Ported Head

Canadian FJR · Dec 30, 2011

I did a quick search but found nothing. Has anyone had their FJR heads ported and polished. I'm curious how much more flow can be found. The next obvious step would be to have the cams modified.

Canadian FJR

Bustanut joker · Dec 30, 2011

I don't recall ever seeing anything like that being done Scott... However, Carver will have his off soon maybe we could persuade him into something like this?

Ignacio · Dec 30, 2011

Canadian FJR said:
Has anyone had their FJR heads ported and polished. I'm curious how much more flow can be found. The next obvious step would be to have the cams modified.

Not that I remember. You'd be the first. Report back your results.

RaYzerman19 · Dec 30, 2011

I don't know that I'd mess too much with an already good thing. It's already primed up as a performance engine. You may gain a couple of horses, but you are restricted by the size of the exhaust headers and the throttle bodies. Next thing you would have to do is mess with the fuel mapping, all of which is going to consume more fuel, less range, and possibly cause driveability problems/changes that no longer make it the smooth sport touring machine it is. Especially if you changed the cams. Personally, I'd maybe polish, but how long does polishing really last when you'll get a fine layer of carbon deposits on it. I'm sure there are experts who know (oh yeah, I'm an expert - ex is a has-been, and a spurt is a drip under pressure) better than me. I just think you'll end up with a lot of work and expense for little gain or possible degradation in driveability.. just my humble opinion.

Whazzup anyway, too much white stuff in Alberta you're looking for something to do or drain your wallet....... ?????

yamafitter · Dec 30, 2011

I would pretty much have to agree with Ray on this one. In the old days polishing was a good way to improve airflow through the head but with the modern casting techniques the passages are pretty smooth right from the factory so any gain will be minimal IMHO. There may be something to gain with a custom valve grind to smooth the flow around the valve. I had a friend that built modified dirt track motors and they would cut seven different angles in an attempt to get close to a radiused bend on the valve seat and still be within the rules (sort of

). The downside to doing this is that you will decrease the seat area of the valve which increases wear. This is not a concern with a race motor that is being constantly torn down and refreshed but is not good for durability.

As most will tell you the first place to start with an EFI motor when looking to improve power is with the ECU. Modifying the fuel map to match your particular bike and environment is the best money to spend. UselessPickles has already done a ton of work in this area and I would be inclined to contact him and then book some local dyno time to dial everything in.

ionbeam · Dec 30, 2011

I also agree with Ray. And, since it's Friday I'll mention that losing 10 pounds would probably produce more noticeable acceleration improvement than a port 'n polish on the FJR. I've had the head off and was able to look down the ports and at the valve bowl area. There is some polishing that could be done to blend and knife edge the dividers between the valves but not much else.

FJRMGM · Dec 30, 2011

lots of time and effort and $$$ for not much improvement.

But hey, its your time, effort and $$$ so go ahead and be sure to report the results.

Powerman · Dec 30, 2011

I could see a little clean up, you won't get much.

Porting isn't as easy as it may seem, I have a flow bench in my garage.

I never want to be first, there's a lot of trial and error.

If you have a pile of heads you can experiment.

There's a tricky balance between flow and velocity.

Big flow numbers don't always equate to horsepower.

I could see a re-ground cam and some higher compression,

but that would mean high test and more of it.

wfooshee · Dec 30, 2011

Powerman said:
I could see a re-ground cam and some higher compression,

but that would mean high test and more of it.

For the strip or track, maybe. And I mean maybe. For the street, not a chance in hell. Not me, anyway.

Why (possibly) give up all-year reliability, silky smoothness, and economy for an undetectable power gain that means absolutely nothing at 70, 80, or even 120, miles per hour?

Bustanut joker · Dec 30, 2011

Ok Ok Ok So it's a complete waste of time. the manufacturing process has advanced to the stage we are now forced to accept nothing can be done to remotely give us an edge.

Guess me putting mothballs in the tank isn't worth killing the little fukers for the miniscule increase in performance then.. The tree huggers are now going to be knocking down me door!

HotRodZilla · Dec 31, 2011

Bustanut joker said:
Ok Ok Ok So it's a complete waste of time. the manufacturing process has advanced to the stage we are now forced to accept nothing can be done to remotely give us an edge.

Guess me putting mothballs in the tank isn't worth killing the little fukers for the miniscule increase in performance then.. The tree huggers are now going to be knocking down me door!

