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Search found 3047 matches

by Stan Weiss
Fri Dec 03, 2021 7:09 pm
Forum: Engine Tech
Topic: Who regrinds the lifter face crown on used lifters
Replies: 12
Views: 690

Re: Who regrinds the lifter face crown on used lifters

Ron, "35 deg. face" ? Could that be 35" radius+/- instead ? While on subject, smaller the lifter diameter, less lift per degree of lobe. If this is so, why only that radius is acceptable ? Reportedly , the problem is edge of lifter will gouge the lobe ? Why not use a slightly smaller radius to prev...
by Stan Weiss
Mon Nov 29, 2021 6:05 pm
Forum: Engine Tech
Topic: Camshaft Overlap@.050" vs Idle Quality
Replies: 30
Views: 2190

Re: Camshaft Overlap@.050" vs Idle Quality

My experience has been that cams with faster ramps, and the resulting additional area within the overlap triangle, idle “rougher”. This is why Blair looks at overlap area in 4 different segments intake area ivo to evc, intake area ivo to tdc, exhaust area ivo to evc, and exhaust tdc to evc As in Pr...
by Stan Weiss
Sun Nov 28, 2021 12:49 am
Forum: Engine Tech
Topic: pontiac 461
Replies: 27
Views: 1034

Re: pontiac 461

The only way to relate valve speed to rocker arm ratio is when talking the same lobe. I believe Butler has a hyd roller that gives the same valve lift curve using 1.5:1 as the Pontiac HFT 041 does with 1.65:1 Stan Um, if you haven't seen behind the curtain, JBP doesn't know a cam from an axle. Now ...
by Stan Weiss
Sat Nov 27, 2021 3:02 pm
Forum: Engine Tech
Topic: pontiac 461
Replies: 27
Views: 1034

Re: pontiac 461

The only way to relate valve speed to rocker arm ratio is when talking the same lobe. I believe Butler has a hyd roller that gives the same valve lift curve using 1.5:1 as the Pontiac HFT 041 does with 1.65:1

Stan
by Stan Weiss
Sat Nov 27, 2021 12:25 pm
Forum: Engine Tech
Topic: Camshaft Overlap@.050" vs Idle Quality
Replies: 30
Views: 2190

Re: Camshaft Overlap@.050" vs Idle Quality

tjs44 wrote: Sat Nov 27, 2021 10:47 am Thats why your the "king"!
Tom,
"King" of what????? :wink:

Stan
by Stan Weiss
Sat Nov 27, 2021 12:24 pm
Forum: Engine Tech
Topic: Camshaft Overlap@.050" vs Idle Quality
Replies: 30
Views: 2190

Re: Camshaft Overlap@.050" vs Idle Quality

My experience has been that cams with faster ramps, and the resulting additional area within the overlap triangle, idle “rougher”. This is why Blair looks at overlap area in 4 different segments intake area ivo to evc, intake area ivo to tdc, exhaust area ivo to evc, and exhaust tdc to evc Stan ___...
by Stan Weiss
Thu Nov 25, 2021 9:29 am
Forum: Engine Tech
Topic: 2.56 Gear, Stock Converter, 4100 Pounds, NA 11s?
Replies: 125
Views: 3307

Re: 2.56 Gear, Stock Converter, 4100 Pounds, NA 11s?

I did a couple of quick calculations, using peak torque rpm (4300) and 27.4" tire (225/70/15) and w/o tire growth it comes out to 136.92 mph but, with 7.2% tire growth, it gives me the 146.76 mph. It seems reasonable that it wouldn't over come drag, after peak torque. If it could rev to 6k w/o addi...
by Stan Weiss
Wed Nov 24, 2021 9:53 am
Forum: Engine Tech
Topic: 2.56 Gear, Stock Converter, 4100 Pounds, NA 11s?
Replies: 125
Views: 3307

Re: 2.56 Gear, Stock Converter, 4100 Pounds, NA 11s?

The MPH is pretty much controlled by HP. The 60 foot / first part of the run pretty much controls the et.

Stan
by Stan Weiss
Wed Nov 24, 2021 1:12 am
Forum: Engine Tech
Topic: Nitro Top Fuel Dragster Peak HP simulations
Replies: 12
Views: 748

Re: Nitro Top Fuel Dragster Peak HP simulations

Found it, RET Nov 15 issue. Was flicking through the back issues, and found RET Jul 13 issue had the full story of the DSR engine that was the basis of the later testing. Stan, the header angle went from what degrees, to what degrees now? Will we ever see another fuel engine configuration like the ...
by Stan Weiss
Tue Nov 23, 2021 10:54 pm
Forum: Engine Tech
Topic: 2.56 Gear, Stock Converter, 4100 Pounds, NA 11s?
Replies: 125
Views: 3307

Re: 2.56 Gear, Stock Converter, 4100 Pounds, NA 11s?

More of a rough guess than a simulation

60 Foot ET = 2.1851
330 Foot ET = 5.5279
1/8 Mile ET = 8.0168
1/8 Mile MPH = 101.9771
1000 Foot ET = 10.0910
1/4 Mile ET = 11.8457
1/4 Mile MPH = 129.4106

Stan
by Stan Weiss
Tue Nov 23, 2021 8:46 pm
Forum: Engine Tech
Topic: Nitro Top Fuel Dragster Peak HP simulations
Replies: 12
Views: 748

Re: Nitro Top Fuel Dragster Peak HP simulations

Larry,
How do you account for the fact that a few years ago they changed the headers angle an picked up speed? It fact NHRA then set a limit on what the header angle has to be.

Stan
by Stan Weiss
Tue Nov 23, 2021 2:06 pm
Forum: Engine Tech
Topic: 2.56 Gear, Stock Converter, 4100 Pounds, NA 11s?
Replies: 125
Views: 3307

Re: 2.56 Gear, Stock Converter, 4100 Pounds, NA 11s?

I get this from my simulation. 60 Foot ET = 1.8935 330 Foot ET = 5.0774 1/8 Mile ET = 7.6995 1/8 Mile MPH = 93.9837 1000 Foot ET = 9.9455 1/4 Mile ET = 11.8308 1/4 Mile MPH = 120.3292 1/2 Mile ET = 18.651 -- 1/2 Mile MPH = 142.23 1 KM ET = 21.642 -- 1 KM MPH = 149.74 1 Mile ET = 30.263 -- 1 Mile MPH...
by Stan Weiss
Wed Nov 17, 2021 12:48 pm
Forum: Engine Tech
Topic: Lowering exh rocker ratio.
Replies: 35
Views: 1328

Re: Lowering exh rocker ratio.

The 18* Chevy head liked shorter exhaust duration in a comp eliminator engine I ran. Maropoluos said the head was too good on the exhaust side and was over scavenging , so the shorter duration compensated. The problem with the GM 18deg head, wasn't that the exhaust was too good. The issue was the c...
by Stan Weiss
Tue Nov 16, 2021 8:25 pm
Forum: Engine Tech
Topic: Camshaft lobe designers
Replies: 47
Views: 2214

Re: Camshaft lobe designers

Bob,
I don't know if they are called something else or not. But the Lunati lobes I was talking about above are the VooDoo series that Harold did.

Stan
by Stan Weiss
Tue Nov 16, 2021 8:03 pm
Forum: Engine Tech
Topic: Camshaft lobe designers
Replies: 47
Views: 2214

Re: Camshaft lobe designers

I wonder what program this is? April 25, 2009 by UDharold - "I am still using the commercially-available program, and all my cams since 1995 have been designed on it. I paid $10,000 for it." I believe before Harold passed he taught Jeff from Koerner Racing Engines how to use his software to design ...