Go-Tech Engines Thread
#421
Tech Addict
Joined: Dec 2006
Posts: 502
From: Surprise! No, really.
I have a 5port standard head, maybe switching to turbo head, and I run 30% fuel. Do I need to change/add/remove shims? Also, any tricks to replacing the head? It looks like you:
Remove the backplate, head, burn room, shims
Push out the sleeve with popsicle stick or toothbrush, NOTING DIRECTION
Pull rod off the crank with string and slide piston assembly out, NOTING DIRECTION
Remove G-clip, wristpin, and rod
Clean motor insides with a little fuel
Check bearings for grit/slop
Install new rod, new wristpin, and new G-clip
Apply some ARO to piston/sleeve/rod
Slide in piston assembly, push rod onto crank, noting direction
Slide in sleeve, noting direction
Turn over a few times to check smoothness
Install shims, turbo burn room, cooling head, screws, plug
Install Backplate
Any corrections?
Thanks
Travis
Remove the backplate, head, burn room, shims
Push out the sleeve with popsicle stick or toothbrush, NOTING DIRECTION
Pull rod off the crank with string and slide piston assembly out, NOTING DIRECTION
Remove G-clip, wristpin, and rod
Clean motor insides with a little fuel
Check bearings for grit/slop
Install new rod, new wristpin, and new G-clip
Apply some ARO to piston/sleeve/rod
Slide in piston assembly, push rod onto crank, noting direction
Slide in sleeve, noting direction
Turn over a few times to check smoothness
Install shims, turbo burn room, cooling head, screws, plug
Install Backplate
Any corrections?
Thanks
Travis
#422
AZTman sounds like you have everything covered. Only thing I do different is instead of a popsicle stick or a toothbrush, I usually place a zip tie in the exhaust port and then turn over the flywheel till the sleeve comes partially out. Then I take a screw driver and get under the sleeve flange and pry the sleeve out, (very very gently and be sure to work your way around the sleeve slowly.) Once it is high enough you can grab it with your fingers and pull it the rest of teh way out.
Be careful with the G-clips, theya re easy to lose
Remeber when installing the new rod, the skirt side of the piston faces the exhaust port and the cut side of the rod faces the opposite, towards the carb.
Be careful with the G-clips, theya re easy to lose

Remeber when installing the new rod, the skirt side of the piston faces the exhaust port and the cut side of the rod faces the opposite, towards the carb.
#423
got the 7 port and JP3 installed and broken in today:

I followed the directions on the race factor website and it seemed to work very well and was very easy. Once I got through all the break in tanks, I ran it around the yard for a tank...it's got a bog when I punch the throttle and idk if it's a lean or rich bog but I'm sure I can figure it out tomorrow when I take it to the track.
the only gripe I have is when the screw and sleeves that hold the carb fell out on the 5th tank...that was kind of lame lol

