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Sharkfest update, got on the dyno today

JHL

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Chris

The problem I had both times I had my 81 on the rolling road was tyre slip. The rollers were very smooth and on one run the tyres were beginning to smoke a little !!! so it never showed it`s true potential. I think they are a good tuning tool but not the most accurate way to determin horse power. Did it have a calibration cert ???

J.
 

69MyWay

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JHL said:
Chris

The problem I had both times I had my 81 on the rolling road was tyre slip. The rollers were very smooth and on one run the tyres were beginning to smoke a little !!! so it never showed it`s true potential. I think they are a good tuning tool but not the most accurate way to determin horse power. Did it have a calibration cert ???

J.

It is funny you mention that, because although my rear tires are massive in width (contact patch is just over 12" per tire), there was quite a bit of black rubber dust coming off the tire area, and I could smell the rubber. Several people made the comment that the tire sound alone while I was spooling up the dyno machine was louder than most cars there (plus the exhaust was loud of course).

At one point, I felt like something was a miss. In other words, I got the sensation that the car was floating and I wondered if my clutch was slipping or if the tires were kind of lifting off the roller wheels.

Was the machine calibrated/certified, I have no idea?

I did blow chunks of fiberglass out of the side pipes onto the crowd. That was kind of funny. One guy there said he thought I had sucked a low flying bird into the engine!
 

JHL

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I did blow chunks of fiberglass out of the side pipes onto the crowd. That was kind of funny. One guy there said he thought I had sucked a low flying bird into the engine!

On my first visit there was a Porsche Turbo Cup race car on the rollers in front of me and when they backed of the gas there was two huge flames shot out of the exhausts. I was suitably impressed.

Back to yours though, when you think of the contact patch of your tyres on the road compaired to what it is on the rollers you can see how your torquey Big Block would easily lose there grip even with the size of your tyres.

J.
 
R

RalleyRed

Guest
I wasn't going to post any numbers until I got to another dyno myself.
Unfortunately the closest one to me is at least 3 hours away. I will make the trip I just don't know when I'll be able to.

Now for those of you that don't know, I've got the 385 FastBurn which I upgraded to the spec's of the ZZ430. It's supposed to be 430hp/430ftlbs. concidering the accepted 20% drivetrain loss I should have roughly 344hp/ftlbs.
On this dyno I showed only 262hp and 327ftlbs.
That's about a 40% loss. Now either the dyno is wrong or GM is getting a call from one ****ed off customer.:mad

Rick
 

Evolution1980

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Rick,

Chill... that dyno was waaaaay off. GM isn't misrepresenting. That's Ford's job....
 

Evolution1980

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69MyWay said:
Let's see if this works.

Ahh... I see we gots ourselves a wiseguy in our midst... :SLAP
 
R

RalleyRed

Guest
Andre,

I know the dyno numbers were a bad joke, I only have to push down that go pedal to feel a bit more than the dyno showed.

Rick
 

Stingray6974

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C'mon Chris,
At my age I can barely see the screen much less those numbers. It looks like the fine print on an insurance contract:L

Mike
 

Baldie88

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Nothing to be ashamed of

I may be old and my glasses have cheaters in them but a little fooling around with Chris's dyno ticket and I could make out what I think is max hp and torque. I would give away your secret Chris since it was still hard to see even after I fixed it but it definitely puts my stock 88 to shame. You've got one awesome car and if you ever decide to get rid of it for some reason, give me a call (although it's probably like giving away your first born!). :)
 
S

sscam69

Guest
Hey Chris

What were you shooting for? Are you thinking about swapping out the cam, or are you going to take it to get redynoed first?
 

69MyWay

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sscam69 said:
Hey Chris

What were you shooting for? Are you thinking about swapping out the cam, or are you going to take it to get redynoed first?

I have no plans on swapping the cam at this time. I want to first make sure/determine where and why the base line is where it is on my ride vs. the adverstised potential of this engine package.

You see, this is poetic symbolism. That is, my dyno image is just as small as compared to what you would prefer to see, as my actual numbers where in comparison to what I wanted to see. Actually though, I can't really figure out how to use my scanner and create images that are any bigger.

I duplicated to the last detail Edelbrocks 539 hp test mule. That is the RPM Heads, Cam, Crane Gold Series Rockers, Speed Pro pistons, ring gap, main and rod clearance, .060 over bore, header diameter (well very close at least), RPM cam, and topped it off with the Air Gap manifold and the EFI conversion.

I had thought worse case scenario that she would pull in the very high 300's or low 400's at the rear wheels, and best case to be at the high 400's to a possible extremely low 500 hp at the rear wheels. So, you can see how (if you can read the dyno print) what a shocker it is to be so far off!

Is this an embarrasement? Yes! Add up what I spent buying those parts and you will find I spent a freakin fortune to make no more power than a very hot small block!

I just can't imagine where I went wrong, or if the dyno is off, where is it off, and by how much. My guess is at least 100 hp off. If that is the case, then I am just bumping the low end of the range I thought I would hit on the worse case scenario. Which means it is still a BIG dissapointment.

So, how do you deal with this? I actually made Nikki a promise to let the car rest for a while now that Sharkfest is over. So, to vow true to my words and respect for her request, Killer sits out in the garage right now collecting dust. To add insult to injury. Sitting out in the hot sun over the labor day weekend appears to have caused my bonding agent on the front inner fenders to reactivate to some degree and create a distoration on the outter surface of the front fenders! I first noticed it getting the car off the trailer back in Florida on Monday afternoon. The only solution I see is to block the nose of the car back down and reshoot it!

Here is the dyno curve from the test mule at Edelbrock. Only difference being this is at the flywheel, and it is a carb and carb intake vs. the Airgap and EFI

7161hp.jpg


Here are all the specs, which are near identical to my engine.

Edelbrock Performer RPM Power Package Components for
454 c.i.d. Chevrolet:

Edelbrock Performer RPM 2-O intake manifold..........................#7161

Edelbrock Performer RPM camshaft kit.................................#7162

Edelbrock Performer Series carburetor (750 cfm, manual choke)........#1407

Edelbrock Performer RPM aluminum cylinder heads......................#6045

Edelbrock timing set.................................................#7810

Edelbrock valve springs

(supplied with Edelbrock Heads; iron heads use #5762)................#5745

Edelbrock retainers

(supplied with Edelbrock Heads; iron heads use #9731)................#9715

Edelbrock valve locks

(supplied with Edelbrock Heads; iron heads use #9612)................#9615



Shortblock Components:
Bore........................................................4.250" + .060"

Stroke......................................................4.000" (stock)

Crankshaft............................................factory forged steel

Rods.........

factory (polished and shot peened) 6.135"center to center with ARP bolts

Pistons.................................................TRW #L2399 + .060

Rings......................Speed-Pro #R9590 + .065, 5/64" x 5/64" x 3/16"

Head Gaskets................................................Fel-Pro #1017



Test Engine Specs:
Main Bearings (clearance)...........Michigan 77 #MS 829 H (.0026"-.0035")

Rod Bearings (clearance)............Michigan 77 #CB 743 H (.0022"-.0025")

Piston Wall clearance............................................. .0065"

Ring End Gap clearance.................top ring .018" - second ring .014"

Rod Side clearance................................................. .020"

Compression ratio...................................................9.6:1

Ignition and timing...........................36° @ 3000 RPM + MSD 6 A box

Headers.............2-1/8" Primary, 32" long - collector 3-1/2"- 10" long



Edelbrock Performer RPM Aluminum Cylinder Head Specifications
Intake port volume..................................................290cc

Exhaust port volume.................................................100cc

Combustion chamber size.............................................110cc

Crane roller rocker arms.........................................13750-16

Intake valve size..................................................2.190"

Exhaust valve size.................................................1.880"
 

69MyWay

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1969 Killer Shark
Okay, here is my tiny little power graph. Notice how I start out at 2,500 RPM in line with what you would expect with a drive train loss along with the specs of the Test Mule engine. Then, she falls flat on her face.

attachment.php
 
L

Ls1smlblck

Guest
Well that sucks arse! Did you call Edelbrock up to see whats up? :eek:
 
S

sscam69

Guest
Damn Chris

I can see why your upset now. I know this isn't your first build, thats something I would expect, so something's amiss here. Thats a lot of power/torque your either loosing or your not getting.


Hmmm.....think...think....think Is the A/F ratio between 12.5-13.0, and there shouldn't be anything restricting air to the engine right. I remember you mentioned that you could hear the air being sucked in.

IMO I would expect to see at the very least 475rwhp:J . I have the same question as LS1smllblck, have you called Edelbrock because the things mentioned above would only cause small power losses, not close to 200rwhp.

I would say get the thing redynoed somewhere and then call up edelbrock. But thats just what I would do.
Believe me even I'm:mad :mad :mad :mad
 

69MyWay

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Auburndale, Florida
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1969 Killer Shark
Just talked to the local tuner with the Chassis dyno.

At this point in time I am going to "assume" I have screwed up the tuning on the car and go from there.

It boils down to $150 per hour to the local shop to set up with a seperate air/fuel meter, dyno time, and expert advice from the local tuner to try to squeeze whatever this package is willing to give up.

So, since my budget is broke right now, I think this will be on hold for now. They did tell me that mobile dynos differ significantly, and that the dyno operator can pretty much make the dyno produce whatever numbers they want with a few calibration changes.

The shop that I am considering claims to put over 600 hp out of ported and polished iron head big block engines. The only bad part, they seem to not like anything made by Edlebrock, so it could turn into a "well, we could make power here, but you are running that Edelbrock junk" type response, and or, "if you let us port and polish those heads, grind a cam, etc. we can get xxxx hp".

I am not interested in getting into that "he said, she said, but I can sell you a ....." game.
 

Evolution1980

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69MyWay said:
...so it could turn into a "well, we could make power here, but you are running that Edelbrock junk" type response, and or, "if you let us port and polish those heads, grind a cam, etc. we can get xxxx hp".

Oh, you mean, just like Breathless Products was doing at the dyno pull in BG??? :L :L

I'd say have it dynoed at different places and take the average. If someone wants (example) $75 for 3 pulls, would they allow 1 pull from 3 different cars? I'd like to know what my numbers are, but I don't need three pulls to do it. Maaaybe two to assure consistancy. If they allow different cars, just find two other people to split the cost!

On the other hand, Chris, you know you have a badass car, it won at BG, it's going to be featured, everyone loves the car, etc etc etc... do you even care what the numbers are? You could just let it all slide off your back. (Of course, this is easier said than done :)) I understand wanting to know what you've created. The other option is something like the G-Tech, which measure HP within a couple % of actual RWHP. You can play with that as much as you want! All you need to know is your car's weight. It does the rest.
 
S

sscam69

Guest
I think it comes down to paying for something you didn't get, at least thats my gripe. This hobby is not cheap and when you pay for something and its not what it turns out to be, I would be really upset

:mad :mad :mad

It could be just a tuning issue, but if its not.........
 

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