PAR Ultimate Pro Combo

[Merlin]

Hello,


I’m currently running the PAR Ultimate Pro Combo(& clutch kit) & am interested in the opinions/feedback from those who are currently running or have first hand experience with this set up…………

Machine & current set up:

2011 Pro RMK 800(163”) – 1200 miles(450 miles with PAR Ultimate Pro Combo)
Riding 3000’ – 7000’ elevation
Rider weight w/gear – 270-275lbs

Modifications & maintenance

Wossner(RK Tek Direct Replacement Pistons) Compression 133/135 PSI w/13:1 PAR head
Yellow injector update (Polaris P/N 4013046-053) w/ecu re-flash
Fuel filter replacement (Polaris P/N 2521095) Pressure 59 – 60 PSI @ idle
Engine mount update kit (Polaris P/N 2204633)
Clutch maintenance(spider buttons to towers re-shimmed to .001”, belt clearance set to .020”, & re-balanced)

PAR Ultimate Pro Combo & clutch kit consisting of:
PAR 13:1 head
SLP pipe & silencer
Power Commander 5 w/SLP stage 3 map(P/N 70-228)
MDS weights(63 gram base weight with 5.7 grams on tip & 2.5 grams in middle)
Primary spring - 120/340(Polaris black/green)
Helix - 58-38-46-ER/58-40-46-ER(Team)
Secondary Spring – 160/240(Team black/purple)


The main issue that I’m having is occasional detonation on the trail while cruising between 6700 & 7200 RPM during light load operation(over ½ but less than ¾ throttle) – WOT operation is fine, no detonation…………Burning 91 octane fuel(as advertised at the pump)……….The 24 ohm ethanol resistor was installed with only a marginal reduction in detonation(if any)…………The pipe & silencer are tight & not rubbing on anything – The springs have been “siliconed” as well……… EV system is functioning properly…………….

After looking at the 70-228 fuel map, which has no fuel added in the above RPM & throttle position ranges, I’m assuming that the detonation may be mostly from a lean condition…………..In addition, despite idling smooth & having good throttle response, the engine seems to run rough as if it were loading up/running rich while riding slow in the trees(4500 – 5500 RPM @ 1/3 throttle or less) - Perhaps too much fuel is added in this range??? Just wondering if others are seeing the same results??? If so, what map changes have worked best for you, if you don’t mind sharing???


The next issue is clutching………. I have noticed that my engine speed has increased 200 – 300 RPM while cruising on the trail over the stock clutching set up which I assume is due to the shallower finish angle on the helix & stiffer secondary spring……..……Despite having gained 200 – 300 RPM on the trail, WOT pulls on hills in deep snow show top RPM to be down 150 – 200 from target(ideal being 8150???) depending on snow conditions with only about a 3 – 4 MPG gain in track speed over stock……….I’d planned on changing the loading of the weights to increase top RPM but considering the change of RPM on the trail & the minimal track speed increase over stock, I’m wondering if the stock helix & spring would be better with a more aggressive finish angle & less spring tension(56-42-36-ER & 155/222)……….


Any info. or suggestions would be greatly appreciated……………



Thanks in advance,


Glen

 

[Bossman]

Par/SLP

Start with clutching changes to correct the shift curve before changing the fuel map. Remove the 2.5 gram slug and move the 5.7 slug to the base of the weight to load the engine harder in the bottom to midrange and get more RPM on top with less total mass. Then you should make a few 15 second runs at 6000 RPM and check the spark plugs and piston wash to see if you need to add more fuel. I have had the best luck with the 140/240 Red/Black driven spring at 5000-9000 ft in most non-turbo applications.

 

[theultrarider]

I also ride a 2011 163 and I weigh about 250 in gym clothes. My motor is stock other than a par 12.5:1 head. I ride sealevel to 7000. Most time is spent at 2-4000.

