How much cam is too much?

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GARY C
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Re: How much cam is too much?

Post by GARY C »

Headguy wrote: Mon Jun 25, 2018 6:56 pm
Frankshaft wrote: Mon Jun 25, 2018 6:38 pm
Charliesauto wrote: Mon Jun 25, 2018 6:22 pm

Headguy may be looking at the same thing I noticed, the very impressive BSFC numbers.

If the numbers are correct, they have achieved tremendous efficiency for an engine with the parameters given.

Another possibility is the HP numbers are inflated to make the customer happy, which would account for the unrealistic BSFC numbers.
Oh come on Charlie, there is no happy dynos out there. It's a myth. I bet that will get 25 miles to the gallon. That's the first thing I look at, the bsfc's, But the customer is happy, that's all that matters.
The customer is only happy until he brings his car to the track and is 20mph and 2.5 seconds slower than the dyno suggests.
Could be, I have noticed the trend here where everyone else dyno #'s are wrong.
Just curious how one would inflate the #'s to create this situation and what would it make if the #'s were correct?

Just wondering because this 520 horse 357 was low to mid 4's straight motor but with a lean jetted 150 shot it dropped, I think being lean hurt the tq numbers.
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Re: How much cam is too much?

Post by CGT »

GARY C wrote: Mon Jun 25, 2018 7:15 pm
Headguy wrote: Mon Jun 25, 2018 6:56 pm
Frankshaft wrote: Mon Jun 25, 2018 6:38 pm

Oh come on Charlie, there is no happy dynos out there. It's a myth. I bet that will get 25 miles to the gallon. That's the first thing I look at, the bsfc's, But the customer is happy, that's all that matters.
The customer is only happy until he brings his car to the track and is 20mph and 2.5 seconds slower than the dyno suggests.
Could be, I have noticed the trend here where everyone else dyno #'s are wrong.
Just curious how one would inflate the #'s to create this situation and what would it make if the #'s were correct?

Just wondering because this 520 horse 357 was low to mid 4's straight motor but with a lean jetted 150 shot it dropped, I think being lean hurt the tq numbers.
Fuel flow for the nitrous not being measured by the fuel flow meter. ?
user-30257

Re: How much cam is too much?

Post by user-30257 »

CGT wrote: Mon Jun 25, 2018 7:21 pm
GARY C wrote: Mon Jun 25, 2018 7:15 pm
Headguy wrote: Mon Jun 25, 2018 6:56 pm

The customer is only happy until he brings his car to the track and is 20mph and 2.5 seconds slower than the dyno suggests.
Could be, I have noticed the trend here where everyone else dyno #'s are wrong.
Just curious how one would inflate the #'s to create this situation and what would it make if the #'s were correct?

Just wondering because this 520 horse 357 was low to mid 4's straight motor but with a lean jetted 150 shot it dropped, I think being lean hurt the tq numbers.
Fuel flow for the nitrous not being measured by the fuel flow meter. ?
Adding correction factor to an oxidized or boosted engine.
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Re: How much cam is too much?

Post by Frankshaft »

CGT wrote: Mon Jun 25, 2018 7:21 pm
GARY C wrote: Mon Jun 25, 2018 7:15 pm
Headguy wrote: Mon Jun 25, 2018 6:56 pm

The customer is only happy until he brings his car to the track and is 20mph and 2.5 seconds slower than the dyno suggests.
Could be, I have noticed the trend here where everyone else dyno #'s are wrong.
Just curious how one would inflate the #'s to create this situation and what would it make if the #'s were correct?

Just wondering because this 520 horse 357 was low to mid 4's straight motor but with a lean jetted 150 shot it dropped, I think being lean hurt the tq numbers.
Fuel flow for the nitrous not being measured by the fuel flow meter. ?
This^^^
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Re: How much cam is too much?

Post by GARY C »

CGT wrote: Mon Jun 25, 2018 7:21 pm
GARY C wrote: Mon Jun 25, 2018 7:15 pm
Headguy wrote: Mon Jun 25, 2018 6:56 pm

The customer is only happy until he brings his car to the track and is 20mph and 2.5 seconds slower than the dyno suggests.
Could be, I have noticed the trend here where everyone else dyno #'s are wrong.
Just curious how one would inflate the #'s to create this situation and what would it make if the #'s were correct?

