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Old 12-25-2006, 07:36 AM   #16
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BUT THE CRANKSHAFT I HAVE IT IN, SHOULD BE ALRIGHT FOR NOW AND JUST START USING RTV ON OTHERS.. THANKS AGAIN
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Old 12-25-2006, 08:32 AM   #17
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Quote:
Originally Posted by stefan
The REAL problem with JB (epoxy) is that it's not alcohol (methanol) resistant.

It will soften and eventually loose adhesion, so better go with the RTV.
Stefan is correct. It will eventually come apart. Use RTV.
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Old 12-25-2006, 12:55 PM   #18
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Quote:
Originally Posted by Grinder
Stefan is correct. It will eventually come apart. Use RTV.
THANKS GRINDER :
WHAT RTV DO YOU USE, A FRIEND OF MINE HAS A TZ.12 MODDED BY YOU AND YOUR RED PUTTY LOOKS PERFECT, DO YOU USE FLOWABLE RTV BECAUSE IT LOOKED LEVELED OUT, AND LIKE GLASS..
DONT WORRY GRINDER I AM NOT TRYING TO BOOTLEG YOUR ANY OF YOUR WORK, JUST FOR MY PERSONAL USE..
I WANNA SEND YOU MY JP PLUS 12 3T SO YOU CAN PUT BEARINGS IN THE FRONT AND REAR ..
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Old 12-26-2006, 07:47 PM   #19
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I use ThreeBond 1211 silicone liquid gasket. It flows out perfectly and bonds to the surface extremely well. It takes a couple days to set, but you won't be disapointed. You can buy it from places that service atv's and watercraft. Hope this helps.

Keith
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Old 12-26-2006, 09:45 PM   #20
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I JUST ORDERED SOME GE RTV112 WE WILL SEE HOW THIS STUFF FLOWS OUT AND BONDS I WILL POST PICS AS SOON AS I GET IT SET..
WHERE CAN I FIND THREE BOND 1211
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Old 12-31-2006, 08:37 PM   #21
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Sorry to I have ask but what purpose does putting the putty in the crank shaft?
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Old 01-01-2007, 03:23 AM   #22
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Quote:
Originally Posted by bvoltz
Sorry to I have ask but what purpose does putting the putty in the crank shaft?
Good modified engines have a hollowed crank shaft for weight reasons and the putty fills the hole.

A lot of backyard tuners put it in as a selling argument
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Old 01-01-2007, 03:42 AM   #23
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Hello Guys, The red Polumer in cranks dose 2 things first is it fills the void form when the crank is over boared to lighten in for max rpms but it is not just to fill the gap left behind. It moves in and out as the crank turns creating crank case preshure and creating a vortex through the crank center kind of like when you pull the plug from the sink. It works like a pump bosting crank case preshure ther for increaseing the air fuel mixture and wile also increaseing preshure inside the engine. Rember Guys if you have this pudy in your crank never use any kind of spray cleaner it reacts with the polumer and makes in debond from the steel ending up with you looking for ways to replace it rtv sealent looks ok but it dose not have the same properties as the polemer and most are not fuel and oil restant witch means it will part from the crank after a wile. Hope this helped Regards Jeremy.
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Old 01-01-2007, 03:47 AM   #24
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It also has almost no efect on the cranks blance as its so close to the center its not an prob. Regards Jeremy.
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Old 01-01-2007, 09:46 AM   #25
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i tried the threebond 1211 and seems to bond great but just takes to long too cure, and also tried the ge rtv112 and i think flows better and cures faster so i think if you wanna wait get the threebond "and i is not hard to find" or the ge "hard to find"
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Old 01-01-2007, 11:43 AM   #26
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Many thanks for the detail to the purpose of the putty...
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Old 01-01-2007, 12:35 PM   #27
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I have used the Threebond 1211 for some many years now, and it works very well. If you are too impatient to let it cure naturally, a small amount of heat will accelerate the curing process. Such as a hot plate on lowest setting, heat gun, or simply letting it rest in the sun on a warm day. 150deg F seems to work well but I wouldn't go much hotter than that.

As for the theory behind the mystery putty itself, the reason for it's placement is two fold. One, it is there to fill the void left by the machining process in crankshaft manufacture, thus straightening the pathway from the carb to the crankcase. And two, it acts as a crankcase stuffer. By occupying area in the crankcase it raises the primary compression slightly. This can be a good thing sometimes and also a bad thing depending on the engine design and intention of modified engine power delivery.

