Nicks Garage 383 build

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Apparently there are lots of people patiently waiting for Nick's: Part - 3 Video.

6,000 views in just 10 days.

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Too much cam, too low of compression with the previous odd .020 over pistons that were re-rung, sunken valves in the head's recent valve job. Mismatched intake to head ports, after milling heads down .020 ths and using the thinner. 020 ths tin head gaskets???
(.040 port alignment issue?)

Possibly all of the above? Patiently waiting for the next Video.....

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☆☆☆☆☆
 
BSB67 said:
Wonder how it would respond with opening up the MABs and playing with the jets accordingly.
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There is no doubt that the dyno carb was very rich, and if I was just after horsepower numbers, changing jets or air bleeds would have definitely improved things, but my main goal was dialing in my own carb.
 
There was a SB stroker here a few moths ago that was built with some old EQ magnum heads and a Comp XE285HL cam.
It was just here for the dyno work.

The owners 850DP carb had huge jets in it and was super rich(10’s).
After a couple of rounds of jet changes it was into the normal a/f range…….which was worth some power.

The bsfc numbers at peak power went from .59 down to .49, the fuel flow went down about 30lbs/hr, and the a/f ratio went from 10.8 to 12.4.

After the jet changes, the TQ went up 10 and the HP about 20.

I guess what I’m saying is, with a 750dp carb, tuned to deliver hi-12/low-13 a/f ratios…….I can see the hp numbers on qkcudas 406 going up 10 or so.
 
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I think the Pontiac enthusiasts missed the point of that story……..and that the motor in question was not a SD that was getting a rebuild.

It was a bread and butter 455 that the owner wanted built to the 500hp mark.
Shop A failed the test with a 315hp effort.

My question to the installation shop was, why did the owner accept it like that?
Nothing about the build was what he had asked for.
When the builder showed him the dyno sheet, the owners response should have been, “call me when you find the missing 150hp”.
 
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PRH said:
I think the Pontiac enthusiasts missed the point of that story……..and that the motor in question was not a SD that was getting a rebuild.

It was a bread and butter 455 that the owner wanted built to the 500hp mark.
Shop A failed the test with a 315hp effort.

My question to the installation shop was, why did the owner accept it like that?
Nothing about the build was what he had asked for.
When the builder showed him the dyno sheet the owners response should have been, “call me when you find the missing 150hp”.
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I don't get how you can only get 315 out of a 455.. i don't like pontiacs but they can make power.
 
RAMM said:
400 is the same slug as the 383 should run even worse with a dumpr cam. I never built a 2bbl bigblock so? J.Rob
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AS RAMM told me one time when I was at his shop the 383/400 has no piston speed with that short stroke, it needs to BUZZ to make great power. BTW J.Rob has done many many engines and with great results Keep up good work J
 
Icetech said:
I don't get how you can only get 315 out of a 455.. i don't like pontiacs but they can make power.
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Richard Holdener did a low cr 440 with 4bbl headers and mild cam made like 330 hp if I remember right, it wasn't a rebuild though, it was a motorhome 440 from the road kill guys.
 
PRH said:
I think the Pontiac enthusiasts missed the point of that story……..and that the motor in question was not a SD that was getting a rebuild.

It was a bread and butter 455 that the owner wanted built to the 500hp mark.
Shop A failed the test with a 315hp effort.

My question to the installation shop was, why did the owner accept it like that?
Nothing about the build was what he had asked for.
When the builder showed him the dyno sheet, the owners response should have been, “call me when you find the missing 150hp”.
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Just FYI, I'm not a Pontiac enthusiast, and I understood that the 455 you worked on was not the SD version.

I'd also point out (not to you, but to some of the others) that a motor will make more power on an engine dyno with no accessories and dyno exhaust than it will make in the car with all accessories, engine driven fan, full exhaust system, hot underhood air, etc. Essentially, the difference between gross and net horsepower. So the 310 net horsepower SD 455 was a lot stronger than the non-SD 455 that made 315 on an engine dyno.
 
Icetech said:
I don't get how you can only get 315 out of a 455.. i don't like pontiacs but they can make power.
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I've never been a fan, either, but you're absolutely right. They can.
 
273 said:
That's crazy to miss the mark by that much, how could that be possible even with a limited knowledge of performance engines.
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I can only theorize…….
The builder had it in his head how he was going to build it…….and basically disregarded the owners requests.
Now, keep in mind I’ve got one side of the story, but both the auto shop and engine owner seemed to be on the same page about the goal being 500hp.
I never spoke with the builder about it.

But, fundamentally………nothing in the build was geared towards a target of 500hp.
Stock cast rods, stock replacement style cast pistons, late model smogger heads with zero porting, low CR, small cam, small intake, small carb……..that doesn’t all add up to big hp.

I know the builder, and if he really had “500hp” in his sights, I’m sure it would have been a lot closer to that mark.

Nonetheless, it left his shop with a sheet from his dyno showing about 340hp, which I was not able to duplicate on the dyno I use.
 
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m79ded said:
it needs to BUZZ to make great power.
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Fact is, all short stroke engines need to spin to make power. The sweet spot is between 5500- 7000 rpm or higher depending on compression ,cylinder head, intake and camshaft.
 
PRH said:
Nonetheless, it left his shop with a sheet from his dyno showing about 340hp, which I was not able to duplicate on the dyno I use.
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With the same EXACT engine. Befuddling for sure.
 
The real question is……

Has Nick bothered to lurk on here to check out the buzz about his video?:eek:
 
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RustyRatRod said:
With the same EXACT engine. Befuddling for sure.
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Not at all…..to me at least.

I say it all the time…….you can’t(well….”shouldn’t”) directly compare results from different dyno services.

We see it often……..engines tested at another shop……..and then when we test it the numbers are pretty far off.
 
PRH said:
Not at all…..to me at least.

I say it all the time…….you can’t(well….”shouldn’t”) directly compare results from different dyno services.

We see it often……..engines tested at another shop……..and then when we test it the numbers are pretty far off.
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That's very true. With chassis dynos as well. Did they include which corrections and such they used? That can have a huge impact as well. The only hands on dyno experience I have is decades old back in school when our auto shop class was able to use the dyno at Mercer University in Macon. After that, since we were "kinda somebody" and knew those at the school in charge, we were able to dyno several of our own engines while learning a little something, even though were were not enrolled at Mercer. There are SO many variables that you can take a 250HP engine and make it seem as if it produces 500HP. I guess what I'm trying to say in a nutshell is, you need to KNOW what you are doing to operate a dyno correctly.
 
A dyno should be able to accurately measure the engines torque @ rpm ?
I could see the circumstances that torque is being created under from one dyno to the next eg.. air, oil, water, temps etc.. might not be the same accurate condition for different engine output.
 
I guess what I'm trying to say in a nutshell is, you need to KNOW what you are doing to operate a dyno correctly.
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Doing my best to not sound like I’m full of myself……..I feel I’m in that category.

The engine shop where I tested that Pontiac, I probably did the testing for 75% of the engines that got run on that dyno for 8 years.
 
PRH said:
Doing my best to not sound like I’m full of myself……..I feel I’m in that category.

The engine shop where I tested that Pontiac, I probably did the testing for 75% of the engines that got run on that dyno for 8 years.
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Oh I was in no way implying YOU didn't know what you are doing.
 
RustyRatRod said:
That's very true. With chassis dynos as well. Did they include which corrections and such they used? That can have a huge impact as well. The only hands on dyno experience I have is decades old back in school when our auto shop class was able to use the dyno at Mercer University in Macon. After that, since we were "kinda somebody" and knew those at the school in charge, we were able to dyno several of our own engines while learning a little something, even though were were not enrolled at Mercer. There are SO many variables that you can take a 250HP engine and make it seem as if it produces 500HP. I guess what I'm trying to say in a nutshell is, you need to KNOW what you are doing to operate a dyno correctly.
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The only way that can happen is if the dyno operator is an idiot or a liar.

If you are using the same correction factor (and is should be STP and not the newer factors) there shouldn’t be 10 hp difference from corner to corner of the country.
 
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