Port and Polish?

[ft_sjo]

If you don't go ITB's or carbs then you're unlikely to have any gain by porting the heads further.

[NomoreNA]

Every cylinder head I have seen has always had tons of room for improvement. I don't see why the FA20 would be any different.

[naikaidriver]

Originally Posted by NomoreNA

Every cylinder head I have seen has always had tons of room for improvement. I don't see why the FA20 would be any different.

That's a pretty broad stroke.

Do you now, or have you ever done head work for a living?

Scott

[cplabaunza]

Could try milling the heads also while your at it for higher Compression Ratio if you plan on staying NA

[swift996]

That with some more aggressive cams (and supporting valve-train) would be nasty. It's just a lot more difficult compared to an inline engine because you have 2 heads and need to remove the engine. So it's going to be costly, but I'm waiting to see someone do this!

[NomoreNA]

Originally Posted by naikaidriver

That's a pretty broad stroke.

Do you now, or have you ever done head work for a living?

Scott

Yes I have done cylinder head work on everything from domestics to pro street drag bikes. I am also a lead machinist for a dev team that was recently blessed with the task of designing the worlds most efficient natural gas turbine.

[naikaidriver]

Originally Posted by NomoreNA

Yes I have done cylinder head work on everything from domestics to pro street drag bikes. I am also a lead machinist for a dev team that was recently blessed with the task of designing the worlds most efficient natural gas turbine.

Well, I was just a simple, part-time, "tuner" 20 years ago that worked in a small shop working on engines for drag cars. Nothing like your resume obviously.

I guess I will just shrug and walk off.

Scott

[FirestormFRS]

Porting and polishing will make obviously make the air flow more efficiently if done correctly. Just not sure you'll move a large enough amount of air to get the type of gains you're looking for. Cost vs. reward just isn't going to work out imho.

[russv]

What would the horsepower gain vs cost be? Prohibitive!

[mswhong]

Originally Posted by Hawk77FT

How about doing just the ports? cyl head - intake and exhaust, and intake manifold, and exhaust. The intake is plastic? WTF?

There's heaps of cars being made recently with plastic manifolds.. i assume this is to prevent heatsoak from a metal manifold.

[swift996]

Originally Posted by mswhong

There's heaps of cars being made recently with plastic manifolds.. i assume this is to prevent heatsoak from a metal manifold.

Cost and weight are usually the drivers with plastic. Cars will become more and more plastic base as fuel economy regulations take place.

[mad_sb]

Originally Posted by dwx

The intake manifold is plastic so good luck with that one.

....

Extrude hone.... assuming the runners are smaller than the ports of course.


@Hawk77FT you are talking about a huge investment of cash and down time. The motor has to be pulled out, torn down, put back together, and re installed.. not to mention the cost of the actual PNP work, which will cost a good bit if your going with a reputable head-work shop.

Probably the lest gains per dollar you could do at this point in time. If the motor were going to be out for some other reason and torn down... then sure go ahead.

You would be far better off (power per dollar) to just do a supercharger kit. Probably cost about the same or even less as well.

I'm sure it won't be long before we have aftermarket exchange parts available (pre ported and built heads, cams in various profiles, intake manifolds) as well as modified stock parts. At that point the whole idea becomes more feasible imo since the skilled and dedicated DIY guys could then pull the motor and have it back in and ready to tune in a single weekend.

[oldeskewltoy]

I've got a flowbench........

4AGE


7MG


I just need an FA20 head - http://www.ft86club.com/forums/showthread.php?t=47375



Oh... btw.... there is some inaccuracies.... the smoothness of the ports surface for one..... when you have a carburtor, or T/B injection where the air and fuel are mixed before the head... then I more or less agree that a "textured" surface (80 grit) helps keep the air and fuel atomized.... but the FR-S has a mixture of injection system...neither of which has the air and fuel mixing before the head.... so the ports in an FA20 head should be a lot smoother... (200 grit)

Exhaust ports should be as smooth and reflective as possible....

4AGE exhaust port - before and after.......

[rusty959]

Originally Posted by oldeskewltoy

I've got a flowbench........

4AGE


7MG


I just need an FA20 head - http://www.ft86club.com/forums/showthread.php?t=47375



Oh... btw.... there is some inaccuracies.... the smoothness of the ports surface for one..... when you have a carburtor, or T/B injection where the air and fuel are mixed before the head... then I more or less agree that a "textured" surface (80 grit) helps keep the air and fuel atomized.... but the FR-S has a mixture of injection system...neither of which has the air and fuel mixing before the head.... so the ports in an FA20 head should be a lot smoother... (200 grit)

Exhaust ports should be as smooth and reflective as possible....

4AGE exhaust port - before and after.......

I don't understand how a port injector isn't mixing fuel before the head.