There was a twin turbo at glenwoods radar runs and he only hit 89 in the 500. Yeah, 89 is really fast, but not for a supposed 330 hp sled. Everyone was sayin it would go like 140 in the quarter, 190 top speed.

I raced him out in the field, along with another RX-1 and a Storm 800. We all took off but the twin turbo rx-1, when I was about 200 feet into the race on my zr600, he took off and passed me before the end. It was only a 800 foot race or so.

The thing sounded like it had a jet engine too, and only 89 in the 500 :confused:

Anyone seen somethin like that?

i'd say once you got that rx-1 turbo tacked up you will want more weight then it already has. :ohmy:

500 ft really isn't far enough to notice the benefits of a turbo. Turbo's run off boost and don't really help too much in the low end. Don't kid yerself that twin turbo would scare John Force at top end. I also gotta figure this guy was having a hell of a time hooking up.
Wayne

Originally posted by CyberkineticMonkey@Feb 1 2004, 03:17 PM
and only 89 in the 500 :confused:

It doesn't matter whether it went 89 mph or 189 mph.
How did it compare to the other mod sleds? Post some other speeds.

There was like a pure alcohol drag sled that went 98, and some uber modified polaris that went 91, but that was it.

This thing wasnt stripped down at all or anything. It probably weighed 600 somethin pounds, he uses it as a trail sled.

Rev 800's were runnin low 80's and F7's were runnin high 70's

Thats all I remember, there werent manmy fast sleds.

Doesn't sound like it did too bad them...... for still being trailable.
I don't know why anyone would 'twin' turbo one (other than for bragging rights).
A Bender or M-C setup probably wouldn't have been much slower.

Thats funny, 330 horse snowmobile.

When we were racing and he went by I freaked out, I was yelling inside my helmet and stuff. It was like nothing I'd ever seen.

Originally posted by WKinneIII@Feb 1 2004, 04:28 PM
Turbo's run off boost and don't really help too much in the low end.
No they make boost. But you are right. A turbo does nothing to help a sled in the bottem end. The harder you make an engine work the more boost the turbo will make. But 500 feet is nothing. The Turbo's would be just getting spooled up.

I have heard of people adding nitrous to help the low end and using the turbo for the mid to top.

TRACTION..TRACTION..TRACTION....or lack there of...

You need a longer run for a turbo to spool up!!
Now, if it was a supercharger... different story!

Most likely so much torque it wouldn't hook up, a longer run may have yielded far different results.

Rick.

I was @ Glenwood and saw that sled run. You could tell that the turbo on that sled needed to be adjusted, because it sounded like it was killing the sleds low-end. Anyways, not bad, he was spinning the track for almost the entire 500ft, but I too thought that sled would be faster.

Did you run your sled?

Originally posted by CyberkineticMonkey@Feb 1 2004, 09:06 PM
Thats funny, 330 horse snowmobile.


you dont think there is one? i saw one in an article that was 335hp, and that wasnt even turboed. it wasnt an rx1 either though :p

How could you say the turbo was killing the low end and then in the same breath say he was spinning the track for the whole 500 ft!?! Obviously power wasn't an issue or he wouldn't have been spinning the track so much. He could have had twice the hp and it wouldn't have done him any good if he couldn't hook up.

As for turbos needing to spool up, yes they do need to spool up but it would only take minimal time. Maybe 1 sec or so, and I assume the race took longer than 1 sec. As far as turbos being no good for low end, I'm not too sure that is true. Any time you force feed an engine(turbo or supercharge), torque increases significantly. In cars, superchargers are quicker to respond because they are belt driven and always spinning, waiting to be tapped for boost. A turbo needs to spool up and requires exhaust pressure to spin the turbine. Usually a downshift is the most effective way to speed up the process. With a CVT (continuously variable transmission)in a snowmobile the engine is never too far from its optimum rpm so the turbo would spool up quite quickly. A turbo is very efficient. It is basically free horsepower from an engine load standpoint. A supercharger is robbing power from the engine all the time, kind of like air conditioning. A turbo is just using exhaust gas that is exiting the engine any way. Just my 2 cents.

I talked to a kid whos dad workson the sled today. Its like 250hp on low boost and 345 on high if I remember right. Yeah he was spinnin the whole way, but it was really unimpressive. But when I raced him it was unreal, he got up to like 130 in a pretty short field in kinda fresh snow(farther back where everyone was dragin to the people who were there).

No I didnt run, Im not 18 and I really dont look it so I couldnt sign up anyway. I had a green ZR600 with a green chrome windshield, but there were so many ZR's there you wouldnt remember it. I was parked down by the concession stand by a ZR800 and a buncha polaris's.

Oh and that other RX-1 that ran like a 91 was out there when I raced him to. It was actually supposed to be both RX-1's goin at it.

The guy with the twin turbo said it wasnt warmed up and it wasnt reads, but the other guy went anyway, and so did I. I was probably 200 feet done and the other RX-1 was as well. Then the twin turbo one blew past me and the other RX-1. I said it before but it was unreal and sounded like nothing Ive ever heard (all I can think is jet car), the turbos were so loud.

