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Went to get my dyno runs today on my stock 08SGT


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+1...Agreed. No retune is required. Moreover, most popular hand-held programmers will save your incumbent tune for restoration at a later time. Doesn't matter if it's a FMC tune, or the SAI/FRP tune, it gets saved. Change out from the SAI/FRP tune with a DiabloSport, or, SCT hand-held programmer, and you will be okay down the road.

 

Likewise...Don't expect a lot in performance from an upgraded bellows (elbow). It's a smoother flow of air which enhances throttle tip-in, but it does not produce/deliver any more power than you already have present.

 

However, it does look cool...

 

I just installed the Steeda elbow without retuning and you were RIGHT my car seems to be running fine. In the future I will ask around when something doe not seem right. I copied this note from the Steeda ad which is why I bought the tuner in the first place.

 

NOTE: Will work with FRPP intakes but will require retuning if using FRPP's tune with one of our SCT tuners. Shelby GT and GT-H cars are equipped with FRPP intakes. Will require retune with SCT tuner for these vehicles

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I just installed the Steeda elbow without retuning and you were RIGHT my car seems to be running fine. In the future I will ask around when something doe not seem right. I copied this note from the Steeda ad which is why I bought the tuner in the first place.

 

NOTE: Will work with FRPP intakes but will require retuning if using FRPP's tune with one of our SCT tuners. Shelby GT and GT-H cars are equipped with FRPP intakes. Will require retune with SCT tuner for these vehicles

 

That could just be to protect themselves since it can certainly affect AFs and therefore cat-life/emissions -- they have to stay clear of the regs and would not say that, imo, if there was not some valid reason ...even if works fine (which it should).

 

Has anyone dyno'd before, put on the Steeda elbow and then did another pull right after (with no retune) ...with A/Fs for both pulls? Would be interesting to see what/if it shows up. The elbow should flow a bit more and a bit differently since it's smooth (not corrugated) and shaped differently (affects flow concentricity/layering). As I said above: "The elbow *can* affect how the MAF sees the airflow (even tho it's upstream) but likely the tune will not have any problem with it."

 

Btw, that's the kind of thing dynos are most usefull for -- as a benchmarking measurement tool: baselining, making changes, rebaselining, retuning, rebaseling, etc... "racing the dyno" for HP/Tq braging rights is fun, but it's true value is in guaging the effect and effectiveness of various and alternative changes.

 

While a custom tune might cost $400 or more, vanilla pulls are ususally cheap ($80-100 or so, sometimes much less on "dyno-days") becasue shops know that experienced racers know that if you want to come to understand your car and it's mods/alternatives, the dyno is your long-term friend. Just some thoughts...

 

:end of :soapbox: ;-)

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  • 2 weeks later...
Retuning is NOT necessary if all you do is add an aftermarket bellows (elbow) to an SGT. The improvements in air flow are minor, and well within the parameters of the SGT/FRP flexible programming. Thus, the improved bellows is for dress only and with that said, the upgrade may be worth the cost as a visual engine bay feature. You will not have to retune, a few WOT passes on any on-ramp, or, back road will do the trick.

 

 

I swear offcer I was just calibrating my computer!.... :hysterical:

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That could just be to protect themselves since it can certainly affect AFs and therefore cat-life/emissions -- they have to stay clear of the regs and would not say that, imo, if there was not some valid reason ...even if works fine (which it should).

 

Has anyone dyno'd before, put on the Steeda elbow and then did another pull right after (with no retune) ...with A/Fs for both pulls? Would be interesting to see what/if it shows up. The elbow should flow a bit more and a bit differently since it's smooth (not corrugated) and shaped differently (affects flow concentricity/layering). As I said above: "The elbow *can* affect how the MAF sees the airflow (even tho it's upstream) but likely the tune will not have any problem with it."

There is no need to remeasure before and after AFRs, there's no change in air volume from the addition of just a smoother air path. The FRP 90mm MAF on the SGT cannot read what has already passed through, it doesn't have "eyes in the back of it's head". This is not a forced induction system, the air flow into the engine is a process of suction through the throttle body. Smooth out the air path and you get better flow, but not more air.

 

Moreover, in a WOT dyno pull, AFRs are dictated by pre-programmed AF maps in the EEC. This is what custom tuning is all about, adjusting the AF maps (as well as other features such as spark and timing) to specific plots for desired performance. What the MAF "sees" in a WOT condition has little to do with MAF readings at WOT.

