TD/GAP Big Turbo first impressions

[hpmaniac]

Wow wtf, what belt??? i have a 550hp can am x3 running a zona rotor xr54 turbo at 48psi on e85. I tried every belt i could, getting good belt holding ability was not the issue it was the belt capable of holding the stress. The only belt i have not broken is the gboost rs belt. A factory can am belt will last 2 pulls i the sand. Belt pulls apart. Belt temp 90 degrees F. 130mph in the 1/8th!! wow man what a rocket!!

 

[DMCTurbo]

Wow wtf, what belt??? i have a 550hp can am x3 running a zona rotor xr54 turbo at 48psi on e85. I tried every belt i could, getting good belt holding ability was not the issue it was the belt capable of holding the stress. The only belt i have not broken is the gboost rs belt. A factory can am belt will last 2 pulls i the sand. Belt pulls apart. Belt temp 90 degrees F. 130mph in the 1/8th!! wow man what a rocket!!

I have the same issues and coincidently the only belt I haven't broke is the Gboost RS. I've lined up clutches at full shift, done everything to make sure alignment, etc... is all good. I get a handful of passes out of an XS belt. Clutches will be cool, no sign of slip, then next pass breaks right in half. It's really frustrating. I'm starting to wonder if the motor under torque is moving causing clutches to become out of alignment. I do have 10000 miles on my chassis. Maybe I'm just at the limits of the Yamaha clutches.

 

[hpmaniac]

I have the same issues and coincidently the only belt I haven't broke is the Gboost RS. I've lined up clutches at full shift, done everything to make sure alignment, etc... is all good. I get a handful of passes out of an XS belt. Clutches will be cool, no sign of slip, then next pass breaks right in half. It's really frustrating. I'm starting to wonder if the motor under torque is moving causing clutches to become out of alignment. I do have 10000 miles on my chassis. Maybe I'm just at the limits of the Yamaha clutches.

Wow crazy that we found the same limit.
The rs belt has a grippy compound as well.
Expensive but strong.
I think we are just finding the limit of these belts.

 

[Simplespeed]

I have the same issues and coincidently the only belt I haven't broke is the Gboost RS. I've lined up clutches at full shift, done everything to make sure alignment, etc... is all good. I get a handful of passes out of an XS belt. Clutches will be cool, no sign of slip, then next pass breaks right in half. It's really frustrating. I'm starting to wonder if the motor under torque is moving causing clutches to become out of alignment. I do have 10000 miles on my chassis. Maybe I'm just at the limits of the Yamaha clutches.

The power your putting to those belts is creating movement and you are right on target with your assessment of why your blowing belts. Mount a camera on sled where you can see this movement under power with rider and you will be looking for some torque arm to keep clutches in perfect alignment.. Great job and a ton of work to get over 150 on any sled… Very Impressive…

 

[See n blue]

Very impressed with how fast you’re going with what you have done. Do you ever run it on snow? Curious what the difference is speed wise
Killer set up btw

 

[DMCTurbo]

Very impressed with how fast you’re going with what you have done. Do you ever run it on snow? Curious what the difference is speed wise
Killer set up btw

Thanks. Never ran it on snow.

 

[Doc Harley]

Statement from TD...

Has anyone seen evidence (on pump gas) of needing head gskt/studs sooner? If so, what HP level does this become a concern?

 

[Turboflash]

Yes. Not sure about when an upgraded head gasket is needed but I have seen evidence of movement of the head on even 270 tuned 998s. When I took head off one, there were not distinct clear sealing lines from head gasket. I could tell the head had been moving around on block surface. I was repairing that 998 for starting issues/steam after starting along with coolant smell. Engine would not hold pressure test on cooling system. Cause was not enough clamp force on head causing a breach of sealing surface.
So, after checking flatness on both block and head, I installed ARP head studs, new Yamaha head gasket. That was about 3 years ago, and owner says all is well. IMO, the stock head bolts are marginal at anything above stock boost.

 

[Doc Harley]

Yes. Not sure about when an upgraded head gasket is needed but I have seen evidence of movement of the head on even 270 tuned 998s. When I took head off one, there were not distinct clear sealing lines from head gasket. I could tell the head had been moving around on block surface. I was repairing that 998 for starting issues/steam after starting along with coolant smell. Engine would not hold pressure test on cooling system. Cause was not enough clamp force on head causing a breach of sealing surface.
So, after checking flatness on both block and head, I installed ARP head studs, new Yamaha head gasket. That was about 3 years ago, and owner says all is well. IMO, the stock head bolts are marginal at anything above stock boost.

