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Discussion Starter #1
i pulled 140.2hp and 137.5tq. @5500 rpm

is it common for people to pull these cars in 4th gear? or 3rd?

he pulled my car in fourth gear.

mods: gude head kit,aem short ram,udp,race header,cam gears,exhaust, plug wires

let me know what you think.
mike
 

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on the dyno, the car needs to be ran in 4th in this case (1:1 ratio) so that torque multiplication from the tranny is not a factor.
 

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<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by 66mustang:
on the dyno, the car needs to be ran in 4th in this case (1:1 ratio) so that torque multiplication from the tranny is not a factor.<hr></blockquote>



I thought that 3rd gear was the standard. Mine was run in 3rd.

Mike- Your numbers are on the low side for your mods. I don't know what's up.
 

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<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by 66mustang:
on the dyno, the car needs to be ran in 4th in this case (1:1 ratio) so that torque multiplication from the tranny is not a factor.<hr></blockquote>

On your 66 Mustang, tha maybe true, but the Focus doesn't have a 1:1 gear in the case! Transaxles generally don't.

I have never understood why so many people pull in fourth as it brings the speed limiter in to play.

Nice numbers Mike.
 

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According to the 3 dyno places I have went to, they all pull in 4th to give a closer 1:1 ratio. That is what they said. And yeah, always hit the samn speed limiter.

So you are saying 3rd is just as good?

I will test that next time I am at the dyno.
 

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I think that you may get more HP and Tq if you had your cams tuned. Did you get cams with the head package? If not, get cams and you should be near my #'s with the FS head package. 158.2 Hp 141.2 Tq. Numbers are looking good though.
 

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Discussion Starter #7
yeah i got cams, but i dont think he tuned it to its potentail. i think i can pull more out of it. i dont think he tuned the cam gears enough.

mike
 

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I did a dyno run in 4th and then one right after it in 3rd. I got in:
4th - 140.2hp and 132.5tq
3rd - 135.9hp and 137.9tq
So if i did all my runs in 4th i would have 156hp in stead of the 151hp i got. But at the time I didn't have a chip so i had to dyno in 3rd.
If you compare what you got to my mods and what i dyno'd at, your power seems about right. I personally would get rid of the AEM short ram, and purchase a Volant, you would probably see better numbers that way. You should be happy, you have more torque than i do.
I have yet to hit the dyno since i got rid of my AEM CAI and added a Volant, MAferburner,and C-F-M chip. Goodluck
........Russell
 

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Discussion Starter #10
yeah i want to get rid of the short ram, and get something else. all the short ram does is suck hot air

next i want to get the throttle body and mass air

mike
 

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Discussion Starter #11
hey russell, i dont have any way to send it to you. i dont have a scanner or anything. didnt want you to think i was dissing.

mike
 

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Discussion Starter #12
air fuel wasnt hooked up. so i dont know but i know im going back when i get some new parts. so i will try to hook the a/f up then.

mike
 

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4th gear will make more power then third as there is more time to load up the engine. My car makes something like 10-15whp more in fourth then it does in third.

If you dont have a chip I would do your tuning (say cam gears or whatever) in third as the speed limiter will not come into play. The exact power numbers are not important as you just want repeatable results to obtain the best number.

At the end do a bragging rights run in fourth.
 

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The trick is to have the gearbox set in the gear that will make the power run through as few gearsets as possible!

On older style gearboxes you would just clutch the output shaft to the input shaft in 4th!

But when you were in 1st,2nd, or 3rd you would then go into the box, over a gearset to the 2nd axle in the box, and then you would go back again to the output shaft.

Depending on the quality of the gears, the lubrication etc. gears have a mechanical efficiency of some 97-99%.

Say that you go through 2 sets, you get 0.98*0.98=0.96 =96% efficiency or 4% loss. Pull that through the final drive you get 0.98*0.98*0.98=0 .94 = 94% efficiency.

Pretty basic stuff, when you find out how it works.

So if the gears are good, reduce the friction between them as much as possible......
Problem is that syncros still need some friction to work properly AFAIK..........
 

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I dyno'd in 4th cause i had a chip the first time i went. the latest time i dyno'd in 3rd cause i didn't wanna hit the speed governor while spraying my nitrous.
Personally, If you have a chip i say use 4th, if not, go with 3rd.
 

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No problem. Do you have a chip? I would REALLY recommend a chip. If you car dyno'd anything like how my car did, you might be able to take advantage of reving a tad higher.
 

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Discussion Starter #17
they burned me a chip off the dyno. its an Autotek chip but my peak power drops after 5500 and i dont understand that. thats were the cams should work the best. any help?

mike
 

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Probably just the way they tuned the cams. Was this done with a wide band O2? if so what does the A/F curve look like when you hit peak power and after it?
 
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