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Took LuLu to the Dyno today


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Yep...Took LuLu out for a custom dyno tune today and she loves the results. So do I.

 

First, we strapped her down to re-run a failed dyno test after a one-piece drive shaft install back in July. This pull revealed that a one-piece lightweight drive shaft from LFP produced 4 RWHP and 1 lb. of RWTQ. On this data alone, I can't say the drive shaft mod is a worthwhile investment. "But wait, there's more!" I'm not telling the whole story yet.

 

Next I bought a DiabloSport Predator from Corey (Simpson Performance) and he set out to work his magic on a professional tune. End result: 296.05 RWHP/311.33 RWTQ, and a very sexy flat AFR of 13.0 throughout the the pull. I would post the dyno report, but I have no resources for that.

 

It's the nature of the 4.6L-3V to fall off peak power at 6200 RPM, and it was the same case with my 4.6L-4V engines. I suppose a "square" engine can spin only so fast. Corey moved the rev limiter up to 7000 RPM, and we we went for a drive in country.

 

All I can say is "holly sh!t"! 1st, 2nd and 3rd gear pull like never before. Broke the tires loose and I went sideways in the 2-3 shift. IMHO, LuLu is now a low 13 second 1/4 mile driver. Not everything shows up on a dyno.

 

One other thing...The 2 hour drive home at 70 MPH produced 28.6 MPG. Cool...I'll take it!

 

Back to the drive shaft...Corey commented that he is beginning to believe that HP/TQ gains from a driveshaft upgrade is turning into an urban legend, and I would agree that it doesn't show much on a dyno. But, there are many popular mods that do not show their worth on a dyno, for instance, a smaller, lighter torque converter on an auto tranny. You won't see much improvement on the rollers, but it will show at tree. Plus, there are safety issues to consider, and added up, I don't feel I wasted my money investing in the drive shaft.

 

Happy motoring, gents!

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I don't see that a light driveshaft can ever "add" HP, but it can certainly make it easier for the HP your engine has to turn the rear wheels and move the car quicker. Lighter wheels do the same thing, for example. Less rotating mass.

 

Thank's for posting the dyno and tune info.

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I don't see that a light driveshaft can ever "add" HP, but it can certainly make it easier for the HP your engine has to turn the rear wheels and move the car quicker. Lighter wheels do the same thing, for example. Less rotating mass.

 

Thank's for posting the dyno and tune info.

You are welcome.

 

I won't disagree with you, sir, but I believe we are saying the same thing. You say "add", I say "recover" Either way, the more power that gets through the parasitic drive line drag is a power gain in the movement of the car. The two-pice OEM drive shaft is quite heavy, maybe 4X the aftermarket replacement. When you don't have to burn power turning that dead weight, more power meets the pavement. No matter what it's called, it's new power to the wheels.

 

I'm always cautious of marketing brags. When I see words like "as much as" and "up to", I'm looking for the fine print. While this LFP aftermarket drive shaft may not show very much in power gains on a dyno, LuLu is definately quicker. Quick enough that I have set aside my plans for 4:10 gears.

 

Looking back at your previous stock dyno numbers (276rwhp, 303rwtq), does this mean you had 280rwhp and 304rwtq with only the lightweight drive shaft; and thus a 15rwhp and 8rwtq over this with the tune?

I'm not sure how to reply to your question, but I can tell you that the numbers in my sig are right off the dyno reports. The shorty headers were installed and dyno tested before the drive shaft.

 

Bone stock: 275.55 RWHP/300.85 RWTQ

Post shorty header install: 284.54 RWHP/306.80 RWTQ

Post drive shaft install: 288.82 RWHP/307.22 RWTQ

Post custom tune: 296.05 RWHP/311.33 RWTQ

 

If you could drive LuLu, you would say these numbers are on the conservative side. She feels a lot quicker than 296/311 at the wheels.

 

Be safe, gents.

 

EDIT: BTW, I forgot to mention one other thing...The DiabloSport Predator hand held tuner had no problem saving my stock SGT/FRP tune, and I did not have to restore a stock MGT tune before programming the custom tune. Whew, that was a load off my mind.

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Ok sorry. So 7 peak rwhp gain and 4 peak rwtq gain from the dyno tune over your previous setup. Got it. In your case it looks like the shorty headers gave more of a boost than the dynotune. Hmmm.

 

Well if you ever come up against a stock C5 Vette you should do well.

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Ok sorry. So 7 peak rwhp gain and 4 peak rwtq gain from the dyno tune over your previous setup. Got it. In your case it looks like the shorty headers gave more of a boost than the dynotune. Hmmm.

 

Well if you ever come up against a stock C5 Vette you should do well.

I see your point now, AF, and I apologize for disappointing you. Please don't forget a focused and greatly improved AFR and a safe tune in your figures? Do you really know that much about it all?

