Twin OS 4stroker in a Tmaxx hybrid

[Lason]

Originally posted by Rob D
they run on regular nitro fuel i was reading about the os 4strokes today

COOL! I wonder how they properly lube the valvetrain and if they usually have a longer life than their 2 stroke brothers? Also, what temp they usually run at. Sorry for all the questions but I'm a real car buff and always liked the idea of a 4 stroke in a model car/truck.

<-------Doing frame up resto on '81 vette!

 

[Rob D]

check out o.s web site i think theres some info on there ..book said there were pretty good as long as you didnt lean them way down and rebuilds were higher..

But i think rebuilds were 50% - 100% more

 

[3maxxman]

The engines run on glow fuel, no less than 18% oil and the seem to like 20% nitro best. They will last for 10 to 15 gallons running under 300*f, rebuilds are cheap since they are ringed engines as long as you don't lean them too much and score the sleeve you can just replace the ring and your good over and over till you wear out the sleeve.

FYI, I am running the engines VERY rich to keep the power down, I have not been over 170*f in the videos and the carbs are set at about 2 1/2 turns out. When I ran a single 40 temps were at 270*f consistantly and the needle was at 1 1/2. The engines do produce more smoke than a 2 stroke because it is a sealed combustion chamber so you are burning more of the oil and fuel than the 2 stroke will. Fuel economy is better than a .21 2 stroke even though the engine is twice the size, it takes 2 times the displacement for 4 stroke to equal a 2 stroke, but the torque of the 4 stroke is massisve and the horsepower is small (less than 1 hp.)

I have some video of my twin running side by side with a single 40 on the track, it pretty cool the single drowns out the sound of my twin, but the twin can catch and pass anytime it wants.
Want more reading on the engines??? Click the pic.

 

[mjime714]

Thanks for the info, images, pictures and links! I learned a lot from this thread. Lately I have been seeing a lot of custom jobs and am slowly being inspired to do one of my own. You guys are killing my wallet. As soon as I put a little green in there, it spits it right out.

 

[Rob D]

You mean your green actually hits the wallet first :jester:

 

[nitro dave]

Originally posted by 3maxxman
nitro dave, I live in Juanita (North Kirkland). The track is called Maxxland (it is in Sammimish) and is open to the public. It's in Cory's backyard so you need to call him everytime to go up, lot's of people bash there had some good gatherings and more people show up every weekend.
(Click the pic for more info). Hope to see you there.

Thanks for the info....i'm going to have to come up there and bash...looks like a fun place to run.

 

[mjime714]

Originally posted by Rob D
You mean your green actually hits the wallet first :jester:

I'm like a transport from my bank to the hobby shop.

 

[RSfan8]

very awesome car man. what does it weigh!?

 

[3maxxman]

13.5 pounds with no fuel!