670X turbo?

[summitxmtnrider]

Haven't really seen anything on these besides a couple of guys with homemade kits. Is there really anything out there or does it have to be done custom? Just curious, thinkin about building a 670 turbo someday.

 

[DWHalverson]

The rotary valved engines were great for boost due to not having reeds to deal with, but the X/HO engines have the timing advanced quite a bit from the factory and the only way to retard them to standard 670 specs is relocate the key-way for the flywheel. The advanced timing would be an issue I feel. I think you would be better off with a stock standard 670. They also had some problems keeping pto crank seals in. That problem can be fixed though. Not sure on the cast iron bore for cylinder to piston clearance. That might have to be opened up some too.

Dave

 

[summitxmtnrider]

well for now i'm just doing cpi twins and we had the valve cut to 501 specs, replaced all seals and completely rebuilt the motor. head was cut .015. would that help any in your opinion. also when/if i decide to build one are there any kits on the market at all for the 670's or would it be a custom one off build? thanks for the info man, really appreciate it.

 

[triple7]

I havent seen a complete kit. But, my friend used one for years and he did open the piston/cylinder clearance up. It was a non X motor as well. I think he ran like 14 pounds of boost with avgas in it without too many issues. Seems like I remember a Union Bay low compression head on it as well.

Jake

Sorry, your above post came in while I was typing. The head cut on an X motor would be no good. More compression speeds up the flame front, that would make your timing issues worse and it would be harder for you to beat deto.

 

[DWHalverson]

Head cuts are typically bad on boosted applications. Not sure what .015" taken off would raise your compression ratio to. Most guys would build it one off. I could help you out when you get to that point.

Dave

 

[Turbo Performance]

PMed ya

 

[summitxmtnrider]

on the shaved head thing i was just mentioning that, i wouldn't want to bump up compression on a turbo sled that way. i was thinkin more along the lines of whether or not the 501 would help. i've built a few custom turbo streetbikes so i have some experience but not a ton. thanks again for all the help guys.

 

[summitxmtnrider]

oh and dave i'm now a fan on facebook the help is great, and even better you're not all that far from me

 

[DWHalverson]

Cool!! I appreciate it. Face book is another thing that takes a lot of time. I need to look at it more and see what is all there. Keep checking the website for new info and pictures as we have time to add to it.

Thanks again.
Dave

oh and dave i'm now a fan on facebook the help is great, and even better you're not all that far from me

 

[Racegun]

I have most of the stuff off a 670 turbo that I would sell you.
Air box with carbs, power jets, adjustable BOV, hobbs switch, charge tube, rotary valve caps with boost ref., turbo pipe, gearing, guage mount, etc. overall a pretty simple install.
You would need to round up a turbo.
PM me if interested.
Thanks,

 

[motoman620]

I run a 99 670HO with a Aero 53 at sea level, the HO is basically the same as the X motor. I did swap in std 670 pistions, had Union Bay machine some bigger domes for the turbo and pulled some timing out among other things. The only kit available that I was ever aware of was from the original Aerocharger company. I made all my own hardware, air box, charge tube, turbo exhaust.......ect. There is a ton of info out there for boosted 670 stuff if you do some searching.

 

[maxrev3]

I have a complete 53 series 670 turbo kit for sale or the complete sled ready to ride
http://www.snowestonline.com/forum/showthread.php?t=189283

 

[prairiepowderhead]

my brother has a 670 turbo, its a ATS set up by steve benson out of Utah, garrett 2860 with a fuel injection set up with a control box, 15 lbs boost on race fuel, 225 horse , runs good and alot of fun

 

[Motley Doo]

What's he running for a FI system?^^

 

[j_polly83]

There is a guy in new plymouth, id that still does 670 turbo kits, he wanted something like $3500-4000 for the complete kit installed. He also said that the 670 motor is very good and reliable when its turbo'd. The place is called wilderness sports the number is (208) 278-9453, ask him and see what he says.

 

[F-Bomb]

I have a full custom 670 Rotax engine (99HO bottom end and jugs, 97 style pistons, 97 ignition flywheel, rotary valve match, rotary valve watercraft replacement seal (anti coking), pto block plate, ported, union bay head with turbo domes hand decked to perfection, setup for pre-mix) with the largest 53 aerocharger turbo (big mouth open intake and get this AN INTERNAL SCREEN (probably one of the most valuable aspects of this system for aerocharger) system that is solenoid nitrous injected. We were the first racing team on the planet to accomplish safe reliable high performance injecting nitrous with a turbo on a two stroke application. Now it's common place with all types of turbos. The system has a custom polished aluminum airbox (with dial a jets) and cermachrome charge tube. Very rare coated 97 Fatboy pipe. Runs a custom overdrive machined Polaris 85 primary and Arctic Cat secondary. It is setup with quick disconnect for drag race cooling. Electronics are DT54S RE2W Digatron EGT data logger but also analog boost and fuel pressure gauges.

....all this is in a 99 Summit X chassis with a 151 custom rear PLP coil over rear suspension with Mountain Machines big wheel and complete drag race setup aluminum idler wheel package. It has two tracks one is a 2" hard durometer 151 camoplast finger for mtn use and winter snow drag racing and the other is the same track cut down to 1" that we would install and un-install traction screws depending on the class and rules for the race of the day in grass. It also ran on the grass with the untrimmed finger track for SMALL CC OPEN MTN CLASS and was absolutely dominating (no trimming or traction allowed). The front is sprung fox dropped shocks over PLP chromoly t-arms and PowerMadd mini drag skis.

....anyways stumbled onto this thread and it got me thinking about this sled gathering dust. It has sat in our shop for a long long time since we got out of racing. If someone wants to have wicked fast winning combo drag sled or convert back to a mtn climber this might be a rare opportunity to take advantage of thousands of hours of professional experience along with an absolutely disgusting amount of money for a fraction of replacement cost.

Think you might be interested in getting into drag racing or converting back to a hillclimber give me a pm and we'll discuss wether or not this would be a good opportunity for you. Or if you want to truelly get into a turbo for your rotax I can coach you along from our experiences over the years.

How much? Don't know..it's going to require discussion and the right set of circumstances by the buyer. If you are qualified, legit, and serious pm me and we can talk about it. It will be cheap to the right person. If anyone is interested I'll drag it out and get some current pictures.