General LSX Automobile Discussion - Dissapointing dyno numbers.




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90TSiAWD
02-16-2010, 09:59 AM
Okay so I got my car dyno'ed today and I'm kind of dissapointed to say the least.

My mods are Pacesetter LT's, ORY, TSP Rumbler CB, SLP Lid with K&N which was pretty dirty, 3400 stall, and 3.42s. Untuned. It was also knock retarding according to his EFI live the stock computer was pulling about 3 degrees out.

It was on a mustang dyno converter locked my best numbers were 303HP 303TQ.

I was pretty dissapointed because my 00 WS6 M6 dynoed 312/324 stock, but that was on a dyno jet.

so the guy showed my a graph on the computer from a 04 GTO bone stock it dynoed 270/270 so it made me feel a little better.

What do you guys think?


Wesmanw02
02-16-2010, 10:03 AM
The automatic with the 3200 stall will steal a lot of power. Most of the high stall auto guys don't worry about dyno numbers for this reason, they just go to the track and see what it will do. Thats more accurate as to its actual performance.

Clean your air filter and find out why you were getting knock retard. Even 3 degrees of timing can really kill your numbers.

Also, how do you have 3.42's in an auto car?? You swap them in??

90TSiAWD
02-16-2010, 10:06 AM
Yes I swapped the 3.42s in and as for the air filter a bunch of us just went to watch my buddy get his car dyno'ed so I wasn't planning on doing it when we got there more people wanted to do it so they talked me into it because they would get a discount.

Also tried to spray it but he had his EFI live hooked to it and it hit 7 degrees of KR so we aborted that run.


rcastillo002
02-16-2010, 10:17 AM
stalled auto cars dont really make sense on the dyno lol

Xtreme864
02-16-2010, 10:21 AM
I wouldn't worry about dyno numbers bro, focus more on ET. If anything else, you'll just suprise people that you can probably run close to mid 12's on 300whp

araber89
02-16-2010, 12:01 PM
Ya check out my sig for dyno numbers with basically more bolt ons. This was through an M6 so that should show you how much your trans is taking up.

JScamaro
02-16-2010, 02:04 PM
I'd be more worried as to why the PCM is pulling the timing. Just for comparison, my car put down 320 rwhp with my aftermarket torque converter when it had full bolt on and stock cam.

Juicy J
02-16-2010, 02:14 PM
They are a little bit low, but not that low. Are you throwing any codes that might help you to figure out why it's pulling timing? If your filter is pretty dirty, I would put money down that your MAF is dirty. You could probably pick up a few HP by doing a tune up if you haven't in a while.. Regardless, dyno numbers don't matter.

usafcrewchief01
02-16-2010, 02:18 PM
I have damn close to the same mods as you minus the catback exhaust and I put in a 3500 stall converter and my numbers were 317hp and 329 ft/lbs.. Dyno numbers for an auto car are always disappointing for the most part. M6's have the high numbers so just know that the number you have is going to the ground and be happy about it. My dad still tells me that my car is stupid fast for so close to stock. I believe he is right about our cars.

slayerized6
02-16-2010, 02:36 PM
your numbers seem about right. mustang dynos tend to read lower than most other dynos. get an ls6 intake and go on a dynojet and youll see some good numbers

RPM WS6
02-16-2010, 02:54 PM
Those numbers seem about right for a mustang dyno, those mods, and 806 heads/LS1 intake.

You might be ~10rwhp down or so, but that's likely due to the KR. Fix that, and you'll probably hit 310+rwhp on the same dyno....more on a dynojet.

90TSiAWD
02-16-2010, 06:20 PM
The tuner said it could be getting the KR from the exhaust hitting or something but idk about that cuz we hit the spray for a couple seconds and the KR went all the way to 7 degrees.

SOMbitch
02-16-2010, 07:00 PM
The knock sensor on 98's are known to be finicky. It is why I replaced mine along with the harnesses when my heads went on. Not seeing the car this is just a guess but I wanted to throw it out there.....

PowerShift408
02-16-2010, 07:13 PM
I'd say your numbers are close for being on a Mustang dyno. Figure out that knock and getting running right and you'll pick up a few ponies.

Wesmanw02
02-16-2010, 09:23 PM
The tuner said it could be getting the KR from the exhaust hitting or something but idk about that cuz we hit the spray for a couple seconds and the KR went all the way to 7 degrees.

What kind of fuel were you running??

The fact that the knock increased when you sprayed may indicate that it was actual knock instead of false knock.

GT-OH
02-16-2010, 09:26 PM
Numbers seem about right. I would get it tuned and take it to the track :D

90TSiAWD
02-16-2010, 10:33 PM
What kind of fuel were you running??

The fact that the knock increased when you sprayed may indicate that it was actual knock instead of false knock.

That's what I thought well I put 91 octane from 76 in it.

Numbers seem about right. I would get it tuned and take it to the track :D

+1 gotta put my LS6 intake on first.

Wesmanw02
02-16-2010, 10:53 PM
That's what I thought well I put 91 octane from 76 in it.

Get some 93 in there. It should eliminate your K/R.

RPM WS6
02-16-2010, 11:26 PM
That's what I thought well I put 91 octane from 76 in it.

An engine life spent living on CA-grade 91 octane under unknown driving conditions from previous owners means that you might have a lot of carbon build up in the combustion chambers and/or fouled injector tips.

I'd spend some time on a major tune-up before digging any deeper. Seafoam via a vacuum line for the top end cleaning, Red Line and/or Seafoam treatment in the fuel (for the injectors & top end), new fuel filter, new plugs, clean/replace air filter, and do a good cleaning on the MAF. Do all that, and you should be rid of any actual detonation.

Dskeet6
02-17-2010, 10:02 AM
7 degrees???? not good.....

elky489
02-17-2010, 10:24 AM
what year is your car,this plays a big part along with the big stall.If its a ls1 intake and 853 headed auto car your numbers are about dead on,i have a customer who has long tubes,lid,12 bolt 3.73s 3600 tci converter and makes 312 on a dyno jet unlocked,but his car goes mid 12s with ease...Dynos are not everything my friend,its just a number,and the auto cars show poor numbers on the dyno.But big deal.

elky489
02-17-2010, 10:25 AM
Ya ok just saw your sig,you have a 98,worst pcm,worst heads .your numbers are ok.

Wesmanw02
02-17-2010, 10:48 AM
Ya ok just saw your sig,you have a 98,worst pcm,worst heads .your numbers are ok.

Plenty of '98 guys dyno the same as 99+ guys. The difference in the heads is negligeable, and 98's have a slightly larger cam as well. So basically it ends up evening out. My 98 put down 341WHP with bolt ons and a tune, same as 99+ cars.

RPM WS6
02-17-2010, 11:56 AM
Ya ok just saw your sig,you have a 98,worst pcm,worst heads .your numbers are ok.

The PCM isn't holding him back (on a stock tune vs a stock '99+ PCM and tune). '98 PCM is harder to tune for big power setups, like forced induction, but even still a good tuner can do fine with it. Either way, he's got a stock tune so this has nothing to do with it.

It's the LS1 intake and 806 heads holding the car back a bit, in addition to the KR.

TImmy_Jones
02-17-2010, 12:29 PM
Sorry for the newbness....why would a big stall show low #s? Loose converter isnt putting all the power down?


I cant believe I don't know this, since I had a 3400 stall in my intercooled/built tranny grand prix, GTP. Stall made it easier to launch, but would still roast the tires at 45-50

90TSiAWD
02-17-2010, 12:33 PM
An engine life spent living on CA-grade 91 octane under unknown driving conditions from previous owners means that you might have a lot of carbon build up in the combustion chambers and/or fouled injector tips.

I'd spend some time on a major tune-up before digging any deeper. Seafoam via a vacuum line for the top end cleaning, Red Line and/or Seafoam treatment in the fuel (for the injectors & top end), new fuel filter, new plugs, clean/replace air filter, and do a good cleaning on the MAF. Do all that, and you should be rid of any actual detonation.

Well the car cam from oregon, some older couple owned it so for all I know they could have been running 87 Lol. I did replace the plugs but the wires is on the list before the tune, fuel filter is new and I Seafoamed it a few weeks ago.

7 degrees???? not good.....

Word.

The PCM isn't holding him back (on a stock tune vs a stock '99+ PCM and tune). '98 PCM is harder to tune for big power setups, like forced induction, but even still a good tuner can do fine with it. Either way, he's got a stock tune so this has nothing to do with it.

It's the LS1 intake and 806 heads holding the car back a bit, in addition to the KR.

I think the heads will make a very small difference but I have the LS6 intake to put on as well.

MonmouthCtyLS7
02-17-2010, 12:44 PM
Yea that is very low

BobDoLe
02-17-2010, 01:59 PM
any more details on the stall?
i also blame the 98 knock sensors - do you ever hear pinging? regardless of whether the knock is real, the timing pulled is real and is holding the car back a few.
the 7 degrees on the bottle sounds like you need to tune for it, though... might as well also desensitize (in the tune) the knock sensors while you're in there.

NoMoreLS1
02-17-2010, 02:10 PM
Why would you dyno it and not get it tuned? You spent all that money on the upgrades, but don't get the most important part done... the tune??? :confused: From what I gather from your post, you also sprayed it without a tune? :confused:

What kind of plugs and wires are you using? What is the gap set at? Are you still using the stock heat shields on an aftermarket wire such as an MSD? If you use the stock heat shield on an MSD wire, it does not allow the wire to slide down all the way on the plug. I would suggest NGK TR6s (non platinum) if you spray it. Who makes the stall that you are using?

What brand fuel are you using? Not all 91 or 93 octane gasolines are the same.

A stall converter will generally show a slightly lower hp number if not locked... not much though in your case. Torque generally falls off when unlocked, but won't "fall off" when the converter is locked... looking more like a stick car dyno.

Unless your car is making a lot of power, there is no reason to beat up the converter by locking it on the dyno. Plus... you aren't locking the converter in 3rd gear at the track, are you?

Being that you have 3.42s, that will also "show" a lower dyno number. Gear swaps are usually good for a 8-10 rwhp "loss".

90TSiAWD
02-17-2010, 02:33 PM
Why would you dyno it and not get it tuned? You spent all that money on the upgrades, but don't get the most important part done... the tune??? :confused: From what I gather from your post, you also sprayed it without a tune? :confused:

What kind of plugs and wires are you using? What is the gap set at? Are you still using the stock heat shields on an aftermarket wire such as an MSD? If you use the stock heat shield on an MSD wire, it does not allow the wire to slide down all the way on the plug. I would suggest NGK TR6s (non platinum) if you spray it. Who makes the stall that you are using?

What brand fuel are you using? Not all 91 or 93 octane gasolines are the same.

A stall converter will generally show a slightly lower hp number if not locked... not much though in your case. Torque generally falls off when unlocked, but won't "fall off" when the converter is locked... looking more like a stick car dyno.

Unless your car is making a lot of power, there is no reason to beat up the converter by locking it on the dyno. Plus... you aren't locking the converter in 3rd gear at the track, are you?

Being that you have 3.42s, that will also "show" a lower dyno number. Gear swaps are usually good for a 8-10 rwhp "loss".

I'm using TR6's but will be switching to a BR6EF non-projected. It's a Fuddle yes a Fuddle 3400.

As stated before on the thread I am getting MSD wires and the only reason I dyno'ed it is because my buddy and a bunch of us were going to the dyno and they talked me into it so we got a discount. I only spent 25 bucks on the dyno runs. Otherwise I would never have got it dyno'ed then let alone on a mustang dyno.

Also stated before I used gas from 76 but usually get it from the gas station on base.

RPM WS6
02-17-2010, 02:43 PM
Well the car cam from oregon, some older couple owned it so for all I know they could have been running 87 Lol. I did replace the plugs but the wires is on the list before the tune, fuel filter is new and I Seafoamed it a few weeks ago.

Clean the MAF, seriously. It's had a K&N filter, which means some oil and gunk has probably built up on the wires. This will cause all kinds of issues depending on how dirty the wires are.

I agree with the others that mention a little bit of false KR being the product of '98 knock sensors, but not 7 degrees. Sounds like you've done most of the tune up, but make sure that MAF is clean (I like to use Q-tips and rubbing alcohol).

90TSiAWD
02-17-2010, 03:09 PM
So with the knock sensors do I have to replace them with 99+ ones or just new 98 ones.

NoMoreLS1
02-17-2010, 04:18 PM
It's also possible that you pinched the knock sensor harness when you installed the LS6 intake manifold.

Replace the knock sensors with the '99-'02 style.

Fuddle converter? That might be part of the problem too. :)

thunderstruck507
02-17-2010, 07:45 PM
Get it tuned and try again, especially if you're getting knock

elky489
02-18-2010, 01:31 AM
Also dont use msd wires,there crap and fall apart.
And correct the ecu doesnt hold him back stock,but if the guy tuning it doesnt know how to tune the older os then it will hold him back,thats what i was trying to get at.And im sorry a 243 head on 01 and up is far better then 853 heads.I would also turn the knocks down aswell.

elky489
02-18-2010, 01:33 AM
Also like others have said,if its had a k and n filter and ever been over oiled your maff is dirty and causing issues,I just fixed a car that had that same problem,kid didnt know and put a ton of oil on it,maff went nuts and fuel trims were locked at 15%,and gave the car some very odd drivabilty issues and even caused issues at wot.

RPM WS6
02-18-2010, 02:24 AM
And im sorry a 243 head on 01 and up is far better then 853 heads.I would also turn the knocks down aswell.

