[MT BUICKNUT]

Finally got the engine back together and made the weekend race. Car performed really well. Its a Flying Toilet system and works well. The motor is a 470 Buick 12.6:1. This weekend the temps were in the 70's, starting temp on the motor was around 140* it gained temp at the end of the pass like it should. I lean it out on the return and by the time im back in the pit I'm 180+ and oil is around 140+. Plugs look pretty good and clean. Is this a pretty normal temp rise? The motor is at 36* timing, should it have more timing or more fuel also. I never had it build this kind of heat before. Prior to this it was 10.3:1 motor never ran the fan ever only the pump. Just wondering if I need to change something.
Thanks Rick

 

[oldvintageiron]

You might fatten her up till it slows down. I'd start a little hotter then 140. It does seem a bit in the lean side.

Is that the same tune form the 10.8?

 

[MT BUICKNUT]

No, the tune on the 10.3 was WAY to fat. Apparently that tune was for sea level, not 4500+ where I run. It was a larger mains 36 and fatter pill 88. Not it has a 35 mains and 100 pill. I thought about either adding more fuel or some more timing. The plugs look like it could use some more timing. Seeing how it was building heat so easy I thought it could use one or the other if not both. The car was repeating on the et so I didn't want to change anything at that time.
Thanks Rick

 

[us7race]

Do you have EGT on it? Sounds a little lean. I'd go up 4 numbers on your bypass at a time and see where you end up. Go from the 100 to a 96 ect. Barrell valve cam play a part in the temp too on the return road and idle time. Good luck!

 

[RT67Camaro]

What are your water temps back in the pits if you don't lean it out on the return road? I roll through the water box at 160 and finish back in the pits at 180 -190 depending on summer vs. spring/fall temps. Water temp around 180 isn't bad. You certainly want it hot enough to prevent condensation and alky milked oil. Before I ran a vacuum pump I would make sure it was 180+ when I loaded it in trailer and then pulled the breathers out to let moisture evaporate.

 

[tempname]

You are leaning it out, so that is normal, and you are doing a good thing for sure. If it comes up on the converter quick and clean, you can't be too wacked on your barrel valve setting. And if it is going down the track well, the main pill probably isn't goofy either. I would, as I am sure you will, try different pills to get the best 330' times and be happy with the pill. If it comes up on the converter all times and temperatures, then lock down your throttle body air setting and never touch it again. Make a note of your idle rpm warmed up, and keep that the same forever as well. What you will change is your bv when you make pill changes. But that is easy now. You simply make the pill change, start it up and get it warm, and adjust the bv so you have the same rpm you always had. That means you have the same mixture you always had. Done.

 

[MT BUICKNUT]

Not sure what it would do on the return road I have always leaned it out. Always tried to get the temp up to get rid of the water and meth out of the oil. I did lean out the barrel valve at idle, it was pretty rich at idle. I will try changing pills and put some more fuel in it this weekend and see how it reacts.
Thanks Rick

 

[tempname]

Just remember that it has to be somewhat rich at idle. ME has no accelerator pump, so it needs to be rich right at the hit.

 

[MT BUICKNUT]

Tempname
What you are saying makes a lot sense. It comes up on the convertor, the car performed well this weekend. I just never had it make heat like it did. Of course the original tune was way off, so that might be why. So if you put more fuel in it then you would have to lean the barrel out to get the idle back? I wouldn't think that 4 sizes would make that much of a difference in the idle???
Thanks Rick

 

[stuska1]

Jet it so it MPH's best , Put more fuel in it, if it slows down take fuel out of it until it slows down.

Set the idle mixture rich enough it won't bogg. You can lean it out at idle if you have problems keeping heat in it. You can also use your fuel shut off to temporarily lean it out, just pull the shut off open a little.

 

[tempname]

Don't change your bv to accommodate heating the motor. That bv is for getting up on the converter. Use the fuel shutoff like you are to lean it up around the pits.
In answer to your question: Yes. If you richen the main pill, you will find yourself leaning up the bv to achieve the same idle rpm. As long as you never change your butterfly setting, this will work every time. If your pill size for best mph is leaner than the pill for best 330, stick with the 330 pill, and add a high speed lean out to the system when you feel comfortable with doing so. It won't gain you a lot, but you may pick up a little mph.

 

[NHRA686]

Rule of thumb is 10 deg temp rise from start to finish line in 1/4 mile. You need to set your barrel valve from lean to when it doesn't stumble when you whack it. (whack test). Read your plugs to find high RPM tune. A new cad plated plug should have 1/2-3/4 of plateing burned off of top ring, where ground strap is, in one pass. Acheive that, and you are tuned up!