I followed the directions on the race factor website and it seemed to work very well and was very easy. Once I got through all the break in tanks, I ran it around the yard for a tank...it's got a bog when I punch the throttle and idk if it's a lean or rich bog but I'm sure I can figure it out tomorrow when I take it to the track.
the only gripe I have is when the screw and sleeves that hold the carb fell out on the 5th tank...that was kind of lame lol
#424
I followed the directions on the race factor website and it seemed to work very well and was very easy. Once I got through all the break in tanks, I ran it around the yard for a tank...it's got a bog when I punch the throttle and idk if it's a lean or rich bog but I'm sure I can figure it out tomorrow when I take it to the track.
Vise versa as well. If it stalls at first then runs strong you are too lean on the bottom. Lean on the bottom will also make the car seem as if it takes a while for the revs to come back down after letting off the throttle. (assuming the idle screw is set OK). Hope this helps. Make sure the motor runs over 200 degrees. If it never gets to 200, the top end needle is most likely too rich. You'll find that the top end needle has more overall effect on the engine temp when continuosly driving. If just putting around the yard or street it will be hard to get the temp up with putting a load on the motor.
#425
^you da man. I have been searching for a tuning description like that ever since I've gotten into the nitro scene. It sounds like both needles may be too rich. we'll see tomorrow!
I could tune my old motor fairly well but I didn't know any of what you just posted. lol. thanks a ton.
also, I used my temp gun during the whole process and kept it between 220 and 240 during the entire break-in.
I could tune my old motor fairly well but I didn't know any of what you just posted. lol. thanks a ton.
also, I used my temp gun during the whole process and kept it between 220 and 240 during the entire break-in.
#426
cool hope it helps, everyone has to learn. If you have any questions just PM me we'll see what we can figure out.
Also, as a "general rule" you want about a 1mm gap in the carb at idle. If you get lost in the bottom end tuning and cant figure out if the idle is off or bottom end setting is off, take the air filter off and set the idle gap to 1mm. That will let you know if a low or high idle is a faulty tune with the bottom end needle. Use calipers to find something that width, then you can slide it down the carb barrel until the gap closes or opens up to that tool. Then after the tune feels good slightly adjust the idle to where you like it, but you shouldnt have to go very far with the idle screw each way.
Also, as a "general rule" you want about a 1mm gap in the carb at idle. If you get lost in the bottom end tuning and cant figure out if the idle is off or bottom end setting is off, take the air filter off and set the idle gap to 1mm. That will let you know if a low or high idle is a faulty tune with the bottom end needle. Use calipers to find something that width, then you can slide it down the carb barrel until the gap closes or opens up to that tool. Then after the tune feels good slightly adjust the idle to where you like it, but you shouldnt have to go very far with the idle screw each way.
#428
got the 7 port and JP3 installed and broken in today:

I followed the directions on the race factor website and it seemed to work very well and was very easy. Once I got through all the break in tanks, I ran it around the yard for a tank...it's got a bog when I punch the throttle and idk if it's a lean or rich bog but I'm sure I can figure it out tomorrow when I take it to the track.
the only gripe I have is when the screw and sleeves that hold the carb fell out on the 5th tank...that was kind of lame lol

I followed the directions on the race factor website and it seemed to work very well and was very easy. Once I got through all the break in tanks, I ran it around the yard for a tank...it's got a bog when I punch the throttle and idk if it's a lean or rich bog but I'm sure I can figure it out tomorrow when I take it to the track.
the only gripe I have is when the screw and sleeves that hold the carb fell out on the 5th tank...that was kind of lame lol
#433
Swede its hard to say what stock needle settings are on that carb because there was a revision to the LSN. Its best set the idle gap then put the engine on the box and lean the HSN so it clears out on top, and then back it off 1-2 hours. then set the LSN on the box and clear out the engine by revving it. then listen for the engine to come down to idle fairly quickly and cout to 6 and then grab full throttle. you should richen the LSN until it has a slight bog before clearing out after the 6 second count. You will know its rich because you should see some fuel being spit out of the exhaust. After you do that set your idle and you should be close when you get on the track.
Dirtracer congratulations and thanks for giving the Go engines a chance, a properly set up 7port engine is very fast, the 7ports tend to be a little finicky in setup compared to the 5port. If you come from Novarossi engines like the p5 or p5x, then I would reccomend the 5port engine, if you come from a 7port like the werks b7, or the RB ws7 then get the 7port. I would also say the 7port is a little closer to a v-spec from the v-spec I drove for a couple laps.
Dirtracer congratulations and thanks for giving the Go engines a chance, a properly set up 7port engine is very fast, the 7ports tend to be a little finicky in setup compared to the 5port. If you come from Novarossi engines like the p5 or p5x, then I would reccomend the 5port engine, if you come from a 7port like the werks b7, or the RB ws7 then get the 7port. I would also say the 7port is a little closer to a v-spec from the v-spec I drove for a couple laps.
#434
the 7port looks good in that RC8...the only thing i noticed is that you are using zip ties for holding on the air filter, you may want to look into changing to orings, there has been alot of talk about the way the zip tie pinches the rubber and letting in fine dirt...
as I'm still a newb more or less...that's the first I've heard of using o-rings. how do you position them in/on the filter's tube?



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