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Dyno pull feedback

Posted By: MikeyT

Dyno pull feedback - 05/14/10 12:19 PM

Hi all

I just wanted to get your feedback on my build and give me some pointers on where I should go from here. This was my first trip to the dyno, so I didn't know what to expect. First off here is the mill

440 bored .40 over total cubic inches are 448
set of stock aluminum 440 source heads
1.5 stock rockers
comp xtreme cam XE268H 480 lift .050 224degree/230 degree
Holley Street Dominator intake
headman shorty headers 1 3/4" at 2/5 inch collectors
800 cfm Thunderseries edlebrock carburator Jetted up 2 sizes
3860 lbs with me in it.




hp 304 and torgue at 416.

A couple of nice things about the graph. I have a very nice broad power band it arches well between 4600 and 5400 rpms. As is a rule my 440 is a torque monster. It seems to make my Converter flash about 3300. The torque band is pretty impressive and remained high through the whole run. Now we are going to continue to work on this a bit. The guy who runs the dyno has a father who is a carter expert and he is going to look at it as well as take some time to adjust timing with it and we will do it again. For the most part, I was hoping for more, but am satisfied for what the engine is, which is a mildly built big block car.

Mike
Posted By: B1Fish540

Re: Dyno pull feedback - 05/14/10 01:08 PM

Those look like good real world numbers. You bascily have an extra hot 440 Magnum thanks to the Steath heads and warmer cam. You could always step up to cam over .500 lift and a good 850 double pumper that would get you closer to 500 HP.
Posted By: JohnRR

Re: Dyno pull feedback - 05/14/10 03:50 PM

oops it's an automatic .

You have what appears to me to be about 100hp of drivetrain loss .

What work was done to the heads , if any ?
Posted By: MikeyT

Re: Dyno pull feedback - 05/14/10 11:25 PM

no work done to the heads, out of box put them on the car. 100 hp loss of the auto (gasp) really?

Mike
Posted By: 1badx

Re: Dyno pull feedback - 05/14/10 11:33 PM

I would say that is a very respectable HP number for your combination. Considering it was done on a Mustang dyno and assuming all of the loading information was properly entered by the dyno operator I would be very pleased with your power output. As far as drivetrain losses with an automatic and either an 8 3/4 or a Dana we have been seeing around 20-25% in the horsepower range you are in.

Congratulations! Have you had your car to the track yet?
Posted By: MikeyT

Re: Dyno pull feedback - 05/15/10 05:50 AM

Thanks Mike for the perspective. My buddy Nate ran the set up and he has bee doing it for year so I think it was a good set up, my only question is weight, what if the car weighs a little bit more then the 3860 lbs listed?

Mike
Posted By: BSB67

Re: Dyno pull feedback - 05/15/10 10:14 AM

For what you have, I think those are good numbers. Did you have an et and mph goal?
Posted By: 440Jim

Re: Dyno pull feedback - 05/15/10 11:09 AM

The next time you get on the chassis dyno, have them put a wide band oxygen sensor in the tail pipe. That will help you tune the carb.
Posted By: JohnRR

Re: Dyno pull feedback - 05/15/10 12:15 PM

Quote:

Thanks Mike for the perspective. My buddy Nate ran the set up and he has bee doing it for year so I think it was a good set up, my only question is weight, what if the car weighs a little bit more then the 3860 lbs listed?

Mike



The dyno doesn't care how much the car weighs , weight only comes into play for dragstrip calculations.

Considering the heads were run out of the box I guess that's not a bad HP number .
Posted By: MikeyT

Re: Dyno pull feedback - 05/15/10 02:36 PM

Quote:

For what you have, I think those are good numbers. Did you have an et and mph goal?



My hope is to get solidly into the 12's. This might not happen, but last fall I had one run of 13.68 at around 105 mph, yet that was with 3:91 gears in it. This pull was done with the 3:23's in it.

However looiking at it, it seems like 3:91's are the best gear for me, because I would cross the traps at between 5400 and 5700 rpms.

The car fills like it might even like more jetting, it took the largest ones I had in the Eddy kit.

Yet, fuel seemed good most of my pulls put 02 at 12.5 and at top point 14.1 AFR with it averaging out to be 13.1 AFR across the whole run, so perhaps a little more tweaking is in order!@

Mike

PS for the record this engine performaed with the timing set at which is 16 initial and 36 total all in at 2800 rpms.
Posted By: 451Mopar

Re: Dyno pull feedback - 05/15/10 02:50 PM

Is that the real un-corrected power numbers or the SAE corrected power numbers? Anyhow, it looks good considering how small the cam is for that combination.
Posted By: MikeyT

Re: Dyno pull feedback - 05/15/10 03:23 PM

Quote:

Is that the real un-corrected power numbers or the SAE corrected power numbers? Anyhow, it looks good considering how small the cam is for that combination.



LOL, I alwaysd thought it was a nice middle sized cam, I guess not!! I'm not up on my dyno lingo,but I beleive uncorrected power numbers. I know it was 70 degrees out and not overly humid for the day, but I can't give you humidity stuff.

Mike

Mike
Posted By: B1Fish540

Re: Dyno pull feedback - 05/15/10 03:37 PM

Quote:

Quote:

Is that the real un-corrected power numbers or the SAE corrected power numbers? Anyhow, it looks good considering how small the cam is for that combination.



LOL, I alwaysd thought it was a nice middle sized cam, I guess not!! I'm not up on my dyno lingo,but I beleive uncorrected power numbers. I know it was 70 degrees out and not overly humid for the day, but I can't give you humidity stuff.

