Ford Mustang Forums banner
Cancel
Create thread New Garage Forums

Shorty vs. Longtube header (dyno results)

Jump to Latest
1 - 14 of 14 Posts
B

bitemark46

· Registered
Joined
·
2,372 Posts
Discussion starter · #1 ·
Sorry I F.U.B.A.R.'d the other post trying to post the graphs. I got it now. As I said in the other post, the only difference is the headers. Both runs were on a inground dynojet. I would have dynoed them at the same place but the first shop went out of business. I'm sure once I adjust the a/f to equal the shorty header pull the LT's will have more power. -Mark

Shorties....


http://www.netsnapshot.com/users/3991/images/PK32esCoBQIAAClkYRc_3991_6.jpg


Longtubes....


http://www.tamparacing.com/phpBB2/download.php?id=6877
 
#5 ·
WOW! Someone getting similar results w/ shorties compared to longtubes?!?!?! I always here "your shorties don't give you any HP, it was a waste." I had my shorties installed in '97 before LT's became so popular. Anyway, I don't have the time or $ right now to switch, but this actually makes me feel a bit better now. Plus all the oil loss issues I've seen on this site kind of turned me off to the LT's as well......................
 
#6 ·
Wow that is pretty surprising. It looks like the same curves. The only difference I see is that your a/f for the LTs were a little richer (12.5-12.8) while the shorties were around (13.0-13.3).

How many miles in between these pulls? And I wonder what you would have pulled at the original shop. Never know how much of a difference two seperate dynos are off of each other.

Based on the information here, the shorties would be a very good choice compared to the LT's on your car, but the variables aren't the same.

John
 
Save
Reply Quote Like Like
Discussion starter · #7 ·
Ya I was surprised too. I know that once I get the a/f to 13.1-13.5 that would be atleast 5rwhp or so. So I'm guessing that with the LT's I'll have around 306rwhp and 292rwtq. As far as the length of time since the dynos is about a year. Ya I know I wish I would have dyno'd them at the same place. But I did notice that the shorties peak power is higher. The LT's starts to fall around 6k whereas the shorties is at 6200. Now it's the opposite with the torque curve. -Mark
 
#10 ·
bitemark46 said:


Shorties- Shorty style headers(Ford Motorsport)

LT's- Longtube headers(BBK)

I was posting the difference I got between the two. -Mark
Click to expand...
FMS shorties? Did you see ANY gain from stock manifolds to the shorties?

Heres's the reason I ask... I almost every dyno I've seen, FMS Shorties aren't worth but a HP or two. Yet, I've seen a lot of dynos where LT's are worth 10+ (as are the JBA shorties).

This leads me to... Either....

1) Your FMS Shorties where worth the same as BBK LT's. 10+rwhp.
2) BBK LT's are worth literally nothing. Just like the FMS Shorties.
3) The dyno tests conducted do not accurately reflect/account for all information...

:confused:
 
Save
Reply Quote Like Like
#11 ·
Many things can happen over the course of a year with the tune of the car. It's typical also that different dyno shops will give very different numbers. What is your seat of the pants impression? Anything that can be felt is at leat 10 HP.
 
Save
Reply Quote Like Like
Discussion starter · #12 ·
tmhutch said:
Many things can happen over the course of a year with the tune of the car. It's typical also that different dyno shops will give very different numbers. What is your seat of the pants impression? Anything that can be felt is at leat 10 HP.
Click to expand...
I can definately feel the difference especially between 2500 to 4000. But I'll see once the a/f is the same and I'll make a run down the track to see my mph difference. -Mark
 
#13 ·
yup...

tmhutch said:
Many things can happen over the course of a year with the tune of the car. It's typical also that different dyno shops will give very different numbers. What is your seat of the pants impression? Anything that can be felt is at leat 10 HP.
Click to expand...
It is hard to compare dyno runs from different days and even worse ....different dyno's

I am not trying to trash your thread but because of 2 different shops being used the data shown is not accurate unless you can verify dyno to dyno consistency. I have guys come in that have tuned with "Joe Blow" dyno and tell me how much power they have before we start and show the sheet. Hmmmm thats okay but the first pull on our roller is our baseline, not the previous sheet. Then we can show accurate improvement from there.

I am not saying that you did or did not pick up power but it sure would have been better data from the same dyno within a short period of time between the 2 pulls.
Shawn
 
Discussion starter · #14 ·
Re: yup...

onerichrunner said:


It is hard to compare dyno runs from different days and even worse ....different dyno's

I am not trying to trash your thread but because of 2 different shops being used the data shown is not accurate unless you can verify dyno to dyno consistency. I have guys come in that have tuned with "Joe Blow" dyno and tell me how much power they have before we start and show the sheet. Hmmmm thats okay but the first pull on our roller is our baseline, not the previous sheet. Then we can show accurate improvement from there.

I am not saying that you did or did not pick up power but it sure would have been better data from the same dyno within a short period of time between the 2 pulls.
Shawn
Click to expand...
Ya I know it would have given me a close comparison. But after the first header install I debated to do a second one. :barf:
But I'll post my mph #'s once I get the a/f right. -Mark
 
1 - 14 of 14 Posts
About this Discussion
13 Replies
7 Participants
Last post:
bitemark46
Ford Mustang Forums
posts
9.8M
members
208K
Since
2001
A forum community dedicated to Ford Mustang owners and enthusiasts. Come join the discussion about performance, production numbers, VIN decoders, modifications, troubleshooting, power adders, DIY tutorials, and more!
Full Forum Listing
Explore Our Forums
5.0/5.8 Engine Tech General Mustang Tech Windsor Engine Parts GT & SOHC Engine Tech 94/95-Specific Windsor Engine Tech