Port and Polish

So i did a search and came up with a couple things regarding the question i have but it wasnt fully answered.

Has anyone ported and polished the throttle body and or heads in the 4.0l engine yet?

ive been looking at doing the throttle body and was wondering about the heads during my brainstorming lol

 

well i guess the reason why i didnt find anything is because no one has done it?

 

Never heard of it, I would hope modern engines have ports that line up well enough to not need port and polishing.

 

It's too much money for maybe a gain of 10hp. And that's the most you'll get I'm sure

 

I'd bet money he would see less than 1 hp.

 

Haha you're probably right. I was just givin a rough estimate. My buddy did it on his Acura tl type s. it was real expensive and the put it on the dunno and got 7 more hp. I couldn't help but laugh

 

You can port and polish the throttle body by yourself with a few simple hand tools.

 

wasnt sure if anyone had done it and i was thinking about doing it this weekend and doing a write up

 

Already have nothing there either.

 

Just for clarification, what is being propsed here is not "porting and polishing". That process involves enlarging the ports and or intake runners and balancing said components to achieved increased and balanced CFM to each cylinder. There are very few guys who have the know how to do this and have the equipment to flow bench test the final result.

What we are talking about is simply polishing and cleaning up the intake manifold and throttle body with some minor gasket matching where the parts go together.

On older vehicles with rather crude sand cast manifolds this process often did yeild noticable results. You often found rough surfaces, jagged edges and mismatch between manifold port and head port. Modern engines are generally a lot better in all regards.

There is no question that polishing these parts on a 4.0 would flow more air. Whether it would be enough to actually feel anything is questionable.

Here is a thread claiming "much better acceleration and throttle response" from this work. He does not provide any dyno results. My policy is to place such claims on the suspect list unless proper dyno work was performed. Personal impressions regarding engine HP gains have no currency with me. I don't even trust my own impressions!

http://www.xr-underground.com/forum/showthread.php?t=38047&highlight=intake+plenum

 

I've read that thread. Although it is questionable by the seat if the pants hp gauge there is hp to be gain by doing this mod to any vehicle. U increase the airflow in a motor u increase the efficiency of it. Hints the reasons for CAI, headers and exhausts. If I could find a set of donor heads intake manifolds I would do this and get a true estimate of hp of some dyno pulls. Only thing is is trying to find the parts.

 

I would say all intake & exhaust ports (where applicable) benefit from obstruction free passages, def. noticeable in carburated engines , not sure with EFI seeing how a pre determined amount of fuel is injrcted (under pressure) at a pre determined time..

 

Don't have anything to do really wig the EFI I would think but more the the flow of the air in and out of the engine. Once I can find the pieces needed I would love to do it it may work and ot may not work.

I know a couple engine builders that do the work to include valve jobs. If anything this mod may help the truck out for those who are boosted

 

Here you go. I'm sure this company could tell you;

http://ttcperformanceproducts.com/1gbucyhe.html

They look great, but they are way way overpriced.

 

Alright I had got an update on the porting and polishing of the heads for those of u who might be interested.

There is a guy the is a well know engine builder in Mexicali that can P&P the heads for $200. There is a member here that has had it done and said that there is a noticeable difference in the way the truck runs and sounds. He also stated that the throttle response fells quicker as well as the acceration im looking into having this done here in a couple months to my truck but before I do I would like to get it dynoed for accurate hp numbers.

Thoughts?

 

If you open up the throttle body you'll need a bigger throttle plate. $200 to polish and port a head is not bad but that is not where the expense is. You gains will be minimal the intake ports are not long enough to make much if any difference. Buy a supercharger.

 

Sup guys, I'm porting my throttle body on Tuesday, Ill let you know if theres a difference.

 

errbody here hates on CAI and port and polish because of minimal results, but when you add up a few mods, and you roast the pos chevy next to you....Priceless!

 

im looking at doing mine Sunday maybe along with a cab mount chop. i know when i looked at the TB there was a noiceable lip in there.

You would be surprise on how much a P&P of heads actually helps not only stock but boosted engines

 

Sooo I'm assuming nobody has done it.. I'll let you all know this coming Friday. Gonna port polish and some other stuff..