[Tandyman]

Nicks Garage posted a 455 dyno video today .

https://www.youtube.com/watch?v=hYIJ8JxNScE

Glenn

[slowbird]

Not sure I'd let him touch an engine of mine.

[mgarblik]

I watched most of the video. It was interesting to me because that's the exact same dyno set-up we have at my school. It's an older Superflow SF-901 with the 30K hardware and software update. The biggest difference is we prefer to use an air flow hat (meter), and fuel flow meters to get direct BSFC numbers rather than a calculated air and fuel usage based on wide band O2 numbers. Both are useful. But when he kept mentioning over and over the carburetor was too small, that can be verified much more easily with actual consumption numbers. Also, just having a vacuum gauge on the intake would indicate a very small carburetor. Of course we know the Q-jet was rated at 750 CFM or 800 CFM. If he was so sure the carb was too small, we keep a Holley " dyno carb" on the shelf. It works damn good on any engine we put it on, just for a baseline comparison. If I am sure the carb is an issue I throw that Holley on and make a pull. You just never know till you test. A Q-jet can look great and be down 20-30 HP vs the dyno Holley or be 20-30 HP better. I have seen it go both ways. Just nice to have a baseline handy. Had a 383 Mopar on the dyno a couple months ago and it just wouldn't make the peak HP we anticipated. Was down about 30 HP. Had an Edelbrock AFB knock-of carburetor. We installed the largest jets and smallest metering rods we had available and it came up 11 HP peak. Threw the dyno 750 4150 carb on it and it made an additional 18 peak HP and 12 ft. lbs. of peak torque. You just never know till you try. I wish Nick would have told us specifically what cam was in it and exactly what timing he ended up with. The only other thing we do differently is I like to throttle back manually at the end of the pull rather than have the dyno servo do it. He let the dyno pull back on the load for 2-3 seconds. That's a little hard on a new engine IMO. Overall, fun to watch.

[Mike Davis]

Mike, I think the cam he stated was a Lunati VooDoo 702. 219/227@050, 468/489 lift. 112LSA
When he said the carb was too small, I wondered why he didn't pull it off and check the secondaries to see if they were opening all the way.
I think a stockish 455+.030 with that cam and with RA manifolds vs logs should be a little closer to 400HP.

[dragracerx2813]

Most of the videos I have seen him do, have all been pretty mild set ups.

[TCSGTO]

I noticed he runs most of his tests at 180 water temp to give a more real world number for a street car. Didn’t see the video so I don’t know if that’s what he did here.

[mgarblik]

If we have someone who is "racing the dyno" for bragging rights, best peak HP numbers for us come with a water cooling tower temp of 130-140 F. There is also the "Happy Knob" under the control console where you can "dial in" an additional 25-35 HP. It's supposed to be used for calibration, but you know how that goes. We calibrate our load cell with certified weights every 4-5 engines we run and get get it +- 1 ft. lb. Our dyno is generally considered pretty conservative whenever people bring us dyno results from other places. Our chassis dyno is nicknamed the "Heart Breaker". Had a student with a "souped up Honda " 1.6 liter engine! Cold air intake and a "can on the exhaust". Made peak HP at the wheels of 37 HP, but a hell of allot of noise. Thus the "Heart Breaker". Also had a 75 Grand Ville on the same dyno. 455 4BBL. Sounded good, seemed to run fine. 132 HP at the drive wheels. That's all folks. The "Heart Breaker" struck again!

[Stan Weiss]