 

If you want to play around with it all, get a larger MAF, TB and injectors, and a professional tune...But, I don't think this will produce pleasing results for the money involved.

 

For serious and precise tuning, I suggest y'all install an O2 bung in the exhaust pipe, and use a wide band AF meter. Driver's side down pipe, between the factory sensor and the cat. The #8 cylinder is last on the food chain for fuel, and if the AFR is rich or lean, a wide band AF meter will show you the worst case scenario. Tailpipe sniffers are okay as a guide, but are grossly inaccurate after the exhaust gasses have been processed by the exhaust system.

 

Hope this helps, happy motoring gents.

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Never said anyone needed to measure before and after -- just was wondering if anyone has since that's the only way to see what difference, if any, is produced in A/Fs, HP. Tq, etc and thereby get insight on how it handles the change. That's what dynos are for -- a tool to measure before and after changes are made to isolate results.

 

The MAF doesn't need eyes in the back of it's head. It's not a matter of reading what's already passed thru it <lol> It's a matter of what's passing thru it not being in the pattern that the MAF assumed it's reading. A MAF does not read flow from wall-to-wall and therefore assumes a specific flow-concentricity profile for the cross-section of air moving through the MAF. In fact a hot wire MAFn doesn't read flow at all, it reads the degree to which the air charge dynamically cools a special heated wire and thereby affects the return voltage to the ECU. This is a good surrogate for air mass but only to the degree the MAF is reading a cross-sectional pattern consistent with it's engineering design calibration. This "mass-air" determination is critical to the dynamic "load" calculation which affects many other aspects of engine management. Change the concentricity across the MAF and you change the reading even for the exact same flow volume, air density, air temp, etc. (an old trick [and not recommended] to fool the MAF into having more 'capacity' is to modify its orientation in the airstream, as many Termie owners found out). Change the volume plus the flow concentricity and the returned MAF voltage no longer represents what the WOT tables assumed and WOT A/Fs will be affected.

 

Even tho the elbow is downstream, cross-sectional flow diferences (concentricity) from a different nearby downstream pattern can change flow across the MAF's *actual* sensing area (concentricity flow changes). These pattern changes are due to fundamental differences in the laminar flow at various distances from the tube inner surface because corrugated tubes and smooth tubes have very differnet concentricity flow patterns and that can affect how air is pushed across the MAF. Interestingly, while corrugated tube serfaces will flow *less* for a given diamenter than smooth surfaced tubes, the *variation* in flow layering (onion rings/concentricity) across the central portion is typically, and counterintuitively, more consistent for a corrugated tube.

 

That said, small changes that are fairly consistent in pattern will likely be fine in that they will not bump the ECU into limp-home but they will still produce results that are different and not necessarily optimum even tho they may or may not produce more power as a net result.

 

Btw, an NA motor and FI motor are not all that different -- effectively just the source and degree of pressure applied: about 14.6 psi at sea-level on 30.00 baro day for NA and more than that for 'FI.' FI is just a term. NA is merely an atmospherically-forced-induction engine. An NA motor may see suction below the intake valve, but it's only carying amounts of *pressure* in the intake -- just like FI.

 

 

Yeah, the A/Fs are dictated by the tables but it's the MAF that largely determines how the tables are indexed/used to actually have the right "A" (air) calculation for the preprogrammed "F' (fuel) pulse-width modulation at the injector. Mess with anything that affects A in a way that is opaque to the ECU (whether unmetered air or inaccurately metered air, as discussed above) and the A/F will not be what the WOT tables think they are.

 

 

You probably don't need a larger MAF unless it's peggine (returning over 4.7 volts or so) to the ECU at peak WOT power. The ECU feeds the MAF 5.0 volts; if it's 100% staurated it will return 5.0 volts. You never want a pegged MAF, but you're solid up to 4.7v or so, maybe a bit more (depends).

 

 

+1 on the W/B O2 in the right place -- essential to accurate readings. Tailpipe sniffers or anything after the cats are not very usefull for precise tuning.

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I was recently at JLT Performance since it is just minutes from my house. I too wanted to dress up the FRRP elbow. He has nothing that will work with the FRRP tune. Now he said that he would be happy to sell me or anyone else with an SGT his product, however he has tested his agianst the FRRP cold air intake and even after giving it a custom tune the gain in HP was no more then 2 to 3 horses at any given time. According to the man that sells and makes the product don't waste the money. Find another way to dress up the tube.