I don't think that's it Bust. If you're gonna race the motor and be willing to take it apart every few hours of use, it would probably be worth the work. BUT...as already pointed out, porting and polishing to max gain is going to take some practice and trial & error.

Who wants to do that with their road bike? If you're playing a game of tenths of seconds, its worth it. For what we use them for...No way.

Canadian FJR · Dec 31, 2011

Thanks for all the comments. I have worked with a very good engine guy in the past. This has included both street and race engines and I have full confidence in what can be done. It comes down to time and money. If I can find a head at a reasonable price I will let him play with the flow a little and report back.

Canadian FJR

LAF · Dec 31, 2011

If I had the head off and had someone close I would let them flow it for sure. The issue comes with cams. You would probably need to go bigger on the valve seats and valves and new springs to handle the lift of the new cam. Then you have to get it fuel and not sure what the max flow of the throttle bodies are. You could overcome that a bit with bigger injectors, but then you may need more fuel pressure, and then a good dyno to dial in a Power Commander.

If I had a friend and it was off I would have it flowed. Cant hurt. And I have no idea what kind of valves, seats, and springs are in there but there are some very good valve sets out there that could improve on things.

Effort verses the gain would be the big question but to flow a head is a good thing and may help equalizing the throttle bodies on a sync.

wfooshee · Dec 31, 2011

If something happened that needed the head to be pulled, I'd probably be searching eBay for another motor. Like others have done after CCT issues.

falsus nomen · Sep 16, 2016

WHAT? What are you all talking about. If I ever have the head off, the first thing I would do is have it ported and polished. If you have ever worked with racing vehicles of any type, you know that even ok stock work can gain a lot with a basic p&p.

"OH, I looked down the intake it doesn't need it." WTF are you even saying. ANY stock casting can do with cleaning and smoothing. On any engine.

ionbeam · Sep 16, 2016

Well, allrighty then, the falsus nomen Flying Pig Project

How to make 650 lbs fly quicker, faster and higher.

All hot rodding items on the table. First, let's design the project (OMG, an engineering plan on which to stage a project). First, what target power level are you aiming for? What kind of Sport/Tour driving experience will the upgraded engine provide? Will the torque and HP come from more top end RPM or lower RPM breathing? What goals are there for fundamentals like piston size, rod stroke, combustion chamber volume & shape, valve size, compression ratio and cam profile? On the secondary items, how will the fuel mapping take place and how will you get an aftermarket ignition controller installed? Once all this is settled, it's time to look at air intake, intake runner length, header shape, length and exhaust system. While thinking things over, it's also time to dig out the plastigauge, micrometer and scales for a little blueprinting and balancing.

On the other hand, I'm pretty sure that an inexperienced person could do a fair amount of harm if they try to do shaping beyond just polishing. I have had the cylinder head off my '04 FJR, I've looked at the intake runners and cylinder head pockets (hardly a pocket) and decided that the 2 - 5 hp wouldn't be worth the work.

Look at all that opportunity to polish! Man, just makes ya want to break out the pneumatic hone... It sure makes a feller want to smooth, blend and knife edge ****.

Viper Pilot · Sep 16, 2016

Why not look into turbo charging? With the relatively low compression I would think just some exhaust fabrication and custom dyno tuned fuel map would be the fastest way to boost up the power. Folks with Busas did this many times.

fljab · Sep 16, 2016

Hey, my thoughts are if you have the head off, or have a spare, and want to take the time or know someone you trust, it can't hurt to do some cleanup of the head. Smoothing out the passages, port matching, and bow blending behind the valves are all things that do help in many cases. I do think, as has been said above, that if it's done wrong it can hurt, but WTH, go for it.

It does get you on the "slippery slope" of how much to do and what is too much. I know my old 100K mile + stock '09 is plenty fast for me and I like how it will run anything for fuel and if you have a situation that you must use power to get out of, a gear or two will pull up the warp drive and get it done.

Can that be improved? Yes, and maybe, it's just not something we normally do because of the nature of the beast that FJRs are. This means you can be a true FJR pioneer! Let us know how it works out.

Bustanut joker · Sep 16, 2016

ionbeam said:
Well, allrighty then, the falsus nomen Flying Pig Project

Why do you get yourself into these mind boggling debates Alan?

You know no matter what you say you're going to get the hard heads who don't understand logic or facts.

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