ported and polished intakes?

[Purdue72]

I'm having trouble finding someone here in Georgia that will port and polish my intake, they all refer me to California. I really don't want to go to that extreme. Has anyone had theirs done, and did it make a great improvement or not?

 

[410Fortune]

the OHV 4.0L actually has pretty well flowing intake manifolds

However it can use some serious gasket matcing where the upper meets the lower and the lower meets the intake.

Your best bet is to do them yourself with a dremmel.
Maybe get a spare set from a junk yard or on the boards and work on them.

If you want to port and polish the intakes you can refer to Svenn Pruette's book, "How to build and modify Ford 60 degree V6 engines". Sven (Vanir tech.) has illustrations and everything you need to know about what the aluminum OHV intake manifolds need/dont need.

Now since the stock pieces actually flow quite well, have you already done all the other intake and exhaust modifications to the engine, becase with airflow you are only as good as your smallest bottleneck.

More HP gains will be found in having the heads ported and polished and also by getting an aftermarket cam then you will ever see with ported intakes on the OHV 4.0L.......

 

[BeauJ]

I agree with 410, id just use a dremel and port it myself, but gasket matching will have you pulling your hair out. You wont see that big of a HP gain and their really no need unless you plan on putting a hefty shot of nitrous or a supercharger. Theres a guy 5 mins. down the road from me, about an hour away from dallas, that all he works on is 5.0 engines, thats his specialty, and he ports intakes but i dont know if hed do a 4.0

 

[SteveVB]

If you have the engine apart then yes go ahead and do it. I wouldnt take the manifold off to do any work to it. Like 410 said the intakes flow decently until you get pretty wild cams. So for a stock or close to stock build it wont make muck difference.
My engine had a big mismatchs between the upper intake, the fuel rail and the lower intake- I gasket matched them all. I doubt it added any power, maybe a bit at the margin, but made me feel better that the air had a better shot at the head.

If you want to do some grinding to the head I think the best results are to be had in the combustion chamber - radius the chamber edges, and a mirror polish on the chamber would be worth the time. Should keep deposit formation down and remove hot spots that can cause detonation. The 4.0 seems to be prone to detonation and ping, dont know if its the CC design, or the advance curves the computer throws at it, but either way the CC work wont hurt. (dont change any contours just polish) If you run a chip with more aggressive advance curve it would help also- add a margin of safety.

 

[CodePoet]

I don't want to hijack the thread but i'm curious about this book 410. Has anyone bought it and performed some of the mods it describes? I'm probably not in any positon right now to undertake any major engine mods just curious.

Later
CP

 

[SteveVB]

Originally posted by CodePoet
Has anyone bought it and performed some of the mods it describes?

Yep, I have it, very good reference if you paln to do a rebuild on your V-6. Its a bit dated and weak when it comes to specific 4.0 recommendations, but for short block and early 4.0 head prep it is worth the cost. Anyone who rebuilds their 4.0 needs all the info they can get, and this is a good source.

 

[rocklaurence]

I found that the areas around the upper intake were close enough and the gasket was so thin that I left it a lone. However, I did gasket match and open up the lower intake. There was a lot of material around the injector bumps that I removed and I opened up the floor to compensate for the injector obstruction. I used a kit from a performance shop ($30) and did it myself (aluminum is soft). IMO, gasket matching should always be done.