First off this is going to be long,but it should be worth it.
I had been looking for some one to do some tuning on the Brute Force,and looked around for weeks until finally ATP referred me to Torri Racing in Ocala FL.I am very happy he recomended them as well as the members of this board.Torri Racing has a tremendous shop with lots of showroom,excellent kept and clean work area,and a dyno tuning room complete with window so you can ogle the results and the pulls.They have an excellent and courteous professional staff.No wrench throwing,cussing,or screaming will be heard in the showroom as they don't have any of that nonsense going on in their shop.If service,results,and professionalism are what you are looking for you will not find a better shop or tuning facility.
Now lets get started on some results with how the big bad Brute did on the dyno.Torri Racing tech Richard started with an initial pull with the way I brought it into him.The way I brought it in was with: Stock carb(no jetting or fiddling with since bought new),Bayou snorkle kit(with a 2" to 1 3/4" reducer in the end),stock air cleaner,NGK CR7E Plugs,NGK plug wires,Stock CDI,Muzzy Exhaust with quiet core and screen installed,and a Highlifter Extreme clutch kit(pink/almond/54 weights).93 Octane for fuel.This pull resulted with a rear wheel hp of 34.71.
The next test was to install the VDI and make a pull again in the exact form that I brought it in.The VDI was set on switch two with a custom map I made.The total advance was 36 degrees.No changes other then the VDI itself.This pull resulted with a rear wheel hp of 40.85.
Torri Racing tech Richard suggested plugging in a Moose module with the way we were sitting just for curiousity's sake.His and mine.No changes other then the stock CDI and Moose module.This pull resulted with a rear wheel hp of 40.02.
**** Now here I would like to make a note on this module deal.I have seen numerous posts regarding the subject of modules only work part time.Only if going less then such and such mph.I didn't see it on the dyno and neither did Richard.The pull started at 13mph and actually held a better line with less dips then the VDI.It never signed off.it never quit doing what it was designed to do. I will add more on the VDI/Module comparison later.*********
So after we were done playing to see where we stood Richard unloaded the Brute from the dyno and got to work installing a dyno jet kit.He's fast,and he's good and had it up and running again in no time.Only problem was we had to break for lunch.(I need some more weight over the handle bars so figured it was a good idea)
So back from lunch Richard got it strapped down to the dyno again.Everything remained the same except for the addition of the jet kit,and I also loaded the stock 34 degree map that came with the VDI back in at Richard's suggestion.I would tell you what jets,clip,needle, and other voodoo carb stuff for info ....but I didn't ask.I don't know anything about a carb as I'm an EFI kind of dude so it didn't really matter to me what he did to the carb. as long as it worked.This pull resulted with a rear wheel 42.03hp.
Richard then got to work on the state of tune of the carb. and fiddled around with more voodoo to get a smoother and better a/f ratio.He made a bunch more pulls which didn't result in more hp but resulted in more hp over the whole pull.
Next up was to play with the Muzzy exhaust.So we took the reducer tube and screen out and let the Brute breathe.Result?Dropped the the hp from 42.03 down to 41.54.Next up Richard suggested leaving the screen out but adding the reducer tube back in to the Muzzy.Result was 42.93.So it got back what it had lost and picked up another pony.Good Call.
Believe it or not I cut this post short to the parts that might be of more interest.Richard made a total of 27 dyno pulls today and tried lots of different things to squeeze as much as he could get out of the Brute.Different carb settings,different timing maps,also playing with and without reducers in the Bayou snorkle kit,and various other things.His impressions were he really liked the Brute and it's power and was impressed with it.He also liked the VDI.He liked the fact it was programable and felt it ran much better with it.His butt dyno told him he felt as if it had better pull on the bottom end with the VDI and after 27 pulls and his expierience I don't doubt him.He also reminded me sometimes the dyno doesn't tell the whole story as much as the ATV will while riding it.Part throttle power also dosen't show up on the dyno since we were just making wide open bursts,and this is where most trail riders would notice a difference.We didn't do any pulls with torque readings so I can't tell you the torque numbers.The module has it's place and is a very good alternative to a CDI.I personally have ridden and own both a module and VDI.My own butt tells me I feel like there is more low and midrange with the VDI.The gains to be had by A VDI unit are, programability,tach,nitrous retard ability,msd,ability to convert to fuel injection,more torque,and an overall smoother running quad.These benefits of course are for a pretty much STOCK BF.I feel certain there would be more benefits and better hp to be had with a modified quad due to the programable feature of the VDI.It's up to you to decide which is right for you.I would advise anyone looking at a CDI or Module to research them and decide which is best for you and your needs.If it is possible ride and test both and see which you like.I personally still like the VDI and would choose it again as it has growing room for me and my quad,and I like the overall performance better.
So to sum it up I was very happy with the results.A smooth running brute,better power over the entire rpm band, and 42.93 to the wheels.Should make for some fun riding this weekend.Here is a link to some pics
http://pg.photos.yahoo.com/ph/tpslizard/album?.dir=/97ff and I should have the dyno graphs up soon.Thanks to Torri Racing in Ocala Florida.