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I was recently at JLT Performance since it is just minutes from my house. I too wanted to dress up the FRRP elbow. He has nothing that will work with the FRRP tune. Now he said that he would be happy to sell me or anyone else with an SGT his product, however he has tested his agianst the FRRP cold air intake and even after giving it a custom tune the gain in HP was no more then 2 to 3 horses at any given time. According to the man that sells and makes the product don't waste the money. Find another way to dress up the tube.

 

Jay Tucker is a straight shooter ...good feedback ...thanks.

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Opps...Looks like I woke up 68Fastback again. Sorry, Gents.

 

"Dear Doctor Dan"...Hey "Doc", thanks for the "Engineering 101" on MAFs and AFRs. You're a pretty smart man, a tip of my hat to you. But, how appropriate is such an intense and extensive lecture to our community at large?

 

I think we said the same thing, that no retuning is necessary for the SGT when adding just a smoother bellows. But, I said it a little lighter, and easier for many folks to understand and keep up.

 

I'm not posting here to go to your school and I am not participating in your extension courses. I post here to help the few owners who are not so "automotive inclined" at this time. The few who are not sure what MAF and AFR stand for. I don't like leaving people behind in the fog, and I like to keep things simple, maybe give them an unembarrassing clue as to where to look next to learn more.

 

If my posts bother you, Doc, I can stop. Seems like every time I post something slightly techincal, you follow me with your textbook lecture that prolly confuses these few SGT owner more than it guides them. I don't know...Boggles my mind.

 

I'm sure this will change once you get your own SGT and start scraping knuckles yourself, but until then, please keep in mind that many readers here have not achieved your level of knowledge and expertise and could grossly misunderstand your thoughts and suggestions. Like me, I presume my audience to be grass roots wrenches of varied degrees. SGT owners with a lot of curiosoty about the "how and why" of things SGT. I try not to talk over them, sometimes I learn from them as I investigate their questions. Soimetimes questions I never asked myself.

 

Case in point...I know all about repositioning the MAF for a premium reading, prolly did this calculation and relocation 10x more than you. I owned the first supercharged Marauder on the planet and I went through a lot of trials and tests (some with FMC watching) to keep it competitive. Car and Driver centerfold in '03...While you're reading, read up on that?

 

Your suggestion is surely a valuable tuning "trick", but it's also professional tuner territory. IMHO, leave it to the pros? I would never (and did not) suggest this "trick" to anyone. As valuable as it is in precise fine tuning, repositioning can have some very negative results when attempted by a novice. BTW, this "trick" is valuable only to super/turbo charged cars where the air charge is forced through the MAF. It has no value to N/A engines.

 

There are different ways to accomplish forced induction. Sometimes called "blow through" and other times called "suck through", this was a task for early pioneers of modular engines with power adders, and there is some tuning/adjustment to the blow-off valve of choice as well. However, today we are blessed with "kits", and these points are not important anymore. The research has been done and the decisions have been made, and I am pleased I was a part of that investigative process years ago.

 

However, this MAF "trick" will not improve naturally aspriated engines and may cause havoc in the hands of a novice. This is what professional tuners attend to, what you pay for in a professional tune and there is no replacement for a pro-dyno tune. Do not try this at home.

 

So, lighten up Doc? Find a few words easier on the ears. Your knowledge is very valuable to us all, but we have to comprehend the lingo too, get me? And, keep it SGT related, K?

 

Okay...Back to our regular programming...

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Doc? :hysterical: That's really funny, Mac. You're so adept at spin-doctoring you might have missed your true calling as a political writer :) Ok, I think it's only fair then that I hereby volunteer a moniker to you ...the Spin-doc ;)

 

 

Either you don't actually read my posts or don't quite get what I'm trying to explain on -- not sure which, and it's puzzling because you strike me as a smart guy with real experience -- certainly more hands-on experience with the modulars than I have. Still, I'd be glad to try to clarify any of my posts that don't seem to make sense. The whole idea here, imo, is the sharing.

 

I'm sorry you see that as talking down to folks -- maybe you should reread some of your own posts? I'm genuinely honored when someone takes the time to go out of their way to share with me. It says to me they care; they're interested in helping; they're willing to go out of their way for me.

 

You keep re-spinning things I say by making like we're saying the same thing in a different way -- I assure you we are not.

 

My posts are intended to benefit others' unerstanding. You appear to be of the "give a man a fish" school (i.e. here's what you should do), and I'm more of the "teach a man to fish" school (i.e. here's how it works so you can better decide what's best for you to do). I'm sure you'll find some way to re-spin that too. Please spare me.

 

I'm not threatened by freely sharing insights with others (the few good ones I actually have, anyway <lol>) and I very much appreciate when others take their valuable time to do likewise with me because I know how much effort it takes. Imho, the sharing of understanding is one of the truly wonderfull things about this site! I learn somehting new every day. I trust you do too.

 

I'm sure you've had more modern cars and done more with them than I ever have and I freely admit that I have little hand-on with the modulars (besides some typical stuff), but the laws have of physics have not changed in the intevening decades -- at least not that I'm aware.

 

So let me suggest you post whatever you want and I'll do likewise. We don't have to agree. Feel free to elaborate on the actual content of any of my posts. Diversity of opinion is good, imo. My sincerest regrets if you're not comfortable with that but I have no intention of bounding what I do/don't choose to share with others based on your assessment of what folks on this forum are/aren't capable of understanding. I'll let them decide that since maybe they're a lot smarter than you give them credit for. In fact I think such discussions foster better insight and I suspect others benefit more from such diversity of thought. I know I do.

 

One thing's for sure, collectively we are far smarter than any of us are individually -- that's my sincerest belief.

 

-Dan

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Hey Doc...While I feel complimented by your suggestion that I could be a good speech writer for any politician, that's not my role/goal in life. I am too much of a blue collar "hard hat" kind of guy to spit out that swill. I'm working class and proud of it. The only one on my block without an I-Pod. Go figure?

 

Visited a friend's patio last night, found some great comedy. Had a few beers, played some poker, and I brought a sample of your postings to see how the conversation would flow among other car guys at the table (excuse me while I light my cigar and sip on my ice cold Miller Light). I read to them this passage, and left it on the table.

 

"Even tho the elbow is downstream, cross-sectional flow diferences (concentricity) from a different nearby downstream pattern can change flow across the MAF's *actual* sensing area (concentricity flow changes). These pattern changes are due to fundamental differences in the laminar flow at various distances from the tube inner surface because corrugated tubes and smooth tubes have very differnet concentricity flow patterns and that can affect how air is pushed across the MAF. Interestingly, while corrugated tube serfaces will flow *less* for a given diamenter than smooth surfaced tubes, the *variation* in flow layering (onion rings/concentricity) across the central portion is typically, and counterintuitively, more consistent for a corrugated tube."

 

I didn't misunderstand one word of this, Doc. I got every word you posted. But, ya know what others at the table got out of it?

 

"Hey...Let's get some onion rings!"

"I got a laminar floor in my mud room!"

(over our shoulders from the wifey) "Consentricity is the focus of knots, important when quilting and knitting...Could learn to spell better...".

(from a child who snuck out of bed) "Tube! Tube, daddy! Boat!" (the reply was "maybe this weekend, Kenney, we'll see what the weather holds, now back to bed with you!)

 

I shared with them your last post here, Doc, and our grand old man of this block, Jerry, woke up from his slumber on the lounge with a start. "ACK...Who in God's name is this guy quoting Celtic tables? Give a fish, teach to fish? What does he know of it? Was he there? Did he fish for life?" Damn Americans...I have to agree, Doc. You have taken a time honored Celtic table and turned it into some kind of lesson for us SGT owners. Sad. And worthless.

 

I said to Jerry "Settle down now, Dad, it's just a few words on the Internet". He fired back "Blast you, Mac! We don't need more stupid!" As Jerry headed back to his lounge mumbling "damn black car and so noisey too, you should shut her up Mac, we don't need to hear from her!". Jerry is 96 years old...And so it goes, on my block.

 

Doc? :hysterical: That's really funny, Mac. You're so adept at spin-doctoring you might have missed your true calling as a political writer :) Ok, I think it's only fair then that I hereby volunteer a moniker to you ...the Spin-doc ;)

 

 

Either you don't actually read my posts or don't quite get what I'm trying to explain on -- not sure which, and it's puzzling because you strike me as a smart guy with real experience -- certainly more hands-on experience with the modulars than I have. Still, I'd be glad to try to clarify any of my posts that don't seem to make sense. The whole idea here, imo, is the sharing.

 

I'm sorry you see that as talking down to folks -- maybe you should reread some of your own posts? I'm genuinely honored when someone takes the time to go out of their way to share with me. It says to me they care; they're interested in helping; they're willing to go out of their way for me.

 

You keep re-spinning things I say by making like we're saying the same thing in a different way -- I assure you we are not.

