Turbo Kit for M7

[Phizzer]

Well, the M7 build went good last year. Managed to put some miles on her and break her in good, but I am now on the market for a Turbo Kit to add a little boost.

I have debated about dropping the hammer on a new PC, but this season I am going to try and boost the M7 instead. I've always wanted to install a kit and figured it would be a good year to do so.

What do you guys suggest for Turbo Kits? I see a few different M8 Turbos available on the market right now...Anyone ever tried adapting it to their M7? I am going to keep shopping around and see what I can find, but if you guys know of anything, shoot me a message!! I want to get this ball rolling and see if I can find something this month!

 

[ultrasks700]

What elevation you ride at?
Are you prepared to switch over to Race gas?
If it were me...I'd go with a BigBore kit, something like a RK Tek 800...

 

[Phizzer]

Im riding down at SeaLevel-3500 Feet....I've kicked around the idea of a big bore...But I want a boosted 2 stroke!!!

 

[theUltamateTBM]

I have a boosted m7 with an ovs kit they have been very helpful with any ? I have had. My kit has an aerocharger 53 on it which seems to work OK just run good fuel

 

[fastgas]

A few comments regarding M7 turbos from my experience:
- The M7 can make a lot of power (as much or more than some M8 turbo's on the top end, but not as responsive on the bottom end), but they don't have the det sensor the M8's have so they are much less forgiving and trickier to tune. Definitely plan to run good race gas - at least 110 for anything near 10lbs boost, maybe better for around sea level.

- The M7 doesn't have a DC voltage supply (except for the fuel pump which might be ok for auxiliary injectors) that you will need in order to run auxiliary injectors, oil pump, A/F gauge, etc, so you may need to use a rectifier and capacitor (or battery) for this - but at idle the DC voltage will be too low for the A/F gauge (can be as low as 7-8volts).

- So unless you're good at tuning and can find a kit already designed for the M7 (or plan to do some work yourself to handle the electronics and spend some time tuning since the M7 tuning will be different than the M8), I would recommend starting with an M8, which you can find used for as cheap as some M7's.

 

[theUltamateTBM]

Very true they don't supply enough DC power the kit I have from ovs has no other added strain on that except for the fuel controller and a/f gauge which is nice

 

[Phizzer]

A few comments regarding M7 turbos from my experience:
- The M7 can make a lot of power (as much or more than some M8 turbo's on the top end, but not as responsive on the bottom end), but they don't have the det sensor the M8's have so they are much less forgiving and trickier to tune. Definitely plan to run good race gas - at least 110 for anything near 10lbs boost, maybe better for around sea level.

- The M7 doesn't have a DC voltage supply (except for the fuel pump which might be ok for auxiliary injectors) that you will need in order to run auxiliary injectors, oil pump, A/F gauge, etc, so you may need to use a rectifier and capacitor (or battery) for this - but at idle the DC voltage will be too low for the A/F gauge (can be as low as 7-8volts).

- So unless you're good at tuning and can find a kit already designed for the M7 (or plan to do some work yourself to handle the electronics and spend some time tuning since the M7 tuning will be different than the M8), I would recommend starting with an M8, which you can find used for as cheap as some M7's.

-I was aware of the M7 not having a det. sensor but not in regards to making it more difficult to tune. I already have a KOSO Dual EGT with fast probes to monitor temps. and would have to install an A/F gauge to monitor my ratio. 91 octane is already expensive as hell up here in AK so I would be ordering some 20 gallon drums of Race Gas to accommodate the turbo

-Funny you guys mention the DC power supply...Last night I was contemplating ordering a headlight delete kit and mounting a LED light to run because we do ride at night. I came to the conclusion that I would hold off on this because I didn't have a consistent DC power supply to accommodate a LED light even though they draw next to nothing in power. So, a small Ballastic Battery 12V DC supply would really satisfy all of my needs.

-I can't claim to be "good" at tuning a turbo 2 stroke since I have never owned one, but I do highly enjoy the technical aspect and challenges that would be involved. I have enough background in both the mechanical side and theory (Stoichiometric combustion) that I think it would be a good place to start. However I do hear what you guys are saying on buying an 800 to do the mods too. There are a couple of turbos for sale right now that sparked this interest but they happen to be for 800's so I was curious if anybody had ever attempted to make the conversion. I appreciate all the feedback from you guys!! Looks like I have some thinking to do...

 

[greencat900]

ovs turbo kit for sale

http://www.ksl.com/?nid=218&ad=33716119&cat=472&lpid=&search=m7&ad_cid=3

Here is one for sale

 

[Phizzer]

Thanks for the heads up! I just got off the phone with the guy and it sounds like it might work out!!! He claims to have run 91 pump gas with this kit. He is getting me some pictures of the internals of the turbo. How much does it cost to have the bearings, etc. replaced in one? Is it necessary maintenance to perform every so often? Anything else I should be concerned about?

 

[fastgas]

You can use the rising-rate fuel pressure regulator instead of going with aux. injectors (like OVS kit has), but IMO the stock fuel pump is barely adequate, probably ok for 10psi, which is about all you need. The M8 is easier to tune than the M7, maybe because it just works better on the bottom end (lower rpms) - M7 will be much harder to tune in this area. The M7 will be less forgiving if you start getting detonation - keep a close eye on your plugs, especially if they start to loosen or burn off the tips. For low elevation, I would want the protection of the det sensor, especially if your gas is questionable. You might also think about the exhaust, most kits are pretty loud, a muffler or tunnel dump is more reasonable (make sure it dumps behind the track not in front, which I don't think existed for the m7). Out the sidepanel works well, but at slow trail speeds I would inhale the exhaust which made me nauseous. Also I would never recommend pump gas for the M7 (and M1000), esp. at low elevation. Some M8's are ok with the boost turned way down (6-7psi) and higher elevations (5k+).

 

[mk2g60]

Very true they don't supply enough DC power the kit I have from ovs has no other added strain on that except for the fuel controller and a/f gauge which is nice

need to upgrade to the newer m6 stator then no power issues. i run fuel control box, high pressure auxiliary fuel pump , egt's, h20 gauge, efr gauge on my 600 turbo zero issues with power. it's a must for any small block turbo

 

[M7 Aerocharger Boosted]

M7 vs. M8

I am currently riding a M7 Aerocharger 7psi at 8000+ elevation. It has a rising rate fuel pressure regulator & Aerocharger 53. It is incredibly responsive on the bottom end properly tuned at a 50/50 91&100LL 7 psi. However at 10 psi with straight 100LL and properly tuned and clutched for the additional power, it is less responsive on the low end. M8 will seem easier to tune the bottom end due to the greater base HP. M8 will also produce more HP at a lower boost level due to the larger base HP. 5 to 7 psi go with a Aerocharger M7. Higher the boost the greater the discrepancy between base power and full boost power. High boost start with an M8 and Gtx2863 or Gtx2871 garret turbo. Lag but big power!