 

I'm not much of a "dyno racer", too many variables in that game. For me, it's merely a test tool which guides a tuner, and a dyno test tells a fraction of the "real world" story. I've seen lower dyno numbers beat the snot out of larger numbers on the blacktop, and you have to put the car on the blacktop to know more about what your mods have accomplished. I am merely trying to provide 411 to other SGT owners considering similar mods, and in the language they want to hear it. I really don't care what LuLu's RWHP is, RWHP has little to do with moving the car forward on the pavement in a real world environment.

 

BTW...There are others here who have purchased and installed "canned" tunes, and produced less RWHP and RWTQ than LuLu produced in her "bone stock" dyno test. Maybe that was just my luck?

 

LuLu's shorty headers were an experiment in power gains for the least investment. A place to start for a budget minded SGT owner, and a peek at a new offering from Pypes. Think "what works, what doesn't"? While I earned some gains from the shortys, they were not significant gains. Neither was the drive shaft mod, but it all adds up in the end, right?

 

Had I spent the coins for a set of Kook's long tubes and Random Technology hi-flow cats, dyno numbers may have been higher. Maybe after I add a blower into the mix, I'll spend more time on re-evaluating LuLu's exhaust?

 

AF...I know how my LuLu runs and if I can locate a set of drag radials soon, very high 12s are expected the next time I get to the 1/4 mile. Until then, I am quite pleased with my overall results for the money involved. Maybe someday we'll meet up, and I'll toss you her keys. Then you can post your evaluation of how I spent my money and what I got for it.

 

We done now?

 

Excuse me, gents, while I shop for tires. Just under 10K miles, and the original BFGs are toast.

 

Pirelli's?

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I apologize for disappointing you

Who said you disappointed me? Based on what Tucker of JLT, Breenspeed, and Bamachips have all (in and what other owners have seen, your numbers confirm what others have seen. When I got my stock SGT dynoed last month an 07 SGT that had been dynotuned at that shop had 13 more pk hp and 8 more pk torque

Do you really know that much about it all?...We done now?
Not sure why you feel then need to respond in this manner. You have most dyno data with different mods on your SGT that I have run acrossed. I'm simply asking questions to get a better feel for what different mods do on our car.

 

I'll remember not to ask you any more questions. Yea I'm done now.

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LuLu, I was responding to "HP/TQ gains from a driveshaft upgrade" in your post, however, I think you and I are saying the same thing. Thanks for the reply.

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Mac:

I know what you mean. I also went with the LFP (Coast) DS and UCA. I ran a dyno test afterward. I gained rotational mass with the larger wheels/tires and lost mass with the Aluminum DS. The "after" dyno was 279.08hp with a curious down-spike at @4150rpm. I am limiting my "spirited" driving while I chase this down.

My SOTP feeling, even though I have less HP to the wheels overall, is that Betsy is faster and quicker off the line. Part of that is certainly the better skins. I think a tune is next for me also, and I will post results.

Here is the sheet from Aug 1st and the stock 4th of July... You can see the curios dips. Any suggestions?

 

080108dyno.jpg

 

stockdyno7-4-08.jpg

Dan

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I would just put a huffer on it and be done with it. Parts that cost a few hundred bucks a pop for single digit increases aren't very cost effective, other than gears. Nothing like being blown... :hide:

 

Happy motoring Sir!

 

+1

 

See my dyno results in my signature. I spent (or wasted) $1500 to get 310 rwhp pre Whipple. $5K later, I am not afraid of anyone!

 

Lulu, the driveshaft upgrade is worth it. The best seat of the pants improvement short of the SC.

 

Michael

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Here is the sheet from Aug 1st and the stock 4th of July... You can see the curios dips. Any suggestions?

Dan

Yes, Dan, I do have a suggestion. IMHO, your Air-Fuel ratio is very unstable and needs to smooth out. A 13.0-13.5 across the board is ideal, and your dyno charts show that it's all over the map. This is not uncommon and it can be fixed easy enough, but not with a stock SAI/FRP tune, or, a canned tune. You will need the services of a professional dyno tuner, and a hand held programmer to remap the AFR and fuel pump(s) duty cycle. Every car is different and you may not see improved dyno numbers after the tune, but your performance on the street will amaze you.

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Thanks Mac.

I will look into a dyno tune shop around here. I think there's a good one in Tracy, Ca. Remembered reading here somewhere... I like the feel of my power transfer after the DS installation, but was totally bummed out when I saw the "after" dyno numbers...

Dan

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It's the nature of the 4.6L-3V to fall off peak power at 6200 RPM, and it was the same case with my 4.6L-4V engines. I suppose a "square" engine can spin only so fast. Corey moved the rev limiter up to 7000 RPM, and we we went for a drive in country.

 

 

Mac - I remember you telling me that RPM's were not a big deal it was only the torque that you worried about. This was when we were talking about the Bullitt. Have you changed your mind about RPM's or did I misunderstand you?

Swede

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BTW, I forgot to mention one other thing...The DiabloSport Predator hand held tuner had no problem saving my stock SGT/FRP tune, and I did not have to restore a stock MGT tune before programming the custom tune. Whew, that was a load off my mind.

