Im having trouble deciding on which head to try on my 12 assault. Ive read good things about both but also some bad things. Im going with the 12.5 head cause im riding at low elevation and don't think ill make it to the hills this year anyway. I just don't want to be mixing race fuel so it runs right i just want to be able to run pump gas. I also will be changing my weights i was thinking Mds any other suggestions.
which head par or rktek
- Thread starter granto
- Start date
T
Trenchmaster
Well-known member
I can't comment on the Par head but I did order the RKT kit and the parts all look top notch to me. Kelsey was offering a great price on the Rooster adjustable clutch weights with the kit. Not to sure what the domes cost but looks like it would not be to hard to change them. I ordered the 13/1 domes and hope they run ok at 2800' to 3300' around home with Shell premium.
I don't want to speak out of turn here because I have not run the RKTEK head, but myself, and a couple friends all ran 13.1 PAR heads. We unload at 2000'. I ran 1 gal of 100LL in my tank, and babied it a bit till 4000'. I had no problems with DET. But both my buddies did when really getting on it below 3500- 4000'. Maybe start with a little avgas or race mixed in and decrease till you find your limit, you'll probably be fine, Kelsey knows his stuff and I doubt he'd send you domes that wouldn't work for your main elevation. Just throwing out our findings at lower elevation with the 13.1 PAR domes. Just remember that more compression doesn't mean more horse power, just allows you to keep more of the hp you have as you climb in elevation. Good luck......pray for pow!!! PS. New domes about $80/set for extras
I ran the PAR head on my 12' with 13.1 domes and MDS clutching. Loved the mid range responsiveness that the head gave for throttle control. MDS have been the hardest pulling weights I've used to date, really like them. My riding buddy is now running RKTek and really likes that also. I have RKTek pistons with PAR head on my 13' with rooster weights. The roosters have another hole for more fine tuning. I don't think you will go wrong with either of the heads or weights. Ford vs Chevy. We both run turbo sleds with these set ups, but ran them non turbo also. You can't make a wrong choice in my opinion, go with what's easiest to get a hold of or what your buddies are running so you can swap notes on your set ups to get the most out of your sled.
YOU COULD NOT PAY ME TO RUN AN RKTECH HEAD.
I hope people understand when they make posts like that it helps no one. Write something up that explains what products you've used and what issues you have had and that may actually help someone. For all we know you don't like Kelsey but have never even used his products. I'm not defending RK TEK here as I've never used his products, just sick of seeing this type of response.
X2!
Well said. I haven't used rk tek, (yet) but have a kit on the shelf for this season. So I don't have a dog in the fight either but agree 100% about worthless posts like above.
Well said. I haven't used rk tek, (yet) but have a kit on the shelf for this season. So I don't have a dog in the fight either but agree 100% about worthless posts like above.
I have the PAR 12.5 head on my 12 Assault and ride sea level the majority of the time. I haven't had any DET issues. Initially I was having some problems where the sled would cut out and the engine light would flash, but that was all caused by bouncing off the rev limiter. I added more weight to my MTX weights and the problem hasn't come back at all. So, no issues here, just add enough weight to keep your sled off the rev limiter.
haven't run with any RKT heads so I can't say one way or the other on those...
haven't run with any RKT heads so I can't say one way or the other on those...
Are these people you ride with that have had PAR det issues or is this info off the web? I know of a couple guys that bought used PAR heads and put them on there 2013 Pro's without consulting PAR first.
I have never had any issues as of yet on my 2013 Pro w/a PAR head setup by them of course.
M
milo303
Well-known member
Couple online, one person I know.
So I don't know exactly what the reasoning was but the guy I know gave up and went back to stock
I'm super curious to see the solutions to any det problems.
I personally just installed an rk drop in so I have no personal experience with either, but info is appreciated
So I don't know exactly what the reasoning was but the guy I know gave up and went back to stock
I'm super curious to see the solutions to any det problems.
I personally just installed an rk drop in so I have no personal experience with either, but info is appreciated
2
2mileshigh
Active member
I have the PAR ultimate combo. Runs outstanding. One thing to make sure of is Your TPS setting, use a good VOM to set it.. Great midrange for tree riding. Run 9 to 12k elevation.
