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Old 06-29-2010, 10:51 AM   #1
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Default Longer Runtime

Hi, I would to know what should I do more to get better fuel mileage with my .28 engine (exactly it's SH .28 P8 engine).

So far i have done:

- gas cooler
- O.S. 2060 pipe
- some sleeve and crankshaft mods (ports enlarged and glass polished)

I have reached 8 minutes race runtime on mid-open track. I've heard that adding a shim under the head can help - is it true? What else can I do to get my runtime longer?
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Old 06-29-2010, 11:03 AM   #2
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Originally Posted by wiktor0410 View Post
Hi, I would to know what should I do more to get better fuel mileage with my .28 engine (exactly it's SH .28 P8 engine).

So far i have done:

- gas cooler
- O.S. 2060 pipe
- some sleeve and crankshaft mods (ports enlarged and glass polished)

I have reached 8 minutes race runtime on mid-open track. I've heard that adding a shim under the head can help - is it true? What else can I do to get my runtime longer?
Easy on the throttle. Be smooth. Dont flip over and that will save you.
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Old 06-29-2010, 11:10 AM   #3
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After modding this engine i suddelny stopped blipping throttle in the corners and opening full throttle after landing or while entering the main straight Wheels were milling for 10-15 meters and then car was accelerating right

So since that time I use only smooth throttle and fuel mileage went better.
I think that 8 minutes during race is not so bad runtime. Now, I fill up every 7:30, and before after 6 minutes
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Old 06-29-2010, 11:11 AM   #4
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#1, replace the piston/sleeve and whatever else was modded. Unless that kind of work is done by someone that really knows what they are doing it will almost result in poorer run time.

#2, change to 20% fuel. tuning will be easier and run times will be longer. You may not even notice the difference in power.

#3 Consider a .21 engine when it's time to replace the .28. With a decent .21 and a decent tune you will have more power and WAY longer run times. 11+ minutes is not uncommon with truggy tanks.
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Old 06-29-2010, 11:12 AM   #5
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It's a .28 so you can't expect great mileage. You can try a smaller carb venturi though.
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Old 06-29-2010, 11:19 AM   #6
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ok, thanks for any replies
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Old 06-29-2010, 11:29 AM   #7
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6 or 7 mm venturi will help alot.
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Old 06-29-2010, 11:54 AM   #8
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I run a Ninja JX21-B01A .21 engine with a Ninja EFRA2042 pipe - I am getting 12 minutes of runtime, and it is only getting around 96 degrees celcius, so I can push more out of it.

I am thinking of changing from OS P3 plugs to OS P4 plugs to see if that will give me even longer runtime. And I've got more than enough power, so I am even considering a 6.5 venturi instead of the 7.

I gotta get this baby above the 15 minutes of runtime
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Old 06-29-2010, 12:04 PM   #9
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I run a Ninja JX21-B01A .21 engine with a Ninja EFRA2042 pipe - I am getting 12 minutes of runtime, and it is only getting around 96 degrees celcius, so I can push more out of it.

I am thinking of changing from OS P3 plugs to OS P4 plugs to see if that will give me even longer runtime. And I've got more than enough power, so I am even considering a 6.5 venturi instead of the 7.

I gotta get this baby above the 15 minutes of runtime
Let us know when you hit the 15min. mark.
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Old 06-29-2010, 12:19 PM   #10
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get 100 ft of fuel tubing and wrap your car with it.
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Old 06-29-2010, 12:33 PM   #11
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Let us know when you hit the 15min. mark.
I actually read about a guy in Australia who constantly got over 16 minutes of runtime on his Ninja, so it is doable
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Old 06-29-2010, 01:01 PM   #12
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its a 28 your lucky to get 8 min. Get a .21
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Old 06-29-2010, 01:10 PM   #13
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i have also put a big fuel filter on mine and left the filter out of it, it holds alot of fuel!
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Old 06-29-2010, 02:50 PM   #14
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What you got to realise is, if the track is big (or fairly fast like over here in the EU). You won't have a hope in hell at getting 10mins. Drive smooth, regular clutch maintainence, no binding in transmission, .21 engine, tuned correctly and just drive the damn thing
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Old 06-30-2010, 05:49 AM   #15
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Quote:
Originally Posted by wiktor0410 View Post
Hi, I would to know what should I do more to get better fuel mileage with my .28 engine (exactly it's SH .28 P8 engine).

So far i have done:

- gas cooler
- O.S. 2060 pipe
- some sleeve and crankshaft mods (ports enlarged and glass polished)

I have reached 8 minutes race runtime on mid-open track. I've heard that adding a shim under the head can help - is it true? What else can I do to get my runtime longer?
One word: Sidewinder World Champion blend fuel!!!!!!!

Lots of folks have achieved significent run time improvement in addition to great engine life!

You might consider limiting throttle too - say 75% will make a BIG difference in run time without totally killing your power. My experiences with the smallest carb inserts is that they make the tune VERY hard to find; try staying with the 'medium' for your particluar engine, limit throttle and if you need fuel you should give the Sidewinder a whirl!

and noooooo, I don't work for Sidewinder; just a long time happy customer along with a lot of the drivers in the A Main at the off road fuel nationals last week.
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