S bogs down at WOT

[GlamisSavageX]

Yesterday, I have made a number of tuning adjustments over the course of an hour and I can't seem to get it dialed in. Truck ran good before though. Under what circumstances will the S bog down at WOT. Too lean on the High Speed, I know, but what about low speed. Any tips?

 

[NissanDriver21]

Turn back the HSN 1/8th to get rid of the lean conditions..

Tuning in a Pinch
Many racers find it difficult to properly tune the low speed needle. We've developed a method that makes it easy, even for beginners, to adjust the low speed needle to within 5% of peak performance and it's done right on the bench. We call it the pinch test and here's how it works.

Step 1. Start your engine and warm it up for about 30 seconds by revving the engine from idle to mid-throttle while holding the wheels off the ground.

Step 2. Allow the engine to idle for 10 seconds. If the low speed needle tuning is so far off that it won't idle, simply bump the idle position higher until the engine will reliably run at a higher idle.

Step 3. With the engine at idle, pinch and hold the fuel line near the carburetor, cutting off the fuel flow and carefully listen to the engine rpm.

If the low speed needle is set correctly, the engine should increase rpm only slightly and then die.

If the engine increases several hundred rpm before dying, then the low speed needle is too rich and needs to be turned in.

If the rpm doesn't increase at all and the engine simply dies, the low speed needle is set too lean and should be richened or turned out.

After doing this a few times you'll get the hang of it, and tuning the low speed needle will become easy. The only way to get that last 5% performance on the low speed tune is through careful track testing. By evaluating the engine as it accelerates from a dead stop or out of slow corners during actual race conditions is the only way to get those last few percent of power from your engine. Variables like the clutch setting, gearing, traction, atmospheric conditions and even the car's weight will have an effect on this last 5% of tuning performance, and the optimum setting can only be reached by careful on-track tuning.

Courtesy of http://www.rchobbies.org/engine-tuning.htm

 

[GlamisSavageX]

thanks. I'll try that

 

[NissanDriver21]

Remember, if it's winter where you are and It's pretty cold out. You would want to run rich before you run lean, it will make performance a little on the weak side but It's better than a blown motor, as SJ put it out there for me..


Just pinch test the LSN and tune it accordingly.. tune back the HSN 1/8th turn to fatten it back up, and you should be alright..

 

[Jeremy]

Check these tuning vids out if you have High speed internet

https://www.hpisavageforum.com/forums/showthread.php?t=1955