Nitro engine porting/modding

[JB COMP]

Okay, Here's a thread on how to port/mod your nitro engine for more power and fuel mileage.

Here's an article in a magazine I found online.


http://img.photobucket.com/albums/v218/BCSavage/porting/Photo020.jpghttp://img.photobucket.com/albums/v218/BCSavage/porting/Photo021.jpg
http://img.photobucket.com/albums/v218/BCSavage/porting/Photo022.jpg


Its got some good info in it, but for the more skilled modders out there, they would want to look into timing mods (that's where the real power gains are)

http://image2-9.rcuniverse.com/e1/forum/upfiles/300296/Vp38389.jpg
http://image2-2.rcuniverse.com/e1/forum/upfiles/300296/Rc41772.jpg
http://image2-8.rcuniverse.com/e1/forum/upfiles/300296/Mc50458.jpg
http://image2-6.rcuniverse.com/e1/forum/upfiles/300296/Sq18106.jpg

Those pictures are of a TRX2.5R that I modded and has the timing modded.

How you can tell if the timing it modded is to look at the top of the ports if the chrome is gone then that means its bee modded like this

http://image2-4.rcuniverse.com/e1/forum/upfiles/300296/Mo16014.jpg

http://image2-8.rcuniverse.com/e1/forum/upfiles/300296/Ca80438.jpg

I found out after I took these pictures that you're suppose to cut the ports at the same angle that the ports where (before modding) so the whole port should be dechromed not just part like in the pictures.

I hope people can learn from this thread and have fun with modding/porting their engines.

Remember that when modding you can ruin a engine very fast so practice on a old sleeve a few times before starting on a good sleeve.

Porting you can get away with some stuff but when modding timing you can't get away with any mistakes or your engine will be a very expensive paper weight.

This thread is not to take away from people like Adam at ABmods.com because Adam has been modding engines for a while and he owns a dyno so he has proven results.
On a picco P3 28 it has stock 1.8HP on the dyno and after Adam mods it is has 2.4HP on the dyno.

I hope this thread will go far and help many of people.

[roadrunnr43]

google "grooved cylinder heads". ive seen/heard of people doing this to 1:1 engines and lawnmowers. you take the heads off of your engine, and put a groove from the plug, to the edge of the combustion chamber. theory is that it allows the explosion to reach the very edge of the piston easier. now the effects for most people is, lower RPMs, cooler temps, and increased torque through the bottom/middle of the power band. I have never actually seen an RC cylinder head and I am wondering if the glow plug would be in the way,
any info would be nice

[JB COMP]

google "grooved cylinder heads". ive seen/heard of people doing this to 1:1 engines and lawnmowers. you take the heads off of your engine, and put a groove from the plug, to the edge of the combustion chamber. theory is that it allows the explosion to reach the very edge of the piston easier. now the effects for most people is, lower RPMs, cooler temps, and increased torque through the bottom/middle of the power band. I have never actually seen an RC cylinder head and I am wondering if the glow plug would be in the way,
any info would be nice

I've seen it done before on RC's, but there was a big "war" on it if it worked or not. Then you have to think about if its worth losing the compression. (what ever metal you remove from the head, you're taking that much compression away.

Please post pictures of any engine that any has modded.

[roadrunnr43]

im guessing that the most of the people that it didnt work for, was because they took to much out. a hacksaw blade would probably work best.

maybe ill have to try it on my dtx .18;)

[JB COMP]

im guessing that the most of the people that it didnt work for, was because they took to much out. a hacksaw blade would probably work best.

maybe ill have to try it on my dtx .18;)

I heard you want to run your groove from the Boost port to the exhaust port.

You don't want to use a hack saw:eek: use some small 4" files or a dremel with a pointed bit.

You might want to lower the head as well.

[colintrax]

I've modded my engine, polished crank and rod sanded bottem of sleeve and enlarged hole in piston for more boost, several scalops, but please do not shave below the boost port on the outside this will just take away speed, your supposed to angle the top of the boost port upwards on the inside.

[JB COMP]

I've modded my engine, polished crank and rod sanded bottem of sleeve and enlarged hole in piston for more boost, several scalops, but please do not shave below the boost port on the outside this will just take away speed, your supposed to angle the top of the boost port upwards on the inside.

What?

You don't want to have a mirror finish on the crank or sleeve because the fuel will stick where ever its a slick surface.

[colintrax]

why would the fuel stick to it? I haven't had any problems since I've done it.

[JB COMP]

why would the fuel stick to it? I haven't had any problems since I've done it.

When its smooth if gives the fuel a bigger area to bead on then if it was a little ruff.

I heard this from some of the best modders around. You want to polish it your crank and sleeve just don't put a "mirror" finish on it.

[colintrax]

Ok thanks I didn't know that, I guess I should check the crank just to be sure.