Engine Modding

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Judicator

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Chelmsford, MA
My buddy just got back from college and is going to get into Nitro RC and engine modding, Anyone have some nice Info websites on Sleeve/Crack cuts? I lent him my 2stroke book to read to give him and idea but he's unsure about the cutting and all on a runnign engine. Any info would be great for him to read. =)
 
You can learn how a 2 stroke engine works from a book... But you cant LEARN how to modify from a book. Its like trying to learn how to properly tune full scale engines from a book... theres just to many variables. It honestly just takes years of R&D and trial and error to REALLY know what your doing with these engines.
 
Ya i just meant more alone the basis for him is about the sleeves and cranks. I know angle and depth of the cut is a biggy but every sleeve and crank are different. Different places to cut or the all the same pretty much.
 
it depends on what kind of engine it is if its a stock engine Ive seen where some grinding on the crank induction port to make it sharp could help, fang the ports. there is alot on a stock engine that can be done to gain performance. but a Picco or LRP engines the work is already there. that is why they are alot faster than a stock engine. I have a little exp modding engines. ive done two so far for my Savage X a F4.6 and a losi 454 was happy both times. because I know the basics and how to use a timing wheel. and also not to go too far an ruin a engine. Understanding port timings and how these little engines work is a starting point. then from there you can look at your port timings and see if anything can be improved.

the cuts in the sleeve you need to know where your block contacts the sleeve and where the ports in the block are. you can then fang the ports on the sleeve to help direct more air/fuel mix into the combustion chamber. on a stock sleeve their is usually one fang on each side of the transfer ports pointing away from the exh. this is done so it directs air/fuel away from exh. port. these mods called flow mods can make your engine a little faster and more effiecient. flow mods is not rocket science. but don't get too crazy with removing material off the sleeve. the engines port timings and how to change the timeing is where it can get tricky. this is best left in the hands of the professionals. cause its easy too fook up.
 
it depends on what kind of engine it is if its a stock engine Ive seen where some grinding on the crank induction port to make it sharp could help, fang the ports. there is alot on a stock engine that can be done to gain performance. but a Picco or LRP engines the work is already there. that is why they are alot faster than a stock engine. I have a little exp modding engines. ive done two so far for my Savage X a F4.6 and a losi 454 was happy both times. because I know the basics and how to use a timing wheel. and also not to go too far an ruin a engine. Understanding port timings and how these little engines work is a starting point. then from there you can look at your port timings and see if anything can be improved.

the cuts in the sleeve you need to know where your block contacts the sleeve and where the ports in the block are. you can then fang the ports on the sleeve to help direct more air/fuel mix into the combustion chamber. on a stock sleeve their is usually one fang on each side of the transfer ports pointing away from the exh. this is done so it directs air/fuel away from exh. port. these mods called flow mods can make your engine a little faster and more effiecient. flow mods is not rocket science. but don't get too crazy with removing material off the sleeve. the engines port timings and how to change the timeing is where it can get tricky. this is best left in the hands of the professionals. cause its easy too fook up.

I think its been dyno proven that port and polishing sleeves do nothing .. It's all about re timing if you want to make more power.. Roto and port timing (cuttin chrome)
 
I think its been dyno proven that port and polishing sleeves do nothing .. It's all about re timing if you want to make more power.. Roto and port timing (cuttin chrome)

oh really where is that? can you back that up? I can back up my claim with a video of before and after flow mods that they do make more power.
 
it depends on what kind of engine it is if its a stock engine Ive seen where some grinding on the crank induction port to make it sharp could help, fang the ports. there is alot on a stock engine that can be done to gain performance. but a Picco or LRP engines the work is already there. that is why they are alot faster than a stock engine. I have a little exp modding engines. ive done two so far for my Savage X a F4.6 and a losi 454 was happy both times. because I know the basics and how to use a timing wheel. and also not to go too far an ruin a engine. Understanding port timings and how these little engines work is a starting point. then from there you can look at your port timings and see if anything can be improved.

the cuts in the sleeve you need to know where your block contacts the sleeve and where the ports in the block are. you can then fang the ports on the sleeve to help direct more air/fuel mix into the combustion chamber. on a stock sleeve their is usually one fang on each side of the transfer ports pointing away from the exh. this is done so it directs air/fuel away from exh. port. these mods called flow mods can make your engine a little faster and more effiecient. flow mods is not rocket science. but don't get too crazy with removing material off the sleeve. the engines port timings and how to change the timeing is where it can get tricky. this is best left in the hands of the professionals. cause its easy too fook up.

I know how to time, cut timing in the ports and why, how and to what profile. But I'm also friends with Robin and have his, AB mods, and JP mods mills to have seen how and why.


cause its easy too fook up. <--- please don't go around sensors.

But like you say here I know how and have done mods but I also buy the goods from the hands of the best...

oh really where is that? can you back that up? I can back up my claim with a video of before and after flow mods that they do make more power.

Adam from AB mods post is just above yours here he has a X dyno ... ask him how much power is in the "fangs" you speak of. I'm not about seat of pants tuning.
 
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so flow mods do nothing, they don't add power, they are for looks. hmmm.

more bottom end = no power gain
more rpm = no power gain

yea, that makes sence, Maybe not an increase in HP or TQ numbers as per a dyno, but if my truck launches faster, or has a higher top speed, something must have changed.

