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I tried this on a completely stock machine today. It picked up 1 hp at the track and exactly 100 rpm.
So what was the track HP for the stock sled?I tried this on a completely stock machine today. It picked up 1 hp at the track and exactly 100 rpm.
Turboflash
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Oh, is that all, LOL. Needs more boost to work better. Ask me how I know, LOL!!!I tried this on a completely stock machine today. It picked up 1 hp at the track and exactly 100 rpm.
Thank you sir.
TF, What was the ambient temperature where the track Dyno was? Thinking your AIT was potentially higher than normal operating temps when you're out on the lake. I'd be curious to see actual numbers for power loss at certain levels.
Turboflash
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I believe 55 F. These sleds do have IAT sensor so theoretically the ECU should adjust fuel accordingly. That said, I don't know how well it does that. We know that when riding these sleds in cold weather (like single digits and below zero) they do seem crisper performance wise. Makes me wonder if the IAT correction system has limited capability? IDK.
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So what was the track HP for the stock sled?
Stock sleds make 96-102 hp heat soaked on my track dyno depending on track length, lug height, quantity of studs and mileage on sled itself. That number equates over to 192-204 crankshaft horsepower roughly.
TF, What was the ambient temperature where the track Dyno was? Thinking your AIT was potentially higher than normal operating temps when you're out on the lake. I'd be curious to see actual numbers for power loss at certain levels.
Shop air is 55 degrees. Most runs last about 4 seconds and I like to do back to back to back to back (4 runs in a row) so everything is heat soaked. I usually start each run at 150-155 degree coolant temp and the last run is 175-180 typically.
1nc 2000
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When my iat was acting up the machine ran just like the jetting was way off on a carbed sled.
When shorted iat it would read -40°f and sled was pig rich.
When shorted iat it would read -40°f and sled was pig rich.
KnappAttack
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TF, What was the ambient temperature where the track Dyno was? Thinking your AIT was potentially higher than normal operating temps when you're out on the lake. I'd be curious to see actual numbers for power loss at certain levels.
Steve, what I'm hearing you ask is, what would be the results if it was cooler out in the field, and with a colder intake temp with better cooling thru the intercooler in cold weather, would it be better or worse for gains. Did I get that right?
The colder the air the more dense the charge so it'll require more fuel. Tim did you have closed loop during that scenario and log the fuel?
Yeah Mike, we know we're going to lose power with warmer air. It would be nice iDyno could quantify this as the AIT climbs each run on the dynoSteve, what I'm hearing you ask is, what would be the results if it was cooler out in the field, and with a colder intake temp with better cooling thru the intercooler in cold weather, would it be better or worse for gains. Did I get that right?
KnappAttack
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Stock sleds make 96-102 hp heat soaked on my track dyno depending on track length, lug height, quantity of studs and mileage on sled itself. That number equates over to 192-204 crankshaft horsepower roughly.
Shop air is 55 degrees. Most runs last about 4 seconds and I like to do back to back to back to back (4 runs in a row) so everything is heat soaked. I usually start each run at 150-155 degree coolant temp and the last run is 175-180 typically.
Allen,
I know way back when I'd dyno these machines on the track dyno, (actually only used a track dyno twice really) but we'd use .57 as a factor from engine to track dyno figures. I remember having my brand new zero mile turbo Apex on Jeff Simons engine dyno, it was right about 264-265 HP, we'd hooked it right to the track dyno within minutes that same day and it showed first stab at the clutching of 144 Track HP and improved it to 149-150 Track HP with clutch refinements at that engine HP level. Why are people now using .5 as a factor on the track dyno? I always laughed at TD for using this figure.
According to that .5 factor, my old Apex turbo should have been 300 HP and it really wasn't that much at the engine, although I've always said that was the fastest turbo sled I have owned & trail rode too, till this tuned Winder, I feel they would be pretty close power wise in actuality, the Apex was 265 HP and the Winder is "supposed to be 300". I feel they must be very close to actual track HP thru my butt dyno. I know all that matters it what it really makes to the track. Just wondering if something has changed in the factors being used. I'm guessing its because people are not actually making the engine power they really say they are making. Engine numbers seem to be pretty inflated vs actual in this snowmobile world. Imagine that....
I also had my old V-Max 800 on the Wheelock's track dyno one day. Same thing, the factor I arrived at was .57 as I knew the real engine HP of that one too.
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