Just bought a used 07 m8 153, but I'm throwing on a 162. It has the slp pipe and slp air intake. Holds 7950 climbing the steep and deep with the help of mtx weights. It just seems like its lacking some power here somewhere. Doesnt seem much better then my m7, actually very close. I'm sure my old 02 rmk 800 had more snap and power. Maybe its the 5 years on a yami turbo, but I'm sure this babies got more potential then this! Someone must have some magic recipe clutching/gearing info for me. Right now I'm sure I will be getting spanked by the xp's. With this pipe I thought it would narrow the gap, but not the way it is now. Pm me if its top secret.
I will offer my opinion based on my experience having had 1 or 2 New M8's every year since they came out..
1) The 07 M8 makes slightly less power (about 3 HP) than the 08 or 09 M8.. BUT the performance difference on the hill is HUGE when comparing the 07 with the 08 or the 09.. WHY?? IMHO, it is in the diamond drive.. I suspect the there is major HP robbing in this piece in 07 ONLY.. Why do I say this?? Well. because we have these sleds every year.. For example.. We could mod the 07 M8 (in 2007) with head and porting and absolutely destroy stock 07 M8's in all manners.. Now enter 2008.. This same modded 07 M8 will barely out perform a STOCK M8..Keep in mind this 07 Mod M8 (and we did MANY) will destroy other 07 M8's but will pale in comparision to the STOCK 08 M8.. OK, I started an investigation... Cat says, they changed the ECU programming... So, since we had an 07 M8 and a 08 M8 at the same time... we swapped ECU's NO difference in performance with either sled.. the 08 with the 07 box still ran like it did before and the 07 with the 08 Box still ran the same. NOT THE ECU... So, change the pipe and Y pipe between the 2.. NO difference.. NOT THE PIPE EITHER!!
At this point.. we ran out of time and desire to truely determine what the culprit really was.. But the 07 M8 will not pull hard.. It ALWAYS feels likeit has the brakes on.. So, I suspect gear mesh in the DD, or some sort of drag in the DD or the shafts..
2) Install the mod 07 M8 cylinders on the 08 M8 and the 08 M8 gains major power... just like the 07 M8.. So, now the 07 M8 is really left in the snow dust...
3) Clutching helps but the 07 will still never pull like an 800 should... But clutching an 07 M8 will make up the gap with the 08 or 09 M8.
Bottom line is: CAT willnot tell us where the "hold back" lies on the 07 M8. They claim it to be the ECU and pipe but we have proven otherwise.. You can definitely feel the "resistence" on the 07 M8 that is causing it to not perform to its potential.. This resistence is not present onthe 08 M8 nor the 09 M8.. Go figure..
Side note: the 07 M10 is better than the 08 M10 IMHO.. so one has to believe that the 07 M8 isuse is not in the rear skid..
So,that is my experience with it.. I suggest not spending too much time or $$$ on the 07 M8 because it will always be inferior to the other 800's (and 700's) Now if you are in a group of only 07 M8's like I said, you can get it to run MUCH better than the other 07 M8's but never as good asa the 08 or 09 M8's
I am not trying to "dog" the 07 M8's in any way shape or form.. BUT, the fact remains.. that they had a FACTORY issue that robs performance and Cat has managed to keep that "issue" hidden to this day.. You can thorw mod after mod to the 07 M8 and it will get better but it will still not perform like the 08 or 09's. So, adding a pipe or pipes to this sled will add performance.. BUT add the same pipe or pipes to the 08 or 09 M8 and the gap increases... It is very frustrating...
Kelsey