Head
I have run all different heads on pros I have run rk tech I have run brads head and even the pre updated 08-09 dragon head and on these pros 11-12-13 they are too lean in my testing they all will det in the mid range, if you are gonna run compression you need to add fuel, I have found in my opinion and testing polaris (to meet EPA regulations) has leaned out the mapping to help comply and in order to do this they had to drop the compression because of det, I have done this since they updated the dragons, when you up the compression you have det problems not all the time but several times a day it will put you in limp mode, so to sum up what I'm saying here its lean fuel mapping causing the biggest problems for guys when adding compression it's not the head it's the EPA if you want more power you need a controller. There is some problems with fuel quality but in most cases I have seen its the mapping you can make a stock sled run better just by adding fuel just my .02, also I run the rkt head and love it but anytime you add compression anybody's head you need to add fuel on these pros, there are bone stock 13 that are hitting det all the time where we ride with 91 premium fuel, elevation seems to make a difference the low elevation guys don't seem to have as much trouble as us high elevation guys I ride 8-11000 ft
I have run all different heads on pros I have run rk tech I have run brads head and even the pre updated 08-09 dragon head and on these pros 11-12-13 they are too lean in my testing they all will det in the mid range, if you are gonna run compression you need to add fuel, I have found in my opinion and testing polaris (to meet EPA regulations) has leaned out the mapping to help comply and in order to do this they had to drop the compression because of det, I have done this since they updated the dragons, when you up the compression you have det problems not all the time but several times a day it will put you in limp mode, so to sum up what I'm saying here its lean fuel mapping causing the biggest problems for guys when adding compression it's not the head it's the EPA if you want more power you need a controller. There is some problems with fuel quality but in most cases I have seen its the mapping you can make a stock sled run better just by adding fuel just my .02, also I run the rkt head and love it but anytime you add compression anybody's head you need to add fuel on these pros, there are bone stock 13 that are hitting det all the time where we ride with 91 premium fuel, elevation seems to make a difference the low elevation guys don't seem to have as much trouble as us high elevation guys I ride 8-11000 ft
One thing to think about is customer support, I cant speak for either brands on a Pro as I own a cat. Any questions I had about anything, clutching, tuning anything kelsey (RKT) had good answers for me with quick responses.
I've ran rkt dropin kits in 3 of my own sleds, I found they have worked as advertised. kelsy has been quick to respond to questions,and his service after the sell has been great. I also think that his participation on this and other forms is a good thing. that being said some people on here feel like he is a bad guy because he has strong opinions,and likes debate. I personally like the spirited debate. and hope I keeps up. it would be pretty boring around here nobody had opinions. on the topic of det. I'd be interested to know if adding fuel in the mid range would eliminate the need to add race fuel to avoid det issues on the 13s. thnks in advance
I've ran rkt dropin kits in 3 of my own sleds, I found they have worked as advertised. kelsy has been quick to respond to questions,and his service after the sell has been great. I also think that his participation on this and other forms is a good thing. that being said some people on here feel like he is a bad guy because he has strong opinions,and likes debate. I personally like the spirited debate. and hope I keeps up. it would be pretty boring around here nobody had opinions. on the topic of det. I'd be interested to know if adding fuel in the mid range would eliminate the need to add race fuel to avoid det issues on the 13s. thnks in advance
Are you running a 13 without a fuel controller? The 13 is way leaner than the 11-12 adding fuel will make your det disappear I have done this many times, most guys are afraid of them but they are the best mod ( tool) you can buy very easy and very effective I use the boondocker box easy to tune and you adjust right there on the sled no computer the best money spent IMHO, the reason race fuel helps is it slows the burn down. give it more fuel in the mid especially in the lower throttle positions
T
Trenchmaster
Well-known member
13/1 domes were recommended by Kelsey for my local elevation ( around 3000') Apparently the 2013 models do run a bit leaner than the 11/12 models so a fuel controller is required for the 13's to run the RKT kit. I'm hoping that premium 91 octane will be good enough to run the combo I bought with out detonation, if not maybe just switching over to the ethanol plug will be enough to run ok?
Det
I have not run this kit on the 11 but I have run heads on 11-12 sleds all of them have det trouble even in the eth mode not constantly but throughout the day it will go into limp mode a few times, usually it happens when letting out of the throttle in the mid range or cursing in the mid range, they have a lean mid range in the mapping some are worse than others
I have not run this kit on the 11 but I have run heads on 11-12 sleds all of them have det trouble even in the eth mode not constantly but throughout the day it will go into limp mode a few times, usually it happens when letting out of the throttle in the mid range or cursing in the mid range, they have a lean mid range in the mapping some are worse than others
