Don Terrill’s Speed-Talk

Beyond some break-in protection, I have never read anything from the scientific articles that says that moly additives solve the high pressure, long term wear challenges for cam lobes and lifters. It is all related to ZDDP levels. So, I am very doubtful that adding moly to your oil for flat tappet p...

Don't know about their current philosophy, but in the carburetor days most OEMs found it pretty much a wash power-wise and better for fuel economy to run the CR on the high side and back out the WOT spark as necessary. That way they could use optimum part throttle spark while taking advantage of th...

bigblockmopar wrote: ↑Sun Apr 28, 2019 4:11 pm 11.3:1cr on a daily driven 360ci smallblock Mopar.
CompCams XE256.
Propane GAS

LOL.. that's cheating with the propane!

According to the chart on page 12 the oil rings transfer more heat than any other ring. I don't quite understand how because the oil ring rails, when considering surface area, have the least contact area of the other 2 rings. And after reading all the posts how can top 2 rings transfer/dissipate he...

FWIW, dynamic compression ratio was known and used long before the 70's. But you are correct about the cams.... it was not the loss of lead as much as being triggered in the early 70's when the Arab oil embargo hit; prices doubled overnight and fuel availability was pretty sketchy for 6-8 months. Si...

Ran across this while looking at some other stuff today... it shows the heat transfer from piston being by far due to the top rings. That is pretty interesting IMHO. Look at page 12 of thisl ink; it shows 70% of piston heat going out of the ring/land area. This is from a diesel engine, but I would n...

Nm9 noted the hone marks being more worn at the top of the bore,these are not high spots, they are where the ring is forced into the bore by initial combustion,this can get quite pronounced in old engines Yes I know what you are speaking about, but as Modok noted, that is not what I was referring t...

Torque plates have been mentioned. But for more mundane engines bored/honed without them, there are going to be cylinder distortions when assembled that presumably need to be worn down. So the idea that all break-in processes are 'instant' in those cases does not seem likely, and some extended break...

FWIW.. for some higher HP factory snowmobile engines (3 HP per ci), the coating is not part of the clearance.

Depends on who you buy them from and what spring package you get from them. Buying EQ's as complete heads appear to be completed at the seller's shop. (It's not like the Edelbrocks where the manufacturer supplies a specific spring package depending on the lifter type, or as bare heads.)

Hey OP, If this is a standard Mopar electronic ignition from the 70's, the you have 2 possibilities: 4 prong module: Uses the single section OEM ballast in series with the coil, between the 12V source and the coil +. That ballast is the 0.5-0.6 ohms cold and around 2 ohms hot. 5 prong module: Uses t...

Hold it.... needs some more info here. 1. Yes, the resistances will add in series BUT, the hot resistances are not guaranteed to equalize when they warm up. 90+% of thr time, one resistor will heat up faster and 'hog' the heating power and the others will stay cold. So you may end up with a total re...