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Mod | | | Forums66 Topics128,074 Posts1,055,911 Members48,429 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: May 2005 Posts: 487 'Bolter | | 'Bolter Joined: May 2005 Posts: 487 | I took my 55.1 3100 to the chassis dyno this last weekend. I don't know the history of the motor, but it's a 235 with stock single exhaust and a Rochester B. I'm using E10 fuel and have a #60 jet per Carbking's recommendation. It measured 81 HP at ~3500 RPM and 165 ft-lb at ~2200 RPM. The A/F ratio was 13 at WOT.
What do you guys think?
I was surprised as that's 25% more power than McGurk got for his stock motor in his 1955 Hot Rod Magazine build-up.
regards, Leon | | | | | Joined: Jun 2005 Posts: 388 Shop Shark | | Shop Shark Joined: Jun 2005 Posts: 388 | Which McGurk article is being cited? In the May 1955 article on the 261 McGurk measured 114 HP at 3500 RPM and 201 ft-lbf at 2000 RPM. That was on an engine dyno. In the June 1953 article on a 216 Frank measured 64 and 63 HP, respectively, at 3000 and 3500 RPM. The peak torque was 137 ft-lbf at 2000 RPM. These test were on a chassis dyno. A 1955 235 has higher compression ratio, 9% more displacement, larger intake ports, and (I think) a better cam than a 216. 20 to 26 % more torque and HP relative to a 216 seems reasonable. Hoyt | | | | | Joined: Sep 2001 Posts: 581 Shop Shark | | Shop Shark Joined: Sep 2001 Posts: 581 | Sooo . . . yer' just takin' yer engine down to the local service station for testing? Where is this dyno you're using?!  I have no idea where I would even LOOK for a "chassis dyno" around St. Louis, though I'd be interested in knowing . . . -Michael | | | | | Joined: Jun 2005 Posts: 388 Shop Shark | | Shop Shark Joined: Jun 2005 Posts: 388 | Dyno service possibility? Let us know what they say or do if you contact them. I would be interested in some testing this summer, assuming i get my street rod running. I've also heard of some other places. I'll contact some of my racing buddies and let you know. Hoyt
Last edited by hoyt; 04/08/2009 11:54 AM. Reason: writer can't spell too well
| | | | | Joined: Oct 2006 Posts: 9,671 'Bolter | | 'Bolter Joined: Oct 2006 Posts: 9,671 | All that's well and good, but Hoyt, I want to know where in the world do you dug up articles like that from 56 year old magazines??? You must have a fantasic library not to mention your memory. I remember quite well reading those HRM back in study hall, along with Honk Car Craft and Rod & Custom but even if I had kept them till today I never could have found them in the pile. I often wish those old magazines were archived and cataloged somewhere so we could all refer back to them. Maybe one day someone who has all the time in the world will do that and get them posted up on Keith Hardy's TOCMP. I can imagine how much work indexing them would be. Denny Graham Sandwihc, IL
Denny G Sandwich, IL
| | | | | Joined: Feb 2000 Posts: 5,208 'Bolter | | 'Bolter Joined: Feb 2000 Posts: 5,208 | Leon, do you have numbers below 3500 rpm? | | | | | Joined: May 2005 Posts: 487 'Bolter | | 'Bolter Joined: May 2005 Posts: 487 | I used the dyno at Speedtek in Haltom City, Texas http://www.speedtek.net/.Joe, I have the data from 2000-4000 RPM, but not with me. I can post it next week. Hoyt, the article I referenced is in this threadI though it was about a 235, but on closer inspection, it is a 216. It makes perfect sense now. regards, Leon | | | | | Joined: Jun 2005 Posts: 388 Shop Shark | | Shop Shark Joined: Jun 2005 Posts: 388 | Denny, Leon, I posted those pages about the 216 dyno tests from the 1953 HRM; in looking back, I should have have described them with a little more detail. I would like to see the rest of your dyno numbers, as we could then have a "family" of 216, 235, and 261 engine tests - spread out over 56 years and on different dynomometers - but stil useful data. When I was in school in the early sixties we did some engine dyno testing with a SBC 265 as part of a lab in IC engines. That is the extent of my hands-on dyno testing of IC engines. As part of my job, we do lots of dyno and thrust stand testing of gas turbine engines; similar but not quite the same. I started buying the Hod Rod, Honk, Car Craft, Rod and Custom, Road and Track magazines in June of 1953. I bought the back issues of HRM that were then available. which went back to January 1951. In recent years, now that the kids are all away at college or better, I have gone back to playing with interesting cars and have acquired all of the Hot Rods back to January 1948. The first three issues are reprints. Right now. I'm trying to get my street rod running so that i can start on my true love - an AD 3600, so that i can safely tow a trailer with a '32 highboy on it. Has anyone ever towed such a load with a 3100? Fifty-five years ago I was towing bigger loads with a '51 Chevy business coupe. Ignorance is bliss. Hoyt The H&W Equipment Company | | | | | Joined: May 2005 Posts: 487 'Bolter | | 'Bolter Joined: May 2005 Posts: 487 | I ran this dyno test to serve as a baseline and to determine a good timing setting. That turned out to be 10 degrees ahead of the ball in the flywheel. I'm going to put a Fenton intake with a set of Carter/Webers from Tom Langdon along with Fenton headers and Smithy's on the truck. I'll re-run the dyno tests after that and see what it bought me.
regards, Leon | | | | | Joined: May 2005 Posts: 487 'Bolter | | 'Bolter Joined: May 2005 Posts: 487 | Joe, Here's my complete results from the dyno.
regards, Leon
HP RPM--5°--10°--15° Advance 2000--59--63--63 2500--73--74--74 3000--78--81--80 3500--73--79--77 4000--n/a--66
Torque RPM----5°-10°--15° Advance 2000-155-165--165 2500-153-155-155 3000-137-142-140 3500-110-119-116 4000-n/a-87
| | | | | Joined: Feb 2000 Posts: 5,208 'Bolter | | 'Bolter Joined: Feb 2000 Posts: 5,208 | Thats very interesting, hope you get to go back once you modify the engine. Joe | | |
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