Building a Racer

[Tomo]

hi ,
Old steel tanks can have a rust patch on the inside from water/condensation in the fuel .
This will start to discolour fuel from the finest rust particles ,enough to block jets after a while of operation . The discolouration will not be noticed in a 2 stroke oil fuel mix .
tomo

[smudvapor]

hi ,
Old steel tanks can have a rust patch on the inside from water/condensation in the fuel .
This will start to discolour fuel from the finest rust particles ,enough to block jets after a while of operation . The discolouration will not be noticed in a 2 stroke oil fuel mix .
tomo

Not taking any chances, I am going to clean it out and seal it before it goes back in.

[smudvapor]

Here are some pics I took today. I did not get to work on it because I spent the day working on the other one.

[smudvapor]

Use a pipe off a Scorpion 440 snowmobile. If I remember correctly, one flows better than the other model......the Whip I think is the model to get one from, although I can't say for sure. Also, if your JLO 440 is a 4 bolt head, upgrade the heads and jugs to 6 bolt ones/5 port. This makes for a very potent engine. My 440 Thunderchief racer has a 440 5 port/6 bolt head and it will outrun a Superchief.........ask Hydromike, he has the same engine in one of his racers and his will do the same.

Here are most of the parts you'll need to build one hell of a 440. These will all simply bolt right onto your JLO 440 bottom end.


Scorpion Cuyuna 440 6 Bolt Cylinder Jug 1 PTO | eBay

Scorpion Cuyuna 440 6 Bolt Cylinder Jug 2 Mag | eBay

1979 Arctic Cat Scorpion 440 Cuyuna Exhaust Manifold w Muffler | eBay

Thanks for the info, I ordered all three. The jugs came today and they look like new! Great price too!

[jpswift1]

Glad I could help! You're going to love the performance of a fresh a fresh 5 port, 6 bolt head 440. It's going to make for one fast racer! Are you going to run dual carbs on it? If not, you'll need the Cuyuna 440 intake manifold and plastic intake manifold spacers. Keep us updated on it.......looking forward to seeing it at Ashtabua!

[millerperf]

I was thinking of trying to come to astabua if I can finish my max iv I have it mocked up with the apex Yamaha motor , my buddys say I should take it out !I have a new 503 rotax aircraft engine , a 670.rotax and a 3 cyclinder 700 rotax what would you guys do can I race it with the big engine time is getting short!what do you think jeff

[hydromike]

what would you guys do can I race it with the big engine time is getting short!what do you think jeff

If you really want to race it at Ashtabula, I'd keep it simple and throw the air cooled 503 in it and put some 21" tires on it to get it down low. You can change the primary spring in the clutch to a two stroke spring and you'd be in good shape. Of course, you need a roll cage and a seat belt, too. You could probably get a way with the stock gearing; the rpms of the Rotax will make up for the 26 tooth sprockets.


We've had folks make it up from Florida before. It's a long haul, but you can get there early and make a week out of it.

[smudvapor]

Glad I could help! You're going to love the performance of a fresh a fresh 5 port, 6 bolt head 440. It's going to make for one fast racer! Are you going to run dual carbs on it? If not, you'll need the Cuyuna 440 intake manifold and plastic intake manifold spacers. Keep us updated on it.......looking forward to seeing it at Ashtabua!

I am going to run a dual carb set up. I bought it all a while back and I haven't taken it out of the box yet.

[hydromike]

So you have the intakes and the carb flanges for the 5-port? Where did you pick those up? There have been folks looking for them for a couple years, and outside of Zerkle, I didn't know where to forward them....

[jpswift1]

I've got two Mikuni carbs, intakes, and everything required to run dual carbs on a 5 port, 6 bolt head Cuyuna if anyone needs them.....I'll sell the complete setup for what I bought it for, $99........intakes, spacers, carbs, and all.