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Dyno Day today & results with comparison

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Brosky

Brosky

Great Pumpkin
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These are the charts from the four (4-5-6-7) pulls. It shows that my HP and Torque came up quite a bit from where I started and that the cam does what it said it would. The last pull was run up to 6,000rpms to check the curve and see if it would climb beyond where the 5,200 peak seemed to be. As you can see, it fell right off, so the TH5 is supposed to have mid range power up to 5,000 and it does.

We did lean out the mixture one quarter turn between runs 4 to 5-6 and decided to leave it alone at that point.

The #3 pull from 2007 is evident as well as the pig rich A/F ratio that was probably part of the two exhaust lobes that were down to 1/2 their starting size.

So here it is:

Dyno-2010-1a.jpg


Dyno-2010-2a.jpg
 
Yes. I never believed any of the hype about the 150HP stuff, so this is what I expected from what I have.

Maybe, 150 on a dyno direct, but never at rear wheels.
 
According to my quick calculations, if you started off with 77 HP with a stock engine rated at about 105 HP, then the 150 HP claim at the crank falls right into line with the drive line loses and your 113 HP reading. This is a huge increase over stock...like 45%. :thumbsup:
 
Well, that is what I meant Art. It would have to be at the crank, or as direct, as mis-stated it.

Believe it or not, there was talk ta the dyno shop about the CV joints actually dragging the HP down, over the axles based on some Miata results recently. Apparently, there are a LOT of Miata racers that use his shop for super tuning and they are concious of every little factor. John said that depending on how he straps a car down, he can drag 5-7HP out of it.

Eric from Her Majesty's was there and helped tweak mine and a few others and there was also a full race TR6 there being tuned. This was Erik's comments after many runs from the TR6:

"I don't think you did too bad. The TR6 race car only pulled 141rwhp and he's got 12.5:1 compression, a full race cam, running race gas, and about 50 hours into his cyl. head. And that was after rejetting his webers after the first pull."
 

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The CV joints will make more power over a U-Joint. I was talking to Sam Halkias a few years back, and he said he saw a couple of hp more on the dyno with the CV's, and a couple mph on the top end. The angle will effect both U and CV joints.

That TR6 is an autocrosser car. I'm not sure how it compares to the top notch road race cars, and it might be set up to produce more mid range at the expense of top end. 141whp sounds really low for a full race TR6 motor (should be 175+), but it could just be the dyno.
 
Brosky said:
Maybe, 150 on a dyno direct, but never at rear wheels.
Click to expand...
OH yas.

Very likely, not just measured at the flywheel, but with the air filter, fan, water pump, alternator, etc. disconnected. That was common back then.

ISTR changing the measurement conditions was one of the primary reasons the rating later dropped to 135 from 150.
 
Bob,

I tend to agree with you, but as I stated, just the way it's held down can create a difference. I have a guideline to follow now, should I decide to tweak it more. Erik did take a video with his small camera of the AF ratio at WOT and that is what I wanted to see. I stayed in the very low 12 range on the two final runs and that is fine with me.

Randall, when the HP rating games were being played, nothing was held back....in either direction. When I worked for Oldsmobile in 1970, we were at a Service Managers conference in East Lansing and they had three factory fresh W-30 442's that were loaded with every performance option. Double disk clutch, everything. That had them on the dynos and they were screaming well over 480HP and tons of torque. But to keep the insurance regulators and corporate happy, they were HP listed well below the 455 CI. The GM rule was no engine made more HP than the CI displacement, except for the 427 Corvette, no matter what any dyno said.
 
Heh heh ... I don't doubt it, Paul!

It's a shame there has never been an equivalent to the Nebraska tests for cars.
 
My 1970 454 Vette was listed at 390 horses and 500 ft/lbs of torque. We dynoed it at 435. Chevrolet did indeed produce a few "bad boys" 454's, pressing 500 horses. I think there were only a few.
 
Another example is the 426 Hemi with the 2X4bbl carbs. 425HP....yeah right...closer to 525 and the 440 6Pack was sneaky, but was never 390HP, more like 450HP.
 
I will do that Don, but I have to play with the needles and or jets to get there. I will do that after I get another set of slightly leaner needles and after Jeff at Advanced has a chance to look the results over. I want him to see the curve and see if he can improve on anything on that side, so I can do it all at once.

Now if I could only find that thread with the needle numbers that are the next step down. I think that either Shawn or Shannon posted that for me and now I can't find the link.

As you can see, the 11.6 starts at WOT when I jump on it at 2,000rpms and climbs until I hit about 3,500, then it stays above 12, up to about 12.3. Erik has another video that will show it better, but I haven't seen it yet. It is much better than before, when I was at 10.0 all the way through.

I also want to add the triple heat shield before the next run, because my rear carb runs 25-30 degrees F hotter than the other two and it is set to run richer than the others to keep it from starving when hot.

The next time, I will have a video camera on the computer screen to watch the entire process. This is really the fun part after all of the BS work is finally done.
 
Paul, The needles that I am using are B1CE's, from Joe Curto.

Was that Autocross TR6 Bob Lang's?
 
Thank you Shawn. I am adding that number to my parts list right now.

That car ran after lunch, so I didn't get to meet the owner or see it run. Erik gave me the pictures and feedback because he stayed all day and I had to leave at 11AM.

I think there will be more pics up on the Boston MG Club site soon, as they were the sponsor for this event.
 
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