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Old 06-07-2010, 07:18 PM   #2611
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Default motor master question?

Uriah,

I have a OS .28xz that is about 1 gallon old, I run dirt oval with it. I was having some issues with the engine on the top end sounding like it was rich, but I know it wasn't. I took it a part to take a look at it to see what might have been a problem. Well I found that the bottom of the exhaust port had a .012 deep by .220 chunk missing out of the edge closest to the piston. It had broken off (no scratches on the piston on the exhaust side).

The problem I have is when the piston is at TDC, I can put a flashlight into the back plate hole and see the light where the chunk is gone. Is this sleeve junk, is there any way to save it? If I raise the sleeve the .012 and lower the head clearance down the .012 how bad is the port timming going to be, or should I just buy another sleeve and start over again? Any help would be greatly appreciated.

Chad
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Old 06-07-2010, 09:50 PM   #2612
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Quote:
Originally Posted by Dynotech Racing View Post
Uriah,

I have a OS .28xz that is about 1 gallon old, I run dirt oval with it. I was having some issues with the engine on the top end sounding like it was rich, but I know it wasn't. I took it a part to take a look at it to see what might have been a problem. Well I found that the bottom of the exhaust port had a .012 deep by .220 chunk missing out of the edge closest to the piston. It had broken off (no scratches on the piston on the exhaust side).

The problem I have is when the piston is at TDC, I can put a flashlight into the back plate hole and see the light where the chunk is gone. Is this sleeve junk, is there any way to save it? If I raise the sleeve the .012 and lower the head clearance down the .012 how bad is the port timming going to be, or should I just buy another sleeve and start over again? Any help would be greatly appreciated.

Chad
He is on his way to the Nationals, talk to him a couple hours ago not sure if he has his laptop with him.
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Old 06-08-2010, 03:45 PM   #2613
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Thanks for the update, I'll wait....motor isn't going anywhere.
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Old 06-10-2010, 07:23 PM   #2614
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Default Murnan Modified Novarossi Flash .21 Full ceramic

Hello Mr. Murnan:

I just ordered for subject engine from your website.

I was hoping you could answer a few questions for me:

1) Since I also ordered for the break-in service, how long do you anticipate being able to ship this engine?
2) Can you provide details on how you break-in an engine? Do you replace the conrod after break-in (as some recommend)?
3) Are there any further steps that I need to take prior to leaning the engine and running it full tilt?

Really looking forward to trying your engine out.
Best Regards,
Mike Havlena
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Old 06-11-2010, 06:02 AM   #2615
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Quote:
Originally Posted by mhavlena View Post
Hello Mr. Murnan:

I just ordered for subject engine from your website.

I was hoping you could answer a few questions for me:

1) Since I also ordered for the break-in service, how long do you anticipate being able to ship this engine?
2) Can you provide details on how you break-in an engine? Do you replace the conrod after break-in (as some recommend)?
3) Are there any further steps that I need to take prior to leaning the engine and running it full tilt?

Really looking forward to trying your engine out.
Best Regards,
Mike Havlena
Hi Mike. The engine will be run in on the bench, and then in the car. I will run approximately one gallon of fuel through the engine to properly break it in. You will need to run a couple of fuel bottles through the engine before reaching a race tune. The rod does not need to be changed for a gallon of running after break in. I will have the engine ready to ship to you next week.
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Old 06-12-2010, 06:31 AM   #2616
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Default Hi

Hi. I would surely try to raise the liner. You have nothing
to lose. If you can seal the piston, and liner by shimming it up the engine should run ok. It will have more top end power that way. All of the ports are going to be open longer. I have done this with some engines to get more top end power out of them.

Quote:
Originally Posted by Dynotech Racing View Post
Uriah,

I have a OS .28xz that is about 1 gallon old, I run dirt oval with it. I was having some issues with the engine on the top end sounding like it was rich, but I know it wasn't. I took it a part to take a look at it to see what might have been a problem. Well I found that the bottom of the exhaust port had a .012 deep by .220 chunk missing out of the edge closest to the piston. It had broken off (no scratches on the piston on the exhaust side).