The 243 is an LS6 head. No F-body ever came stock with that head.

As for 853s, '98s didn't come stock with those either, they had 806s.

'01-'02 cars came with 241s, which are in fact better flowing heads than the 806/853, however the improvement would be very slight on an otherwise stock engined '98-'00 car. The '01/'02 will usually dyno a bit higher stock due to the combination of the better heads, LS6 intake, and improved exhaust manifolds. Only thing hold the '01/'02 back is the *slightly* milder cam. A '98-'00 cam in an otherwise totally stock '01/'02 engine would be the best possibile combination of factory LS1 parts.

Zeke34
02-18-2010, 02:25 AM
Get it tuned and try again, especially if you're getting knock

+1 ... Also, who's tuning your car for you?

90TSiAWD
02-18-2010, 10:28 AM
It's also possible that you pinched the knock sensor harness when you installed the LS6 intake manifold.

Replace the knock sensors with the '99-'02 style.

Fuddle converter? That might be part of the problem too. :)


The LS6 isn't even installed yet, I stated the several times in this thread.

Do I have to replace the harness to when I replace them?

The converter is great I don't know why people rag on them but this is a converter from earlier when they were actually good so before they got shitty I guess.

406malibu
02-18-2010, 10:40 AM
Also dont use msd wires,there crap and fall apart.
And correct the ecu doesnt hold him back stock,but if the guy tuning it doesnt know how to tune the older os then it will hold him back,thats what i was trying to get at.And im sorry a 243 head on 01 and up is far better then 853 heads.I would also turn the knocks down aswell.

Couple things wrong with this. I think you meant to type 241, which if thats the case, yes they are good for about 5 hp because of the way it was cast. However they changed to 241 in mid year 2000 not 2001. If you did mean 243, of course its better than 853, the 243's were ls6/ls2 heads.

NoMoreLS1
02-18-2010, 12:10 PM
Sorry that I must have overlooked that you didn't install the LS6 intake manifold. :)

You don't have to replace the knock sensor harness as it will work with the newer style sensors. But check that the harness is in good shape before you install the LS6 intake obviously. It's possible that the intake manifold was off at one point. Torque the knock sensors properly. Make sure to use new intake manifold seals as well. Fel Pro makes a nice set for $25.

MSD wires are the best wires out there.

As far as the Fuddle... I still think it is inefficient.

RPM WS6
02-18-2010, 12:34 PM
However they changed to 241 in mid year 2000 not 2001.

Not really mid year, only some of the very late '00 cars received them.

nitr0racing21
02-18-2010, 12:42 PM
i had 340 340/ to the wheels and ran 11(stalled auto)

90TSiAWD
02-18-2010, 01:43 PM
Sorry that I must have overlooked that you didn't install the LS6 intake manifold. :)

You don't have to replace the knock sensor harness as it will work with the newer style sensors. But check that the harness is in good shape before you install the LS6 intake obviously. It's possible that the intake manifold was off at one point. Torque the knock sensors properly. Make sure to use new intake manifold seals as well. Fel Pro makes a nice set for $25.

MSD wires are the best wires out there.

As far as the Fuddle... I still think it is inefficient.

Cool I'll go ahead and do the knock sensors too when I put the LS6 on.

i had 340 340/ to the wheels and ran 11(stalled auto)

I hope to put around 340 with my tune on a dyno jet.

elky489
02-19-2010, 02:25 AM
ive seen 243s on 02s,lots of 241s on the earlier years,People these days put to much imphasis on dyno numbers,i own a dyno and i think that lol.His lower numbers can stem from alot of things,he said he isnt using the ls6 intake,that hurts numbers,early knock sensors will cause kr issues,and we all know that these cars like the timing.Type of dyno,weather conditions.So many things play a factor.Big stalled autos are power eaters aswell.

RPM WS6
02-19-2010, 10:05 AM
ive seen 243s on 02s

You may in fact have, but it wasn't stock on an F-body. Ever. Period.

jonlisa973
02-23-2010, 02:24 PM
Yeah, don't dwell too much on the numbers, mustang dynos usually show more real world numbers anyway.

owlpuff
02-24-2010, 09:26 PM
just my $.02 Stop buying gas on post, it's downright cruddy. unless you like cleaning your engine regularly from clogs, and removing all that water from your tank... Stopped buying fuel from AAFES in 2006 and never looked back..

PowerShift408
02-24-2010, 09:29 PM
just my $.02 Stop buying gas on post, it's downright cruddy. unless you like cleaning your engine regularly from clogs, and removing all that water from your tank... Stopped buying fuel from AAFES in 2006 and never looked back..

Agreed.