That said, when I first added the head I had the same midrange det issue as most everyone else did. Step up the Felix to a 62/40 or even a 62/42. The 62 initial angle loads up the motor at slower track speeds and the det goes away. I rode most of last year with 60/40 and overall was very happy since I'm a heavy guy. I went to a 62/42 recently and gained a few miles per hour of track speed while climbing. I haven't run that Felix over about 5000 though. Stock secondary spring. Slip blue/pink in the primary. 68g mtx weights with 3g's in the belly.

Good luck getting yours set up. Betting your det is just needing to load the motor a bit more. More Felix to get it to shift. Then drop weight as needed to get your 's where you want them at wot.

 

[doox]

Tps setting

I had the same problem and called Brad at PA he told me to to recalibrate my tps to factory spec and then set the PC/5 to that if your tps is out of calibration it can run lean and cause detination. This fixed my problem

 

[Merlin]

Start with clutching changes to correct the shift curve before changing the fuel map. Remove the 2.5 gram slug and move the 5.7 slug to the base of the weight to load the engine harder in the bottom to midrange and get more RPM on top with less total mass. Then you should make a few 15 second runs at 6000 RPM and check the spark plugs and piston wash to see if you need to add more fuel. I have had the best luck with the 140/240 Red/Black driven spring at 5000-9000 ft in most non-turbo applications.

I also ride a 2011 163 and I weigh about 250 in gym clothes. My motor is stock other than a par 12.5:1 head. I ride sealevel to 7000. Most time is spent at 2-4000.

That said, when I first added the head I had the same midrange det issue as most everyone else did. Step up the Felix to a 62/40 or even a 62/42. The 62 initial angle loads up the motor at slower track speeds and the det goes away. I rode most of last year with 60/40 and overall was very happy since I'm a heavy guy. I went to a 62/42 recently and gained a few miles per hour of track speed while climbing. I haven't run that Felix over about 5000 though. Stock secondary spring. Slip blue/pink in the primary. 68g mtx weights with 3g's in the belly.

Good luck getting yours set up. Betting your det is just needing to load the motor a bit more. More Felix to get it to shift. Then drop weight as needed to get your 's where you want them at wot.

Thanks,


I'd originally planned on redistributing the weight to load the engine more in the midrange but then I received other suggestions that the helix & secondary spring combo were providing too much back-shift............Either way I go about(weights or helix/spring), I'll trying loading the engine more in the mid-range to see if that reduces the detonation.............

I had the same problem and called Brad at PA he told me to to recalibrate my tps to factory spec and then set the PC/5 to that if your tps is out of calibration it can run lean and cause detination. This fixed my problem

TPS calibration has already been confirmed & I've calibrated the PC5 to the throttle during installation & have checked it several times since - no problems there................

 

[wellfed777]

I'd be interested in hearing what happens if you throw 2 gallons of race in it
and see what happens
i'm running a PAR head (13.6) above 5000 on clear(non eth)91 and it will DET on the trail all the time but with a little race it has not DET once the last two rides at the same place ???

 

[Merlin]

I'd be interested in hearing what happens if you throw 2 gallons of race in it
and see what happens
i'm running a PAR head (13.6) above 5000 on clear(non eth)91 and it will DET on the trail all the time but with a little race i has not DET once the last two rides at the same place ???

I'm sure it would help & it wouldn't be the complete end of the world if it was needed but one of the reasons I purchased the kit was that it was marketed as only requiring premium fuel..............

If race/aviation fuel is required when running these heads to prevent detonation, one would be better off to stick with the stock components & avoid the hassle IMHO..................

 

[Sheetmetalfab]

Det

Both me and my brother experienced trail det with 12.5-1 heads. (Sea level).
Couple gallons race gas or just take it off cures the issue.
Absolutely no other signs of det except limp mode. (Yeah i tore it apart)
A very reputable engine builder explained to me how the domes on these heads are cut too thin and will actually oil can and set off the det sensor.
Took my head off and gained 150 rpm with the exact same clutching. Added a gram and its all smiles now on 90 octane. (All we can get in AK)

He is running the mtntk fix kit
I'm running a long rod.

Definately wasn't from not enough load on the engine.
It would det limp from a steady slow cruise, but never if you held it wide open.

 

[wellfed777]

its a bit frustrating
so i need to run race ($8.00 a gal.) and i void my warranty

 

[just-pinch-it]

Both me and my brother experienced trail det with 12.5-1 heads. (Sea level).
Couple gallons race gas or just take it off cures the issue.
Absolutely no other signs of det except limp mode. (Yeah i tore it apart)
A very reputable engine builder explained to me how the domes on these heads are cut too thin and will actually oil can and set off the det sensor.
Took my head off and gained 150 rpm with the exact same clutching. Added a gram and its all smiles now on 90 octane. (All we can get in AK)

He is running the mtntk fix kit
I'm running a long rod.

Definately wasn't from not enough load on the engine.
It would det limp from a steady slow cruise, but never if you held it wide open.

Ran the 12.5 heads and never seen det once.

 

[Sheetmetalfab]

Det.

Never had a det issue with the stock motor. With the head.
Few supporting mods still no issue.
Little motor work so it actually runs like it should (IE proper tolerance). Then that head just dont cut it.

My experience and observation.

 

[Merlin]

Both me and my brother experienced trail det with 12.5-1 heads. (Sea level).
Couple gallons race gas or just take it off cures the issue.
Absolutely no other signs of det except limp mode. (Yeah i tore it apart)
A very reputable engine builder explained to me how the domes on these heads are cut too thin and will actually oil can and set off the det sensor.
Took my head off and gained 150 rpm with the exact same clutching. Added a gram and its all smiles now on 90 octane. (All we can get in AK)

He is running the mtntk fix kit
I'm running a long rod.

Definately wasn't from not enough load on the engine.
It would det limp from a steady slow cruise, but never if you held it wide open.

Thanks,


What RPM range were both of you experiencing the detonation at???

 

[Sheetmetalfab]

.....

6000-6500 rpm

 

[icr]

I've run the 12.5 par head on two pros, only experienced det once and I attributed it to bad gas. That sled had MTX weights, my current pro has stock clutching. Both sleds were run from sea level to 5k'.

 

[rydningen]

I have been running the PAR ultimate combo at sealevel with the 12.5 domes for about 1000miles. Never saw DET once, but I recently changed out the pistons with some rktek ones and I have now been experiencing DET and limp mode every trip for the last 300miles.

I gained alot of compression with these pistons over the stockers, from 8Bar to 10-11 bars static comp on warm engine.

I guess the compression gained with these pistons are causing the problems I am having, the sled runs very well otherwise. Will be adding some 100LL from now on to eliminate DET.

Sheetmetalfab, did you get the DET issues when adding the longrod?

I have a longrod crank on its way from indydan and I was planning to run the 12.5 head with this crank.

 

[bajah2x]

I had the same problem with my par head,we ride 8-12000 and it was a pain.I tried mtx weights,no help.Best solution is to remove bolt from det sensor and zip tie it to a coolant line,have been running this way for two seasons.

 

[IQRIDR]

Some of you experiencing DET problems with non-stock pistons should check your squish...there might be a small variance there and if you are under .0575-.060 I could see you easily having DET problems without more octane. Lots of guys running these heads and combos and not having any DET problems. Sheetmetalfab is my buddy but I don't agree with him or Indydan about there being any design problem with these heads. Maybe an overactive DET sensor function, exacerbated by thinner or different material used for the head, but I doubt there actually being a true detonation problem. I've sold 70-100 of these heads in the past 3 seasons on Pro's and any DET issues were isolated to other issues or parts present on sleds in my experience.

Any aftermarket piston you use is going to increase the running compression on these motors unless your cylinder has been re-nic'd to proper spec which will also do the same. Sloppy factory pistons don't seal very well. That's why you can check a stock Pro motor and come up with 120 psi, check one with a fix kit and stock head, 135-140 psi, probably the same with Wossner pistons as well. SPI is probably the only piston that won't yield this result considering it is a direct copy of the 2010+ oem "A.B." revision piston.

There are thicker base gaskets available from a few sources, I use them often when building various combos like the fix, long rods, with varying makers of heads, using the various 800 CFI cylinders of which there are now 5 different versions, all very slightly different.

There are a lot of combos available for these motors now and I urge everyone to use proper technique when assembling...checking ring cap, PTW clearance, squish. Can't expect to just throw parts together without doing a little homework and tweaking to achieve the best, most consistent results.

 

[wellfed777]

i think with my pro the 13.6 is just too much comp. i wish i had ordered the
13.1 because i didn't want to deal with race gas
i ride above 5000 and was told i'd be good but on my sled it ain't working
not the end of the world just frustrating
no compaints with PAR really but in the future i'll go 13.1 instead
my sled det 29 times in 500 miles

two gallons of race= none

 

[Sheetmetalfab]

Yep.

Have to agree with iqridr on most of that.
I wasnt about to void my warrenty with indydan and adjust my squish.
He knew i was going to run brads head on his long rod bottom end.
I know my motor runs a little stronger with the stock head back on it so i'm happy with it.
I suppose i could add fuel in the midrange and maybe still run the head, but why if its running well now.

Time to go ride.

 

[Merlin]

Some of you experiencing DET problems with non-stock pistons should check your squish...there might be a small variance there and if you are under .0575-.060 I could see you easily having DET problems without more octane. Lots of guys running these heads and combos and not having any DET problems. Sheetmetalfab is my buddy but I don't agree with him or Indydan about there being any design problem with these heads. Maybe an overactive DET sensor function, exacerbated by thinner or different material used for the head, but I doubt there actually being a true detonation problem. I've sold 70-100 of these heads in the past 3 seasons on Pro's and any DET issues were isolated to other issues or parts present on sleds in my experience.

Any aftermarket piston you use is going to increase the running compression on these motors unless your cylinder has been re-nic'd to proper spec which will also do the same. Sloppy factory pistons don't seal very well. That's why you can check a stock Pro motor and come up with 120 psi, check one with a fix kit and stock head, 135-140 psi, probably the same with Wossner pistons as well. SPI is probably the only piston that won't yield this result considering it is a direct copy of the 2010+ oem "A.B." revision piston.

There are thicker base gaskets available from a few sources, I use them often when building various combos like the fix, long rods, with varying makers of heads, using the various 800 CFI cylinders of which there are now 5 different versions, all very slightly different.

There are a lot of combos available for these motors now and I urge everyone to use proper technique when assembling...checking ring cap, PTW clearance, squish. Can't expect to just throw parts together without doing a little homework and tweaking to achieve the best, most consistent results.

Thanks for the info,

With regard to my application, compression with the original pistons with flaking rings & .0067 PTCW clearance was 118 PSI.............After installing new Direct Replacement Wossner pistons at .0048" PTCW clearance, .018" ring end gap & PAR 13:1 head, compression rose to 135 PSI............

Although I never did actually measure the squish, a visual comparison of the factory & Wossner pistons along with some crude measurements with a caliper show that there is no difference in the shape of the crown of the piston or the dimension between the wrist pin bore & the top of the piston............It was also confirmed by the supplier of the Wossner pistons that those dimensons are the same as a stock piston...............

Out of curiosity, I wonder how many people that are running these kits without any detonantion issues have engines with pistons & rings that are in good shape & respectable PTCW clearance???

I also find the theory of the cylinder head "oil-canning" along with a overactive/oversensitive detonation sensor to be quite interesting............