Tuning help AC Speedwerx 800 Race Mod kit top end on M7

[cwborns]

Like the title says I just bought an Arctic Cat 800 Mod top end built by Speedwerx with Speedwerx billet head and ceramic twin pipes.I believe the pipes are part of the kit. I will be running STM valves, Boondocker, TEAM A/F dual sensor data logging unit, Vforce 3 reeds & spacers, Digitron 4 window EGT w/exposed tip probes, big air intake. I will also be making a lot of chassis and body changes. TIME TO START GETTING READY FOR NEXT YEAR! Praise the sled gods for watercross. Summer doesn't have to suck so much

1. How will this engine perform when I buy domes to run it on 93 pump gas? Will it not run as strong as it should? What will I be loosing?

Note: I ride the Keweenaw in the U.P. primarily boondocking, side hilling, and hill climbing. Trails are really nice for getting from the house or trailer to a place worth riding. So I will be running low alt. domes.

2. Any clutching tips are would be appreciated for both primary and secondary! What spring weight should I have? I plant to run Ti Team springs. On the secondary I have done so up dating to my 05' adjustable spring tension BD clutch rock rollers, Dalton 48/38 helix, the new deflection adjuster and I have all the tools, and a roller bearing system to keep the spring from binding. Re-gearing Diamond drive?

Note: It has a stock diamond drive system and is a 05 M7 anything over 100 mph is not all that important too me. I like get up and go. Being the first one to 85 would be nice.

3. This top end came with these ceramic twins that are not the style that wrap up and over the engine and are not designed to exit anywhere near the stock location being race vs. powder design. Do I have to run these pipes even if I can’t get a different silencer to fit my sled for performance reasons? Or are there other pipes that will work just as well?

4. Any important tuning tips would be appreciated. Do I need to make crank changes at around 175hp? Does anyone know what this thing actually makes for hp if it is as it should be? Should I be doing any bottom end work like porting? Check electrical timing, Check cylinder port timing w/dial indicator and timing wheel? Crank balancing…can I do that? Is it like a boat prop? The bottom end has 600 miles on it and I will be putting a crank saver on it.

5. Are stock throttle bodies sufficient or is boring something that really should be done?

6. Blue printing advice, what I need to do exactly (finer points), Things to pay extra attention to, what I should look for, etc…

Well that’s all the engine questions I could think of. I do not think I am as clueless as this post makes me sound. I just don’t want to assume that I know anything when I can ask the gurus for help and advice. Do it right the first time or don’t bother! The gurus are disappearing and the art is being lost! This is your chance to make sure there will be at least one more guru in the future. Help an engineering student today! Yes there is a future engineer asking for help. I hope you guys like that, you probably don't hear it enough.

Thanks guys for your time and input!
Chris

 

[lostNthesauce]

i have one i dropped in a 05 m5 chassis, kit runs awsome. i left the high comp domes in mix it 50/50 and ride above 6000 ft. it has a 162 mavrick with stock m gearing. for clutching i run slp blue/pink drive(140/340) with cat 72 gram weights ground down to 71. team spring red/pink, with d&d shift assist, and dalton 42-34 helix. and spin the motor at 8250(the torque peak). pulling a hill sled makes awsome track speed usually between 56 and 61 mph. should be a deadly combination for you, i know i haven't found a m1000 or big bored xp that will run with it.

 

[cwborns]

i have one i dropped in a 05 m5 chassis, kit runs awsome. i left the high comp domes in mix it 50/50 and ride above 6000 ft. it has a 162 mavrick with stock m gearing. for clutching i run slp blue/pink drive(140/340) with cat 72 gram weights ground down to 71. team spring red/pink, with d&d shift assist, and dalton 42-34 helix. and spin the motor at 8250(the torque peak). pulling a hill sled makes awsome track speed usually between 56 and 61 mph. should be a deadly combination for you, i know i haven't found a m1000 or big bored xp that will run with it.

Hey thanks a lot for the points. The torque spec expecially! I am way too excited about this thing. I don't think I will be able to wait until next winter to ride it.

 

[G-Force]

Been humming and hawwing about getting one of their kits, but gonna keep it to a single pipe, just hopin to keep the tuning hassle down....
lost, what ratio are your domes? Jeremy suggested 13-1 for me (4000' and up)
G.

 

[cwborns]

Well I will spend a majority of my time between 900-1500ft so I was planning to run 12.7:1 domes or 12.5:1. I have been told availability may be an expensive issue.

 

[Ove]

I would go even lower on compression. I run 12.5 with slp twins sealevel and it is too much. 32mm stingers keeps up for 1250ft tops.

I red somewhere that Speedwerx uses the 12.5 with the 2 degree key in backwards.

 

[sledhead Ed]

Make sure it's not an early version. The pump gas head they sell won't work. The one I'm did for a riding buddy, the pistons stick up above the cyl. ..030ths. It was 03 version. Do a trial setup on one cyl and piston if you're not sure of year of the race kit and measure yor deck height. This ended up being a couple month headache being told it wasn't their cyl+parts to finding out it was basicly an early kit that was done different. pistons are the same. Also make sure they don't want you to run 2 base gasket before you put it all together

 

[cwborns]

thanks a ton for the heads up man!