Tillotson 225

JTSpeedDemon

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I don't think it's possible to bore these small engines out 0.08"!! The max OEM recommendation for a Briggs flattie is 0.03", and all these small engines have thin wall blocks.

I don't think you'd need to worry about overheating, because I think you'll have a hole in your cylinder before that happens.

Why 0.08"?? Is there a particular piston you want to use? Dynocams has lots of Wiseco and a few Burris pistons for sale.
 

JTSpeedDemon

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It may be a differently designed block for the 225, though.

I bet Flyinhillbilly can answer this, I'll let someone else chime in.
 

Flyinhillbilly

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You can see in the pictures that there really is t much flashing, or casting flaws. These blocks have a lot of extra bracing built in, and they are very much worth the $100 that they’ll set you back in my opinion.
This one is slated to be a 14.5 cubic inch open motor. I’m going to do a couple of videos of the build as soon as the rest of the parts come in.
 

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karl

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Can i used everything from my hemi on the tili 72mm block

Maybe the pull starter and ignition coil , not much else

How much of the stock predator parts do you want to install in the nice block would be the question.

You can buy just the long block , link was in the first post.

https://www.gopowersports.com/225rs-tillotson-engine-long-block/

I think you missed the point , just buy the whole 225 engine or work with what you have. Impressive power output is achievable with the predator's stock bore and stroke. Reaching the point of diminishing returns on a $100 china clone is not much fun.
 

Mercado

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Im waiting for my new tillotson 72m block to come and make it 72x56 with a hemi head on a weld chamber and a black mamba jr cam with 1.2 rollers let see the power on this set up

---------- Post added at 09:15 PM ---------- Previous post was at 09:14 PM ----------

The 56mm its a clone crank and rod instead of the 55mm crank i wanted some thing a little diffrent
 

Flyinhillbilly

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Im waiting for my new tillotson 72m block to come and make it 72x56 with a hemi head on a weld chamber and a black mamba jr cam with 1.2 rollers let see the power on this set up

---------- Post added at 09:15 PM ---------- Previous post was at 09:14 PM ----------

The 56mm its a clone crank and rod instead of the 55mm crank i wanted some thing a little diffrent

I’m excited to get going on building mine too. I’m still waiting on the head. It should be a pretty mean little motor. I’m going with a tunnel ported warhead with 34/28 valves, billet 1.3 rockers, 2.3 super alloy stroker crank, custom ground 360 lift cam, all fed by a Clements 34mm flat slide carb. This one should be a high rpm screamer.
 

Flyinhillbilly

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Mine is going to be 238cc, so for 10cc I should’ve just bought one of those. I guarantee it would’ve been way cheaper.
Tillotson has really stepped up over the last year.
 

Mercado

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Update ok engine is running good change the cam for a mamba custom 290 lift 246 duration on 36 springs but the issue is that i cannot get it to past 7000 rpm could it be that it needs more timing to get it to pass that 7000rpm to 8000 at least like 34 or 36

---------- Post added at 08:08 PM ---------- Previous post was at 08:07 PM ----------

Now i have about 28

---------- Post added at 08:09 PM ---------- Previous post was at 08:08 PM ----------

Is it truth that the more timing you put on the engine the more rpm you will get base on the duration of the cam or not
 

Flyinhillbilly

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The timing retards as rpm increases. You can help it by opening up the coil gap, but I like to run my gasoline engines at 32-36 so you might try advancing the timing a little and opening the coil gap to .060
 

Mercado

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Ok i install a 34 timing arc flywheel but now it only goes up to 7800rpm and noe its a 236cc ita 72x58 with the ec 236 crank kit what could be my problem
 

Minibikeaction

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The 225 block is already 72mm bore, the casting all looks really nice, and I really love all of the extra bracing.
Hey man I’m new to the group, I’m running a 225RS with a 24mm mikuni flatslide. I have a 38 pilot and 140 main I’m getting brake up at high rpm, I think I need to be somewhere around 170 main, 20 pilot. I also have some parts to throw in the mill. Dynocams .308, black venom 1.3 roller rockers, maybe you could help me out? If so shoot me a dm please man 🙏 I appreciate it
-Kevin O’keefe
 
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