Did you hear that thing at idle? Absolute sweetness. I know the guy that owns it (evan)

Oh, and they said they detuned it so the owner could go trail riding, it normally needs to run 110 octane and stuff, it wasnt in its racing form.

Oh, and I heard that the owner ran 160 in the quarter mile on asphalt.

Ive heard many things...

Originally posted by Hoamer@Feb 2 2004, 08:47 PM

As for turbos needing to spool up, yes they do need to spool up but it would only take minimal time. Maybe 1 sec or so, and I assume the race took longer than 1 sec. As far as turbos being no good for low end, I'm not too sure that is true. Any time you force feed an engine(turbo or supercharge), torque increases significantly. In cars, superchargers are quicker to respond because they are belt driven and always spinning, waiting to be tapped for boost. A turbo needs to spool up and requires exhaust pressure to spin the turbine. Usually a downshift is the most effective way to speed up the process. With a CVT (continuously variable transmission)in a snowmobile the engine is never too far from its optimum rpm so the turbo would spool up quite quickly. A turbo is very efficient. It is basically free horsepower from an engine load standpoint. A supercharger is robbing power from the engine all the time, kind of like air conditioning. A turbo is just using exhaust gas that is exiting the engine any way. Just my 2 cents.
You are partially correct but not 100%. It is not only exhaust pressure that makes the turbo do what it has to do. The turbine side is powered by hot expanding exhaust gas, a lot of hot expanding exhaust gas, the more and the hotter the expanding exhaust gas the better the turbo will work. Pressure from an engine with no load allows the turbo to make little if any boost. The exhaust turbine will not generate enough power to turn the air compressor fast enough for it to work properly unless the engine is feeding the exhaust turbine a lot of hot expanding exhaust gas, a condition that can only be created when the engine is under a load. The fact that the engine must be under a load is the reason why, no matter how high you rev a turbo charged engine with no load on it, you will not see the boost gauge move. As for the no bottem end with turbo's this assumption usually comes from a well known problem called " turbo lag ".This is basically the amount of time it takes from the time you place a load on the engine (mash the throttle flipper and the clutch's engage) until the time the engine is capable of developing enough hot expanding exhaust gas to spin the turbine fast enough for the compressor to do its job. Until this "lag" is overcome the engine is basically normally aspirated and the compressor is acting like an exhuast restriction. To minimize this "lag" the turbo or turbo's must be properly matched to the capabilities of the engine that they are mounted to. Clutching has to be spot on as well as gearing and traction. To minimize "lag" one can make the turbine and compressor smaller. This will allow the engine to create boost faster but usually limits the amount of boost that the turbo can create. Make the turbine and compressor larger and "lag" is extended. Add a waste gate and you can create a turbo that spools up faster and creates lots of boost but the waste gate allows excess pressure to bleed off so as not to damage the engine. Of course torque will be increased but one must first overcome this lag. This is kinds simplified but you should get the idea here. Before we can critizize a turbo it's best that we understand what it first does .

Good explaination Rob, thanks.
Just goes to show you how important set-up would be with a turbo, to get the most out of it. I worked on Saabs for years, and when that thing spooled up watch out, what a gas!!

*Update*

The owner now runs Top Fuel Dragsters in the IHRA.

Evan Knoll, you rich...grrr

An RX1 isn;t FAST in 500 feet. 1000 FEET is another story. the motor doesn't even get going in 500 feet. By that time your off the throttle.

that is about right for that sled in 500 feet. i was running 82-84 , highest was i think 85.

1000 feet of ice i have seen a turbo charged rx1 pull 146 I believe was the speed.

I raced a rx1 ( non turbo) on grass in 500 feet. Beat him by over a sled length. My sled shot right out of the hole. no lag. little ski lift and just screwed out of the hole. :inlove:

i had a mxz 600 ( set up for grass) sucked down, clutched ( agressive trail set up) mild head work, bored cylinders, cylinders were port matched to the exhaust, dynoport exhaust, 96 chisels.

there was a bottle feed mxz 800 pulling high 90 almost 100.

I was sending alot of people back to there set up area's scratching there heads.
zr800, spankled a blair ( trail set up) beat an srx a few times, got my butt handed to me by a bunch of sled to. couldn;t touch the f7's. beat a venom all set up, renegade 600HO.
i had help with the setup from a ski doo clutch guro. ( does sled work on Danny Meyer's grass sleds) he will be in fremont, nh racing. there sleds are sick.

I once heard that the only way a Yamaha would ever break 100MPH is over a cliff... so what'd you expect???? :sarcasm:

Bender was in North Bay this past winter testing with 2 Turbo RX1's. Each ran just over 140mph(perhaps 145ish, I can't recall) in a roll on from the 1000' mark on a 2000' radar run track.

The 165+mph guys (2000') where watching and where very impressed!
Each RX1 ended up lifting the heads and taking out the head gaskets. These sleds weren't trail versions

A local guy has a trail version, just a hair slower than my 1100 Tcat.

But I gotta say, those sleds are awesome!!