sharkred7

I just purchased my first Mustang, it is a 2000 gt vert. The only mods done to it are CAI and loudmouth II catless X pipe. I am using this as my daily driver for the summer. After talking with Torrie from unleashed he figures I can gain about 20 hp with a custom tune.

I am also wanting to put on a new TB and plenum. I like the BBK TBplenem one piece for its simplicity but all I can find are the 78mm and from what I am finding in my research is that is overkill and even may hurt HP with out any FI mods.

The increases Ive seen advertised for the TBs are 7 to 12 hp. So if that is all true I can add about 30 HP or a better than 10% increase in power and maybe some increased MPGs for around $400.

My main question is should I just put on 78mm TB or find a 70 or 75mm? Also what are the disadvantages of the 78mm, if any?

Thanks from a first timer!

Z28KLR

People with that single piece BBK seem to be happy with it. Upgrading there is a worthwhile mod. I personally would go with something else just because I think that thing is a little ugly and I don't like BBK all that much, but aside from my personal opinion people who have that thing tend to be cool with it. FWIW, I have the Pro Poducts 75mm tb/plenum, been very happy with it.

The advertised gains in tuning.... You do get +20something hp, sort of. We tend to think of these sort of things in terms of "peak" gains, toward the top of the rpm range. So, if your car was rated at 260hp before a certain mod, and that mod promised 20 more then now you could say your car has 280.

I'm sure there are others, but the way tuners are advertised is a little deceptive. Peak gains will be more like around 10. You will see gains of 20 - 30 hp most definitely, but they occur more in the middle of the rpm range, say between 3000-4500. Go on AmericanMuscle.com and watch one of their videos that shows them doing a dyno run with a car after being tuned, pause it when they throw up the dyno chart and you'll see what mean.

It's a very good mod and well worth it, and honestly the advertised gains come in where you spend most of your time driving, it's just a little bit of advertising trickery is all.

school boy

Z28 nailed it, from the tb/plenum to the tune, great information. I have used the BBKtb/plenum combo and it only comes in 78mm. SR does make a 70mm
http://www.americanmuscle.com/sr-70m...ed-9604gt.html
Z28 is right, BBK's piece is ugly but works fine with no ill effects other than the cai has to be stretched to go on. As for performance, the 70mm, 75mm and 78mm will be about the same, which is not a lot. The biggest choke point is the plenum exit and it cannot be changed because of the lower intake manifold. So pick one your wallet can afford wheather it be the one piece design, two piece and whatever size.

sharkred7

Thanks for the input. I have found a 75mm professional products powerflow. It looks much better than the BBK. Thoughts? Also I am glad to hear that most of the power gains will be in that 3-4k rpm range as that is where I like to feel it. I'm not much of a WOT guy on a motor with 90K on it, especially using it as a DD.

Also I've used Torrie to tune my F150 ecos and his gains there are phenomenal and every thing he claimed and then some. Plus his customer service is above and beyond.

I know tuning a turbo ecoboost is way different than a NA 4.6 and gains without spending a lot of cash will be minimal.

Thanks for the advice

oxfordgt

A bigger TB is a waste of money. The stock TB flows more air than the heads can and flow more than enough to fill 4.6L in 2 cycles.

Get a custom tune and gears and you will be much happier and your money won't be wasted. From the factory your car is tuned very rich 12.0:1 (.816lambda) at WOT and your engine wants about 12.8:1 (.870) for best power. Also at idle a/f is set to 14.3 (.972 lambda)instead of stoich (wasting gas). But it's stoich is set to 14.69 (1.0 lambda) for gasoline but that is not what your running since pump gas is E10 with a stoich of 14.1. So if you get just a tuner and if the stoich in the tune isn't changed to 14.1 you will be running pretty lean once they set your base fuel for best power for gas 12.8+.59=13.39 A/F! I found this out once I put a wideband in to tune my car with SCT PRP and checked the BAMA tune I had. Very lean! Which is why I say get a custom tune.

Drastang

unless your getting a eddy manifold just stay stock it truly is great, the only down side is that the manifold is plastic and easily breakable I have gone through 2 and next time will most-def get a edlebrock set up with and adapter plate for stock TB to fit it. I hear that works amazing till you go boosted =)

oxfordgt

If you're gonna use that "restrictor" plate to put a stock or aftermarket plenum on a eddy intake you might as well just stay with the stock one or one of those aluminum copies of the stock one.

Drastang

oxfordgt really? and that's not a question

the stock manifold will snap it always dose yes it's the best non boosted HP you can get
but why dose that matter if you replace it every 3-4 years.

the PI metal intakes that look just like stock but are metal ALL cause a HP loss in non boosted motors do to ****ty production lines and constriction.

then you got the trickflow manifold great manifold just need cobra TB but again you will lose HP on non boosted motors due heat.

FINALY the eddy has direct ports from TB to motor. is all metal will not break just going down road when you hit a pothole. and is the only manifold that wont lower your HP over stock PI. boosted buy the 90mm intake non boosted buy adapter that WILL NOT restrict you as long as you are smart enough when installing to notice any overhang and if there is, that is all easily correctable with a sander bit n drill.

makes me horny just thinking about how better it is.

oxfordgt

I have used the trickflow intake while NA with a stock TB and it ran great. No need for a cobra TB.

The aluminum professional products and hardballer intakes suck quality wise but they make power higher in the rpm range than the stock heads and cams can which is why people report a loss in power.

Same with the eddy intake, it's operating range is much higher than stock heads and cams and do. With proper heads and cams the eddy intake is the best one but if you put a stock style TB/plenum on it it is worthless because you take the opening of the intake which is meant for a 4150 down to the size of the plenum opening. Completely chocking it off. If you're going to get that intake get a 6061 plenum. Also the eddy intake has very little plenum area and a stock style plenum does not add enough to keep the lower rpm power. The 6061 is still too small of plenum volume but much better giving you some power back in the lower rpms.

I'm running and eddy with a 6061 and 75mm TB.

Drastang

if your NA and not heavily modified you want the restriction the TB provides in the eddy, as well no need to replace maf or have a tune.

OP like oxfordgt said I'd spend money on rear gears no HP but WOW the difference. and do the TB only after you do a cam upgrade and even then still go full edelbrock