Just wondering because this 520 horse 357 was low to mid 4's straight motor but with a lean jetted 150 shot it dropped, I think being lean hurt the tq numbers.
Fuel flow for the nitrous not being measured by the fuel flow meter. ?
Could be, I will ask the dyno operator, If I remember right it was one pump and line t'ed off but maybe only one side was metered.
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THE ABOVE POST IN NO WAY REFLECTS THE VIEWS OF SPEED TALK OR IT'S MEMBERS AND SHOULD BE VIEWED AS ENTERTAINMENT ONLY...Thanks, The Management!
user-30257

Re: How much cam is too much?

Post by user-30257 »

GARY C wrote: Mon Jun 25, 2018 7:36 pm
CGT wrote: Mon Jun 25, 2018 7:21 pm
GARY C wrote: Mon Jun 25, 2018 7:15 pm
Could be, I have noticed the trend here where everyone else dyno #'s are wrong.
Just curious how one would inflate the #'s to create this situation and what would it make if the #'s were correct?

Just wondering because this 520 horse 357 was low to mid 4's straight motor but with a lean jetted 150 shot it dropped, I think being lean hurt the tq numbers.
Fuel flow for the nitrous not being measured by the fuel flow meter. ?
Could be, I will ask the dyno operator, If I remember right it was one pump and line t'ed off but maybe only one side was metered.
Let's say it takes .42lbs/hr to make 1hp. And you make 1hp. Let's say you correct it to 2 hp. You still only burned the same fuel for one hp . How many lbs/hr did you use?

I don't agree with people adding a correction factor to a baro pressure when they are effectively adjusting their own baro pressure with boost or nitrous
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Re: How much cam is too much?

Post by GARY C »

Headguy wrote: Mon Jun 25, 2018 8:09 pm
GARY C wrote: Mon Jun 25, 2018 7:36 pm
CGT wrote: Mon Jun 25, 2018 7:21 pm

Fuel flow for the nitrous not being measured by the fuel flow meter. ?
Could be, I will ask the dyno operator, If I remember right it was one pump and line t'ed off but maybe only one side was metered.
Let's say it takes .42lbs/hr to make 1hp. And you make 1hp. Let's say you correct it to 2 hp. You still only burned the same fuel for one hp . How many lbs/hr did you use?

I don't agree with people adding a correction factor to a baro pressure when they are effectively adjusting their own baro pressure with boost or nitrous
I think that is on the dyno sheet but I don't know if both lines were being measured.
If you change the baro from NA how would you compare the gain from the power adder?
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Re: How much cam is too much?

Post by Stan Weiss »

Headguy wrote: Mon Jun 25, 2018 8:09 pm
GARY C wrote: Mon Jun 25, 2018 7:36 pm
CGT wrote: Mon Jun 25, 2018 7:21 pm

Fuel flow for the nitrous not being measured by the fuel flow meter. ?
Could be, I will ask the dyno operator, If I remember right it was one pump and line t'ed off but maybe only one side was metered.
Let's say it takes .42lbs/hr to make 1hp. And you make 1hp. Let's say you correct it to 2 hp. You still only burned the same fuel for one hp . How many lbs/hr did you use?

I don't agree with people adding a correction factor to a baro pressure when they are effectively adjusting their own baro pressure with boost or nitrous
A DCF of 2.0?
Stan

Code: Select all

Engine Size =  1.0 ci

                                 Fuel           UnCorr  UnCorr UnCorr Correct
  RPM   Horse  Torque   BMEP    lb/hr     BSFC      HP  Torque   BMEP  Factor
 5252     2.0     2.0  301.6     0.42    .4200     1.0     1.0  150.8  2.0000
AVG:
 5252     2.0     2.0  301.6     0.42    .4200     1.0     1.0  150.8
MIN:
 5252     2.0     2.0  301.6     0.42    .4200     1.0     1.0  150.8
MAX:
 5252     2.0     2.0  301.6     0.42    .4200     1.0     1.0  150.8

Average based on = 1 points

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Re: How much cam is too much?

Post by Stan Weiss »

From Gary C dyno Sheet. Only use the first few not going to type it all in.