Could be very depressing news, T.F. appreciate the input. Wondering if that's the rule, or an anomaly? I think the majority of those whom tune, run 270+.
Perhaps, we'll get some more feedback.
T.F. it's one of those things that probably gets overlooked by many.

 

[0degC]

Could be very depressing news, T.F. appreciate the input. Wondering if that's the rule, or an anomaly? I think the majority of those whom tune, run 270+.
Perhaps, we'll get some more feedback.
T.F. it's one of those things that probably gets overlooked by many.

Head studs really good idea at 17lbs and a must above this I would say? I think stock head gasket is fine if not damaged before putting head studs in. Of course if going to fully locked waist gate this is a different game, heavy duty head studs and o ringed head works well i hear.

 

[Doc Harley]

Head studs really good idea at 17lbs and a must above this I would say? I think stock head gasket is fine if not damaged before putting head studs in. Of course if going to fully locked waist gate this is a different game, heavy duty head studs and o ringed head works well i hear.

Well, that's too bad. No one ever says anything about this, "head studs & whatnot." Thanks for playing out the different scenarios. BTW, Who did you hear about, locked WG's & o rings?!?! Lol. Nevermind....

 

[REDLINE 1]

Well, that's too bad. No one ever says anything about this, "head studs & whatnot." Thanks for playing out the different scenarios. BTW, Who did you hear about, locked WG's & o rings?!?! Lol.

Yes. Not sure about when an upgraded head gasket is needed but I have seen evidence of movement of the head on even 270 tuned 998s. When I took head off one, there were not distinct clear sealing lines from head gasket. I could tell the head had been moving around on block surface. I was repairing that 998 for starting issues/steam after starting along with coolant smell. Engine would not hold pressure test on cooling system. Cause was not enough clamp force on head causing a breach of sealing surface.
So, after checking flatness on both block and head, I installed ARP head studs, new Yamaha head gasket. That was about 3 years ago, and owner says all is well. IMO, the stock head bolts are marginal at anything above stock boost.

Nevermind

Wouldn’t mind doing head studs / gasket on mine for peace of mind. Kind of intimidating job for me never dug into it that far don’t wanna screw anything up. With proper direction I think I could do it though just finding accurate step by step instructions is hard

 

[74Nitro]

I'm just finishing one up.
Sled was rode without coolant.
Dealer fixed hole in heat exchanger, but sled was pushing coolant. They then changed the head gasket but sled only went a couple hundred kms and began pushing coolant again.
I didn't really want the job, but guy was almost begging me to do it. Taking it apart notice two bolts loose. Threads are pulled out of block.
So I got long helicoils and did all 8 holes. Had head surfaced, out 5 thous.
Opted to use ARP head stud set.
Looking to run it this week.

 

[Doc Harley]

Wouldn’t mind doing head studs / gasket on mine for peace of mind. Kind of intimidating job for me never dug into it that far don’t wanna screw anything up. With proper direction I think I could do it though just finding accurate step by step instructions is hard

DMC mentioned an SXS blog (video) on YouTube. I watched it. Looks like if you've got everything in time when you take it apart, I'm guessing you'd just put it back together.
Redline1, it's not something I'm excited about. And it seems it's one of those things where you're damned if you do, and damned if you don't.

I'm just finishing one up.
Sled was rode without coolant.
Dealer fixed hole in heat exchanger, but sled was pushing coolant. They then changed the head gasket but sled only went a couple hundred kms and began pushing coolant again.
I didn't really want the job, but guy was almost begging me to do it. Taking it apart notice two bolts loose. Threads are pulled out of block.
So I got long helicoils and did all 8 holes. Had head surfaced, out 5 thous.
Opted to use ARP head stud set.
Looking to run it this week.

This is why I struggle to give my sled to someone else. If I wanted things F'd up, I can do that myself.
quite sad if you think about it. You can't bring the sled back to them. Live & learn

 

[Turboflash]

I've fixed 998s that run "only" about 14-15 psi boost where I could tell head wasn't sealed completely. IMO, knowing what I know now, I'd say head studs on anything above 12-13 lbs boost. Stock torque-to-yield head bolts just don't provide enough clamp force for me. But, ARP head studs do.