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Old 05-23-2007, 10:29 PM   #1
68 Yellow 468
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Default Shafiroff 540 ci dyno results....

Yeah, I know this is from the Camaro, but the results could potentially help someone making a purchase decision for their C3.

Car made 531.57 rwhp and 492.9 rwtq. Timing was 32 degrees total and A/F was right around 13.0.



Quick Vid...



Car feels great...

Bryan
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Old 05-23-2007, 10:40 PM   #2
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Which 540 Shafroff motor was it? the 800hp pump gas motor? Nice results. Whats the rest of the setup? Tranny/exhaust etc?
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Old 05-23-2007, 11:45 PM   #3
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32* of timing ???? why?....that could be why it made max power at 5800. There is probably a lot of power left in it. Go throw 36* at it.
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Old 05-24-2007, 01:11 AM   #4
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Why is it that guys are getting real close to that power level from n/a 350 cube LS1's that have been modified and a supposedly strong much larger big block is only putting out a little more?

Here's an LS1 with just over 500 rwhp.
http://www.ls1tech.com/forums/showthread.php?t=602605

Last edited by 745400; 05-24-2007 at 02:05 AM.
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Old 05-24-2007, 09:12 AM   #5
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Why is it that guys are getting real close to that power level from n/a 350 cube LS1's that have been modified and a supposedly strong much larger big block is only putting out a little more?

Here's an LS1 with just over 500 rwhp.
http://www.ls1tech.com/forums/showthread.php?t=602605

Dude you just made me read through 6 pages of $hit on that ls1.tech thread. I have played with LS1s since 99 and I still can not believe they are getting that much power out of a 346. That is the only shop in the country doing that.... I gotta call BS on it. I could see MAYBE 470rwhp with the best heads, huge cam, 90/90, well tuned, open headers(cut outs) etc.... 503 is just crazy but more unbelieveable is the 400 ft lbs of tq at 3500... With no stroke in it??? I don't think so...I think that shop has a good advertising campaign to sell heads and cams.

MTI which is the most renowned LS1 shop in the country only gets 500-520rwhp out of their 427", Stg 3 heads(based on AFR), 90/90setup and thats a $20k motor.... Still impressive no doubt but.... you can buy a shafroff 540 for $11k turn key.
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Old 05-24-2007, 09:16 AM   #6
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ajrothm - It is a 700 hp motor. TKO-600, Ford 9", 3" exhaust with dynomax mufflers.

69 N.O.X. RATT - I will tell you how that went down and I would be curious as to your thoughts. Before we did any dyno pull, we checked the initial timing, total timing, and timing curve just to see where Shafiroff had set it. We expected it to be conservative just because the motor does come with a warranty. Here was baseline: 11 degree of initial timing, 29 degree total timing with all of the timing in at 2,800 rpms. We then did a baseline pull to see where we were at. Next, we put in 3 degrees of initial timing to get initial timing of 14 degrees and total timing of 32 degrees and then did another dyno pull. At this point, the motor only picked up 8 HP. I had expected a bit more of an increase than that and since it was such a small increase, I decided to leave well enough alone as my number one priority yesterday was NOT to blow anything up. That being said, we left the timing as it was and started to tune from there. What would you have done at that point??

745400 - Head design for one. But, to be fair, I have a dyno I am looking at of a C6Z06 with cam, headers, airbox, tune and no cats that is putting down 556 rwhp and 482 rwtq. So, the peaks are higher than my setup. Interestingly enough, at 4,000 rpms my motor is up 45 rwhp and 70 rwtq over the Z06 motor. I will also say that my setup is a very 'mild' setup and I enjoy driving it a great deal.

