DBXL Tear the ole girl down

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There's a company called rc4wd. They have a great selection option for 1/8 and 1/10 scale. Kinda pricey but they have a lot of tires.
And I'm more after the hight. Running the bajan front tire size is a smaller diameter tire then the dbxl comes with. And I have a set so may as well toss them on.
 
So as promised. I'll point out o few observations first. I really want to hand it to zen for their very nice transitions from carb to spacer and carb spacer to block. It's all but seamless. ? deffinatly very well thought out design. 52351
My only complaint about it (which may not even be valid in a piston port) is the intake is very smooth. Normally you want a little roughness to help with fuel atomization.
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Its kinda hard to see the whole port but its smooth as a babies arse.
Exhaust port is just as nice. Even the gasket doesn't overhang the port. Very impressive.52353
Anyone notice anything wrong in this pic. Mind you I've never had this engine apart....52354
Here's the head side
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For those of you that don't know. The base gasket is on wrong? should have been turned 90*
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First thing I did was finde tdc and bdc and mark my ports out. Normally I'd toss a degree wheel and get anal about port opening and closing and trying to find blow down. But honestly I don't race so I'm just gonna open the ports up a bit, check squish, and mod the transfer covers a bit. As I don't have a spare head laying around if I muff it up I'm a bit screwed lol.
 
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Some before pics. I will admit this is the smallest cylinder I've ever messed with. Normally it's for a saw and at least 47 to 50cc...
 

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Ok finished product more or less. I didnt go too crazy in the intake side as I don't have a bullet intake manifold. Widened the port a bit and opened the inlet side to match up with what I could take out of the intake. I left it a little rough as it should help fuel ti atomize. Cleaned up the transfer ports a bit and put an angle on the bottom edge of the cylinder. Blew the exhaust out as much as I thought I could. Had to open up the header as well to match it. Btw. The DDM dominator header was a bit smaller then the g320 factory exhaust port so not opening it up to match will just choke the engine down. I didnt do anything with the bottom end as the bearings are good yet and I didnt feel like messing with it. I'm debating if I want to mess with the piston or not. I had thought about adding a boost port to it but I'd have to do a bunch if measuring as there isnt much room in this tiny cylinder ? here's some after pics for you.
 

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Ok finished product more or less. I didnt go too crazy in the intake side as I don't have a bullet intake manifold. Widened the port a bit and opened the inlet side to match up with what I could take out of the intake. I left it a little rough as it should help fuel ti atomize. Cleaned up the transfer ports a bit and put an angle on the bottom edge of the cylinder. Blew the exhaust out as much as I thought I could. Had to open up the header as well to match it. Btw. The DDM dominator header was a bit smaller then the g320 factory exhaust port so not opening it up to match will just choke the engine down. I didnt do anything with the bottom end as the bearings are good yet and I didnt feel like messing with it. I'm debating if I want to mess with the piston or not. I had thought about adding a boost port to it but I'd have to do a bunch if measuring as there isnt much room in this tiny cylinder ? here's some after pics for you.
Nice, here's a suggestion, why not try an ramp the piston?
 
Nah I'll loose torque. Not worried about killer rpm. I can run a taller gear if need be. I had to order some gaskets anyway so I got the DDM billet intake manifold. So once that shows up I'll hog out the intake some more. I have some teflon gasket stock here I may try and make a heat shield out of for in between the carb and gasket. I checked my squish (piston to head clearance) and got .018" I normally like .020 to .022" so I ordered the copper .005" gasket that will give me .023" should be ok. I didnt have any shim stock laying around to make my own and for $6.00 I cant get a roll as cheap as the gasket.
Oh one more pic for now how's this for a nice port to manifold transition
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No obstructions there ?
So now why has the squish changed on yo ur motor? You said that you only did the topend? in theory coz you did not add a stroker you should just be just able to add stock gasket and bobs your auntie ?
. I checked my squish (piston to head clearance) and got .018" I normally like .020 to .022" so I ordered the copper .005" gasket that will give me .023" should be ok
 
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Less squish equals more compression. I allways check when I play with the ports. Most of my saws don't even run base gaskets. You would be amazed the difference .020" makes. The factory zen gasket (the one I took off of mine) measured .021" the squish with out a gasket I measured at .018". .018 +the .021" gasket = .039" that's way too much clearance imo. Like I said before I like to keep it around .020" if I can help it. So with that .005" gasket DDM offers (which I'm sure will compress a bit) I should have .022" squish in my engine. So more compression should also have more bottom end torque and may even gain a few rpms up top. I should have pumped the engine before and after for a compression comparison. I forgot about doing that. I only run high test anyway so It should be allright
 
Well my wonderful 3 year old just feked me hard. She was playing down in the basement when we were cleaning up after dinner. Start hearing this banging. Run down stairs and shes smacking my crankcase off my work bench?. Ruined my piston I spent so much time on and to boot when she saw me she tossed it in the trash bin. So now it's all tore apart and I need to order more parts for it. Honestly the piston is coming out of her piggy bank.
 

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Well my wonderful 3 year old just feked me hard. She was playing down in the basement when we were cleaning up after dinner. Start hearing this banging. Run down stairs and shes smacking my crankcase off my work bench?. Ruined my piston I spent so much time on and to boot when she saw me she tossed it in the trash bin. So now it's all tore apart and I need to order more parts for it. Honestly the piston is coming out of her piggy bank.
That totally sucks man. Ouch! Especially since you spent so much time on it, i know exactly what that feels like ??? notice how no one is having good luck with their engine? @cardarear 's won't start, mine having that crankcase issue, you this, just sucks ass big time!
 
Well my wonderful 3 year old just feked me hard. She was playing down in the basement when we were cleaning up after dinner. Start hearing this banging. Run down stairs and shes smacking my crankcase off my work bench?. Ruined my piston I spent so much time on and to boot when she saw me she tossed it in the trash bin. So now it's all tore apart and I need to order more parts for it. Honestly the piston is coming out of her piggy bank.
WWWWWWWHHHHHHAAAAATTTTTT! NNNNNNNNOOOOOOO????
That totally sucks man. Ouch! Especially since you spent so much time on it, i know exactly what that feels like ??? notice how no one is having good luck with their engine? @cardarear 's won't start, mine having that crankcase issue, you this, just sucks ass big time!
Bad luck come in three's? so ill be getting my motor next so, im gonna a beauti in my hands? Thanx for taking those hits for the team boyz:rolleyes::oops::LOL::LOL::LOL::rage:;)(y)
 
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