RC Car Actions "How to port a Nitro Engine"
#729
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RE: RC Car Actions
I don't have any picturesof it yet. There is 2 more 3.3's to do then I can get to my own motors again.
Got a call from a guy today that I had done another 3.3 for and he told me that he got a run in with his 4tec and had a local cop clock him. He said it got 96 mph in about 200 ft but had to shut it down because there was only 300 of pavement next to a high school football field. He ended up crashing and breaking a few things so he didn't get another run or any video. I am sure that there will be a video sent real soon so I can post that for the nay sayers.
I have a couple cars that I've done up but run out of gearing options so they are too fast to even think about getting any traction. They would be more of a drag than a top speed.
Got a call from a guy today that I had done another 3.3 for and he told me that he got a run in with his 4tec and had a local cop clock him. He said it got 96 mph in about 200 ft but had to shut it down because there was only 300 of pavement next to a high school football field. He ended up crashing and breaking a few things so he didn't get another run or any video. I am sure that there will be a video sent real soon so I can post that for the nay sayers.
I have a couple cars that I've done up but run out of gearing options so they are too fast to even think about getting any traction. They would be more of a drag than a top speed.
#731
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RE: RC Car Actions
He didn't make the video yet. It was just him and the cop for that run. As a backup though I just bought a hpi racer 2. All I have are ofna cd3s and they don't have 100 mph gearing options. So of he doesn't send me one which he should because he calls me just about every day to talk. I can make my own vid when that shows up and I get it dialed in.
You know how it goes with some people since your a motor guy as well.
You know how it goes with some people since your a motor guy as well.
#732
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RE: RC Car Actions
Hi there, I finally did this port mod to my Hpi Nitrostar .25 - it really was not hard at all (well I'm very mechanically inclined lol). The reason why I did the port mod is because my clutch went out and since I had the motor out I decided to give it a shot. Who does not want some extra free power from their motor right? Well I am still waiting on my clutch parts to come (went with Max Life shoes and Mugen 1.0 springs) - I will come back and post my results once its on the road again!
#733
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RE: RC Car Actions
I got those pictures and updates from my guy in MO. He is 65 and his throat collapsed so he is in the hospital for now. My car is just about done in the mean time. There is a few issues to work out like the linkage, tap motor mounts, and play with some gearing but its coming.
There is more work done to the block and a couple other parts but this will get you enough of a gian to make you satisfied.
There is more work done to the block and a couple other parts but this will get you enough of a gian to make you satisfied.
#737
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Looks pretty Moby but also looks like a lot of material has been removed....two things happen...the crankcase volume increases and flow speed decreases...
#738
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very artistic...very clean work... ( I know whos that is ) .......However all that flash really will do nothing to make any more power........ Of course there could be timing changes in there to help power...but all the fancy flowwork on that sleeve is purely cosmetic.........Work sure looks clean
#741
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very artistic...very clean work... ( I know whos that is ) .......However all that flash really will do nothing to make any more power........ Of course there could be timing changes in there to help power...but all the fancy flowwork on that sleeve is purely cosmetic.........Work sure looks clean
Supertib
Not sure what your comment “I know whos that is), isabout, I do all of my own piston and liner mod”s, have for over 40years, On your statement “However all that flash really will donothing to make any more power”, and “ but all that fancy flowwork on that sleeve is purely cosmetic”, leads me to believe that Uhave never tried to fully modify a piston and sleeve for max power orU do not understand the basics of increasing maximum air and fuelinto the combustion chamber to increase horse power.
The 4 stroke V engines increase there air and fuel intakeby using larger valves on the intake and exhaust, which is the samething I do on the 2 stroke engines by enlarging the boost andtransfer port area and using radiused curves to increase highpressure flow into the boost and transfer ports, the 4 stroke Vengines also change the cam to increase intake and exhaust timingnumbers,”bring more fuel and air into the engine”,which is what Ido by changing the crank timing numbers. the boost,transfers,andexhaust numbers, in the 2 stroke engines, using my engine analysisprogram data.
I have included some basic engine numbers from the 3.3engine, also included at the bottom a quick look at recommended carbsize based on a rpm of 31000 and the same engine with RPM at 5000.
Date 03 21 2011
engine Traaxas 3.3serial # 321
practical RPM 31000
engine bore 0.665
engine stroke 0.578
rod length C to C 1.118
max rod angle 15.0
exhaust swept 0.428
exhaust duration 159.6
boost intake duration deg. 115.1
boost swept stroke total 0.522
transfer swept stroke tot. 0.501
head clearance in. 0.015
head volume cc 0.19
compression ratio 9.3
rotor open in.tol/top 0.587
rotor open degrees ATDC 216
rotor close in. tol/top 0.250
rotor close deg. ATDC 65
rotor duration degrees 209
timestudy @ 31000 RPM in seconds
exhaustexchange time 0.00086
intakeexchange time 0.00068
rotorexchange time 0.0113
optimalcarb size in. .321
timestudy @ 10000 RPM in seconds
exhausstexchange time 0.00266
intakeexchange time 0.00210
rotorexchange tiime 0.00349
optimalcarb size in. .210
#742
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sorry Moby but that sleeve is just goofy doodle cosmetic that does nothing to aid performance,.Unless your the person I think you are that is not your work...please post a few more pictures of your engines ?
FYI my name is Neal Smith, I own Clockwork Racing Engines..I Am a expert in maximizing the performance of these nitro engines and have been for many years now..... I also own a dyno and my own race track and I have my own race team, and under my guidance we have won 5 national offroad titles....
So n the end it is you who is mastaken on who knows what here.......Figured I should get you up t speed before you say anything else silly.......
FYI my name is Neal Smith, I own Clockwork Racing Engines..I Am a expert in maximizing the performance of these nitro engines and have been for many years now..... I also own a dyno and my own race track and I have my own race team, and under my guidance we have won 5 national offroad titles....
So n the end it is you who is mastaken on who knows what here.......Figured I should get you up t speed before you say anything else silly.......