Where to start with bolt-ons...
 

I had posted this on another forum that was having a flood of "I want more HP for cheap?" posts--thought I'd post it here as well.

================================================== =====

A very common post on nearly all automotive and powersports related forums is "How can I add HP to my [fill in the blank] without spending a lot of money?".

The real answer to this question is "You can't.", however with the New-Edge Mustang GT it is possible to spend your money wisely and wake up a stock engine incrementally, without devastating your bank account.

So FWIW here are my complete best-bang-for-the-buck "bolt-on¹" recommendations for livening up a dead stock New-Edge GT (excluding active power adders)--in this order:

1. Open up the exhaust;
   
   2-1/2" from the manifolds back, H- or X-pipe as you prefer (the H-pipe will favour the lower end at the expense of HP above 5300 rpm or so). "Soundwise" think H-pipe = Musclecar, X-pipe = NASCAR. Some say that H-pipes sound better with chambered mufflers, and X-pipes best with straight-through mufflers--I am one of those.
   
   Catted or non-catted ("off-road") take your pick, it doesn't matter. There is no power advantage to the o/r pipe as compared to one with so-called "high-flow" cats; just more noise, stink from the tail-pipe and potential emissions testing problems if you live someplace that does that sort of thing.
   
   
2. Tune/Tuner;
   
   The stock tune sucks. The ignition timing is quite uninspiring and it runs very rich in open loop mode (high loads and WOT)--pig-rich on the late-'02 through '04 MY engines with the pink 21 lb/h injectors.
   
   I have never tuned even a dead stock New-Edge where the owner did not come back from their first ride with a big grin. The tuner will also let you correct the speedometer when you get to mod #3. Run a tune optimised for the highest octane fuel available in your area. The increased cost will only be $3.00 to $5.00 per tankful so just have one or two fewer beers and/or lattes in between fill-ups and enjoy the added power.
   
   
3. Final drive gears;
   
   I will not get into what ratio as that is for you to decide, though I will say that for daily drivers I recommend 3.73s. Here is a link to my How fast can I Go in Each Gear? calculator that can provide some useful numbers to help you decided.
   
   
4. TB/upper plenum;
   
   The stock upper plenum is the weak link in the intake tract, this appears in dyno charts where you can see engine output drop off sharply after 5500 rpm--installing an aftermarket plenum and TB will let the engine pull strongly right up to the rev-limiter.
   
   Any aftermarket plenum, with the stock 65 mm TB, will outflow the stock plenum with any size TB--here are Accufab's flow bench numbers, annotated by your truly, that show this. There is no need for a TB larger then 70 mm, which is optimal, however larger units will not have significant negative effect.
   
   
5. Fuel injectors;
   
   If you have the orange 19 lb/h injectors upgrading to the pink 21 lb/h units is worth the cost and effort. The 19 lb injectors are running near 90% duty cycle at the stock 260 fwHP output (flywheel HP). Ford realised this and changed to the 21 lb injectors in the late 2002, 2003 and 2004 MY production. Unfortunately they did not change the tune, which is why those models run pig-rich at WOT.
   
   The 21 lb/h injectors run just under 80% duty cycle at the stock 260 fwHP.
   
   At the top end of what can be expected from bolt-ons you may wish to consider 24 lb/h injectors as they will be operating at 80% duty cycle at 305 fwHP, or 260 rwHP--which is about the limit for the modest bolt-on modifications presented here. Operating at 80% duty cycle means they will be consistent and well-controlled, and provides reasonable headroom.
   

There is no power gain worth the $$ to be had with any aftermarket CAI. The stock intake is a CAI and a very good one to boot. The same holds true for drop-in air filters. I made 262/305 rwHP/lbft with the modest bolt-ons listed here, a finely honed tune, UDPs and the stock intake with a Purolator paper filter--that's all you need.

Other mods such as underdrive pulleys, lightweight wheels (all else being equal 18" wheels/tires weigh more than 17"), flywheels and driveshafts can improve acceleration by reducing parasitic load and rotating mass. However if you are the sort that never "floors it" and always shifts at 3k rpm then don't bother; you will never know they are installed. Their benefit is only realised under hard acceleration and mostly in the lower gears. I consistently hit the rev-limiter in 1st if not paying close attention.

Weight reduction will always improve performance, even if you are sort referred to above. Note that adding a super boombox audio system is NOT weight reduction.

That's it, just about everything else you can bolt-on¹ is cosmetic, things that if they make you happy are great, but don't expect any WOW in-your-face performance gains.

This is all my opinion so comments are welcome, however I do not care to argue about any of it or be told I am wrong--it really is my opinion...

-----------------------------------------------------
¹ - Technically superchargers/turbos and NOS are "bolt-ons" in that one does not have to disassemble the engine to add them. But for the purposes of this discussion I have excluded them.

Good post Cliffyk, how do you feel about trickflow plenums and tb's? I've talked to a few people and they swear up and down that trickflow is the best way to go, but I've heard a lot of good things about accufab. What is your opinion?

The Accufab plenum is very pretty, and in their tests outflowed the others by a small amount--an amount that is irrelevant because all the aftermarker plenums they tested provided far more air than a 4.6 L n/a engine could ever need--that with a 70 mm TB.

FWIW, the Trick Flow and Professional Products TBs and plenums are identical:

TrickFlow plenum:
http://www.paladinmicro.com/images/TFPlenumBW.jpg

Pro Products plenum:
http://www.paladinmicro.com/images/PRoProdBW.jpg

Before someone asks about the rough finish interior, in fact it improves air fow by creating a turbulent boundary layer that allows the main flow to separate from the surface and move more freely. This is way golf balls are dimpled, and why ping-pong balls seem the behave oddly--slowing down faster than is seems they should. Mirror polished surface create a lot of drag because it take higher velocities for a boundary layer to develop.

Moral: Porting is good, polishing isn't worth the effort--more about automotive aerodynamics here.

I have the PP versions:
http://www.paladinmicro.com/images/P...0Plenum720.jpg

Great post!

Thanks Cliffyk that helps a lot with my decision

That is the path I'm following, if summit would get their act together would be a plus and get me my mid pipe.

#1 is out for me as CA doesn't allow the use of aftermarket non approved cats, or mid pipe. I think only Magnaflow and Ford offer the only C.A.R.B approved versions. Gears and a tuner is next on the list for me as I already have the C&L plenum and accufab tb on the car with the stock airbox. I did drop in a amsoil Ea paper filter for the ease of cleaning and I don't like oiled cotton filters.

Nice post cliff

Hey did you get your Plenum powder coated? Is so, how much did it run you? Looks good and I'm glad to hear you like the professional products combo... I can't see the accufab setup being worth double the price.

It cost me two six-packs of Bud longnecks and is not actually the color I would have chosen, though once done I did like it.

I took it to a local custom bike shop to get it coated and my friend that ran the shop said that if I could prep it and mask it in 10 minutes he would shoot it candy apple red along with a tank and fenders he had in the booth. A couple hours and a more than a few longnecks later, I was on my way home...

Great Write Up !!! Cliffy:icon_headbang:
Great Info as always

Should be a sticky, EVERY WHERE.

What u recommend for me as far as throttle body/intake for my setup. I think improvement here would put me @ limit for my internals (425ish+ rwhp).

With stock internals I would not push it that hard and instead keep it down around 400 rwHP. Even that will negatively affect engine life--if you actually use it regularly. I once asked a close friend, who was an engineer for a couple of the "big name" tuner manufacturers for nearly 20 years, before starting his own company, "What is the practical limit for stock PI internals?". With absolutely no hesitation he said "425 HP, you can set your watch by it."

The sintered metal connecting rods are the weak link. But look at it this way, when Ford built the 2003 and 2004 390 fwHP (331 rwHP) Cobra's they changed to a forged rotating assembly--this was not just so they could spend more money, it was because they felt the 2V internals were not up top the task.

As to your TB and plenum needs, any 75 mm TB and aftermarket plenum will pass enough air for the needs of any build with a stock bottom end. Oddly, and somewhat counter-intuitively, the TB and plenum become less of a factor with forced induction. This is because as soon as the boost comes up the intake tract becomes just a large pressure vessel shoving air into the engine--the engine is no longer trying to suck in pulses of air as with running n/a, where intake size and tuning (on both sides of the TB) are prime factors.

A whole different ball game. It's sort of like connecting a 10-foot 3/4" ID hose with no nozzle to a domestic sillcock and measuring the water flow rate. And then switching to a 10-foot 1" OD hose (78% larger). The flow rate will not change by 78%, if at all, because the 3/4" hose was as big as was needed.

On an n/a setup the intake air pulses can stack up, bang into one another and create standing wave harmonics that can actually "suck out" power at certain frequencies (engine rpms). The n/a intake, especially before the TB, is not "just a pipe" as many like to put forth...

Im starting to scare myself. I actually understood that.

Thanks for making me laugh out loud. ;)

Thanks for the great post, Cliffy! Now I have a great roadmap for my 01.

Excellent write-up as usual! Thanks Cliffy!!

Go with everything listed in the 1st thread on here. I would suggest a good set of underdrive pulleys, they will free up some good power and youll feel a bit more pull in 5th gear, and better fuel millage.

Re: underdrive pulleys, from the "1st post":

"Other mods such as underdrive pulleys, lightweight wheels (all else being equal 18" wheels/tires weigh more than 17"), flywheels and driveshafts can improve acceleration by reducing parasitic load and rotating mass. However if you are the sort that never "floors it" and always shifts at 3k rpm then don't bother; you will never know they are installed. Their benefit is only realised under hard acceleration and mostly in the lower gears." [emphasis added]

Cliffyk, so if my mustang was made in april of 2002 do i have the 19 lb or 21 lb. I am assuming that it is the 19 lb.

Are they orange or pink (lavender)?

http://www.paladinmicro.com/images/F...ctor_Guide.jpg

just went and checked. 19 lbs :(. o well. thanks

They show up on eBay from time to time--here's a clean looking set for $50 plus shipping...

thanks man

mine are red what do i have?

