these engines. Even's Hescos Al head comes with standard size valves and they recommend against larger ones due to shrouding issues.

[Cheromaniac]

I am currently an running an all stock 4.0L renix engine. I do have a HO head out of a 91 model that I have ported and polished. I was thinking about getting the machine work done to install some 2.02 and 1.60 valves. Also I was thinking about running the 99+ intake manifold.

99+ intake manifold = Good idea
Larger valves = Don't bother. Keep the stock-sized valves.

[Flash]

Hay guys, Yeah i now been missing in action for a will..........

Been working on how to build, calibrate and us a flow bench, and won't be regular her for quit some time yet!

But when i do, I will display why larger valve is a no no with a 4L head.

I'm currently installing some 2.02 valve in my sb mopar. I have learn a lot and there's,.............. well, THE SKY'S THE LIMIT! In learning in this area.

I had no intention, of getting so deep into head porting, BUT, it has become an addition for me
There just NOT enough hours in a day, when I'm playing with this stuff

Later
Flash

[BREEZE1]

So say no to larger valves! Ok, well have a mildly ported an polished head with the intake and exhaust runners. Im planning on getting a 99+ intake manifold. I have a 91 HO throttle body that I have taken the taper off the bottom. I designed a 62mm throttle body plate and had it cut out on our laser. I designed it to sit at 8%, so that means its not perfectly circular, more of an oval shape but you cant see it with your eyes. I haven’t done the machine work do my throttle body to install it yet, but I was thinking why not machine a 1 inch throttle body spacer while im doing it? Ive heard that they don’t make much difference on a stroker, even sometimes hurt the hp. But ive seen where some folks claim to have a low 1 – 2hp gain with them on a stock 4.0L. So basically I have enough drop laying around our shop to make one, I just need to take the time to do it witch isn’t much. Theres no money being wasted there. I also plan on running the ford 5.0L injectors, I believe they are 19lbs. I cant remember right off hand. Any ways ill post some pics of my crappy head porting job. I view criticism as constructive criticism. Thanks bro’s!
before

after

[gradon]

You don't want to trumpet out the exhaust ports. You want a step going into the header. What I did with mine: If you look at your original pic, specifically the 7 o'clock position where there's a tiny bit of the carbon ring, I would keep that distance all the way around: