Don Terrill’s Speed-Talk

Thanks for all your comments, suggestions. I think my plans are solidifying. In the picture below I show 4 sets of cam plots for anyone interested or just suffering from sleeplessness, boredom: 1. Light brown or orange lines: The Alq 40/80 cams as found before recent rebuild. These were never degree...

Thanks for the comments, info. The Cosworth likely had 315+ degrees seat to seat cam duration. Thus 102 centers to keep IVC from going much over 80 ABDC. I'm struggling with whether overlap in itself makes power or whether it is just a consequence of long duration cams and the desire to keep IVC bel...

I think your assessment of the physics involved is correct. Do you have a problem with soft pedal? Fluid boiling?

I still do not understand the valve area. Is this the area of the valve head, or the area at max lift between the seat and the valve OD? This would be lift times circumference. Intakes are 43mm. EX is 37.5mm. 44mm Weber IDFs. Intake runners are about 9-10" from bottom of carb to back of valve i...

Mummert, thanks. These plots are actual valve travel at spec valve clearance. 0.014 on the milder cam and 0.010 on the CAT301. Could you help me understand the cu-In per cam degree theory vs IVC? Valve area? Is this lift x circumference? So you think 110 C/L might work better than the suggested 106?...

Put the ring in the bore, letting ends overlap. Square with an old piston. Use a dial caliper or eyeball to assess the amount of overlap. I bought oversize rings from TotalSeal as well. I think I spoke w Kevin. I think mine were nominally for 0.010 oversize bore as well, in a smaller, 84mm bore. Ste...

I am about to install new, bigger cams in my Fiat twin cam 1800cc engine project. Looking for more top end HP. Shift point 7500, try not to exceed 7800. I am looking for some advice on lobe C/L decision. My current cam is know as the Alquati 40-80/80-40 (green plot). Recommended C/L 110 for both IN/...

What do you use the keep carpeting from moving? I saw a product, sticky string adhesive that does not fully harden. Cannot locate it any more.

I do not want to use spray adhesive.

How much do the ring ends overlap in the bore?

The 3D modeling with the laser on a robot arm was pretty awesome. I assume that is in practical use even if the inconel printing may not yet be feasible?

The seat angle in the last valve picture does not look right. is it 45? Looks like 60+ in the picture.

Do the calculators use total compressed volume (head, gasket, piston, deck ht) or just the volume of the chamber in the head? Big difference.

C1500SBC, what does your 64cc number include?

To me this looks pretty amazing. Anyone here done it?

3D printed inconel exhaust header.

https://www.youtube.com/watch?v=4jbn0ah3u9E

Is there a design that circulates cooling water regardless of temp? constant flow is important to prevent localized hot spots.

If you are worried about detonation, pinging, then lower SCR to the high 9's or no more than 10.2 or so. SCR is not that significant in max HP unless you are maxing everything else. What is it that you want? Lowering SCR makes for less stress and has little effect on power in most builds I see here....