Solo 665/681 Snellerized Style

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I bought a NOS Solo 665 last fall with the intentions of building it with a Dolmar 7910 topend. I bought the topend and it's just been setting there. I finally got around to mounting it to see how much needed removed from the squishband, since the 665/681 has a 2mm longer stroke. Then it set for several more weeks. Friday I had Nik, @FATGUY , mill a slot in my PVC mandrel to accept a cutting tool. It requires taking .060" out of the squishband, with the use of the thinner rubber coated Dolmar gasket, for a final squish of ~.020". Without having raised the exhaust up, compression is 235 PSI. However, the exhaust is way down at 108.5°. I don't have an accurate measurement yet, but it looks like it will take about .130" just to get it up to 100°. It may end up higher.

I have some questions on the bottom end. I don't recall the details, but I thought I had heard of multiple issues with 681 cranks. On the other hand, a couple reliable sources have run these as high as 240+ compression and even on nitrous with no issues. I'd rather true and weld the crank now though if there might be issues. Does anyone have the lowdown on if there are crank issues with these?

Crank bearings... Am I correct that the flywheel side is a 6202? How about the PTO side? Is it a proprietary bearing? I'm toying with the idea of putting ceramic mains in it, since this is a fun build for myself.

Are the main bearings, seals, and crank gasket the same as the 7900/7910?

I'd appreciate any info you guys might have on these. If not, I'll fill in the blanks as I go.

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The crank going out of phase was pretty common with these saws sometimes even on stock saws. A few guys were tig welding the cranks, but if I remember this was difficult, and had at best mixed results and most gave up on these saws altogether. They were strong crazy strong saws when done up right. Give EC call, or DD they both have the knowledge when it comes to these saws

Are you going to Devcon the intake?
 

I wanna throw my thought in here and Ya'll can see where the build takes you.
Brad I do believe if you build this saw just like a 7910 you will find the 7910 is a stronger saw. Here's my first build built just like a 7910 with more comp. It's slower than a 7910.
 
You're second saw and Randy's are really hauling the wood!
Well I'll be watching as you build. But i think you will be extremely unhappy at 100. Then your gonna do 98 and think hmm that's more like it. Then youll hit 96 and the whole attitude of that saw will change! That's my thought. Now let's see what you figure out! Build away!
 

Let me say this isn't a real good vid but let me give you the details of these 3 saws before you judge.

390xp- this saw is more of what I call a loggers build. It's just less agressive. Little less comp, the port timing is the same but the ports themselves are less agressive. This saw was actually stronger with a 36" bar.

665- this is my 98 saw.

7910- well this is actually a brand new 6400 with a 7910 p&c. I can actually buy and build them cheaper this way and I gain a higher rev limited coil. In the vid that's literally cut 3 and 4 on a brand new build!
 
Well I have yet to lay my hands on a 681 lol. But the 665/7910 is the fastest one I've built. If i can just figure out for sure where the trans like to be.
 
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