Stan

Code: Select all

Engine Size =  358.0428 ci

                                 Fuel           UnCorr  UnCorr UnCorr Correct
  RPM   Horse  Torque   BMEP    lb/hr     BSFC      HP  Torque   BMEP  Factor
 5400   591.6   575.4  242.3   198.40    .3600   551.1   536.0  225.8  1.0735
 5500   605.4   578.1  243.5   197.10    .3400   579.7   553.6  233.2  1.0443
 5600   618.5   580.1  244.3   206.70    .3500   590.6   553.9  233.3  1.0474
 5700   626.5   577.3  243.1   205.20    .3500   586.3   540.2  227.5  1.0687
 5800   636.0   575.9  242.6   194.90    .3300   590.6   534.8  225.2  1.0768
 5900   633.0   563.5  237.3   195.50    .3300   592.4   527.4  222.1  1.0685
 6000   643.1   562.9  237.1   201.80    .3300   611.5   535.3  225.4  1.0516
AVG:
 5700   622.0   573.3  241.5   199.94    .3414   586.0   540.2  227.5
MIN:
 5400   591.6   562.9  237.1   194.90    .3300   551.1   527.4  222.1
MAX:
 6000   643.1   580.1  244.3   206.70    .3600   611.5   553.9  233.3

Average based on = 7 points
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Re: How much cam is too much?

Post by MadBill »

B.S.F.C. is calculated from uncorrected power.
Felix, qui potuit rerum cognscere causas.

Happy is he who can discover the cause of things.
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Re: How much cam is too much?

Post by Stan Weiss »

Sorry got pulled to do something else.

Number with 150 HP removed.

Stan

Code: Select all

Engine Size =  358.0428 ci

                                 Fuel           UnCorr  UnCorr UnCorr Correct
  RPM   Horse  Torque   BMEP    lb/hr     BSFC      HP  Torque   BMEP  Factor
 5400   441.6   429.5  180.9   198.40    .4493   441.6   429.5  180.9  1.0001
 5500   455.4   434.9  183.2   197.10    .4335   454.7   434.2  182.9  1.0016
 5600   468.5   439.4  185.1   206.70    .4412   468.5   439.4  185.1  1.0000
 5700   476.5   439.0  184.9   205.20    .4306   476.5   439.1  184.9   .9999
 5800   486.0   440.1  185.4   194.90    .4010   486.0   440.1  185.4   .9999
 5900   483.0   430.0  181.1   195.50    .4048   483.0   429.9  181.1  1.0001
 6000   493.1   431.6  181.8   201.80    .4092   493.2   431.7  181.8   .9999
AVG:
 5700   472.0   434.9  183.2   199.94    .4242   471.9   434.8  183.1
MIN:
 5400   441.6   429.5  180.9   194.90    .4010   441.6   429.5  180.9
MAX:
 6000   493.1   440.1  185.4   206.70    .4493   493.2   440.1  185.4

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Re: How much cam is too much?

Post by GARY C »

Stan Weiss wrote: Mon Jun 25, 2018 11:11 pm Sorry got pulled to do something else.

Number with 150 HP removed.

Stan

Code: Select all

Engine Size =  358.0428 ci

                                 Fuel           UnCorr  UnCorr UnCorr Correct
  RPM   Horse  Torque   BMEP    lb/hr     BSFC      HP  Torque   BMEP  Factor
 5400   441.6   429.5  180.9   198.40    .4493   441.6   429.5  180.9  1.0001
 5500   455.4   434.9  183.2   197.10    .4335   454.7   434.2  182.9  1.0016
 5600   468.5   439.4  185.1   206.70    .4412   468.5   439.4  185.1  1.0000
 5700   476.5   439.0  184.9   205.20    .4306   476.5   439.1  184.9   .9999
 5800   486.0   440.1  185.4   194.90    .4010   486.0   440.1  185.4   .9999
 5900   483.0   430.0  181.1   195.50    .4048   483.0   429.9  181.1  1.0001
 6000   493.1   431.6  181.8   201.80    .4092   493.2   431.7  181.8   .9999
AVG:
 5700   472.0   434.9  183.2   199.94    .4242   471.9   434.8  183.1
MIN:
 5400   441.6   429.5  180.9   194.90    .4010   441.6   429.5  180.9
MAX:
 6000   493.1   440.1  185.4   206.70    .4493   493.2   440.1  185.4

Here is the NA sheet.
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Post by dwilliams »

mag2555 wrote: Wed Jun 20, 2018 6:16 ama slightly under Camed street / strip car is fun to drive 95% of the time where as a slightly over Camed car is not fun to drive 75% of the time!
That's a sad truth too many people learn the hard way.
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Re:

Post by RevTheory »

dwilliams wrote: Tue Jun 26, 2018 8:46 am
mag2555 wrote: Wed Jun 20, 2018 6:16 ama slightly under Camed street / strip car is fun to drive 95% of the time where as a slightly over Camed car is not fun to drive 75% of the time!
That's a sad truth too many people learn the hard way.
Yep! Been there, done that.
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Re: How much cam is too much?

Post by andyf »

Another rule along the same lines is that "the older you get the smaller the cam".
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