B.
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Old 05-24-2007, 12:51 PM   #7
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I would have pulled a plug and took a look at it. I am sure it will make more power at 36-38* of timing. What gas are you running in it? 99% of conventional BBC's make best power at 36-38* of timimng particulaly with decent gas in it.
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Old 05-24-2007, 05:37 PM   #8
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Quote:
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I would have pulled a plug and took a look at it. I am sure it will make more power at 36-38* of timing. What gas are you running in it? 99% of conventional BBC's make best power at 36-38* of timimng particulaly with decent gas in it.
I am running Exxon 93 Octane fuel.
So, you think to start easing up on the timing, check the plugs and see where we get?
Any surprise that the inital 3 degrees of timing did not get us more HP?
Also, does the initial timing look good to you?
Thanks for your expertise and clean up your Private messages when you get a minute.

Bryan
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Old 05-24-2007, 07:14 PM   #9
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How many cubes? I think you'll do better with more timing as well. Your A/F ratio seemed a bit on the lean side to me, below what 4 grand or so. Max hp is typically in the 12.5-12.7 range. If it were me, I'd fatten it up just a bit also. Remember, one thing, and one thing only, makes hp, and that is burning fuel. Every last thing we do to make more hp is in support of burning that fuel. So don't short change yourself by running leaner than optimum. Of course I'm talking about WFO throttle here, not cruising.
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Old 05-24-2007, 07:37 PM   #10
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How many cubes? I think you'll do better with more timing as well. Your A/F ratio seemed a bit on the lean side to me, below what 4 grand or so. Max hp is typically in the 12.5-12.7 range. If it were me, I'd fatten it up just a bit also. Remember, one thing, and one thing only, makes hp, and that is burning fuel. Every last thing we do to make more hp is in support of burning that fuel. So don't short change yourself by running leaner than optimum. Of course I'm talking about WFO throttle here, not cruising.
540 cubes here as well.

I agree with you on the air fuel. We ended up jetting up to 90 for the primaries and 92 for the secondaries just to get us to 13.0. Car was stumbling a bit at cruising speed because of the large jets so we have to do a bit of work on the carb before hitting the dyno again. My goal is a 12.5 air fuel as well.
I plan to hit the dyno again late next week with the carb dialed in (dropping back down to 87/89 jets) and playing with the timing a bit more.
Any more direction you would offer up?

B.
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Old 05-24-2007, 09:28 PM   #11
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ajrothm - It is a 700 hp motor. TKO-600, Ford 9", 3" exhaust with dynomax mufflers.

69 N.O.X. RATT - I will tell you how that went down and I would be curious as to your thoughts. Before we did any dyno pull, we checked the initial timing, total timing, and timing curve just to see where Shafiroff had set it. We expected it to be conservative just because the motor does come with a warranty. Here was baseline: 11 degree of initial timing, 29 degree total timing with all of the timing in at 2,800 rpms. We then did a baseline pull to see where we were at. Next, we put in 3 degrees of initial timing to get initial timing of 14 degrees and total timing of 32 degrees and then did another dyno pull. At this point, the motor only picked up 8 HP. I had expected a bit more of an increase than that and since it was such a small increase, I decided to leave well enough alone as my number one priority yesterday was NOT to blow anything up. That being said, we left the timing as it was and started to tune from there. What would you have done at that point??

745400 - Head design for one. But, to be fair, I have a dyno I am looking at of a C6Z06 with cam, headers, airbox, tune and no cats that is putting down 556 rwhp and 482 rwtq. So, the peaks are higher than my setup. Interestingly enough, at 4,000 rpms my motor is up 45 rwhp and 70 rwtq over the Z06 motor. I will also say that my setup is a very 'mild' setup and I enjoy driving it a great deal.

B.
Did you get a dyno sheet with this from them? Seems to me that if it is making 700HP at the flywheel it should be around 595 at the rear wheels based on a typical 15% loss through the powertrain and accessories. 537HP is still alot of zip but seems like it should be more.
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Old 05-24-2007, 10:07 PM   #12
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Did you get a dyno sheet with this from them? Seems to me that if it is making 700HP at the flywheel it should be around 595 at the rear wheels based on a typical 15% loss through the powertrain and accessories. 537HP is still alot of zip but seems like it should be more.