The problem I have is when the piston is at TDC, I can put a flashlight into the back plate hole and see the light where the chunk is gone. Is this sleeve junk, is there any way to save it? If I raise the sleeve the .012 and lower the head clearance down the .012 how bad is the port timming going to be, or should I just buy another sleeve and start over again? Any help would be greatly appreciated.

Chad
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Old 06-12-2010, 11:41 AM   #2617
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Thank you very much for the information, I will machine a shimm to raise it and try it out.

Chad
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Old 06-12-2010, 06:49 PM   #2618
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Default Munan Modified Novarossi Special .21 Full Ceramic

Would like to get everyone's opinion on this engine.

Does anyone have any experience running one?
Easy to tune?
Power?

Thanks
MH
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Old 06-20-2010, 06:01 PM   #2619
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So far the ET's have been hampered by weather, or crappy tracks. So far in the first 2 races our results have been good with one win, and one second. Mostly due to not getting to run the finals due to weather. I expect that at the better tracks there will be much better ET's. So far nothing below 1.6 something with the promod in competition. Practice is another story We need gobs of traction, and no rain to set fast ET's!!! So far that has not been the case. I hear that Rockingham is a great track though.
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Old 06-30-2010, 09:33 PM   #2620
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Quote:
Originally Posted by Grinder View Post
Hi Mike. The engine will be run in on the bench, and then in the car. I will run approximately one gallon of fuel through the engine to properly break it in. You will need to run a couple of fuel bottles through the engine before reaching a race tune. The rod does not need to be changed for a gallon of running after break in. I will have the engine ready to ship to you next week.
Hello Uriah!

I received the engine..thx very much.
I noticed that you have filled the engine with ..I guess after run oil...lots of it...I would assume that I would need to remove some of it prior to first start to avoid hydro lock?

Also, if you could provide your best recommendations for post race engine maintenance? some recommend the use of after run oil, if you agree, then which after run oil do you recommend?

Looking forward to your reply.
Regards,
MH
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Old 07-03-2010, 07:13 AM   #2621
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Quote:
Originally Posted by mhavlena View Post
Hello Uriah!

I received the engine..thx very much.
I noticed that you have filled the engine with ..I guess after run oil...lots of it...I would assume that I would need to remove some of it prior to first start to avoid hydro lock?

Also, if you could provide your best recommendations for post race engine maintenance? some recommend the use of after run oil, if you agree, then which after run oil do you recommend?

Looking forward to your reply.
Regards,
MH
Hi. I do put a lot of after run oil in the engines. It is a good idea to let the oil drain out if there is too much. There should not be so much to lock the engine. I will send you some of my after run oil. It is pretty good. I will also send that other INS box.
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Old 07-03-2010, 12:18 PM   #2622
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Okay guys here is the deal.. im currently running max power xxl3 non balanced and im just not impressed with motor. Now i have a new in box maxpower xxl3B balanced but im thinking its prolly not that much better then the non balanced motor. So im looking at maybe selling the max power stuff off and getting something new. here is what im thinking all murnan mods.

Nova 353
RBm3 tuned
RBm3 modified
or non mod flash

Now id like to really know how the rbm3 tuned version stack up against my max power motors? im really liking the idea of being able to get over 5 mins run time and never halfing to worry so much on run time. my max power will barley go 5mins. Im looking for something great on power and good life. give me your options ideas. i know in off road i had alot of bearing failures with RB but since we r in onroad im going to throw that aside. thanks in advance
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Old 07-03-2010, 12:25 PM   #2623
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Why not send the Max to Uriah to work over?
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Old 07-03-2010, 01:02 PM   #2624
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I have 3 JP Eagles and all 3 are different, the last one I did get seemed a bit underpowered until I changed gears, it did came to life.
Now I can messure up engines I noticed all 3 are different, not much but they are.

The balanced engine could have better choosen parts to run better because I do not believe MAX is bad. There is always a possibillity to have a less or on the other hand a very good performing engine.
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Old 07-05-2010, 05:20 PM   #2625
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Quote:
Originally Posted by Grinder View Post
Hi. I do put a lot of after run oil in the engines. It is a good idea to let the oil drain out if there is too much. There should not be so much to lock the engine. I will send you some of my after run oil. It is pretty good. I will also send that other INS box.
Thx a lot Uriah!!!
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