998 engine rebuild

[justinator]

Way to many variables to blame tune

Not really, a functioning knock detection system alerts the driver that your engine isnt happy with its current situation. If your engine fails and its nothing to do with knock or excessive heat than ya, many variables can cause this. When you have signs of deto and drooping pistons well its quite clear nothing alerted the driver or the driver ignored it. Im quite confident in this case the driver DIDNT ignore anything as observant as he is.

 

[stgdz]

So does the head not have sufficient cooling or do the coolers not have sufficient cooling?


I would imagine if it's the later wile will see a few rear mount rads in the future from a few maniacal people.

 

[74Nitro]

So does the head not have sufficient cooling or do the coolers not have sufficient cooling?


I would imagine if it's the later wile will see a few rear mount rads in the future from a few maniacal people.

Deto can occur even with engine adequately cooled.
However, it would be nice to add more cooling capacity to these sleds.
I don't see how it would b easy at the back.

 

[STAIN]

B.O.P had a radiator kit made for the sidewinder.

 

[sideshowBob]

B.O.P had a radiator kit made for the sidewinder.

I bought this kit from Travis[BOP] when they were first released but have yet to install it...hopefully put it on for next season.
This year we had less snow and icier conditions then typical and I found I had to use my scratchers to keep temps down at times.

 

[max rolph]

Wouldnt it be nice if some well respected chemical company like amsoil, lucas,redline,VP...etc would make test strips.... somthing like used for your hot tub, we could carry these in the sled and test questionable fuel stops for advertised octane value... then nail the bastards on the spot for costing us $thousands in repairs because of selling deficient fuel at the pumps.

 

[0degC]

So does the head not have sufficient cooling or do the coolers not have sufficient cooling?


I would imagine if it's the later wile will see a few rear mount rads in the future from a few maniacal people.

Both. The overall cooing system is marginal you pretty much need scratchers or increase capacity. At higher boost the heads seem to not cool fast enough, they weren’t made for 300hp.

 

[SledFreak]

The BIG unknown for us guys is what's coming out of that gas pump handle when we pull in for gas. Is it 91 like it says? The tuners tune with gas that has a octane rating and the tune is created around THAT GAS.. If gas coming out of the pump IS the same as the tuners GAS then hold it tight should be doable for 5 miles..

When I put 91 or 93 in my sled at the pump, I always add a couple of bucks into my truck first to empty the 87 from the hose. TD actually says to to this...

 

[1nc 2000]

What are you guys running for an intercooler to bring the air temps down?

 

[NYTurbo]

Very simple solution really don't hold it wide open for miles. Lol
Not many vehicles have a cooling system to with stand WOT for any length of time.

 

[DooZ]

If the tune is correctly mapped on the dyno with proper A/F, timing and fuel octane is followed accordingly, holding it for 5 miles wide open shouldn't be an issue.

The dyno is just one of the tools that should be used for developing the tunes. I know I don't want my high hp on the edge tune just cooked up in a controlled environment. Like previously mentioned, fuel quality plays a big part to all this. IMHO holding a significantly modified sled wfo for miles is just a waiting game before some component is over taxed.

 

[74Nitro]

The dyno is just one of the tools that should be used for developing the tunes. I know I don't want my high hp on the edge tune just cooked up in a controlled environment. Like previously mentioned, fuel quality plays a big part to all this. IMHO holding a significantly modified sled wfo for miles is just a waiting game before some component is over taxed.

Guess it depends on ones definition of significantly modified. On the 'edge' is not what I would call correctly mapped.
Of course there will be a point when there is no more HP to be had for a given octane. When the map supplier says for example that power trail is safe for 91 octane, or the next higher tune with an exhaust on 93, then I trust that it will be and that I can hold it wide open for miles.
Admittedly, there are not many places to hold these wide open for miles and miles, aside from lakes and stretches like in my avatar pic.

 

[Turboflash]

It took me a while to realize (and experience) the 998 cooling system, engine designz casting thicknesses, heat exchangers were all designed for 200HP not 300.
Agree w 74Nitro there aren't many places where you can hold a 280+ HP sled WFO for a couple miles but I did cuz I know the flowage I was on. Admittedly it was both thrilling and unnerving to run that distance w speedo showing around 135. Yikes.
Never really thought about track but provably should if.
After cooling it down by easy riding aroind in good snow for 5 minutes, and idling it for several more minutes when I shut it off I could still hear coolant gurgling in head. Coolant temp during run maxed out around 180.
This tells me the head cannot handle that level of heat for that long. Head and pistons cannot stay cool at 17.5 psi boost for several miles. Heat load overtakes design and starts to melt stuff.

 

[1nc 2000]

I run a 28 inch snownflap. The longer flap helps with keeping more snow cooling the heat exchanger. Not saying its a cure all but it helps.

 

[stgdz]

It took me a while to realize (and experience) the 998 cooling system, engine designz casting thicknesses, heat exchangers were all designed for 200HP not 300.
Agree w 74Nitro there aren't many places where you can hold a 280+ HP sled WFO for a couple miles but I did cuz I know the flowage I was on. Admittedly it was both thrilling and unnerving to run that distance w speedo showing around 135. Yikes.
Never really thought about track but provably should if.
After cooling it down by easy riding aroind in good snow for 5 minutes, and idling it for several more minutes when I shut it off I could still hear coolant gurgling in head. Coolant temp during run maxed out around 180.
This tells me the head cannot handle that level of heat for that long. Head and pistons cannot stay cool at 17.5 psi boost for several miles. Heat load overtakes design and starts to melt stuff.

Would be interesting to see how the 240 tunes handle the wide open for miles that you do.