Don Terrill’s Speed-Talk

SlowMalibu wrote: ↑Sat Jan 13, 2024 12:18 am What is an acceptable cam to rod clearance on a 383 SBC stroker ?

I have run 30 thou with no issue.
I like using a thin piece of solder and turning engine over by hand.

Having a short block, degree wheel, dial indicator set up on a engine stand is a good place to start,compare piston position to lift and duration, opening, closing etc.build some engines and dyno and track test and see how your car performs by rocking the curve up or down. My opinion is time is bett...

X 3 ,
Chris organised a couple of cams for me via google machine, very good to deal with,I hope he is still there.

Tom68 wrote: ↑Tue Jan 09, 2024 5:41 pm Pumping losses, open that exhaust valve as high as you can.

From what I have seen in these types of combinations are less exhaust lift more duration, smoother exhaust valve motion nets more power over the curve, again its application specific.

There is one other change on the exhaust side nobody has picked up yet, Hint - it's at 92%.???? I was going to say intake to exhaust flow ratio but without reading thrifty the thread again I don't see flow numbers for these heads. What was the difference in peaks between engine dynoed in first post...

1.5 on the exhaust... That raises a question I've had since the first I read about someone using less ratio on the exhaust as opposed to the intake. What's the logic there? Is it compensating for a cam spec or working with the specifics of a particular port? Ratio speeds up valve,depending on appli...

20240106_041052.jpg Howards solid roller I have never used previously, on the 383 stuff I like a wider LSA but this ran fine on the dyno, My opinion is there might be 10hp between cams with similar IVC and EVO events and the engine tolerates everything else. Comp needle roller lifters, this is a sm...

As my fuel system development is generally an ongoing affair, I'd like to finalize it once and for all. Presently I have my system plumbed as illustrated below. Presently.jpg The filters are as shown in terms of microns. The pump is an old Holley Blue. The regulator a Holley 12-803BP. https://www.h...

Some discussion involving carb flow rates for various carb configurations was brought up in Steve Cowan’s 383 dyno thread, and I figured rather than clutter up his thread, I’d start a new one……. Let me start out by saying this is not at all meant to be a definitive set of results, but just a compar...

As my fuel system development is generally an ongoing affair, I'd like to finalize it once and for all. Presently I have my system plumbed as illustrated below. Presently.jpg The filters are as shown in terms of microns. The pump is an old Holley Blue. The regulator a Holley 12-803BP. https://www.h...

20240106_041052.jpg Howards solid roller I have never used previously, on the 383 stuff I like a wider LSA but this ran fine on the dyno, My opinion is there might be 10hp between cams with similar IVC and EVO events and the engine tolerates everything else. Comp needle roller lifters, this is a sm...

20220829_175619.jpg 20220820_173228.jpg 20220820_130755.jpg Nice Mahle pistons with 1.5 mm , 1.5 mm , 3 mm rings. I put a 4.00" oil expander in to make it low tension. EBay crank and rods from Scat I bought 10 years ago $300 AU 6" 8740 rods,size checked ,hone pin bores etc . Milodon 7 qua...

New 880 roller block fitted with howards steel caps on centre 3 mains.
These blocks are $ 2500 AUS now new.
Cylinder wall thickness after 30 thou over 0.150" - 0.190" max

Steve, I have an old 4781 that I had annular boosters installed along with thinned throttle shafts, choke tower removed, mild Venturi blending, adjustable air bleeds installed, and the fuel curve reworked. I had this done in 1991…….. before there was such a thing as an HP Holley carb. I had it done...