That's interesting. So I guess the canned Paxton tune that comes with the Shelby Paxton supercharger (on a DiabloSport Predator) probably has a software check to look for a stock Mustang GT tune and if it doesn't find it the program stops the read/load. I think this may be the case with other "canned" tunes.

 

Sounds like the lesson learned is, regardless of which brand of hand held tuner hardware, a good custom tuner that knows what they're doing can manipulate the software to read in the baseline load and write over it to get the most out of each car.

 

Glad the tune worked out, my experience has been similar, the custom tunes are without a doubt the best money I have spent on the car.

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Mac - You didn't answer my question on post #15. It is about you saying that RPM's did not do anything to a car ( A members post about 2008 Bullitt with a RPM redline @ 6500).

Now your loving the fact that your redline is 7000 and the words "holly shit" come to mind. I also understand that other things were done to the car but the redline is what I am refering to. I will say that if I have misquoted you please excuse my post. However you seem to post long and hard about 4.6's and I just want to know since you are a strong piece of 411 on those engines.

Swede

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It's the nature of the 4.6L-3V to fall off peak power at 6200 RPM, and it was the same case with my 4.6L-4V engines. I suppose a "square" engine can spin only so fast. Corey moved the rev limiter up to 7000 RPM, and we we went for a drive in country.

 

Mac - I remember you telling me that RPM's were not a big deal it was only the torque that you worried about. This was when we were talking about the Bullitt. Have you changed your mind about RPM's or did I misunderstand you?

Swede

By "RPMs" do you mean RWHP? If so, then yes, you have, Swede. Personally IMHO, RWTQ is more important than RWHP. I haven't changed my mind, but I am trying to deliver more 411 to others in a language that most here speak. Many are preoccupied with the Brake/RWHP numbers, I am not.

 

This time around, LuLu delivered 296 RWPH, but she also delivered 311 RWTQ, and I like that number. Moreover, IMHO it's not so important how a car performs on a dyno, but how it performs on the pavement, and that's pure torque.

 

Mac, did you raise the rev limiter to 7000 and do you feel the drive train is safe to redline at 7K? Does this allow you to raise the top speed limiter also?

I won't be driving LuLu anywhere near 7000 RPM. According to the dyno report, there is no reason go that high. The power band ( both HP and TQ combined) peaks at 6000 RPM and drops very fast after that. Very fast, and you lose power and speed quickly. So, no reason to flirt with the redline, nothing to reach for beyond 6200 RPM but a sharp loss in forward movement. I need a shift light now, the 4.6L-3V revs very quickly and I want to shift at my peak, not pass it by. I feel the drive train is safe up to 6200 RPM.

 

I believe the "rev limiter" and "top speed limiter" are the same EEC function. No where in my big red books do I find any mention of a "rev limiter" per say, however, section 1-63 of the Power Train and Electronic Controls manual describes how the EEC will shut down the engine at a predefined RPM. In street slang, I hear folks calling this "hitting the rev limiter".

 

Before we bumped the limiter up, LuLu's was set at 6000 RPM. After this change to 7000 RPM, LuLu is still making power and pulling hard at 6000 RPM. But, don't flirt with this on your own. Several systems must be tweaked to insure proper timing, spark, fuel and fuel pump performance. It's the territory of a professional tuner.

 

Wow it looks like AFBLUE's car dyno'd out almost as high bone stock as yours did with your mods. It's like you said, each car is different and then the temperature and humidity can effect the dyno numbers. I like the idea of doing things to keep dropping the weight.

I agree that comparing dynos reports can be complicated, moreso on-line. Another member here added some mods (gears and a tune?) and his dyno numbers came in just above my bone stock numbers, very close. Lots of variables to deal with, which is why I dyno test after every important mod, and compare the "difference" before and after. Some mods won't produce any difference at all on a dyno, but kick butt on the street.

 

Style of dyno is an important consideration as well. DynoJets and Mustang dynos (as test tools), deliver quite different performance numbers, and in all fairness should not be compared to each other.

 

Happy motoring, gents.

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Hmmmmm, I still believe that this 4.6 will pull strong beyond the factory redline of 6200 RPM's. My car craps @ 6200 and I feel it pulling hard at 6200. Just like you said, some mods won't show any difference on the dyno but kick butt on the streets.

So in your estimation, your satisifed with what you have now and will not SC your car? You also "believe" high 12's are in your near future with this set up? Now I can live with high 12's all day long, especially without a SC!!

Thanks Mac for your answers.

 

Swede

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Wow it looks like AFBLUE's car dyno'd out almost as high bone stock as yours did with your mods. It's like you said, each car is different and then the temperature and humidity can effect the dyno numbers. I like the idea of doing things to keep dropping the weight.

You can't compare my dyno numbers to dynojet numbers. The dyno I used was a Australian one called dyno dynamics. It reads higher than dynojet. I will eventually get a stock pull on a dynojet and I would be very surprised if it wasn't +/- 5rwhp of 277.

 

If Lulu had been on the same dynanmeter as my car she would have probably been >305rwhp and 320rwtq

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