DIY Port Jobs

[johnmarchetta34]

I am going to attempt a DIY port job on my SJ using the wax template for the 1st time. Can anyone post pics/ other useful info for me so I can know what it should look like?

 

[fastgtfairlane]

The wax templates all uss a 0 deck height. So if you go that route, you'll want to bring the cylinder to a 0 deck height so the ports line up. I printed the wax files out of curiosity to compare to my ported cylinder. The 0 deck height is done to lower the squish and ensure a flat top surface. Also be very careful with the transfers. The material between the water jacket and port is very thin. Ive also been doing some research as I have a spare 62t engine that ive considered doing some port work on.

 

[johnmarchetta34]

The wax templates all uss a 0 deck height. So if you go that route, you'll want to bring the cylinder to a 0 deck height so the ports line up. I printed the wax files out of curiosity to compare to my ported cylinder. The 0 deck height is done to lower the squish and ensure a flat top surface. Also be very careful with the transfers. The material between the water jacket and port is very thin. Ive also been doing some research as I have a spare 62t engine that ive considered doing some port work on.

How much above 0 is a stock deck height?

 

[fastgtfairlane]

Not sure exactly but looks to be between .020 and .040

 

[kevbo]

Are you wanting to go fast or have good response? Don’t raise the port much unless you are okay with slow throttle response.

 

[Storbeck]

I really appreciate Wax and the things he does, but if this is your first time and you're not feeling confident, I would use the yamanube templates.

For a couple of reasons.

The biggest thing is that WAX templates raise the transfer ports quite a bit. He does it for good reason (to balance with the higher exhaust port) but for a first time port job the transfer ports are WAY more tricky than the exhaust.

The Wax templates use a fairly high port timing. That's because they're meant to make a lot of power. I am not a "you gotta have that low port for the low end hit" kinda guy, but low ports for strong bottom end IS the conventional wisdom and it is that way for a reason, you are venturing out on your own to some extent using that high timing, and you should be prepared to know what you're doing with the rest of the motor, the compression and the ignition and the tuning, to get it to work together as a system. 195 degrees is going to be more tricky than 182 especially when most of the people you talk to are running 182 ish so that's what the "normal" tuning is going to be based on.

If you're just looking to get a bit more out of a typical basic superjet with a b pipe and 38mm carbs and stock ignition I would choose the much milder Yamanube template. That port, an ada head, a b pipe, and a zeel, and you have a pretty decent combo that is stupid easy to tune. I have one just like that myself.

You can do a quick yamanube exhaust port with a run of the mill die grinder and a carbide burr from amazon really easily, and it will work fine with stock transfer ports on a 62t cylinder.

 

[johnmarchetta34]

I really appreciate Wax and the things he does, but if this is your first time and you're not feeling confident, I would use the yamanube templates.

For a couple of reasons.

The biggest thing is that WAX templates raise the transfer ports quite a bit. He does it for good reason (to balance with the higher exhaust port) but for a first time port job the transfer ports are WAY more tricky than the exhaust.

The Wax templates use a fairly high port timing. That's because they're meant to make a lot of power. I am not a "you gotta have that low port for the low end hit" kinda guy, but low ports for strong bottom end IS the conventional wisdom and it is that way for a reason, you are venturing out on your own to some extent using that high timing, and you should be prepared to know what you're doing with the rest of the motor, the compression and the ignition and the tuning, to get it to work together as a system. 195 degrees is going to be more tricky than 182 especially when most of the people you talk to are running 182 ish so that's what the "normal" tuning is going to be based on.

If you're just looking to get a bit more out of a typical basic superjet with a b pipe and 38mm carbs and stock ignition I would choose the much milder Yamanube template. That port, an ada head, a b pipe, and a zeel, and you have a pretty decent combo that is stupid easy to tune. I have one just like that myself.

You can do a quick yamanube exhaust port with a run of the mill die grinder and a carbide burr from amazon really easily, and it will work fine with stock transfer ports on a 62t cylinder.

I greatly appreciate the advice. Im gonna go this route i think

 

[Trevorbm]

I second this. Yamanube template and clean up the transfers and port the cases. Pretty diy friendly

 

[waxhead]

Tell me the port height you want and I’ll set one up for you. I always run zero deck height because the Yamaha is massively under-squished from the factory. As an engine builder, I’d rather correct that properly from the start.

Honestly, I don’t even know the stock deck height — I’ve never bothered checking because it’s irrelevant once you’re doing it right.

So just let me know your target numbers and I’ll make a template with a lower exhaust and transfers… and then go cry myself to sleep.
Ha ha

 

[Storbeck]

Kawis are way worse! Yamaha is at least close enough that with an o ring head to avoid the thickness of the gasket it is physically possible to get a good squish clearance. Kawis are ~.055" down the hole.

 

[kevbo]

Another plus of low ports is that they will work with almost all available impellers and exhausts, even stock. You need to be an accomplished engine/pump tuner to make high port cylinders work well, especially on pump gas.

 

[waxhead]

Another plus of low ports is that they will work with almost all available impellers and exhausts, even stock. You need to be an accomplished engine/pump tuner to make high port cylinders work well, especially on pump gas.

To be fair thats becasue they pretty much are stock with the low porting.