 

My posts are intended to benefit others' unerstanding. You appear to be of the "give a man a fish" school (i.e. here's what you should do), and I'm more of the "teach a man to fish" school (i.e. here's how it works so you can better decide what's best for you to do). I'm sure you'll find some way to re-spin that too. Please spare me.

 

I'm not threatened by freely sharing insights with others (the few good ones I actually have, anyway <lol>) and I very much appreciate when others take their valuable time to do likewise with me because I know how much effort it takes. Imho, the sharing of understanding is one of the truly wonderfull things about this site! I learn somehting new every day. I trust you do too.

 

I'm sure you've had more modern cars and done more with them than I ever have and I freely admit that I have little hand-on with the modulars (besides some typical stuff), but the laws have of physics have not changed in the intevening decades -- at least not that I'm aware.

 

So let me suggest you post whatever you want and I'll do likewise. We don't have to agree. Feel free to elaborate on the actual content of any of my posts. Diversity of opinion is good, imo. My sincerest regrets if you're not comfortable with that but I have no intention of bounding what I do/don't choose to share with others based on your assessment of what folks on this forum are/aren't capable of understanding. I'll let them decide that since maybe they're a lot smarter than you give them credit for. In fact I think such discussions foster better insight and I suspect others benefit more from such diversity of thought. I know I do.

 

One thing's for sure, collectively we are far smarter than any of us are individually -- that's my sincerest belief.

 

-Dan

Thanks, but no thanks, Doc. I'm no spin doctor, just relaying things as they break free spontaneously in my neighborhood. I imagine it's not so different for most of us out here.

 

Yeah, I may have some time under my hood(s) but that doesn't make me right. IMHO, I'm just getting by. But, I don't think your approach is the a better approach either.

 

Talk in simple plain english, and not so "high on the hog" as Jerry later stated. Come on down to us simple folks and spell it out in simple terms. I am sure we will all learn more, and learn easier.

 

Doc...You have the focus and knowledge which earns a deserving title of "King of the technical book". But, it's not always about the book. Some of us just like to strap in and run. How we get there isn't as important to us, as long as we get there. Temper your posts with some consideration for us blue collar/hard hat street racers, and you can be our "King of the Book" too.

 

Peace y'all.

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Great thread and outstanding stock dyno numbers, AFBLUE.

 

Can somebody with an automatic transmission post their stock SGT dyno numbers? I have searched but could not find any for the automatics...

 

Should the stock auto SGTs expect around 270rwhp on the dyno? too low, too high?

 

thanks,

Erich

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Great thread and outstanding stock dyno numbers, AFBLUE.

 

Can somebody with an automatic transmission post their stock SGT dyno numbers? I have searched but could not find any for the automatics...

 

Should the stock auto SGTs expect around 270rwhp on the dyno? too low, too high?

 

thanks,

Erich

My SGT is a stick car, but I've had high performance auto trannys in the past.

 

My bone stock dyno came in at 275 RWHP and 300 RWTQ. Estimating a 12-15 percent loss of power in the drive train, this is about right.

 

I would expect a 25 percent loss with a stock auto tranny, and predicting 270 RWHP is unrealistic, considering the loss in power from the drive train and factory torque converter. More li8ke 260-265 RWHP.

 

You can address this loss with mods, such as a lighter/tighter torque converter, tranny programming and shift kit, and a one-piece drive shaft, but still, do not expect to see less than an 18 percent loss. This is the nature of the game with auto trannys.

 

Auto trannys earn their keep though. Properly set up and tuned, an auto tranny can achieve 1.6 or lower 60 foot time, and can shift faster than any human being. If you are serious about drag racing and maybe thinking about a bracket car, auto tranny could be the way to go. You can't beat them.

 

Happy motoring!

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Sir Spin-doc Mac, you've done it again. :hysterical: ...or at least you've tried.

 

So, your admittedly beer-drinking, poker-playing, half-asleep buds in the 'hood are your official sounding board for my tech posts? I'm flattered. :hysterical: Whatever works for ya -- and please pass the onion rings! ;)

 

I'm glad you're enjoying my posts. If that should change, there's always the Ignore feature.

 

Btw, concentricity *is* spelled with a "c" not an "s."

 

Peace, bro.

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I just have 1 SGT auto entry. Mark1 got 247rwhp and 256rwtq on a dynojet

 

Looks like you're in VA, so near sea-level (goodness), but high water-vapor (e.g. high relative humidity on a hot day) and low barometrics (e.g. rainy/overcast "low") could do that.

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