View Full Version : WTF happened


wicked383lt1
03-20-2011, 12:08 PM
Before I installed my LTs and ory with the ls6 intake and tune I had 300rwhp. I put all this shit on and gained 8rwhp and lost two of tq. WTF happened?

omarrakeen
03-20-2011, 12:11 PM
what about the rest of the curve? dont only compare max hp and tq any pics of before and after curves? but still strange tho!

CRAZZ28
03-20-2011, 12:12 PM
what catback do you have and was the tune done by a reputable tuner?

Rare96LT1Formula
03-20-2011, 12:14 PM
what catback do you have and was the tune done by a reputable tuner?

^ This.

Those numbers sound fairly low to begin with.

wicked383lt1
03-20-2011, 12:19 PM
I don't have a cat back and had my car dynoed by Dan from masport.

CRAZZ28
03-20-2011, 12:34 PM
I don't have a cat back and had my car dynoed by Dan from masport.

I would make a catback your next mod as the stock muffler and I pipe are now restricting your exhaust flow. You shouldn't have lost torque at all. peak tq will move a little higher in the rpm range but there is no way it should have lost any. Was it dynoed at masport both times? and was it dyno tuned or are you still on stock tune?

wicked383lt1
03-20-2011, 12:43 PM
Dynoed and tuned at masport...the first time I dynoed the car for a baseline it was a local shop in Miami. Only mods were the free mods and the car made 300rwhp and 320rwtq. I didnt think that I pipe and muffler would restrict it that much. Also my ory is vibrating on the undercarriage. But the tuner say that wouldn't affect the knock sensor

CRAZZ28
03-20-2011, 12:49 PM
Dynoed and tuned at masport...the first time I dynoed the car for a baseline it was a local shop in Miami. Only mods were the free mods and the car made 300rwhp and 320rwtq. I didnt think that I pipe and muffler would restrict it that much. Also my ory is vibrating on the undercarriage. But the tuner say that wouldn't affect the knock sensor

That is probably where you "lost" the tq then. Different dynos will ready differently. dyno jet will show more hp and tq than a mustang dyno. and even if 2 different dynos are the same model they will not read 100% the same. thats why you cant put too much though or effort into dyno numbers. If you can spare the money for a dyno pull or 2 go back to the local shop it was dynoed at for the baseline and run it again and see what it shows.

RPM WS6
03-20-2011, 02:22 PM
That is probably where you "lost" the tq then. Different dynos will ready differently. dyno jet will show more hp and tq than a mustang dyno. and even if 2 different dynos are the same model they will not read 100% the same. thats why you cant put too much though or effort into dyno numbers. If you can spare the money for a dyno pull or 2 go back to the local shop it was dynoed at for the baseline and run it again and see what it shows.

Exactly.

You can't do a direct comparison of before and after mods on two different dynos. If you go back to the original dyno, you might find that you gained more like ~20rwhp.

I also agree that the stock muffler is holding you back though. You will never see the most out of your headers and intake with a stock muffler. At the very least, get a cutout.

wicked383lt1
03-20-2011, 08:43 PM
Exactly.

You can't do a direct comparison of before and after mods on two different dynos. If you go back to the original dyno, you might find that you gained more like ~20rwhp.

I also agree that the stock muffler is holding you back though. You will never see the most out of your headers and intake with a stock muffler. At the very least, get a cutout.

Well the first one was a regular dyno not sure of the name but it was different to the 2nd one. The 2nd one was a mustang dyno. What are the differences in the two?

FNSlow
03-20-2011, 09:37 PM
haha, every dyno will read different, even 2 mustang dynos. Also, you only gain power if you remove your lowest restriction.

MikeWS6
03-20-2011, 09:49 PM
Mustang dynos read very low. A car that dynos 300rwh on a MD could put down 320-325rwh on a dyno jet.

Scoobysnacks
03-21-2011, 10:20 AM
All dynos are different and a catback or cutouts will improve a little. What matters...did your cars performance feel like it improved? Sometimes its not all about the numbers you put down especially with basic bolt ons.

WSsick
03-21-2011, 10:53 AM
OP, don't worry too much since you did it on 2 different dynos. If you are too concerned with it, then go back to a local dynojet.

^ This.

Those numbers sound fairly low to begin with.

How is 300rwhp weak to begin with? That's right on par with what a stock LS1 should put down. As he said: "Only mods were the free mods and the car made 300rwhp and 320rwtq." Those numbers are fine.

All dynos are different and a catback or cutouts will improve a little. What matters...did your cars performance feel like it improved? Sometimes its not all about the numbers you put down especially with basic bolt ons.

^That is what you should be worried about. I felt a definite gain from doing my headers on the buttdyno.

wicked383lt1
03-21-2011, 11:26 AM
OP, don't worry too much since you did it on 2 different dynos. If you are too concerned with it, then go back to a local dynojet.



How is 300rwhp weak to begin with? That's right on par with what a stock LS1 should put down. As he said: "Only mods were the free mods and the car made 300rwhp and 320rwtq." Those numbers are fine.



^That is what you should be worried about. I felt a definite gain from doing my headers on the buttdyno.
Butt dyno says that there is a nice gain rwhp...I guess your right.

