Port match and polish? 3FE

[RockDoc]

I am planning on doing a de-smog on my 3FE soon. Would it be worthwhile to pull the manifolds to port-match and polish them while I am working on things? I was thinking just the manifold side, but is there any safe way to port-match the head with it in the truck?

I realize this isn’t going to yield massive benefits, and the stock manifolds are pretty good, but…...? Given that I rarely rev it above 3500 rpm, would the gains out-way the effort? Worth doing without modding anything else (already catless)?

Thanks for your opinions,
Curt.

 

[CruisinFJ60]

do u have a reason not to do it? i mean if ya do it and nothing happens then you only wasted tome time right.

 

[agent orange]

i dont think you could port a head in the truck without getting your chambers full of metal shavings.

I dont think you will see any gains. I think a good 3 angle valve job and a back cut on the valves would help.

 

[overhanger]

i dont think you could port a head in the truck without getting your chambers full of metal shavings.

I dont think you will see any gains. I think a good 3 angle valve job and a back cut on the valves would help.

Agreed. Porting, even simple port matching work, should never be attempted without removing the head from the truck. It's tedious enough work with the parts on a bench, I can't imagine the hassle it would be with the head secured to the block.
On the other hand, anything that allows for better flow of air can be beneficial in producing more power from an engine - even the 3FE. Port matching will show some gains in power. Whether the gain is enough to warrant the tedious, dirty process is up to you.

 

[brokenparts]

ah, you guys are crazy... this is how to do it.

http://www.audiforums.com/m_693578/mpage_1/key_/tm.htm

 

[overhanger]

ah, you guys are crazy... this is how to do it.

http://www.audiforums.com/m_693578/mpage_1/key_/tm.htm

Oh man, that's a beauty!! Darwin award, anybody?

 

[cruiser88]

dam

 

[NocalFJ60]

ah, you guys are crazy... this is how to do it.

http://www.audiforums.com/m_693578/mpage_1/key_/tm.htm

Brilliant

 

[Moby]

My 3FE head was pocket ported and gasket matched as part of my rebuild. As others have said you can't do port the head with it in place. You could gasket match the upper plenum to the lower and the lower to the manifold gasket but that's it. Don't do anything to the head with it in place.

 

[RockDoc]

Pretty much what I was expecting. Can't hurt to pull the manifolds and intake chamber to match them to the existing profile of the head ports as much as possible and polish them. Don't even think of touching the heads on the truck, unless you want to become infamous.:whoops: (F*** that was a knee slapper!)

 

[Wile E Coyote]

My $0.02,
Gasket match the exhaust manifold ports, remove any casting flash, etc. and call it a day.

 

[Moby]

My $0.02,
Gasket match the exhaust manifold ports, remove any casting flash, etc. and call it a day.

Completely gasket matching the exhaust manifold is kind of a debated topic. The argument against is that while you don't want any flow interruption from the head out into the manifold you do want interruption from the manifold back into the head to help prevent reverse flow. It's common to have the bottom of the exhaust manifold runner below the bottom of the exhaust port in the head and then matched on the sides and top. At least that's the theory that I've been told, take it for what it's worth. In our engines there probably isn't a noticeably difference either way.

 

[RockDoc]

"It's common to have the bottom of the exhaust manifold runner below the bottom of the exhaust port in the head and then matched on the sides and top."

If I do this, I dig out some texts I have with fluid flow principals. Having a sharp step up in the width of flow (i.e. wider on manifold side) should introduce turbulance, which would be bad..... Unless this helps to stear the flow downward and around the bend. I think this is where the idea of "dimpling" on bends comes from, like on a golf ball, it allows a higher flow before developing flow separation and turbulence, blah, blah, blah.

 

[vipergrhd]

extrude hone

have any body heard of extrude hone?from what i can gather it is some kind of media that they pump into intakes,heads etc.to make it flow better it even comes out polished.don't know the cost of doing this.check out the web site. john

 

[overhanger]

have any body heard of extrude hone?from what i can gather it is some kind of media that they pump into intakes,heads etc.to make it flow better it even comes out polished.don't know the cost of doing this.check out the web site. john

That is what the Audi guy was trying to accomplish only in a bassakward way! Extrude honing, done properly, does good things.

 

[longtimecruiser88]

3FE porting

When i rebuilt my 3FE I did a full port, polish and gasket match. Now mind you i did this engine from top to bottom (spun a rod bearing) I havnt taken it to a dyno but I have noticed a power gain, I have been doing other work to it so i havnt had it on the road long so i dont know what kind of a change in fuel mileage it gets but I think its definatly a good idea to get some more out of those 3FE's

 

[agent orange]

When i rebuilt my 3FE I did a full port, polish and gasket match. Now mind you i did this engine from top to bottom (spun a rod bearing) I havnt taken it to a dyno but I have noticed a power gain, I have been doing other work to it so i havnt had it on the road long so i dont know what kind of a change in fuel mileage it gets but I think its definatly a good idea to get some more out of those 3FE's

When you say full port job, how much material did you remove and where? I havent had the head off of mine but i imagine you could shave the roof and profile the guide, that works on about every head.

-Matt

 

[tntoyota]

That things got a really low comp ratio, seems (to me) like you'd only notice a difference with more air popping out/ high RPM's? Like compression breaking with a 11:1 and a 7:1 there should be a noticeable difference...


Chilton's manual has the 3fe at 8:1 comp ratio. (makes a great turbo motor )

Not saying it wouldn't be worth it, the way I see it every little thing helps but much can go wrong if done wrong. Too much port, If the ports are not all the same size, same shape....For the port to be effective all the ports must be the same.

Its a NON cross flow head I would be worried about taking too much/ warpage? (Yes I realize its Iron and that would be hard)


I plan on a simple 2fe don't really see a P&P benefit, but if I go high comp with it I would too do a P&P.

 

[matt.mcinnes]

Might be of interest 3FE head ported and polishes with over sized Ferrea flat faced valves, flow tested before and after.

https://forum.ih8mud.com/80-series-...t-polish-flow-test-results.html?highlight=3fe

 

[mmw68]

Randy did this to my 3FE, and I think along with the high flow muffler and new injectors, it made a big difference
https://forum.ih8mud.com/60-series-wagons/191480-another-fj62-engine-swap-randy.html. I plan to bore out the TB as well.