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Re: Race Engine Challenge II

Posted: Tue Nov 07, 2017 3:42 pm
by GARY C
CamKing wrote:
Tue Nov 07, 2017 3:37 pm
randy331 wrote:
Tue Nov 07, 2017 3:14 pm
Then open the rules up and make sure us hobbyists can't copy it at home.

Any V8 0f no more than 410 cubes, no more than 2 valves per cylinder, no more than 2 carbs, or throttle bodies.


No RPM limit, you get to pick your best 1500 rpm, best average over that 1500 rpm wins.
Leave TQ out of scoring.

Randy
I think you will see that class added in the future.
for now, these engines are supposed to represent top-of-the-line street/strip engines, that will last a given number of miles on the street.
We can't run them them on the dyno for 1,000 hours each, to know they'll last, so we have to have rules that lessen the advantages you would see from building a dyno queen ,that's designed to last just as long as the competition. RPM & Valve lift limits, do just that.
No but you could require that the engine is ran at say 3500 rpm until you reach am oil temp of say 210 degrees and a water temp of 160 or what ever represents full operating temps before the dyno pull is started so that the builder has to factor in some sort of reliability.

Re: Race Engine Challenge II

Posted: Tue Nov 07, 2017 3:45 pm
by CamKing
GARY C wrote:
Tue Nov 07, 2017 3:42 pm
No but you could require that the engine is ran at say 3500 rpm until you reach am oil temp of say 210 degrees and a water temp of 160 or what ever represents full operating temps before the dyno pull is started so that the builder has to factor in some sort of reliability.
That's something to think about.

Re: Race Engine Challenge II

Posted: Tue Nov 07, 2017 3:47 pm
by David Vizard
randy331 wrote:
Tue Nov 07, 2017 3:14 pm
Then open the rules up and make sure us hobbyists can't copy it at home.

Any V8 0f no more than 410 cubes, no more than 2 valves per cylinder, no more than 2 carbs, or throttle bodies.


No RPM limit, you get to pick your best 1500 rpm, best average over that 1500 rpm wins.
Leave TQ out of scoring.

Randy
Randy,
Definitely not in for this!!
DV

Re: Race Engine Challenge II

Posted: Tue Nov 07, 2017 4:02 pm
by randy331
GARY C wrote:
Tue Nov 07, 2017 3:42 pm
No but you could require that the engine is ran at say 3500 rpm until you reach am oil temp of say 210 degrees and a water temp of 160 or what ever represents full operating temps before the dyno pull is started so that the builder has to factor in some sort of reliability.
There is some reliability already factored in.
The need to do some testing on the dyno before the competition requires some reliability.

The BES Big block Mopar is going right in a street car. Flat tappet cam titanium valves and all.

Our engine could too, but I'd want a hyd roller in it first. Other wise it wouldn't require any changes at all.

The dyno is easy on an engine compared to most racing situations.

The pulling truck engine I'm building is gonna be abused more in the truck than the dyno. The dyno is nice controlled sweeps, with no surges from traction changing etc. In the truck it will sit at 8500-9000 rpm for 15 seconds or more at a time with just the cooling system in the truck. No pre set thermostat cooling tower to help. It may spin out to the rev limiter at the end of the track or the sled may gut it back down through the rpm range. May have to come around and re hook in just a few minutes too.

Randy

Re: Race Engine Challenge II

Posted: Tue Nov 07, 2017 4:56 pm
by Walter R. Malik
David Vizard wrote:
Tue Nov 07, 2017 12:42 pm
Walter R. Malik wrote:
Mon Nov 06, 2017 9:33 am
David Vizard wrote:
Mon Nov 06, 2017 9:02 am

Surely everyone would want to install the largest air-flow productive intake valve into whatever they are building. So If the largest effective valve is installed then there is no point in lifting it more than 38% of whatever the diameter of the valve is. This should mean a level playing field as far as valve lift is concerned - should it not?

DV
Not really true ... Personally, I installed a larger intake valve and gained air flow into one of my past EMC engines ... and gained a little maximum torque and horsepower only to LOSE power everywhere below the RPM of that peak torque figure.
Just have a maximum valve lift figure here at "0" lash and they can use whatever valve size they want.

That was a change during testing that I wish I never made because it would now take installing 8 seats to go back. So, I left it that way.

Walter,

I know you are a real engine pro here so I really hate to ask this as I feel it might even go to the extent of seemingly being an insult so let me apologize ahead of time.

My question is if you were sure the cam was on the right LCA and in at the right advance did you spread the LCA for the increased low lift flow potential of the bigger valve and retard the cam the appropriate amount for the bigger intake (I assume only the intake was increased)?

If not then the test results may not be as meaningful as you may be supposing.
NO .. all that would have been to expensive for me so, I simply moved around the timing of the cam in the engine with also changing some rocker arm ratios around to arrive at the best numbers while using the stuff I already had.

Re: Race Engine Challenge II

Posted: Tue Nov 07, 2017 5:20 pm
by GARY C
CamKing wrote:
Tue Nov 07, 2017 3:45 pm
GARY C wrote:
Tue Nov 07, 2017 3:42 pm
No but you could require that the engine is ran at say 3500 rpm until you reach am oil temp of say 210 degrees and a water temp of 160 or what ever represents full operating temps before the dyno pull is started so that the builder has to factor in some sort of reliability.
That's something to think about.
I just thought it might limit some from trying to make a 5 pull dyno grenade. :D

Re: Race Engine Challenge II

Posted: Tue Nov 07, 2017 5:43 pm
by David Vizard
David Vizard wrote:
Tue Nov 07, 2017 12:42 pm
Walter,

I know you are a real engine pro here so I really hate to ask this as I feel it might even go to the extent of seemingly being an insult so let me apologize ahead of time.