RPM WS6
03-21-2011, 12:22 PM
How is 300rwhp weak to begin with? That's right on par with what a stock LS1 should put down. As he said: "Only mods were the free mods and the car made 300rwhp and 320rwtq." Those numbers are fine.

:nod:

300rwhp is a very good number for a stock A4 LS1. There are many A4s that only dyno 28x-29x rwhp in stock form.

BlackScreaminMachine
03-21-2011, 01:20 PM
:nod:

300rwhp is a very good number for a stock A4 LS1. There are many A4s that only dyno 28x-29x rwhp in stock form.

For reference. My 2002 w/ m6 and 10 bolt and no other mod then Free Ram Air, descreen of the MAF, and SLP LID put down 324 RWHP on a Superflow dyno which has characteristic of both Dynojet and a Mustang. They are big in the Diesel Tuning crowd.

m_liel
03-21-2011, 01:28 PM
Butt dyno says that there is a nice gain rwhp...I guess your right.

Don't just go off the butt dyno as those things can be deceiving at times. LOL Take it to the track and see if the car is faster than before. That way there's no question.

BlackScreaminMachine
03-21-2011, 03:04 PM
Don't just go off the butt dyno as those things can be deceiving at times. LOL Take it to the track and see if the car is faster than before. That way there's no question.

Another good reference. In order to actually "feel" a different the RWHP increase needs to be at least 8% or better improvement over the original #. Anything off the throttle is throttle response and should not count in that "opinion".

Using my prev example IF my Dyno'ed 305 RWHP stock which is not out of the realm of possibilities, and the 324 RWHP was the new figure, with dividing the new # over the old I get 6.2% increase and to be honest, I really did not "feel" it. The mods that I felt was gears (converter for A4 cars) due to the TQ multiplication and my cam swap.

Also to mention Header/Cat back + tune which was done after the lid felt a good gain too. I made 355 RWHP with that and that came to about 9.7%.

WSsick
03-21-2011, 03:15 PM
Another good reference. In order to actually "feel" a different the RWHP increase needs to be at least 8% or better improvement over the original #. Anything off the throttle is throttle response and should not count in that "opinion".

Using my prev example IF my Dyno'ed 305 RWHP stock which is not out of the realm of possibilities, and the 324 RWHP was the new figure, with dividing the new # over the old I get 6.2% increase and to be honest, I really did not "feel" it. The mods that I felt was gears (converter for A4 cars) due to the TQ multiplication and my cam swap.

Also to mention Header/Cat back + tune which was done after the lid felt a good gain too. I made 355 RWHP with that and that came to about 9.7%.

Curious to where you got the 8% figure from. I could definitely feel the difference from headers and gears, but I could even feel the difference from lid/LTs/true duals when I added an LS6 intake (without a tune). Definitely spun in places it never did before the swap. I could even feel the "smoothing" from the tune after I got it, but that wasn't really a power gain.

RPM WS6
03-21-2011, 04:51 PM
Another good reference. In order to actually "feel" a different the RWHP increase needs to be at least 8% or better improvement over the original #.

There are two things wrong with this, IMO.

1) Every person will be different. There is no possible way that you can make an exact statement for how much power gain is necessary for each and every human to notice. Just as some people are more sensitive towars noticing details, some will also be more sensitive in acceleration changes. There might be a general range, but not an exact minimum.

2) Even if you could make a reasonable general estimate for all people, I don't think this could be assigned a percentage value. On a 150hp engine, 8% = 12hp. On a 600hp engine, 8% = 48hp. That's a big difference. Furthermore, the weight of the vehicle in question will also affect what is "noticeable". On a very heavy vehicle (say, a 4x4 truck), 20hp isn't going to do much. But think about what 20hp will do to a motorcycle.

BlackScreaminMachine
03-21-2011, 07:25 PM
This has been the opinion of multiple dyno operators, some in biz, some no longer. If anyone wants contact info, i can provide.

People can argue "feel" all they like, and actually percentages. What I am stabbing at is there is a threshold that universally accepted and what it has to do is a over increase in power.

You need to take it in relation to what your dealing with. In a vaccume i.e. a perfect world we could probably find the exact figure but if you take a given driver and mod a car completely w/o their knowledge and see if they notice anything I am willing to wage that increase needed is some where in the 8-10% range.

Nobody needs to subscribe to my logic but no one can argue that it be a intriguing experiment if we could get enough examples together.

93SlowBird
04-04-2011, 01:23 PM
2 threads for this?

A.R. Shale Targa
04-04-2011, 09:00 PM
My ButtCheek Dyno has been recalibrated to +or- 3%:D

Tyler Z28
04-05-2011, 11:04 AM
even with my "slowmaster" exhaust i still made 340 to the wheels with ls6 TB headers and ORY pipe and a bitch'n tune.

the_merv
04-05-2011, 11:25 AM
Them damn ass dyno's..never accurate..:nono:

I see the Dyno as a good tuning tool, that's if you sit there for a while and calibrate the car on it. I wish I had access to one to tune my car.
My ButtCheek Dyno has been recalibrated to +or- 3%:D

Haha how'd you do it? :gay:

:lol: