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Search found 2774 matches

by David Redszus
Fri Sep 13, 2019 3:36 pm
Forum: Engine Tech
Topic: Torque To Yield
Replies: 30
Views: 785

Re: Torque To Yield

The once simple task of bolting two items together has become an engineering discipline. A bolt is not just a bolt, but part of a fastener system, consisting of bolt, nut (or threaded hole), washer and clamped material. Each component must be considered as to its contribution to the system. Followin...
by David Redszus
Thu Sep 12, 2019 4:53 pm
Forum: Engine Tech
Topic: Air/ fuel ratio data logger
Replies: 22
Views: 920

Re: Air/ fuel ratio data logger

Innovate Lm-2 is a good choice. AEM makes both wide band o2 sensor controllers and has data loggers that are not too expensive. They have a very good reputation for accuracy. I have the AEM wideband controller kit that does not have a gauge - 30-0310. It goes direct to the logger of your choice, it...
by David Redszus
Thu Sep 12, 2019 4:50 pm
Forum: Engine Tech
Topic: Tight lash camshaft questions
Replies: 31
Views: 1347

Re: Tight lash camshaft questions

A ramp height of .020" over 40 deg would produce a slope of 2 deg/.001". That is to say a change in lash of .001" would result in a duration change of 2 deg. Actually, it would change 4 degrees, because you would be changing each side 2 degrees. Thanks Mike, you are correct. I should have said 2 de...
by David Redszus
Thu Sep 12, 2019 12:22 pm
Forum: Engine Tech
Topic: Tight lash camshaft questions
Replies: 31
Views: 1347

Re: Tight lash camshaft questions

I guess a tight lash lobe would be a constraint for someone who wanted to experiment with changing lash as a signpost re the benefit of more/less duration? Bill, I don't see why trying the lash looser would be any different between a tight and loose lash cams. Now if you want to try a tighter lash ...
by David Redszus
Wed Sep 11, 2019 10:52 am
Forum: Engine Tech
Topic: Torque To Yield
Replies: 30
Views: 785

Re: Torque To Yield

By definition, a bolt should be torqued into its elastic range but not into its plastic range. If within its elastic range,the bolt should return to its original length. If it does not, it's use is problematic. Some OEMs will specify a used bolt critical dimension; either length or diameter, within ...
by David Redszus
Wed Sep 11, 2019 10:23 am
Forum: Engine Tech
Topic: Tight lash camshaft questions
Replies: 31
Views: 1347

Re: Tight lash camshaft questions

Bill, I don't see why trying the lash looser would be any different between a tight and loose lash cams. Now if you want to try a tighter lash setting then you would probable have to set the valves hot on the dyno. Stan A constant velocity ramp would consist of a slope (rise over run) for a certain...
by David Redszus
Wed Sep 11, 2019 1:47 am
Forum: Engine Tech
Topic: Tight lash camshaft questions
Replies: 31
Views: 1347

Re: Tight lash camshaft questions

I guess a tight lash lobe would be a constraint for someone who wanted to experiment with changing lash as a signpost re the benefit of more/less duration? Bill, I don't see why trying the lash looser would be any different between a tight and loose lash cams. Now if you want to try a tighter lash ...
by David Redszus
Tue Sep 10, 2019 1:47 pm
Forum: Engine Tech
Topic: Tight lash camshaft questions
Replies: 31
Views: 1347

Re: Tight lash camshaft questions

Mike, what lash do your cams have for the most part? We use a .012" Lash ramp on most of our roller profiles, so Hot Lash would be .012" x Rocker Ratio. We chose .012", because if you go down to a .010" ramp, with an Aluminum block and Aluminum heads, the lash growth from cold to hot, would be more...
by David Redszus
Fri Sep 06, 2019 11:58 am
Forum: Engine Tech
Topic: Air/ fuel ratio data logger
Replies: 22
Views: 920

Re: Air/ fuel ratio data logger

I would never recommend an O2 gauge in a track car; they are useless. Due to the fact that O2 values change with rpm and that they vary cycle to cycle, a gauge simply does not reveal what is actually going on. Do not look for a single value O2 number; doesn't exist in the real world. A wide range of...
by David Redszus
Thu Sep 05, 2019 11:34 am
Forum: Engine Tech
Topic: Alcohol fuel users
Replies: 5
Views: 381

Re: Alcohol fuel users

Methanol is a warm weather fuel best used on hot turbo engines.
by David Redszus
Thu Sep 05, 2019 11:32 am
Forum: Engine Tech
Topic: Air/ fuel ratio data logger
Replies: 22
Views: 920

Re: Air/ fuel ratio data logger

We sell a data logger that will measure and log rpm and one Lambda. It sells for $900, including software.
by David Redszus
Wed Sep 04, 2019 10:42 am
Forum: Engine Tech
Topic: Custom vs Catalog Cams
Replies: 204
Views: 8612

Re: Custom vs Catalog Cams

Doing non mainstream engines with a catalogue cam gets you the typical 10 or 15 more ex duration with that lobe just being the next one in line as the intake lobe..and on and on. I usually prefer much faster ramp rates on intakes than ex, so it's almost always a custom order to get a softer and sim...
by David Redszus
Tue Sep 03, 2019 12:18 pm
Forum: Engine Tech
Topic: Volumetric efficiency from hp
Replies: 20
Views: 841

Re: Volumetric efficiency from hp

I think this web site/page helps on answering many questions on VE and BMEP and others. BMEP :) John that is an excellent link to useful engine information. It should be carefully read and copied for future reference. It would help destroy many bogus claims for massive power from under developed en...
by David Redszus
Sat Aug 31, 2019 1:33 pm
Forum: Engine Tech
Topic: Tq / Hp Estimate
Replies: 4
Views: 278

Re: Tq / Hp Estimate

Basically had these parts laying around and threw this combo together on the fly to see how it would run. Anyone care to take a guess at what you think it might make. 4.030 x 3.48 6 inch rods 10.85 to 1 CR Dart pro 1 215cc heads out of the box 2.05 1.60 valves 2 valve notch flat tops Zero deck Soli...
by David Redszus
Sat Aug 31, 2019 1:23 pm
Forum: Engine Tech
Topic: Volumetric efficiency from hp
Replies: 20
Views: 841

Re: Volumetric efficiency from hp

Dyno lies. :) It´s not gonna be 220hp/ 8000 rpm 1600cc NA. 144 ft-lb from 1600cc (1.47 ft-lb/CI) is totally plausible Plausible but.... That combination would result in a BMEP of 15.4 bar. That is Formula One territory. Very unlikely for a two valve engine but possible for a very, very, well develo...