Tuning by watching rod bearings

Why would you want to tune like that? If the bearing is smashed then you are detonating. Why not tune by reading the plugs. If you are detonating you are losing power.

 

Yes, detonation is not optimum combustion so you will lose some power based on how much detonation in how many cylinders.

 

Is this a frigging test? Hard photo to read but they look mixed. Down to the right looks close to being right but boy some of those look funny. How many runs on these plugs? Show me those plugs at Indy in person and I can tell you more. We also have beer.

Vic I have never squished a bearing on a run where the plugs look like the way I want them to and nothing broke. That is about 98 to 100% frosty with no heat past the first thread. Truthfully I don't see much difference in ET between 80% frosty and 100% frosty. Maybe a real small mph increase but that is not what wins races.

Now I don't want to piss anybody off but these are my thoughts. Be nice to me. I am not going to give away some of the secrets I have learned so I will keep it at a high level.
Tuning Roots blown methanol motor over the years hasn't changed much for some people and to me is pretty old fashion. I have observed some racers that do nothing but tear their motors up trying to run fast then there are guys that run faster and hardly ever tear up a motor. Having the bearings just barely smash all evenly just after the finishline means that the car was super lean right to the finishline and detonated just after the finishline right before shutdown. So now one knows what the tuneup was right at the end of the run and that is also applies to reading the plugs also. You can say that the cylinders are balanced but what about the AFR during the rest of the run. Most of the ET is gained in the 0 to 330 ft area and to me that is more important than 330 and on. 330 and on is all HP and gives you MPH and you are along for the ride. Just look at the boost in the first part of the run and you will see it is lower at specific RPMs than it is at the same RPM at the end of the run because of the ram air effect on the injector hat so maybe you don't need as much fuel down low as you think you do. So leaning it out at the end also leans it out in the first part of the run where the boost is lower and betters your 330 ft times and you final ET. So in my opinion some people think that super lean is good. I am not saying that you don't need to lean it out some during the second half because you do but no where near what is required to smash a bearing. The temperatture of that air in the manifold is increasing during the run and the Density Altitude inside that motor is going higher so less fuel is needed (don't confuse this with a screw blower tuneup). To get a stable constant AFR during a run takes some fuel control. The more constant the AFR the more power you are going to have the whole run. The hard thing is putting it all down on the track especially for a promod with a 4-Link.

 

A Roots blower creates lots of heat from the rotor seals rubbing against each other and against the case. As you progress through the run the temperature of the air in the manifold increases. This heat raises the Density Altitude and therefore needs less fuel to maintain the correct AFR

 

It was the ignition advance that was the cause of the increased power but the detonation was taking power away at the same time. This is why the nitrous guys are now spraying water into their engines to stop detonation and then they can advance the timing and make more power.

 

But would those bearings in a TF dragster be beat up because they can't take the 900 to 1000 HP push from each piston being slammed down the cylinder? Thanks, I have never seen plugs out of a TF motor. Wouldn't know how to read them or if there was any point in reading them.