Just like a lighter crank or hemispherical pistons in a 1/1 make it "FEEL" like its better, but there is no real change
 
Thanks midnight, and FreddyJ.
I stick up for those who have stuck up for me.

I may be somewhat new to this whole nitro mightro mumbo jumbo thing, but Ive picked up alot pretty quick Id Say. And to say that modding an engine gives you low end "power" and a higher RPM, well obviously there is a slight gain somewhere to achive this.

Plus, since I'm waiting for Robin to feel better, so I can get my LRP.30 modded and piped, I don't want to hear any of this "it doesnt do anything" talk, LOL.
 
so flow mods do nothing, they don't add power, they are for looks. hmmm.

more bottom end = no power gain
more rpm = no power gain

yea, that makes sence, Maybe not an increase in HP or TQ numbers as per a dyno, but if my truck launches faster, or has a higher top speed, something must have changed.

Just like a lighter crank or hemispherical pistons in a 1/1 make it "FEEL" like its better, but there is no real change

I am going off what Robin form ERCM mods and Adam from AB have told me when I say, they do nothing. I know I have a picco (from Robin).28 that revs into 38500- 40K RPM that has NO flow work .. all timing. That is a fact I can prove .. I tend not to argue when pros tell me this stuff.

I also know making the crank lighter (in a glow mill) also lowers crank case volume and in the end don't help (From Robin.. Also discussed it with Adam) Unless you want it to shake out of the truck its in ... Then go for it! Nothing beats man made harmonics to ruin a motor. But if your going for a 1 gal ripper just to win a drag title, its worth it! If you know how to put the volume back into the crank case .. If he has the time robin will do this for a extra hundred + on top of his mod price. Well, it may not be available to the public but I know he has done it in one picco out there 4 sure ..

I do know this.. modding is a closely guarded subject. The Pros don't give hints. Some have there OLD work posted in threads and do jobs today that don't look anything like what they posted years ago.. You can go and copy every pic you see on the net and get nothing out of your motor. I used to talk to Robin Hours a day for months in good detail too and I still don't know anything. What I do know, I wont share.. As it was entrusted to me. But again I don't know much other then theory and slight details.
 
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OK guys back on topic ... Fell free to start a new topic if you all want to rag chew I delete all the off topics Less the new guys first posts and the welcome in ...


My buddy just got back from college and is going to get into Nitro RC and engine modding, Anyone have some nice Info websites on Sleeve/Crack cuts? I lent him my 2stroke book to read to give him and idea but he's unsure about the cutting and all on a runnign engine. Any info would be great for him to read. =)
 
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I am going off what Robin form ERCM mods and Adam from AB have told me when I say, they do nothing. I know I have a picco (from Robin).28 that revs into 38500- 40K RPM that has NO flow work .. all timing. That is a fact I can prove .. I tend not to argue when pros tell me this stuff.

I also know making the crank lighter (in a glow mill) also lowers crank case volume and in the end don't help (From Robin.. Also discussed it with Adam) Unless you want it to shake out of the truck its in ... Then go for it! Nothing beats man made harmonics to ruin a motor. But if your going for a 1 gal ripper just to win a drag title, its worth it! If you know how to put the volume back into the crank case .. If he has the time robin will do this for a extra hundred + on top of his mod price. Well, it may not be available to the public but I know he has done it in one picco out there 4 sure ..

I do know this.. modding is a closely guarded subject. The Pros don't give hints. Some have there OLD work posted in threads and do jobs today that don't look anything like what they posted years ago.. You can go and copy every pic you see on the net and get nothing out of your motor. I used to talk to Robin Hours a day for months in good detail too and I still don't know anything. What I do know, I wont share.. As it was entrusted to me. But again I don't know much other then theory and slight details.

On some of the first post i made at SC when I was looking for engine modding info, Adam told me that if done right flow mods can make a little power and make the motor run more efficiently. and he helped me a bit. I can dig them out if you like.

here is a guy who is asking for engine modding info just like I was back then and people helped me out, so someone gave me a break and I would like to return the favor to guys who would like to do this work themselves. doing this stuff yourself succesfully yeilds great self satisfaction of a job well done. we did get off topic a bit. and am sorry for the inconvienece.

now back to topic. flow mods are a great way for a guy starting out that wants to learn. i wont get into timing cause its easy to mess up.
 
On some of the first post i made at SC when I was looking for engine modding info, Adam told me that if done right flow mods can make a little power and make the motor run more efficiently. and he helped me a bit. I can dig them out if you like.

here is a guy who is asking for engine modding info just like I was back then and people helped me out, so someone gave me a break and I would like to return the favor to guys who would like to do this work themselves. doing this stuff yourself succesfully yeilds great self satisfaction of a job well done. we did get off topic a bit. and am sorry for the inconvienece.

now back to topic. flow mods are a great way for a guy starting out that wants to learn. i wont get into timing cause its easy to mess up.

I agree ! I was just posting what the latest word "on the street" is for the thread. Was not trying to start a debate pro/con good / bad Just balh blah blah hoopla.. All good bud ! Reshaping the ports is a must anyways. I don't disagree fully they don't do anything at all... just not a power maker. Id say more of a "helper"
 
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Some of this comes from RCCA's Nitro Tuning Guide. The do some flow mods to a TRX 2.5 I think it was, have to dig up the book. They chart a noticeable increase in low end acceleration. Top end wasa the same, but it got there quicker. I'm not saying this is good or bad info. Its just a repudable source thats been read by many. May be the root of this.
 

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