Club Cobra
Page 3 of 3 12 3
Show 20 post(s) from this thread on one page

Club Cobra (http://www.clubcobra.com/forums/)
-   FE TALK (http://www.clubcobra.com/forums/fe-talk/)
-   -   FE Torque Curve (http://www.clubcobra.com/forums/fe-talk/119965-fe-torque-curve.html)

GT350Mike 04-03-2013 09:38 PM
Quote:
Originally Posted by blykins (Post 1238383)
Just so everyone knows....I was just ribbing on Barry. In no way was I accusing him of padding his numbers. He and I have had offline email conversations about dyno results, based on the numbers shown from other builders.

Barry is one of the builders that I can joke around with and give a hard time....some of the others are ego-centric.
For a moment, I thought this was going to get really interesting. Glad to see a little friendly rivalry.

BTW Brent, thanks for the clutch/slave cylinder info!

blykins 04-04-2013 02:59 AM
Mike, it's good to do a little poking every now and again, but at the end of the day, we're all trying to feed our families. I have a good bit of respect for Barry, and I would hope that he would reciprocate that.

Dwight, Undy had it.....hot oil with cold water makes a noticeable difference in horsepower.

blykins 04-04-2013 05:01 AM
Quote:
Originally Posted by blykins (Post 1238436)
I wish that statement could be made for all applications...but it can't.
Had a flat on the way home yesterday, so that put me behind the rest of the evening...didn't really have time to expound.

But here's my thoughts on this:

You don't cruise at 3000-3500. You cruise at 1800-2500. Dynos generally won't pull down that far, so if you're wanting a good realistic view of what's going on as you're going 60-70 mph down the highway, I don't think it would be easy or prudent to go there.

If I were an independent dyno operator, I would decline at someone's request to pull it down that far, even if I were able to. As I mentioned earlier, you don't always know what the compression ratio is, what the cam is, what the timing is, etc. You get an engine pushing 11:1 with a short cam, too much total timing, and a quick curve, and I think it would be rattle city if you tried to lug it at wide open throttle at low rpms.

A pull from 3500 will tell you everything you need to know, unless you're building an engine for your RV or dump truck. :)

DanEC 04-04-2013 06:08 AM
Quote:
Originally Posted by blykins (Post 1238484)
A pull from 3500 will tell you everything you need to know, unless you're building an engine for your RV or dump truck. :)
I wish I had had the presence of mind to request a recorded pull from 3500 on my motor. I still think it's likely the chart recorder left a little peak torque back of 4200 rpm. With 9:1 compression and a fairly mild build I don't think it would have stressed it.

blykins 04-04-2013 06:11 AM
Well, keep in mind that it's just a number. A dyno sheet is a necessary evil....

Again, not saying anything about any other builder, but you could probably bring your engine to me or Barry and the numbers would be slightly different.

GRUF78 04-04-2013 07:06 AM
Gents,

For reference, the data for the dyno runs on my motor were logged starting at 3000 RPM. Motor is a 482 FE, pump gas, 38 degrees timing in by 3500, custom Hyd roller cam, Aluminum "F" heads, 10.75 to 1 compression, 780 Holley BV Carb, Vintage Sidewinder intake, Stock distributor.

At 3000 RPM, the motor made 569 Ft-lbs of Torque and 324 HP.

At 4100 RPM, it made 601 Ft-lbs and 468 HP

At 6000 RPM, it made 520 ft-lbs and 594 HP

Pretty strong in my Cobra.

GRUFF

blykins 04-04-2013 07:18 AM
That would be pretty strong in a school bus. :)

GRUF78 04-04-2013 08:47 AM
Amen....

AL427SBF 04-04-2013 05:10 PM
Quote:
Originally Posted by blykins (Post 1238484)
Had a flat on the way home yesterday, so that put me behind the rest of the evening...didn't really have time to expound.

But here's my thoughts on this:

You don't cruise at 3000-3500. You cruise at 1800-2500. Dynos generally won't pull down that far, so if you're wanting a good realistic view of what's going on as you're going 60-70 mph down the highway, I don't think it would be easy or prudent to go there.