Nice write-up. Most people would have gone straight to the CAI and then proceeded from there.

The OEM air intake after 2001 are just was good as (and sometimes better) than the aftermarket. Like with the Crown Vics, Grand Marquis, and Town Cars, the set to get was the 2004 Marauder intake. That is, until Ford stopped making them. The 2004 intakes work almost as well. We are talking FLOW RATES to the TB. Just add a good air filter, and go.

Great information! Having just recently purchased a used 2004 Mustang GT this is exactly the kind of info I need. Thanks! :)

Great thread Cliffyk.

I noticed you tune with a deltaforce tuner. Unfortunately I do not have one of those, but I do have a diablosport predator tuner. Should I just plunk on the canned 91 tune from it for now? Would that be safe with my orange top 19lb injectors? I have a 2000 GT 5-speed.

One of those preset tunes they put in the handhelds will do wonders to any vehicle,if the tune is for your vehicle. Don't expect it to feel like you have a new engine under the hood. The stock tune from Ford is setup to get you around as cheaply as possible. A custom tune (like the presets) will awaken the engine, although most do require a higher grade of fuel.

Some handheld will let you make adjustments as you add to your engine; CAI, bigger injectors, underdrive pulleys.

NOTE: Not all manufacturers use that color code for fuel injectors. I have #42 that came w/ my ProCharger kit and there isnt a bit of green on any of them. just sayin.

Clyffyk, I didnt quite get the injector part. If i would want to switch from orange 19lb to Pink 21lb or even Cobra 24lb, will i need a tune or not ? If yes, will a diablosport preset tunes will do the job ?

You do not absolutely have to retune to switch from the 19s to the 21a (Ford didn't when they made the change), however the engine will run quite rich at higher loads and WOT with the 21s and that will cost some power.

With the 24 lb/h injectors you will definitely have to retune. I have no idea whether a DiabloSport handheld supports this--I suspect not...

U will need a custom tune.

Ford designs the injectors to work at about 90% of their duty cycle. With a Naturally Aspired engine (NA), by changing one step up on injectors (19# to 21 #) the injectors do not work so hard to keep the fuel flowing. A tune will help to increase the efficiency of the injectors over the factory tune.

Do not forget that the factory tune is a compromise between power and emissions. An aftermarket tune will liven up the engine with a minor increase in timing and have the injectors working more efficient within their duty cycle.

When you start adding power adders (SC or turbo), you will need lots more fuel. That is when you get to go have your vehicle dyno-tuned for maximum horsepower (which is the mistake most people make). Power adders need lots more fuel to make their power, so it is not unusual to see a SC engine running 82Lb injectors.:icon_viking:

If you are looking for a little more hp, sure change your injectors up one step and put a tune on the engine. You will like the results.

I asked because it was kinda unclearn to me in the original post, now its makes sense, i knew it, just wasn't sure on this duty cycle thingy. I had a turboed car, but its was different than a mustang. I was doing all tuning my self because the ECU let me do that. Fuel trims, Combined trims at closed and open loops, fuel graphs and many more, but i guess with ford its all much simplier, just go to a dyno, pay 500$ and tune it :)

Or buy a tuning system that lets you do that, SCT Advantage or Delta Force's Commando will let you do all that and more--with the Moates Quarterhorse you can do it on the fly while driving (someone else is) the car...

Like Cliffyk said, buy a handheld that allows you to do all those things. Go check them out and contact the manufacturer to see to what point you can make the adjustments.

Most people are just happy enough with the pre-loaded tunes, while others will go to a dyno setup and get a custom tune. It all depends on what you want.:icon_download:

Handheld should be enough for me cause i am not gonna go crazy with my set up, maybe later on when ill have funds :) for now preloaded tune should do the job :)

throw some basic suspension mods up on here and let the power be put to the pavement. Power is nothing without traction...

You are right. If the suspension is too tight and unforgiving (like most), you never get the power down to the pavement. What good is a 650 rwhp engine if all you do is spin the tires? You need an active (for drag racing anyway in particular) suspension that allows weight transfer from the front to the rear. The vehicle will actually lift the front tires slightly as the weight goes back.

Www.allfords.com and forums.corral.net/forums both have excellent write-ups on how some people set up their own suspension.:icon_omg:

That's fantastic...


----------------------------------------
My mother told the story of three elderly women sitting in rockers at a nursing home. They were talking about their lives and the first stated she had been raised in a proper family, gone to the finest boarding schools, married a prominent doctor and lived a life of ease. The second woman said "Oh how wonderful!", the third said "That's fantastic!"

The second woman then said that she was the daughter of a tycoon, went to the finest schools in Europe, married a count and never wanted for anything. The first woman said "Oh you were so blessed!", the third woman said "That's fantastic!"

The first two turned to the third and asked about her life. She said that she lived with her grandmother after her father was killed and her mother ran off, that they were dirt poor and she only went as far as sixth grade in public school--and that her grandmother taught her to say "Fantastic!" instead of "bullshìt"...