357 MAGNUM (02 motor build) Reincarnation of #5 The 357 build

YAMAHAULER · Dec 4, 2012

Figured I'd get my motor build started since it is my winter project.

motor is tore down and ready for the build in basement
The operating table Lol!

gonna be going with the 84mm Wiseco 10.25:1 piston kit and Cometic gaskets
stock crank and jug will be going to my local shop for rebuild and bore & hone and head will be getting a mild p&p to compliment ???? stay tuned for more......

duneracerweston · Dec 4, 2012

You should get the deck set or drop the jug! Puts compression at 11.02:1! Otherwise your motor sounds a lot like my motor before tore it down

88WarriorBoy · Dec 4, 2012

Dude are the fins on that head caked with mud ? lol

YAMAHAULER · Dec 4, 2012

88WarriorBoy said:
Dude are the fins on that head caked with mud ? lol

not at all just dusty this motor has been sitting out in my garage since last winter when the connecting rod bearing failed

YAMAHAULER · Dec 4, 2012

duneracerweston said:
You should get the deck set or drop the jug! Puts compression at 11.02:1! Otherwise your motor sounds a lot like my motor before tore it down

you mean base gasket delete? and can I still run pump gas like 92 octane with 11.02:1 comp?

I'm gonna be running the WEB .390/.390 cam

88WarriorBoy · Dec 4, 2012

yeah just rtv the jug to the bottom end

duneracerweston · Dec 5, 2012

You can run pump up to 12:1 but if its not perfect tune at 12:1 it will implode... but 11.02:1 your well beyond safe

Mathius · Dec 5, 2012

I still think running with no base gasket is sketchy...

duneracerweston · Dec 5, 2012

Never had any issues on mine

DeadLastRacing · Dec 5, 2012

duneracerweston said:
but 11.02:1

Is that the accurate ratio?

duneracerweston · Dec 5, 2012

Yep, provided Wiseco got their ratio right with their 10.25:1 rating, dropping the jug gasket you loose a little less then 3cc (2.6cc) in chamber size so that bumps it from 10.25:1 to 11.018 or 11.02:1 or just 11:1 how ever you want to round it.

WV98YFM350 · Jan 26, 2013

Other than the added comp. Why run without base gasket? I, too think that sounds pretty sketchy!

1998yamahawarrior · Jan 26, 2013

WV98YFM350 said:
Other than the added comp. Why run without base gasket? I, too think that sounds pretty sketchy!

using RTV in place of the base gasket is a common thing for us guys since we dont have the piston selection that other quads. Apparently Weston just decided to do the math and figure out what it would be bumped up to.

PHANTOMLORD · Jan 26, 2013

Humm i work on cars and say if it had a gasket put one back in its place, i have found to many times if you dont then intime things happen,,,,

Gen1Pat · Jan 26, 2013

PHANTOMLORD said:
Humm i work on cars and say if it had a gasket put one back in its place, i have found to many times if you dont then intime things happen,,,,

Agreed. I'm still leary about doing it. I've been thinking about doing it on the stroker, and getting 11.25:1 outta it. The base gasket is more to keep the splash oil from the crank from leaking out. All the pressurized oil from the top end oil galley is sealed with an o-ring between the cylinder and crankcase, and by another between the cylinder and head. Some good high temp rtv will work, just like it does on transfer case halfs.

duneracerweston · Jan 26, 2013

The only thing that makes it iffy is that your prep job needs to be as good as you can have it or you will hive a extremely minor oil leak on the front left head bolt, but ive seen more gaskets leak there then silicone does. Im building a 11.6:1 motor running2 jug gaskets to lower comp from 12:1. Otherwise I would build the same motor again.

YAMAHAULER · Feb 7, 2013

well boys I have officially scrounged up all the parts to finally get this build finished only thing left to do when the piston gets here is have the jug bored & honed and she can start going back together hahaha!

alex456123 · Feb 7, 2013

Hey hauler what happens when the next rebuild comes round? If ya bore it it won't be a 357!!!

hno:

YAMAHAULER · Feb 7, 2013

Then it goes .050/359
but it more than likely won't be needing another rebuild after this in my lifetime

YAMAHAULER · Feb 15, 2013

some of the final pieces to the build! and the crank is in the shop getting rebuilt, only thing left is to bore & hone the jug to match the 84mm piston then we can slap it all together!

357 MAGNUM (02 motor build) Reincarnation of #5 The 357 build

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