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-   -   Greetings from Germany and ask (https://www.nopistons.com/rotary-engine-building-porting-swaps-55/greetings-germany-ask-75141/)

mrlowbudget 01-20-2011 11:40 AM

Hi I'm Thomas and I live in the north of Germany. There are almost no Rotary Dragster and therefore we are still very inexperienced. I have a VW rabbit www.rotorrabbit.com built and have some questions.

Maybe someone can give helpful with tips. Some of this I may already know and am very grateful to them.

I wonder how much exhaust gas temperature is normal if a 13B is running at idle? And can anyone tell exactly when the exhaust port must be signed no later than at a larger exhaust port?

many thanks thomas

Judge Ito 01-28-2011 02:00 PM


Originally Posted by mrlowbudget (Post 845960)
Hi I'm Thomas and I live in the north of Germany. There are almost no Rotary Dragster and therefore we are still very inexperienced. I have a VW rabbit www.rotorrabbit.com built and have some questions.

Maybe someone can give helpful with tips. Some of this I may already know and am very grateful to them.

I wonder how much exhaust gas temperature is normal if a 13B is running at idle? And can anyone tell exactly when the exhaust port must be signed no later than at a larger exhaust port?

many thanks thomas

thomas the problem we are having with your question is the way your wording it. I know ur german, but I'm not understand all of both your questions. first questions is the egt's? and second question?

mrlowbudget 02-07-2011 02:58 PM


Originally Posted by Judge Ito (Post 846212)
thomas the problem we are having with your question is the way your wording it. I know ur german, but I'm not understand all of both your questions. first questions is the egt's? and second question?

The problem is that you not answered my email I've you've sent a photo. sorry but this is such a Google translation tool German-English

Judge Ito 02-12-2011 07:05 AM


Originally Posted by mrlowbudget (Post 846448)
The problem is that you not answered my email I've you've sent a photo. sorry but this is such a Google translation tool German-English

I did not get the picture thomas. re-send the picture.

mrlowbudget 02-13-2011 12:47 PM


Originally Posted by Judge Ito (Post 846584)
I did not get the picture thomas. re-send the picture.

Hi I'll have another 2 emails sent.

Lynn E. Hanover 04-08-2011 10:34 AM


Originally Posted by mrlowbudget (Post 845960)
Hi I'm Thomas and I live in the north of Germany. There are almost no Rotary Dragster and therefore we are still very inexperienced. I have a VW rabbit www.rotorrabbit.com built and have some questions.

Maybe someone can give helpful with tips. Some of this I may already know and am very grateful to them.

I wonder how much exhaust gas temperature is normal if a 13B is running at idle? And can anyone tell exactly when the exhaust port must be signed no later than at a larger exhaust port?

many thanks thomas





The Exhaust Gas Temperature at idle is of no importance. So little fuel is being burned that a standard EGT gage probably will read nothing. The EGT gage is used to tune at a loaded wide open throttle setting. I used a movie camera to watch the gages since they move quickly with RPM changes. Here is one method to test mixture strength

at various RPM.



Warm the engine to normal temps. Write the test data on a clip board so you know that you will test at 5,000 RPM and again at 6,000 RPM on this pass. Just find a straight road where few cars travel. Run up to 5,500 RPM in say 3rd gear.

Hold that RPM with left foot braking while the throttle is held wide open. Read and record the EGT. This is the same as tuning on a dyno. Let the engine cool a bit and go again at 6,000 RPM.



You are looking for 1600 degrees on the EGT. Too lean will be hotter. Too rich will be cooler. This is about 12.6:1 on the fuel air gage or oxygen sensor. Use a three wire or heated sensor. This will put you just rich of best power, and give you a strong long lasting engine. That last few HP is there but engine life will be short. So stay at 1600 or even a bit less.



Lynn E. Hanover


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