Originally Posted by $tonecold

The cam plate and oil pump don't affect performance. As to whether it is worth the extra money is up to you. There are many factors that can determine how much power you will make with any performance upgrade. Some of it will depend on the person doing the installation. If they just install the kit without taking any measurements the compression ratio may not be what was advertised. I have heard of some of these kits having deck heights where the pistons are up to .020" below the deck. That will lower your compression from 11:1 down to 10.6:1. That could have a significant bearing on the final power results. Also there is the volume of the heads that needs to be determined. I have been told that the head volume on an M8 can vary from 85cc to 90cc. If you get low deck height combined with a large combustion chamber now your compression is down to 10.3:1. So how the components are put together can make a difference. The lower deck height will also negatively affect the squish area and the swirling of the fuel mix and can impact performance.

After all of that the cam you choose might not give you the performance you're desiring. The exhaust, throttle body, air cleaner, and tuner (hardware and the person doing the tuning) all play into it. So asking whether the Fuelmoto or S&S kit is going to perform better is relative to a lot of variables.

As for cost Eastern Performance, Direct Cycle Parts, or Parts Giant may give you better prices if you call them. On the other hand, Fuelmoto is already lower on price and they do have really good support after the sale which you won't get at the other three vendors.

So the answer to your question is the numbers will vary with the build and builder and cost can and will vary also. Basically these kits are going to make enough power that the big problem will be keeping the rear tire glued to the pavement anyway, even if it's not the top numbers on the forum.

Originally Posted by Trainwreck43

Someone buy this kit and give us a real Dyno/review! Only thing that turns me off is the dip in torque on their stock Dyno sheet. Wonder if there's an exhaust combo that tunes that out.

Originally Posted by Ridetothehill

Thanks Mark, I did not know of the chamber size differences of the M8. Have heard of folks concerned with decking an deck heights, but didn't know why. This was the missing piece of my build plan. The numbers of ba70's build are quite impressive. Im shooting for 150/150 in my build plan and to get this Iv'e been focusing on the right combination of periferal components.

Again, thanks to all on this forum,
Ralph

Originally Posted by $tonecold

The variation in chamber size is not from personal experience, I was told that by someone that deals with this much more than I do. The spec'd chamber size is 86.5 cc, that is what is used for calculations by CP and other vendors when they engineer pistons for the M8. If your using a calculator to figure static and dynamic compression that is what you would put in unless the heads you are using have been cc'd and you have a real number. The compression on the big bore kits is figured using the stock head gasket also, which is .045. DTTJGlide was saying that the compression on the kits is figure taking into account that the piston is going to be down in the cylinder .010-.020". That's not what I see when plugging in the numbers, but if your piston was down .015" you could bring it back to kit spec by using a .030" head gasket.

Steve told me the cams he has developed are geared to the 117" to 120" big bores. He is planning to do some cams for the 124"+ motors since that seems to be the direction the big bores are headed. By the time you really start your build he should have something ready. I think this is going to get interesting.

Originally Posted by yobtaf103

Stonecold you saying S&S has the comp sorted (11-1 spec) then, just measured the supplied head gasket 0.030" from S&S
so guys zero decking could be over 11-1 ?

Originally Posted by baz70

Here is the Dyno sheet on my bike. I finally had a day off to go check it out and take it for a ride. 158 ft-lb and 123 hp. I went for torque on the build, and it paid off.. She's got some grunt.. tire melting, speedo mashing, arm stretching fun.