helpfull ENGINE PORTING tips for all.

dc2 man

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check this out lads on my research for engine info i had this bookmarked so here it maybe helpfull for all.

i like to make some contributions to good fourms such as this one.
enjoy.

in fact for any serious hobbist like myself i would bookmark this page when you click it below,very handy info in there.

this is a boat engine,but it is zenoah,and they are all identical internally.

http://www.modelgasboats.com/Magazine_Content/Tech_Articles/Engine_Porting.html
 
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evo tuning

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Let me just add something here, when you port a model car engine like this, take into account that a boat has WATER COOLING which cools the engine so much that you can port it to its limit, if you port a rc car engine to much it will simply overheat very quickly and lose performance, now i don't want to put you off guys but just take this into account, also the type of porting they are using is for high revs mainly, most boats are on full chat for upto 20 min at a time do 5 min or less with a car engine on full throttle and it will heat seize due to not having proper cooling

stevo Evo Tuning
 

Ducky

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Wasn't that link already posted on this site; either that or I saw it on HPF previously?! lol

Steve interesting point that the engine is ported for boat use/water cooling, although a couple of other peoples engines have very similar porting work by O'Neils.

How does it compare to what you porting you would do?
:)
 

dc2 man

Reading the Rules!
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limerick/munster
Wasn't that link already posted on this site; either that or I saw it on HPF previously?! lol

Steve interesting point that the engine is ported for boat use/water cooling, although a couple of other peoples engines have very similar porting work by O'Neils.

How does it compare to what you porting you would do?
:)
i never saw that link posted before ducky,sure no harm in posting again
NEVER saw it before
so as you have seen it so could you find it again and send on the link cause i sure never saw it before,just to see where it was posted up
 
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Ducky

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Guess I must have seen it on HBF the first time then, it was buried in a thread on engines but I'm not trawling the threads to find it again! lol Probably worth sticking that link into the engines section though, if it isn't already? :)
 

Timmahh

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Actually, you would be surprised at the differances between a Zen PUM 26 and a Zen G270RC. the exaust ports are shaped differently. i believe the exhaust port is also different, but i think the intakes are about the same size/demension. these subtle changes will mean the motors run differently.

but your correct in saying the general idea is the same.
 

dc2 man

Reading the Rules!
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limerick/munster
Actually, you would be surprised at the differances between a Zen PUM 26 and a Zen G270RC. the exaust ports are shaped differently. i believe the exhaust port is also different, but i think the intakes are about the same size/demension. these subtle changes will mean the motors run differently.

but your correct in saying the general idea is the same.
exactly my idea was just to send the link to show inexperienced people the basics of porting
this is the same method you would use porting any engine 1/5th scale

and ducky i forgot to post it in engines
 

dc2 man

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new porting tips.

so here are a few more links for some of you that may be of a help, and for more to crticize :clown:

of course all these are stuff i have on engine porting,some are based on marine and some not,the first link is to a cool design intake manifold and the second is a tuning guide for sale on e-bay and the rest are some hand picked ones for your pleasure haha:lol::lol:

like i said some porting here is marine engines and some not,generally the same idea.

CHECK OUT THE 100MPH GAS ENGINE AT THE BOTTOM.... COOL HUH?

http://www.modelgasboats.com/Magazine_Content/Product_Reviews/M-Boat_Carb_Block.html
http://cgi.ebay.co.uk/ENGINE-TUNING-PROGRAM-ZENOAH-car-boat-gas-rc-sikk-ETP5_W0QQitemZ360125137236QQcmdZViewItem?hash=item360125137236
http://powerpete2.20megsfree.com/photo2.html
http://www.prestwich.ndirect.co.uk/etp/zenoahtuning.htm
http://www.modelgasboats.com/Magazine_Content/Tech_Articles/CMB_35_Record_Engine.html
 
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Bigger the Better

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Wasn't that link already posted on this site; either that or I saw it on HPF previously?! lol
Steve interesting point that the engine is ported for boat use/water cooling, although a couple of other peoples engines have very similar porting work by O'Neils.
How does it compare to what you porting you would do?
:)
i never saw that link posted before ducky,sure no harm in posting again
NEVER saw it before
so as you have seen it so could you find it again and send on the link cause i sure never saw it before,just to see where it was posted up
:oops:https://www.largescaleforums.com/forum/showthread.php?t=3932&highlight=porting #6:lol:
 

evo tuning

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uk
Wasn't that link already posted on this site; either that or I saw it on HPF previously?! lol

Steve interesting point that the engine is ported for boat use/water cooling, although a couple of other peoples engines have very similar porting work by O'Neils.