My question is if you were sure the cam was on the right LCA and in at the right advance did you spread the LCA for the increased low lift flow potential of the bigger valve and retard the cam the appropriate amount for the bigger intake (I assume only the intake was increased)?

If not then the test results may not be as meaningful as you may be supposing.
Walter you replied:- NO .. all that would have been to expensive for me so, I simply moved around the timing of the cam in the engine with also changing some rocker arm ratios around to arrive at the best numbers while using the stuff I already had.

I understand the lack of budget - you obviously did the best with what you had - which I kind of suspected.

DV

Re: Race Engine Challenge II

Posted: Tue Nov 07, 2017 5:51 pm
by CREngines
mandatory valve spring part number SBI 160-1144HP, to be supplied the day of the test, stainless valves min stem diameter 5/16.

Open rules other wise.

Tell me that wont put a handle on the situation. :mrgreen:

Re: Race Engine Challenge II

Posted: Tue Nov 07, 2017 6:08 pm
by CamKing
CREngines wrote:
Tue Nov 07, 2017 5:51 pm
mandatory valve spring part number SBI 160-1144HP, to be supplied the day of the test, stainless valves min stem diameter 5/16.

Open rules other wise.

Tell me that wont put a handle on the situation. :mrgreen:
That's one of the first things I thought of.
Problem is, with the multiple engine platforms, and multiple CID engines, the spec spring rule would allow the smaller CID engines with the smaller valves, to run much more aggressive cam designs.

Re: Race Engine Challenge II

Posted: Tue Nov 07, 2017 6:26 pm
by plovett
CamKing wrote:
Tue Nov 07, 2017 6:08 pm
CREngines wrote:
Tue Nov 07, 2017 5:51 pm
mandatory valve spring part number SBI 160-1144HP, to be supplied the day of the test, stainless valves min stem diameter 5/16.

Open rules other wise.

Tell me that wont put a handle on the situation. :mrgreen:
That's one of the first things I thought of.
Problem is, with the multiple engine platforms, and multiple CID engines, the spec spring rule would allow the smaller CID engines with the smaller valves, to run much more aggressive cam designs.
I think that might be a good thing. A spec spring would show the advantage of smaller CID engines with smaller lighter valve trains. We're so often doing the opposite. I'm not going to say that stupid rhyme about large volume engines.

JMO,

paulie

Re: Race Engine Challenge II

Posted: Tue Nov 07, 2017 7:28 pm
by randy331
Walter R. Malik wrote:
Mon Nov 06, 2017 9:33 am
Not really true ... Personally, I installed a larger intake valve and gained air flow into one of my past EMC engines ... and gained a little maximum torque and horsepower only to LOSE power everywhere below the RPM of that peak torque figure.
Just have a maximum valve lift figure here at "0" lash and they can use whatever valve size they want.

That was a change during testing that I wish I never made because it would now take installing 8 seats to go back. So, I left it that way.
I made a similar change, with similar results on our EMC engine.

Between the first and second dyno session I went from 2.055" valve with 50* seat to a 2.08" valve with 45* seat. No other changes.
The CFM was up considerably after the change, but that set of heads went backwards on score compared to the other set of heads.
On the first dyno session the 2 sets of heads scored almost spot on to each other with any cam or intake we tried.
It eliminated them from use on that engine.

Randy

Re: Race Engine Challenge II

Posted: Wed Nov 08, 2017 9:03 am
by Vee-Dizzie
randy331 wrote:
Tue Nov 07, 2017 7:28 pm
Between the first and second dyno session I went from 2.055" valve with 50* seat to a 2.08" valve with 45* seat. No other changes.
The CFM was up considerably after the change, but that set of heads went backwards on score compared to the other set of heads.
On the first dyno session the 2 sets of heads scored almost spot on to each other with any cam or intake we tried.
It eliminated them from use on that engine.
Not as uncommon as one would think..sounds like a good example of one of the ways a flow bench can be dishonest to its master!!!!! THANKS FOR SHARING THAT!!!!!

Re: Race Engine Challenge II

Posted: Wed Nov 08, 2017 9:35 am
by Vee-Dizzie
randy331 wrote:
Tue Nov 07, 2017 7:28 pm
Between the first and second dyno session I went from 2.055" valve with 50* seat to a 2.08" valve with 45* seat. No other changes.
The CFM was up considerably after the change, but that set of heads went backwards on score compared to the other set of heads.
On the first dyno session the 2 sets of heads scored almost spot on to each other with any cam or intake we tried.
It eliminated them from use on that engine.
Perhaps a change in Lobe Separation Angle would have told you a different story.........or an improvement in your testing methods.

Re: Race Engine Challenge II

Posted: Wed Nov 08, 2017 9:39 am
by In-Tech
or perhaps the 2.08 with a 50 degree seat :wink:

Re: Race Engine Challenge II

Posted: Wed Nov 08, 2017 9:56 am
by CGT
Vee-Dizzie wrote:
Wed Nov 08, 2017 9:35 am
Perhaps a change in Lobe Separation Angle would have told you a different story.........or an improvement in your testing methods.
:lol: