tri z 250 cool head and vforce 3 install pics

[pcs]

ever since i decided to build up my tri z, ive found that some of the info about parts is a bit sketchy or not easily found i figured ill help others that come along and have question on certain parts by posting pics up of what i buy and maybe ill save them time.
here are pics of the part #'s direct of the v force cage that is going into my tri z and pics of the cool head i purchased and a few side by side of the parts they are replacing.

[pcs]

here are pics of the head, i went with the pump gas dome for now since the cylinder isnt ported.

[Jcormode]

Nice parts cheif who did the head?

[pcs]

i ordered the head like that, its a pump gas dome.

[pcs]

got it from off road innovation

[Mosh]

Nice parts cheif who did the head?

got it from off road innovation

The heads were produced by Corey Sprock back in 2006-2007 and the first runs were all plain aluminum. Later another member here (Honda250sx) took some of the natural aluminum heads and anodized them for Sprock.
You can read up on the development here.

http://www.3wheelerworld.com/showthr...-more-new-pics

here are pics of the head, i went with the pump gas dome for now since the cylinder isnt ported.

During the initial design it was thought that the first runs of domes would yield different performance gains. Once the heads made it into the field for further reports, it was found that the "pump gas" domes were barely that. Unless you have your exhaust bridge raised to lower compression, or you re-chamber the "pump gas" dome you have, more than likely you will find that even with 94 octane fuel you may have some pinging or detonation. In most cases, if you make no alterations and run that dome as it sets, you will need a minimum of 50-50 93 octane and 110 race fuel to avoid detonation.
Any domes higher in compression and squish, or shall I say smaller in CC's than Sprock's "pump gas" dome designation, were significantly high on the compression chart and will require 100% race fuel. It has been my experience that the Z does not like tight compression without significant squish changes and dome alterations, a science which Yamahondaman had nailed down packed, but unfortunately those secrets went with him when he passed away. (Most on this forum would consider him the king of Tri-Z horsepower gains) Yamahondaman that is.

The VF3 reeds were also developed / found through Sprock a few years later during big bore Z development, when another rider not on forums, shared the info with Sprock and I, that the 2006 KX125 used the same mounting area as a Z jug and was later refined through Moto Tasanari aka V Force, to be altered slightly to fit the Z engine specs. Those work well with or without the factory Boost Bottle IMO.
Before then, some members found that WR 250 cages fit the Z in which you could get them in the VF2 design before the 3's came along.

There is loads of history on this forum about the Z and parts being altered/made to fit.

[pcs]

thx for the added info mosh, according to offroad, they also mention that people who had ran the pump gas dome still had to mix in race gas, which is what i do anyways.

[christph]

Yeah, thanks for the history Mosh. I wish I have known the "pump dome" was really a 50/50 dome, it would have saved me some grief. I did a lot of mods all at once so I had trouble figuring out what the problem was. Now it runs great--much better than I thought a Z was capable of.

[Rigaman]

Does anyone have info on how to modify the pump gas dome to make it run on pump gas? How much power would be lost?

Also.. Do you use a special head gasket with the cool head?

[Just-Tri-It]

Mosh, are you saying that with either of the domes that come with it, there are still mods that need to be done to the dome for it to run 93 successfully and not have detonations?

[3 Wheel Drive]

Does anyone have info on how to modify the pump gas dome to make it run on pump gas? How much power would be lost?

Also.. Do you use a special head gasket with the cool head?

You can save yourself some time and $$$$ by just using your OEM stock head, right? Keep the high compression domes for when you want to run 112 octane... IMO. One day they may not be so readily available?

I was going to track down a pump dome but decided not to cause my stock one works fine. The cool heads use rubber re-usable o-rings, no need to keep paying for new gaskets if you use them.

[Rigaman]

But if I switch from a stock cylinder to a cool head, I will have to keep changing head gaskets when I put the stock head on.

I would much rather have a good dome that I can use for pump gas, and another for race fuel.

[badass350x]

Looking good buddy, I guess this explains why you were not at invasion 2013????

Dean

[Bryan Raffa]

got any pic's of the bottom of the cyl,,, when it was off? last I knew cory had blank domes!

[pcs]

yes it does badass350x: took to long to get parts in. i was hoping to at least have the reeds and the carb in but they were shipped via usps and they are horrible! got a pwk keihin and a swinger in the works now
the cool head does not run a head gasket, it uses o rings as mentioned above and any of the domes can be machined down to reduce compression.not much of an issue or difficult to have done.i have also seen people run a thicker base gasket too. i personally dont run straight gas 91 bc it has ethanol in it and ethanol likes to pull moisture from the atmosphere and when it combines with water it will separate from the pre mix and when that fuel goes in to the motor it provides no lubrication for the motor. race gas do not have ethanol and doesnt have this issue.