However, I have done a little research with crankshafts on the dyno and I have yet to see any change in power from any engine both with and without the magic putty in place or not. You are much better off altering the crank's intake timing to see differences in power.

This mod is definitely more show than go! Surely a selling point to people investing in trick or modified engines. On the other hand, I really can't see any harm in doing this to an engine as long as you use a material that is engine safe (won't cause damage to the engine if it comes loose and goes through the engine).

BK
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Old 01-01-2007, 02:22 PM   #28
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Mxwrench:

I have had alot of novarossi engines and also the Recab and standard OS engines.

I have messured the timing on my first P5 that came out ( the engine that came with the large crank*) and the later one with the stuffed crank. I have meeured carnk timings and they are identilcal. The crankshaft with red putty has moore bottom end and slightly better fuelconsumption. I did not belive this and thought it was becaus it was two differetn engines. As a test i ran the first P5 engine and tuned for max performance. I took the engine out of the car and took out the crank and put in the crank with red paste. I was then convinced that it actually was the case. Crankshaft with red paste has moore bottom end and a little better fuel milage. It was moore difficult to drive and also i had moore wheelspinn out if the corner. Only thing changed was the crank, evything else was the same.

I friend of mine ( norwegian national winner) and best ranked Norwegian driver did run standard OS engines. I convinced him to try the Recab team version and he was in no doubt that the Recab engine had moore bottomend, better fuelconsuption and he also claimed it had higher top speed. Teh only difference between the standard OS and the Recab Team is lightend an red putty in the crank. Speed has actually been messured with a lazer gun under the Norwegian champs and a Norwegian cup race at the same treck under same conditions. Smae car, gearing fuel outside temp and so on. Recab made 3 km/h moore top speed.

If it is if the crankshaft is lighter or the red putty i do not know, but i support the thery that it makes a "pump effect" in the crank.

I now that the dyno should show it but i am not convinced that it is acurate enough for this.

Happy new year!!
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Old 01-01-2007, 03:54 PM   #29
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Quote:
Originally Posted by am
Mxwrench:

I have had alot of novarossi engines and also the Recab and standard OS engines.

I have messured the timing on my first P5 that came out ( the engine that came with the large crank*) and the later one with the stuffed crank. I have meeured carnk timings and they are identilcal. The crankshaft with red putty has moore bottom end and slightly better fuelconsumption. I did not belive this and thought it was becaus it was two differetn engines. As a test i ran the first P5 engine and tuned for max performance. I took the engine out of the car and took out the crank and put in the crank with red paste. I was then convinced that it actually was the case. Crankshaft with red paste has moore bottom end and a little better fuel milage. It was moore difficult to drive and also i had moore wheelspinn out if the corner. Only thing changed was the crank, evything else was the same.

I friend of mine ( norwegian national winner) and best ranked Norwegian driver did run standard OS engines. I convinced him to try the Recab team version and he was in no doubt that the Recab engine had moore bottomend, better fuelconsuption and he also claimed it had higher top speed. Teh only difference between the standard OS and the Recab Team is lightend an red putty in the crank. Speed has actually been messured with a lazer gun under the Norwegian champs and a Norwegian cup race at the same treck under same conditions. Smae car, gearing fuel outside temp and so on. Recab made 3 km/h moore top speed.

If it is if the crankshaft is lighter or the red putty i do not know, but i support the thery that it makes a "pump effect" in the crank.

I now that the dyno should show it but i am not convinced that it is acurate enough for this.

Happy new year!!
AM,

The lighter crankshaft you are describing should provide you with the results you speak of (Better fuel consumption, and more bottom power, and less driveability). Yes the putty does increase pumping effect slightly, but not because of the reasons described previously in this thread. The increased pumping effect is simply caused by the increased primary compression when putty is added to the crank, thus lowering the crankcase air volume capacity.

One thing that the dyno will not show us (at least not as of yet), is fuel consumption. Possibly in the future though. But as for the accuracy, I made runs with the same engine, and same carb settings, both with and without the putty and each run overlayed on top of eachother within .01 hp.

Now changing crankshaft balance or mass will definitly show on the dyno, as it has in previous testing also.

Wether you are convinced of the accuracy of my dyno or not is really no concern to me. What is important is that the engine manufacturers that are using it for development are convinced and are having good results. And this seems to be the case.

I wish you and your family a happy new year as well!

BK
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Old 01-02-2007, 11:19 PM   #30
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WELL THE CRANK RAMP DOES MAKE A DIFFERENCE MODDED A OS TZ12 THIS WEEKEND AND HAS TONS OF MORE BOTTOM END ....
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