Yes, I did get a dyno sheet. I am satisifed enough with the rwhp numbers as they are close to what my vette is making with the 468 I have in it (which is not making too much less than the 540 in the camaro).
What I find interesting is that some of Camaro's that I have seen that have motors that make more flywheel horsepower than mine have made less rwhp than mine. Strange.
Another mind bender is that the GM ZZ502 that is in a corvette members C3 put down something like 400 rwhp (502 flywheel HP) and the 505 flywheel HP C6Z06 puts down something like 450 rwhp stock. Again, strange.
I don't claim to know too much about what all of this means. What I do know is that I have had a variety of high HP cars and I can say that this Camaro runs like crazy. If it does not trap close to 130 mph in the quarter, I would be surprised.

B.
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Old 05-24-2007, 10:10 PM   #13
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Originally Posted by 69 N.O.X. RATT View Post
I would have pulled a plug and took a look at it. I am sure it will make more power at 36-38* of timing. What gas are you running in it? 99% of conventional BBC's make best power at 36-38* of timimng particulaly with decent gas in it.
I agree. Mine didn't start to come alive until I was at 34 degrees total - at 36 now and it shuts off fine and pulls good.
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Old 05-24-2007, 11:00 PM   #14
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Originally Posted by Irish69427 View Post
Did you get a dyno sheet with this from them? Seems to me that if it is making 700HP at the flywheel it should be around 595 at the rear wheels based on a typical 15% loss through the powertrain and accessories. 537HP is still alot of zip but seems like it should be more.

I think his numbers are pretty close to accurate. No way there is only a 15% drivetrain loss going though heavy driveshafts and a 9" ford.
More like 20-25%. The type of tires will also affect the dyno.

It would be worse on his vette, the IRS is a HP killer. 30% with an auto and tight converter is average.

Either way that camaro is gonna haul ***. If it hooks and doesn't break, thats a mid 10 sec car.
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Old 05-24-2007, 11:20 PM   #15
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Originally Posted by 68 Yellow 468 View Post
ajrothm - It is a 700 hp motor. TKO-600, Ford 9", 3" exhaust with dynomax mufflers.

69 N.O.X. RATT - I will tell you how that went down and I would be curious as to your thoughts. Before we did any dyno pull, we checked the initial timing, total timing, and timing curve just to see where Shafiroff had set it. We expected it to be conservative just because the motor does come with a warranty. Here was baseline: 11 degree of initial timing, 29 degree total timing with all of the timing in at 2,800 rpms. We then did a baseline pull to see where we were at. Next, we put in 3 degrees of initial timing to get initial timing of 14 degrees and total timing of 32 degrees and then did another dyno pull. At this point, the motor only picked up 8 HP. I had expected a bit more of an increase than that and since it was such a small increase, I decided to leave well enough alone as my number one priority yesterday was NOT to blow anything up. That being said, we left the timing as it was and started to tune from there. What would you have done at that point??

745400 - Head design for one. But, to be fair, I have a dyno I am looking at of a C6Z06 with cam, headers, airbox, tune and no cats that is putting down 556 rwhp and 482 rwtq. So, the peaks are higher than my setup. Interestingly enough, at 4,000 rpms my motor is up 45 rwhp and 70 rwtq over the Z06 motor. I will also say that my setup is a very 'mild' setup and I enjoy driving it a great deal.

B.
Interesting. I agree with you on the camaro vs. vette power to the rear wheels issue. I have a 1968 Firebird with a 455 and it doesn't seem to put down the power to rear wheels as efficiently as my vette does either. Despite having the same trans. I suspect part of it is the straight axle rearend. In your case the 9" ford is bullet proof but it will suck some power. Did you buy the 540/695 classic. I have been thinking about that motor as well. Were you happy with all aspects of the purchase, etc. Any problems?
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Old 05-24-2007, 11:31 PM   #16
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I think his numbers are pretty close to accurate. No way there is only a 15% drivetrain loss going though heavy driveshafts and a 9" ford.
More like 20-25%. The type of tires will also affect the dyno.