If I were an independent dyno operator, I would decline at someone's request to pull it down that far, even if I were able to. As I mentioned earlier, you don't always know what the compression ratio is, what the cam is, what the timing is, etc. You get an engine pushing 11:1 with a short cam, too much total timing, and a quick curve, and I think it would be rattle city if you tried to lug it at wide open throttle at low rpms.

A pull from 3500 will tell you everything you need to know, unless you're building an engine for your RV or dump truck. :)
I guess we'll agree to disagree. Not all engine dyno's are created equal, nor are the latest chassis dyno's. Fortunately for me I'll have access to a Dynapack 4000 that bolts right up to the hubs and can provide a full load via calibrated EMF at any RPM you want. These guys are local and will be doing mine when the times comes, the vette vid shows just how clean a setup it actually is.
Dyno Services | Goodies Speed Shop - San Jose CA

blykins 04-20-2013 04:45 PM
It doesn't have anything at all to do with the dyno....it has everything to do with the engine.

Still not sure why WOT data is necessary for off-idle performance....

Gaz64 04-21-2013 01:13 AM
Quote:
Originally Posted by DanEC (Post 1238084)
I had Keith Craft build my 428 stroker more for torque than raw horsepower. I witnessed the dyno pulls but didn't really sit down and closely study the dyno data until later. The recorder didn't start recording until 4200 rpm and based on everything, I always assumed that was well above the torque peak - which I figured was down somewhere in the 3600 rpm area.

I finally got curious enough to email Tony at Keith Craft and ask if they had any additional data in their file that recorded the max torque and peak rpm. He advised that the recorder starts recording when the motor hits the torque peak - indicating peak torque was at the 4100/4200 area.

I'm having a problem believing this motor's torque peak is at 4200 rpm especially with max power at 5300 rpm. What would you think?

http://i125.photobucket.com/albums/p...aEngine029.jpg
Quote:
Originally Posted by ERA Chas (Post 1238106)
I question several other things.
The heading 'A/F Ratio' is listing fuel pressure which is fine but the actual A/F Ratio would be valuable.
I think the BSFC is a bit high for these days but then I see the motor struggles to make more than 50% V/E.
Dan can you post some particulars in the motor's parts list? A 'torque' build should not have a lot of overlap or duration...:confused:
I'd want another dyno run without conflicting figures like that.

A/F ratio in the sixes is certainly wrong, and VE in the fiftys?

ERA Chas 04-21-2013 06:05 AM
Quote:
Originally Posted by Gaz64 (Post 1240810)
I'd want another dyno run without conflicting figures like that.

A/F ratio in the sixes is certainly wrong, and VE in the fiftys?
I think it was mentioned that it was dyno'd with one carb only on a dual plane. dual quad intake-accounting for A/F and VE being 50% readings. I just don't know why KC would dyno that way...
I don't know if it would read that way. And the dyno sheet does not show the test configuration of the engine.

Bob In Ct 04-21-2013 10:29 AM
I know I'm really anal about this stuff but Torque is measured in LB-FT not FT-LBS (a measure of work). Stop looking at your Craftsman torque wrench (which has it incorrect) and start looking at car ads or the charts shown on this post.

Bob


All times are GMT -7. The time now is 01:49 AM.
Page 3 of 3 12 3
Show 20 post(s) from this thread on one page

Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0
The representations expressed are the representations and opinions of the clubcobra.com forum members and do not necessarily reflect the opinions and viewpoints of the site owners, moderators, Shelby American, any other replica manufacturer, Ford Motor Company. This website has been planned and developed by clubcobra.com and its forum members and should not be construed as being endorsed by Ford Motor Company, or Shelby American or any other manufacturer unless expressly noted by that entity. "Cobra" and the Cobra logo are registered trademarks for Ford Motor Co., Inc. clubcobra.com forum members agree not to post any copyrighted material unless the copyrighted material is owned by you. Although we do not and cannot review the messages posted and are not responsible for the content of any of these messages, we reserve the right to delete any message for any reason whatsoever. You remain solely responsible for the content of your messages, and you agree to indemnify and hold us harmless with respect to any claim based upon transmission of your message(s). Thank you for visiting clubcobra.com. For full policy documentation refer to the following link: