W2 408 Dyno results today !

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What plug would you choose and how do you determine that ?
I am jumping back in here.
IMO for a plug that has been through multiple dyno passes it looks pretty nice.
True being able to look down in the plug will tell you more at WOT, I use a lighted magnifying app on my phone rather then cutting the plug. As far as heat range we always wanted them burned two threads down, hell you're there.
Comparing the rest of the plugs will give you a bigger picture.
I would not get too wound up about your plugs until you get some street miles on them, as they will change.
I have had really good results with Autolite 63 plugs for the street.
 
I dont plan on changing anything until I have put some miles on the car. But it is good to learn and have conversations about different ideas.
 
I alao meant to check the oil level by removing the overflow plug on the pan but forgot to do it . I am pretty sure I had too much oil in it . I had about 7 qts in the Kevco pan and the dipstick showed full but later I recalled that the dipstick was off a bit. I need to ad 6 qts and drill a small hole in the stick at that point .
Do you have a printout of the oil pressure thru the run?
 
This screen shot has oil pressure on it:

D05E147E-43D9-45B1-A165-6547AA66FF4F.jpeg
 
I was just curious why you came to that conclusion .... I have read up on plug reading but it is not as absolute today with ethanol etc.. I have had plugs that were bright white but the AFR was rich and I could smell the raw fuel. It makes a Dark Art even darker...lol
You can still get a good read on a plug with ethanol in the fuel. Be it e85 or e10 or whatever. The projected tip and what looks like the depth of your plug around the porcelain are what led to my conclusion.
 
This screen shot has oil pressure on it:

View attachment 1715817839
I don't see any evidence of oil aeration from too much oil. Things that I know can cause poor bsfc AND power: terrible port work with poor valve job, wrong cam timing, severe mismatch of parts like small cam and single plane intake, or really big cam and real tiny carb, things like that. Also odd it liked 32....I would think it would want more. Not a lot more, but still a bit odd. Did you happen to change headers at all? Could also be something not right with the carb. When I see things I don't like, I start looking at the easy stuff first, replace the carb with a known or just different carb, etc...
 
I don't see any evidence of oil aeration from too much oil. Things that I know can cause poor bsfc AND power: terrible port work with poor valve job, wrong cam timing, severe mismatch of parts like small cam and single plane intake, or really big cam and real tiny carb, things like that. Also odd it liked 32....I would think it would want more. Not a lot more, but still a bit odd. Did you happen to change headers at all? Could also be something not right with the carb. When I see things I don't like, I start looking at the easy stuff first, replace the carb with a known or just different carb, etc...

I did not change headers. Meant to but forgot to grab them when I left home .
32 seemed to be the number. Run 7 was when we ran it with 36 and it lost power .
 
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do these heads have really efficient Exh ports?
these are closed combustion chamber heads?

one other thing, does you dyno guy have an similar engine combos from his dyno you could compare to?
 
All my testing has been done at an elevation that isn’t very high.
Obviously, if that dyno is at about 2500’, it’s going to affect the uncorrected numbers.
The bmep number is derived from the uncorrected numbers.
They seem on the low side for this build, but that could just be the result of the elevation.

So, a question I would have for the dyno owner is........ how do the bmep numbers from this w2 build........ on that dyno, compare to other 10:1-ish hot street/strip builds he’s tested?

The bmep numbers basically take the engine displacement out of the equation for comparison purposes.
 
All my testing has been done at an elevation that isn’t very high.
Obviously, if that dyno is at about 2500’, it’s going to affect the uncorrected numbers.
The bmep number is derived from the uncorrected numbers.
They seem on the low side for this build, but that could just be the result of the elevation.

So, a question I would have for the dyno owner is........ how do the bmep numbers from this w2 build........ on that dyno, compare to other 10:1-ish hot street/strip builds he’s tested?

The bmep numbers basically take the engine displacement out of the equation for comparison purposes.

Nampa is at 2500 ft and the corrected elevation was 3800-3500 throut the day .
Frank said he was very impressed with the engine. He has had engines up to 1800 hp on it . He really wasnt tuning for peak HP . Was more focused on the low and mid range . He said if this was a pure drag engine he would have only needed to spend a few hours with it. I like that he focused on what I was actually the car for.
That being said I am sure there is still some ponies to be had. And maybe he just has a stingy dyno ?
 
I asked this earlier & didn't see an answer. Was the carb linkage checked to see if the carb was getting WOT???
Not only would total airflow be reduced, but angled t/blades could change distribution, some rich, some lean cyls.
 
I asked this earlier & didn't see an answer. Was the carb linkage checked to see if the carb was getting WOT???
Not only would total airflow be reduced, but angled t/blades could change distribution, some rich, some lean cyls.

Yes it was verified.
 
Just run it 493 ain’t no slouch believe me I was a little disappointed with mine 470 -518 and my engine builder said don’t get hung up on numbers as his dyno was on the liner side mate it still puts a smile on my face still after 15k It pulls this A body with no effort and yours a 4 speed .,Get used to buying Tires. Just driving it in the torque range 4.5 rpm this thing hauls arse with little effort and I’m running 3.45s on a 27 rear tire . It blows me away the throttle response with very little effort . Mine ain’t no strip car just a hot streeter with good road manners A904 mvb.
 
No dyno guy ever said “hey, my dyno reads a bit hot so don’t worry about the numbers”. Everyone always has a stingy dyno when the numbers don’t meet expectations. I was watching a BBC on a chassis dyno...must have been 2006 or so. Anyway, it was on the dyno for hours and they beat 985 crank hp out of it. Single 4, 572 inches so that was pretty good. And that was in the guys car, with his headers, ignition and all that. The dyno guy was getting tired of all the bitching by the car owner so he said “I’m going to make a major tuning change, and if it works it will make a big number and if it doesn’t it’s tapped out”. They made 3 more pulls and boy howdy, there it was 1020-1030 on the three pulls. The owner was ecstatic that his stuff went over 1000 hp on a single 4. While they we loading the car up I asked the dyno guy what the big change was to get that power. He said I didn’t change a damn thing. That was as good as it was going to get. I just adjusted the correction factor in the software to shut him up and make him happy. I suppose it happens more often than not.
 
Sometimes you just give the ***** what they want and send them on their way. It's better then punching them in the face, well most of the time!

Jeff
 
493 hp is more than I will ever need on the street but that doesnt mean I am not interested in understanding why it fell off so abruptly after 6k and how to stabilize the cyl to cyl AFR and the lower rpms. And how will the tunnel ram effect it . That will be interesting .
 
You should be happy, I have a little over 400 HP in a 1970 340 dart and am very happy. You should be wondering why certain things didn't go as you thought they should have, if you don't find out why it'll drive you nuts.

Jeff
 
One thing that occurred to me is that we tend to focus on the data from these dyno runs and base all our decisions on wide open throttle pulls rather than part throttle exceleration
or cruise . And in retrospect I realize that Frank spent quite a bit of time doing just this before we ever did a full pull .
 
One thing that occurred to me is that we tend to focus on the data from these dyno runs and base all our decisions on wide open throttle pulls rather than part throttle exceleration
or cruise . And in retrospect I realize that Frank spent quite a bit of time doing just this before we ever did a full pull .


I agree with how and what you did. But I wouldn’t do the one to the exclusion of the other. Another way to say this as bad as the numbers look (bsfc for one and it would nice to see the bsac numbers too) it would have been nice to spend some time cleaning up those numbers. I would have started by looking at the plugs after a wot pull and made some decisions based on that. I know dyno time is expensive and it flies by so fast you can’t believe it. I’m just a let’s clean it all up kind of guy. I don’t think a sacrifice needed to be made for cruise and part throttle or wot. I think that is where most of us are at. Just looking at the bsfc numbers means that somewhere there is power left, and I suspect it will show up in part throttle and cruise too.
 
How much is a dyno day on that side of the puddel?
I see you get quite much more data from your session that i did over here.
 
In Canada I pay the guy $500… sometimes we have the engine on all day…. Last engine I did was on the dyno for maybe 40 minutes and about 6 pulls before we called it good… my friend is about to dyno a EFI pro charged small block dodge and has the dyno booked for a month…
 
How much is a dyno day on that side of the puddel?
I see you get quite much more data from your session that i did over here.

The SF-902 they used for that session looks to be very well equipped.

Although I’m still surprised they didn’t use an air flow sensor.
 
In Canada I pay the guy $500… sometimes we have the engine on all day…. Last engine I did was on the dyno for maybe 40 minutes and about 6 pulls before we called it good… my friend is about to dyno a EFI pro charged small block dodge and has the dyno booked for a month…


If your friend is going to test a lot of different things, a month isn’t really all that long. Of course, if all goes well it may not take that long.
 
No dyno guy ever said “hey, my dyno reads a bit hot so don’t worry about the numbers”. Everyone always has a stingy dyno when the numbers don’t meet expectations. I was watching a BBC on a chassis dyno...must have been 2006 or so. Anyway, it was on the dyno for hours and they beat 985 crank hp out of it. Single 4, 572 inches so that was pretty good. And that was in the guys car, with his headers, ignition and all that. The dyno guy was getting tired of all the bitching by the car owner so he said “I’m going to make a major tuning change, and if it works it will make a big number and if it doesn’t it’s tapped out”. They made 3 more pulls and boy howdy, there it was 1020-1030 on the three pulls. The owner was ecstatic that his stuff went over 1000 hp on a single 4. While they we loading the car up I asked the dyno guy what the big change was to get that power. He said I didn’t change a damn thing. That was as good as it was going to get. I just adjusted the correction factor in the software to shut him up and make him happy. I suppose it happens more often than not.
These guys I know well & his statement was months before my engine made it into the dyno room . These guys build pretty exotic engines for the dirt track community and are down to to earth no bullshit type of people who do great machine work and engine building . True there are types out there expecting really big numbers and ***** about it so the op got sick of hearing his crap so he made a few tweaks to get him out in my situation my cam choice could have been better but it ain’t no strip car but I’m happy with how to turned out in the end .
 
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