Mike

Mike



Mike another option would be to swap in some 1.6 ratio rockers ...that would give you over .500 lift w/your present cam. Better yet would be the .509 cam with 1.6 rockers for around .535 lift. Then , you would be letting those heads work and gain about 50 hp. 440s like to breath, thats why the Holley 850 db would be the "best" choice.
Posted By: dirtybee

Re: Dyno pull feedback - 05/15/10 06:26 PM

Quote:

Quote:

Thanks Mike for the perspective. My buddy Nate ran the set up and he has bee doing it for year so I think it was a good set up, my only question is weight, what if the car weighs a little bit more then the 3860 lbs listed?

Mike



The dyno doesn't care how much the car weighs , weight only comes into play for dragstrip calculations.

Considering the heads were run out of the box I guess that's not a bad HP number .



the one time i went on a chassis dyno the operator had to enter the vehicle weight maybe some are different
Posted By: BSB67

Re: Dyno pull feedback - 05/15/10 10:08 PM

Quote:

Quote:

For what you have, I think those are good numbers. Did you have an et and mph goal?



My hope is to get solidly into the 12's. This might not happen, but last fall I had one run of 13.68 at around 105 mph, yet that was with 3:91 gears in it. This pull was done with the 3:23's in it.

However looiking at it, it seems like 3:91's are the best gear for me, because I would cross the traps at between 5400 and 5700 rpms.

The car fills like it might even like more jetting, it took the largest ones I had in the Eddy kit.

Yet, fuel seemed good most of my pulls put 02 at 12.5 and at top point 14.1 AFR with it averaging out to be 13.1 AFR across the whole run, so perhaps a little more tweaking is in order!@

Mike

PS for the record this engine performaed with the timing set at which is 16 initial and 36 total all in at 2800 rpms.



I guessed a little more mph with your RWHP and weight, but not much, like 107. Keep tuning, and practicing your launch and you could see high 12s in good air without changing anything else.
Posted By: RobX4406

Re: Dyno pull feedback - 05/15/10 10:29 PM

Get rid of the taxi cab carb and put a 950HP Holley on it. I bet it would make 20+ more HP and more TQ throughout the range as well.

Please no "that's too big!"
Posted By: 1badx

Re: Dyno pull feedback - 05/15/10 11:04 PM

Quote:

Quote:

Quote:

Thanks Mike for the perspective. My buddy Nate ran the set up and he has bee doing it for year so I think it was a good set up, my only question is weight, what if the car weighs a little bit more then the 3860 lbs listed?

Mike



The dyno doesn't care how much the car weighs , weight only comes into play for dragstrip calculations.

Considering the heads were run out of the box I guess that's not a bad HP number .



the one time i went on a chassis dyno the operator had to enter the vehicle weight maybe some are different



Actually the weight does matter. On our Mustang dyno the more weight you add the more the dyno loads (or applies braking force) the car during a pull. Now if the question is how much will it affect your horsepower I'm not sure, it may not affect it at all or it may put the car in a load range it may never see. It doesn't look like the weight difference was substantial so I wouldn't loose sleep over it. We have doubled a cars weight to experiment with quicker boost rise and the total horsepower with correction factor did not vary that much.
Posted By: MikeyT

Re: Dyno pull feedback - 05/16/10 03:31 PM

Thanks everybody for input. I certainly appreciate it. Now, I want to look at tweaking things a bit.

Mike

PS no Rob, I'm not putting a 950 DB on my 440! I like my taxicab carburator!
Posted By: JohnRR

Re: Dyno pull feedback - 05/16/10 08:16 PM

Quote:

Quote:

Quote:

Thanks Mike for the perspective. My buddy Nate ran the set up and he has bee doing it for year so I think it was a good set up, my only question is weight, what if the car weighs a little bit more then the 3860 lbs listed?

Mike



The dyno doesn't care how much the car weighs , weight only comes into play for dragstrip calculations.

Considering the heads were run out of the box I guess that's not a bad HP number .



the one time i went on a chassis dyno the operator had to enter the vehicle weight maybe some are different



can't remember being asked that and I've been on superflow and a mustang ...
Posted By: JohnRR

Re: Dyno pull feedback - 05/16/10 08:19 PM

Quote:

Quote:

Quote:

Quote:

Thanks Mike for the perspective. My buddy Nate ran the set up and he has bee doing it for year so I think it was a good set up, my only question is weight, what if the car weighs a little bit more then the 3860 lbs listed?

Mike



The dyno doesn't care how much the car weighs , weight only comes into play for dragstrip calculations.

Considering the heads were run out of the box I guess that's not a bad HP number .



the one time i went on a chassis dyno the operator had to enter the vehicle weight maybe some are different



Actually the weight does matter. On our Mustang dyno the more weight you add the more the dyno loads (or applies braking force) the car during a pull. Now if the question is how much will it affect your horsepower I'm not sure, it may not affect it at all or it may put the car in a load range it may never see. It doesn't look like the weight difference was substantial so I wouldn't loose sleep over it. We have doubled a cars weight to experiment with quicker boost rise and the total horsepower with correction factor did not vary that much.



I did a dyno shootout in CT on a superflow, i think , and there was a guy with a dually that took off his outer rims to see if he could get a higher number because he was upset thata the big name shop that his truck was the test mule for was bested by some low life ... me ...

Maybe the dyno operator didn't know what he was doing ?
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