markallen
RCTalk Addict
Which type of crankshaft is used for the Dynamite or XTM .21 conversions?Threaded or SG.
Thanks,
Mark
Thanks,
Mark
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.21 Conversion Help
- Thread starter markallen
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R/C Madman
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You can use either one but, if you are staying with the stock clutch setup you will have to cut either one you get down to make it fit.
jfischer
RCTalk Basher
What header off the engine
I want to put one of the OS21 RGX(P) engines in my 21 conversion and all the things I read says it needs a O.S. Exhaust Header .21 RG-BX which would be for a buggy and make it come out to the left side of the truck, rather then the right side, and you would have to use a pipe connected with a silicon coupler. What I want to use is the standard, or a .21 pipe that connects straight from the header to the pipe with springs, how most racing pipes are. I see you can get a O.S. Exhaust Adapter #5 .21 RG, Manufacturer Stock#
23626100 which would come out like a standard engine, then you could use this coupler to work, but I was wondering if the pull start on the O.S. .21 RG-X(P) is to tall and would hit it. I have the adapter #5 ordered along with the engine now, and hope the combo will work. I know it might sound weird but am just looking for a low powered big block, something simple and easy to run, and wish there was something you could use a Roto Start, or other such but I am pretty sure with most all of the engines the back shock tower is going to get in the way, (I am running the Gorilla-Maxx towers) but even the stock ones would do the same thing.
Any help, or ideas on the header, or if it will work would be appreciated.
I want to put one of the OS21 RGX(P) engines in my 21 conversion and all the things I read says it needs a O.S. Exhaust Header .21 RG-BX which would be for a buggy and make it come out to the left side of the truck, rather then the right side, and you would have to use a pipe connected with a silicon coupler. What I want to use is the standard, or a .21 pipe that connects straight from the header to the pipe with springs, how most racing pipes are. I see you can get a O.S. Exhaust Adapter #5 .21 RG, Manufacturer Stock#
23626100 which would come out like a standard engine, then you could use this coupler to work, but I was wondering if the pull start on the O.S. .21 RG-X(P) is to tall and would hit it. I have the adapter #5 ordered along with the engine now, and hope the combo will work. I know it might sound weird but am just looking for a low powered big block, something simple and easy to run, and wish there was something you could use a Roto Start, or other such but I am pretty sure with most all of the engines the back shock tower is going to get in the way, (I am running the Gorilla-Maxx towers) but even the stock ones would do the same thing.
Any help, or ideas on the header, or if it will work would be appreciated.
bomber said:
I had the same set up. New era makes an OS 21 RG header adapter. With the XTM kit's header and exhaust, you need the adapter. I had to dremel mine to get it to fit past the pullstart housing. I'm pretty sure Bomber did as well. I also dremeled the fins on the header from the XTM to get it to fit. He bought his 21 off ebay and the header that came with it didn't have fins like the current kit's header does.
To be honest, I think he used a new era adapter and I got lucky and one came in the box with my engine.
My LHS at the time was so busy screwing me over that he handed me the wrong engine. The engine he gave me didn't have a carb and was a non-pull start, but had the adapter that OS puts in. I pocketed the adapter (it was under the foam lining) and took the engine back all pissed off to get the correct one with a carb and pull start. They over charged me for that engine ($170), which is why I pocketed the stupid adapter.
Your correct about the shocks hitting the header. Bomber has some nice dents in his header from it and I actually punctured my header. I changed over to a 4 supermaxx shock setup which proved to be better, but I still dented my header on crappy ass ended landings.
I've since bought a savage and gave up on the dream of a 21 maxx. Just way to much $ and time for a crappy end result. Now the maxx is in pieces and I use parts off it for my little 18 maxx that I bash.
To be honest, I think he used a new era adapter and I got lucky and one came in the box with my engine.
My LHS at the time was so busy screwing me over that he handed me the wrong engine. The engine he gave me didn't have a carb and was a non-pull start, but had the adapter that OS puts in. I pocketed the adapter (it was under the foam lining) and took the engine back all pissed off to get the correct one with a carb and pull start. They over charged me for that engine ($170), which is why I pocketed the stupid adapter.
Your correct about the shocks hitting the header. Bomber has some nice dents in his header from it and I actually punctured my header. I changed over to a 4 supermaxx shock setup which proved to be better, but I still dented my header on crappy ass ended landings.