It would be worse on his vette, the IRS is a HP killer. 30% with an auto and tight converter is average.

Either way that camaro is gonna haul ***. If it hooks and doesn't break, thats a mid 10 sec car.
Wow! You really think 30% with an auto. Can't speak to that as I have never owned one. But I think that is way to high for a stick. My 489 dynoed 538HP at 6000 and 550 ft lbs at 4300. At the track it had a trap speed of 120. With me in it the car weighed 3500. On my power speed calculator that is about 470 HP at the rear wheels. If I add back in 15% I get about 540 HP at the flywheel which is very close to my engine dyno runs.
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Old 05-24-2007, 11:41 PM   #17
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Interesting. I agree with you on the camaro vs. vette power to the rear wheels issue. I have a 1968 Firebird with a 455 and it doesn't seem to put down the power to rear wheels as efficiently as my vette does either. Despite having the same trans. I suspect part of it is the straight axle rearend. In your case the 9" ford is bullet proof but it will suck some power. Did you buy the 540/695 classic. I have been thinking about that motor as well. Were you happy with all aspects of the purchase, etc. Any problems?

I did buy the classic with a few differences: 1). Classic comes with a dominator setup and I opted for the 4150 style carb for drivability. 2). I went with a hyd. roller instead of the solid 3). A bit better heads 4). A few build differences (aluminum block, bottom end components, etc).
Motor dropped right in and fired RIGHT up. It's been problem free and I am very satisfied.

Bryan
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Old 05-24-2007, 11:45 PM   #18
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Wow! You really think 30% with an auto. Can't speak to that as I have never owned one. But I think that is way to high for a stick. My 489 dynoed 538HP at 6000 and 550 ft lbs at 4300. At the track it had a trap speed of 120. With me in it the car weighed 3500. On my power speed calculator that is about 470 HP at the rear wheels. If I add back in 15% I get about 540 HP at the flywheel which is very close to my engine dyno runs.
hhmm....the old 468 ci motor in the vette made 602 HP on an engine dyno and 450 rwhp on a dynojet. That is right about 25% evem with a 6 speed tranny.

B.
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Old 05-25-2007, 12:02 AM   #19
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Now I really wish I would have chassis dynoed the car. Unfortunately, I'll never have the chance as it was in an accident and totalled. All I have to go on are the engine dyno and the dragstrip trap speed. Based on your chassis dyno results, mine seem to optimistic, but I am pretty sure I did the slide rule right. Will you be drag racing the car?Would be interesting to see what kind of rear wheel horsepower it shows at the track. In any event, its going to scream. Sounds like a really nice motor.
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Old 05-25-2007, 12:29 AM   #20
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Wow! You really think 30% with an auto. Can't speak to that as I have never owned one. But I think that is way to high for a stick. My 489 dynoed 538HP at 6000 and 550 ft lbs at 4300. At the track it had a trap speed of 120. With me in it the car weighed 3500. On my power speed calculator that is about 470 HP at the rear wheels. If I add back in 15% I get about 540 HP at the flywheel which is very close to my engine dyno runs.
Some additional loss not accounted for through drivetrain is the fan/accessories/fuel pump etc.

As for 30% DT loss, yes thats high. I should have mentioned thats through a TH400 and IRS, with a stock fan and mech fuel pump.

I would say on a stick car with straight axle and clutch fan, 20% is an accurate number.

Your car trap'n 120 is haul'n ***. I would say it would take 450rwhp to go 120mph at 3500lbs raceweight on a good setup car.

I guess i just always thought 15% was a little low, even for efficient setups. Hell I wouldn't care if I was trap'n 120mph...LOL
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Old 05-25-2007, 12:29 AM
 
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