dyno shows 463hp with only cai and exhaust

Hi guys. I took my stock 04 vert for some base line dyno runs. I have used this dyno shop for many years on some of my other cars. We were all blown away with two runs that ranged from 462hp to 463hp. Other than installing a K&N CAI and a Ford racing exhaust #5230-M58 this car is stock.

I read on this board that the K&N could lean out WOT AFR so I had a bung welded in the Stock exhaust about 6 inches from the exhaust manifold and checked the AFR with my LM-1 Before the CAI install several years ago. I was in the high 11.8-12.0 AFR range totally stock. After installing the CAI the AFR was in the 12.3-12.4 range. I never checked AFR after I put on the Ford racing exhaust. ( guess I should have)

When we did these pulls with both mods the AFR at the TAIL PIPE pipe was consistently over 13 mostly in the 13.2 range....... S****, f*** so we stopped. I wasn't worried about AFR with these mods so I didn't bother to weld in a bung and we just used a tail pipe sensor.

I read on this board that safe AFR is around 12. So, am I getting these HP numbers cause I am way lean? Is a tail pipe sensor really a good guide? It seems to me that they usually are lean after the cats.

I want to make sure I am getting correct AFR # so I am going to weld in a bung for the dyno sensor (Horriba?) and re check.
I am amazed that these mods could change AFR that much on the stock tune, but I would sure like your comments. these HP numbers are too good to be true and I bet its because of an extremely lean condition.

Thank you all for any ideas you have..............bob

You might have a pulley? I have only seen 440rwhp Cobras with no pulleys, if not, amazing Cobra you got there.

I bought the car new from a Ford dealership with 34 miles on it so I don't think its got a pulley. Really I am blown away by the numbers and if its not a lean afr situation causing it all I can assume is its the combination of the fr500 exhaust and the CAI. I hope so but i bet we will end up having to reduce wot afr and lose a bunch of power. On the other hand, I got a 7 year ford warrantee, so if it goes, well, I'm in a pretty good position for warrantee (but not fool proof).

anybody else on the AFR issue and these numbers? thanks.........bob

AFR is off or dyno is off. I've seen 420hp with those mods, but that's it. You would need a tune and a pulley to get 460rwp. Are those supposedly SAE numbers?

Maybe its the cousin to this Mach 1

http://cgi.ebay.com/ebaymotors/Ford...018QQitemZ280225387841QQrdZ1QQsspagenameZWDVW

It's got 390hp!!!

mine with a 2.81 upper jlt cai and off road x pipe made 438 with a very agressive tune.He needs to have the dyno checked and re calibrated.My numbers were on a dynojet 248 with winpep7.Possibly if he has a dyno dynamics and he has altered the settings you would see those numbers.

Something is not right.

Is this a Dyno Jet? In the Denver area? At what altitude?

Measure both pulley diameters, lower and upper.
If stock, then the altitude compensation in an SAE number or something related to the dyno set up/calibration may be f'ed up.:shrug:

Or maybe it's a MAGIC cold air and cat back.:bored:

well, it seemed too good to be true so I appreciate the comments. I would have been happy with 410hp. Maybe you guys are right and the dyno is off . I had my SCT with me and was going to load a custom tune, but we left it alone after seeing those numbers. Unless ford or the dealer put different pulleys on this car, they are stock. That would be a trip if they did. Stranger things have happened and I will check.

I am going to spend the dough and try a different dyno and operator just to see. I know the numbers will vary some but if its even close to this, then I guess its MAGIC!



Any comments about the AFR?? Is it out of the question to get these numbers because its so lean?

Thanks again for your help, sill hoping to get some ideas on the AFRr issue.

rsilver said:

well, it seemed too good to be true so I appreciate the comments. I would have been happy with 410hp. Maybe you guys are right and the dyno is off . I had my SCT with me and was going to load a custom tune, but we left it alone after seeing those numbers. Unless ford or the dealer put different pulleys on this car, they are stock. That would be a trip if they did. Stranger things have happened and I will check.

I am going to spend the dough and try a different dyno and operator just to see. I know the numbers will vary some but if its even close to this, then I guess its MAGIC!



Any comments about the AFR?? Is it out of the question to get these numbers because its so lean?

Thanks again for your help, sill hoping to get some ideas on the AFRr issue.

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after the cats, from what i've read, will show +.5 or more leaner A/F.

What brand of dyno?

It's one thing to make 440 with those mods but even more unlikely at that altitude, something is way off. It's been asked already but are the numbers uncorrected (actual) by any chance?

As far as your A/F contributing, yes running lean could make a bit higher numbers but not that much and I'm pretty sure once you go leaner than mid-high 12s you actually start losing hp. Mid to high elevens are considered safe and make nice power.