How does it compare to what you porting you would do?
:)



hi pal basically i would not use the tuning that is done in that thread as the engine would over heat very quickly in an rc car not to mention use lots of fuel,
pum cylinder heads are alot different than cylinder heads for rc cars, they may look simler to the eye but the exhaust port has different timing and so do the transfer ports, my porting is very different compared to the boat guys
as i tune engines that produce about 5-6+hp but will last 30 min on a tank of fuel, long enough for any final, i also tune them for quality and longlife, my porting is also very very neat and tidy as most of it is done on a cnc machine so ring pick ups are les commen, the heads are also skimmed to raise the compression and match to the piston as every head needs skimming more or less as not all are the same beleive it or not, these are also the phase 1 head kits which are for racing i also do phase 2 kits which use slighly more fuel and give more low end
here are a few pics its hard to see it all properly as its all polished and doesn't take to the camera very well,

http://s95.photobucket.com/albums/l149/djstevieb1/phase 1 cylinder porting/
 

Bigger the Better

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hi pal basically i would not use the tuning that is done in that thread as the engine would over heat very quickly in an rc car not to mention use lots of fuel,
pum cylinder heads are alot different than cylinder heads for rc cars, they may look simler to the eye but the exhaust port has different timing and so do the transfer ports, my porting is very different compared to the boat guys
as i tune engines that produce about 5-6+hp but will last 30 min on a tank of fuel, long enough for any final, i also tune them for quality and longlife, my porting is also very very neat and tidy as most of it is done on a cnc machine so ring pick ups are les commen, the heads are also skimmed to raise the compression and match to the piston as every head needs skimming more or less as not all are the same beleive it or not, these are also the phase 1 head kits which are for racing i also do phase 2 kits which use slighly more fuel and give more low end
here are a few pics its hard to see it all properly as its all polished and doesn't take to the camera very well,

http://s95.photobucket.com/albums/l149/djstevieb1/phase 1 cylinder porting/
The link was not given to show what to do on our motors but included in his Thread to show what porting was.:no:
 

Ducky

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644
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Kent, UK
Thanks for the pictures Steve, interesting that you do a lot of it on a mill and I can see how even the porting it, with perfect edges. I've seen other people add the top holes into the piston, is that to get more mixture into the crankcase?
 

evo tuning

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uk
the holes are to give it more bottom end as they let more gasses into the transfers earlyier,also the piston skirt is rasied and matched to the transfers for 2 bolt or 4 bolt so each piston is different for each engine, and the piston top is skimmed to help with higher revs as the cylinder is skimmed to increase compression, the porting is neat and is nearly identical on every head kit
 
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Ducky

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644
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Kent, UK
the holes are to give it more bottom end as they let more gasses into the transfers earlyier,also the piston skirt is rasied and matched to the transfers for 2 bolt or 4 bolt so each piston is different for each engine, and the piston top is skimmed to help with higher revs as the cylinder is skimmed to increase compression, the porting is neat and is nearly identical on every head kit
Very nice, I notice on Rogers site (RC.Demon) that the kit is only for 26cc engines, do you offer one to take a stroked crank (29cc?) :)

Thanks for sharing the info btw. :)
 

evo tuning

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my engines run better with a std crank in my opinion but we have tested them with 30mm cranks and they do run well but the std crank offers more top end,
i am currently in the process of having a piston modified so you can use any std head kit or ported headkit (without the cylinder base skimmed), with a 30mm crank without stacking gaskets or machining the head, this piston will also increase the std compression quite a bit so will produce awsome low to mid range power, they will be available soon.
if they are to be used with an evo tuning head kit then the cylinder will not be skimmed.
 
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Ducky

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644
Location
Kent, UK
my engines run better with a std crank in my opinion but we have tested them with 30mm cranks and they do run well but the std crank offers more top end,
i am currently in the process of having a piston modified so you can use any std head kit or ported headkit (without the cylinder base skimmed), with a 30mm crank without stacking gaskets or machining the head, this piston will also increase the std compression quite a bit so will produce awsome low to mid range power, they will be available soon.
if they are to be used with an evo tuning head kit then the cylinder will not be skimmed.
Thanks for the heads up, will you be posting on here when they're available? :)
 
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