Originally Posted by mgarblik

I watched most of the video. It was interesting to me because that's the exact same dyno set-up we have at my school. It's an older Superflow SF-901 with the 30K hardware and software update. The biggest difference is we prefer to use an air flow hat (meter), and fuel flow meters to get direct BSFC numbers rather than a calculated air and fuel usage based on wide band O2 numbers. Both are useful. But when he kept mentioning over and over the carburetor was too small, that can be verified much more easily with actual consumption numbers. Also, just having a vacuum gauge on the intake would indicate a very small carburetor. Of course we know the Q-jet was rated at 750 CFM or 800 CFM. If he was so sure the carb was too small, we keep a Holley " dyno carb" on the shelf. It works damn good on any engine we put it on, just for a baseline comparison. If I am sure the carb is an issue I throw that Holley on and make a pull. You just never know till you test. A Q-jet can look great and be down 20-30 HP vs the dyno Holley or be 20-30 HP better. I have seen it go both ways. Just nice to have a baseline handy. Had a 383 Mopar on the dyno a couple months ago and it just wouldn't make the peak HP we anticipated. Was down about 30 HP. Had an Edelbrock AFB knock-of carburetor. We installed the largest jets and smallest metering rods we had available and it came up 11 HP peak. Threw the dyno 750 4150 carb on it and it made an additional 18 peak HP and 12 ft. lbs. of peak torque. You just never know till you try. I wish Nick would have told us specifically what cam was in it and exactly what timing he ended up with. The only other thing we do differently is I like to throttle back manually at the end of the pull rather than have the dyno servo do it. He let the dyno pull back on the load for 2-3 seconds. That's a little hard on a new engine IMO. Overall, fun to watch.

Unless I am reading the dyno sheet wrong. He did and it does to me show to small a carb.

Stan

[mgarblik]

Sorry Stan, I did not catch that. Yes, pulling 1.5" average through the pull does indicate a restriction, carb. being most likely. Is the intake they were running one with the secondaries partially blocked off by the casting on the secondary side? That might do it.

[Jay S]

I like Nick’s garage. Things don’t always go as planned, and he works thru it until he gets close to the results he is looking for. You could see the shot of the secondary air door when he went full throttle, didn’t appear the air door opened to the straight down position to me. It would have made bigger numbers with that small adjustment on the secondaries and probably needed to be running an air cleaner for it to make closer 400hp with the qjet. Both those things together likely made the carb appear to small on the dyno pulls. Jmho, it made about what you would expect with that small cam as it was setup without much tuning.

[Stan Weiss]

He said it was a factory cast iron manifold. Is it a full dual plain? I have found that dual plain manifolds like a little larger carb than when using a spacer or a single plain wants.

Stan

[maxpowerta]

I really didn't think those numbers were too far off for a stock headed, relatively mild cammed engine, It will certainly make for a stout street engine.

[GTOLou]

I think ? 64 heads. Compression he stated at 9.7:1.

Just leaving power on the table with the 219intake cam. Heck, might even run a tad hot with a small cam and decent compression.

Unless you are using the motor to tow with - I just cannot see going smaller than 230 on the intake with a 455. It'll still pull way over 15 of vacuum and idle at 800.

Color wrong for 76 TA motor too.

I do like NIck's video's. I'm sure dude has forgotten more than I'll ever know.

[rwfisher]

Another enjoyable Nick’s video with a “Hotter” 455 build.. Decent numbers in the end.

https://m.youtube.com/watch?v=sWcDo3...oFX3Cm5J2Xqjag

[Gary H]

It looked like cast number 96 heads on it which are big valve 71' 400 heads. They have 96 CC chambers and 2.11 1.77 valves. I would think he's closer to 9.5 CR but it all depends on the specific pistons deck height etc.

[ponjohn]

His engines always seem to down on power.

[ZeGermanHam]

He seems to do mostly stock or close to stock builds. And in this case, he said the owner supplied the parts, so whatever performance shortcomings are present can probably be attributed to the owner rather than Nick.

[NeighborsComplaint]

Originally Posted by ponjohn

His engines always seem to down on power.

Real-world numbers from a stock engine (that cam cam in a 455 does not qualify as a performance cam), how refreshing! BTW, he checked for full mechanical secondary operation and the air valve was open as far as the engine required. It looked vertical to me.

The aftermarket Distributor I was likely out of the box curved but he did check multiple times for mechanical advance only and total advance.

[Jay S]

Not that this matters much. Here is a screen shot of the carb at the top end of the pull when the carb was wide open. Looks like most qjet’s I have had before I made them open a little more, I set them so the leading edge is straight down.

I thought the top view camera shot was cool to watch the air valve pulse as it opened on the pull.

[77 TRASHCAN]

I wonder if Nick built the engine??
Another 455 with too small of a cam, leaving a bunch of power on the table. Sorry I don’t have any inter web comparisons for us, I just trust Cliff’s years of labor.
The other 455 he dyno’d was a lot stronger, and had 2 AFB’s on it. It was also sporting stock stamped rockers..........

Throw a 041 cam in it, degree it....