I know the numbers are adjusted for denver's altitude to represent what would be achieved at sea level ( forgive my terminology) and therefor not what was actually achieved at this altitude. So, its a theoretical sea level number.
He has two dynos and I think this one was the MD800 but I know it was an MD, not sure which one. Will talk to him tomorrow and get more specifics on altitude adjustment errors, which dyno, software etc. BTW torque was 408lbs if that proves or disproves anything.

thanks for the comments one and all ......I really appreciate everyones thoughts.

u need to take a a/f reading before the cats.weld in a bung.your a/f if its totally stock will be safe in the 11.8 to 12.0 range.If you pulley it i would say 11.5 to 11.7 or so.Keeping timing under 20 degrees.

if they had to put in the weight of the car, find out what the number was for the weight that he put in. If he went too high on that then that would give you the inflated numbers as well, as the car would show spinning just as fast but with heavier weight

This is the only reason why I am not a MD dyno fan. An operator can make it look like you are making just about any number they want you to with the flick of a key-stroke. Most run them correctly, but a few screw things up and give everyone a bad name.

-Jeff

This is the only reason why I am not a MD dyno fan. An operator can make it look like you are making just about any number they want you to with the flick of a key-stroke. Most run them correctly, but a few screw things up and give everyone a bad name.

-Jeff

Ok, I am a fool and didn't know enough or ask the right questions when I had this done. No excuse for being a dumb f*** so my apologies for wasting everyones time. But I post this so that others may not make the same mistakes and just go in blind and ask for a base line run on a dyno.

The correction factor is f***** up. These are not SAE numbers but some other number called SCP which I could not get a definition of but the operator used instead of SAE . He told me its 10% to 15% higher than SAE and in effect is just a larger correction factor.
Thats great huh? Its OK for doing comparasons for mods But It is of no use as to an absolute number or as a standard. So, I really don't know where I am when comparing to what is posted, i assume around 400 hp SAE. I thought everyone did SAE on dynos! Wrong.

I also gave him the wrong weight for the car (a spiraling cascade of errors)
and used 3550# instead of 3780# which I believe is correct for an 04 vert.

The dyno is a mustang 1750.

gonna head to another dyno, I guess dyno jet and get base line and then see what happens when we load in cold air program from amazon. Will post then
but I don't expect any MAGIC!!!

Thanks to all, you guys saved me from thinking I had a 463 hp CAI/cat back cobra!!! Again my apologies, but I learned a lot........thanks bob

rsilver said:

Ok, I am a fool and didn't know enough or ask the right questions when I had this done. No excuse for being a dumb f*** so my apologies for wasting everyones time. But I post this so that others may not make the same mistakes and just go in blind and ask for a base line run on a dyno.

The correction factor is f***** up. These are not SAE numbers but some other number called SCP which I could not get a definition of but the operator used instead of SAE . He told me its 10% to 15% higher than SAE and in effect is just a larger correction factor.
Thats great huh? Its OK for doing comparasons for mods But It is of no use as to an absolute number or as a standard. So, I really don't know where I am when comparing to what is posted, i assume around 400 hp SAE. I thought everyone did SAE on dynos! Wrong.

I also gave him the wrong weight for the car (a spiraling cascade of errors)
and used 3550# instead of 3780# which I believe is correct for an 04 vert.

The dyno is a mustang 1750.

gonna head to another dyno, I guess dyno jet and get base line and then see what happens when we load in cold air program from amazon. Will post then
but I don't expect any MAGIC!!!

Thanks to all, you guys saved me from thinking I had a 463 hp CAI/cat back cobra!!! Again my apologies, but I learned a lot........thanks bob

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It's really OK man. You are not wasting our time, and this is something that happens more often than you would think, as far as inaccurate dyno readings go. That is why we are here. Most of us just throw general facts out, and it appears that we are annoyed or whatever, but most often this is not the case, we are all most likely just repeating what has been told to us time and time again, so it just becomes robotic after a while. Keep us posted on your findings.

-Jeff

rsilver said:

Again my apologies, but I learned a lot........thanks bob

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Again don't sweat it man there are many people who have had pulls done with different corrections. It's not totally your fault, they should have asked what numbers you wanted. The SAE CF is usually considered the standard but there will always be different CFs used because they yield higher numbers. And again different dynos will give different numbers even with the same CF, not to mention sea level corrections and atmosphereric conditions, so we can never really get completely objective hp numbers to compare unless we all use the same dyno at the same time. There are just certain hp ranges that we know given mods will produce.

Bob.. I hope that you got the answers that you needed from Rick yesterday..
the experience that you had is a prime example why a dyno should be viewed as a tool to get an optimal tune on your vehicle...the data used from each dyno run is essential for the tuner to dial the tune in...did you discuss letting Rick do a remote tuning session for you? I'm not sure if you and I talked any about that but he can dial your tune in from here in SC while you are on the dyno in your location...you just have to set it up with me..