I've since bought a savage and gave up on the dream of a 21 maxx. Just way to much $ and time for a crappy end result. Now the maxx is in pieces and I use parts off it for my little 18 maxx that I bash.
jfischer
RCTalk Basher
Header info
Thanks for the info, I went ahead and ordered the adapter that is suppose to fit the standard RG engine and like you said, you have to cut some away from it to get it to fit, and I kind of thought that. I hate pull starts and wish I could use a starter box on it, or from what I have seen I think one of the Sullivan Tiger drives might fit it then I can just use the Drill to start it, have to see how all fits I guess.
I would go with something else, if I raced offroad, but I race onroad racing only with this truck so all is setup with limiters in shocks, very little ground clearance, different shock towers, where the shocks are laid down a lot in the rear, so I think the header should fit ok, there is a lot of room back there now, and everything else in the truck is pretty much bulletproof and I have tons of parts for both it and E-Maxx trucks I have raced.
I have a buddy that runs a Savage that races with me and it is tied down, super short hard springs on it, and I drove it a week or so ago and it is planted like a car, so see why he is beating me, and the course is more technical so don't need tons of top end, more bottom end to help through about 8 S turns in the middle and figure the plain old simple motor would work. I have stuck the money in the Sirio, Picco and others and found many times you just seem to be wasting your money, since alls I do is race this truck,(not a basher) so it only see life about once a week.
Maybe it will get here by the middle of Thursday or so of this week, and see if all is going to fit after doing some cutting on the fins on the header that comes with the kit (I kind of thought that by looking at it) and I can make it last for the end of Summer season, as we are running the last date this weekend in second place now, and they drop your 2 lowest scores so I can't come up any.
But from what you have said, the RGX(P) should work in the truck with some small mods. Oh, you get all kinds of different info on things, are the threads on the end of the crank ASA or metric, as from what I read I thought it said they were 1/4" 28 I think and the nut needed to hold the flywheel on I know is metric now, as most engines are, (but never can tell with OS)
Thanks for all your help and hope to get the thing in and running this week.
OH, I had a P2, the Mid block style Picco that I put in and only got about 2 gallons through that engine tons of problems with it, basically think it was the backing plate and sucking air throgh where the rod comes through for the starter, and they sent me a new one, knowing the first ones had problems, but it was sure sucking air from some place the last few weeks and leaning it out. Temps wern't that bad at the end of the race 280 or so, but after I took the engine apart I could see where it lost so much power when it got hot, and this is the first real engine I have trashed, so tell folks to stay away from that and either stay with the small block, or go real big block to stay away from problems.
Wish me luck with the OS, I will clean the insides up a bit and hope it lasts the Fall season.
Thanks for the info, I went ahead and ordered the adapter that is suppose to fit the standard RG engine and like you said, you have to cut some away from it to get it to fit, and I kind of thought that. I hate pull starts and wish I could use a starter box on it, or from what I have seen I think one of the Sullivan Tiger drives might fit it then I can just use the Drill to start it, have to see how all fits I guess.
I would go with something else, if I raced offroad, but I race onroad racing only with this truck so all is setup with limiters in shocks, very little ground clearance, different shock towers, where the shocks are laid down a lot in the rear, so I think the header should fit ok, there is a lot of room back there now, and everything else in the truck is pretty much bulletproof and I have tons of parts for both it and E-Maxx trucks I have raced.
I have a buddy that runs a Savage that races with me and it is tied down, super short hard springs on it, and I drove it a week or so ago and it is planted like a car, so see why he is beating me, and the course is more technical so don't need tons of top end, more bottom end to help through about 8 S turns in the middle and figure the plain old simple motor would work. I have stuck the money in the Sirio, Picco and others and found many times you just seem to be wasting your money, since alls I do is race this truck,(not a basher) so it only see life about once a week.
Maybe it will get here by the middle of Thursday or so of this week, and see if all is going to fit after doing some cutting on the fins on the header that comes with the kit (I kind of thought that by looking at it) and I can make it last for the end of Summer season, as we are running the last date this weekend in second place now, and they drop your 2 lowest scores so I can't come up any.
But from what you have said, the RGX(P) should work in the truck with some small mods. Oh, you get all kinds of different info on things, are the threads on the end of the crank ASA or metric, as from what I read I thought it said they were 1/4" 28 I think and the nut needed to hold the flywheel on I know is metric now, as most engines are, (but never can tell with OS)
Thanks for all your help and hope to get the thing in and running this week.
OH, I had a P2, the Mid block style Picco that I put in and only got about 2 gallons through that engine tons of problems with it, basically think it was the backing plate and sucking air throgh where the rod comes through for the starter, and they sent me a new one, knowing the first ones had problems, but it was sure sucking air from some place the last few weeks and leaning it out. Temps wern't that bad at the end of the race 280 or so, but after I took the engine apart I could see where it lost so much power when it got hot, and this is the first real engine I have trashed, so tell folks to stay away from that and either stay with the small block, or go real big block to stay away from problems.
Wish me luck with the OS, I will clean the insides up a bit and hope it lasts the Fall season.
Unfortunatly, bomber nor I had good experiances with the OS 21 RG. I busted a crank shaft and he broke 2 con-rods. All 3 engines had just over a gallon or so run through them. The engine made ok power, but nothing too outrageous.
I took my engine, pulled out the pieces of the crank and replaced it with one of his that he had after his engines broke. I put it together and threw it in a box in case either one of us needs an engine down the line just to get us by for the day.
I'm currently running an Omega 21 Comp and he's running a HB Powerhouse 26. (I think it's HB anyway). I have a little over 2 gallons through mine and it still has quite a bit of pinch at TDC. I don't think he has a gallon through his yet though.
I took my engine, pulled out the pieces of the crank and replaced it with one of his that he had after his engines broke. I put it together and threw it in a box in case either one of us needs an engine down the line just to get us by for the day.
I'm currently running an Omega 21 Comp and he's running a HB Powerhouse 26. (I think it's HB anyway). I have a little over 2 gallons through mine and it still has quite a bit of pinch at TDC. I don't think he has a gallon through his yet though.
jfischer
RCTalk Basher
OS cranks
I have heard of a few that have had the cranks and rods break on the OS engines, and most that like them and know them say break-in is pretty critical on them. I guess I will find out as I will do my standard method as I have always had good luck with it on engines.
Were you running the trucks off-road or on-road?
I have heard of a few that have had the cranks and rods break on the OS engines, and most that like them and know them say break-in is pretty critical on them. I guess I will find out as I will do my standard method as I have always had good luck with it on engines.
Were you running the trucks off-road or on-road?
olds97_lss said:
Primarily off. Bomber likes to wind his out in a long straight and take big air. I'm more of a pokey climber. I do a lot of jumping, but WOT passes aren't what I do too often.
We both pretty much broke in using the heat cycling method. In between tanks, we made sure to put the piston at BDC.
It was really the only engine I've ever had longevity problems with. My first truck was a xxx-nt RTR which came with a Dynamite Mach 15. I didn't break it in properly (first truck, first engine) and it lasted me about 4 gallons before it died. I then put in an OS 15 cv-r(x) and ran 6 gallons through it before I traded it off. The person I traded it too has run about 1.5 gallons through it since.
Then I got the maxx 2.5. I think I had a bumb engine or lack of patience or both... I gave up on that one before I ran a gallon through it. I then ran the OS 21 RG in my maxx. I think I may have ran a little over 2 gallons through it before the crank snapped.
Like I said, I gave up on the 21 maxx and dropped it back down to orig maxx but installed an orion wasp 18 in it. I have about 3 gallons through that engine now. It doesn't have shite for compression, but it never really did. Even during break-in it was easy to turn over. It still fires right up and runs with temps under 260.
We both pretty much broke in using the heat cycling method. In between tanks, we made sure to put the piston at BDC.
It was really the only engine I've ever had longevity problems with. My first truck was a xxx-nt RTR which came with a Dynamite Mach 15. I didn't break it in properly (first truck, first engine) and it lasted me about 4 gallons before it died. I then put in an OS 15 cv-r(x) and ran 6 gallons through it before I traded it off. The person I traded it too has run about 1.5 gallons through it since.
Then I got the maxx 2.5. I think I had a bumb engine or lack of patience or both... I gave up on that one before I ran a gallon through it. I then ran the OS 21 RG in my maxx. I think I may have ran a little over 2 gallons through it before the crank snapped.
Like I said, I gave up on the 21 maxx and dropped it back down to orig maxx but installed an orion wasp 18 in it. I have about 3 gallons through that engine now. It doesn't have shite for compression, but it never really did. Even during break-in it was easy to turn over. It still fires right up and runs with temps under 260.