75mm Plenum/Throttle Body installed

[Thomas91169]

finished up installing them in about a hour. gave me quite a bit of trouble, mainly the egr or whatever dohickey is on the far right(drivers) side of the plenum. it doesnt like to be moved do a different position, and the stock bolts were too deep for the aftermarket plenum, so i had to use a couple washers.

other than that, it went pretty smooth.

i have a few side effects.
1. Gas Pedal is very stiff
2. RPM's hang at 1200rpm for a second before dropping down to 800 after revving.

the throttle cable isnt too loose nor tight, i even played around with the throttle assembly bracket that mounts to the plenum and adjusted it a few times, no difference. i believe the throttle body is just sticky and needs to wear in. WD40 had no effect on it either. though i have gotten used to a stiffer pedal.

but man, both of these mods livened up the car quite a bit. throttle response around the 1.5-3k range is very strong and crisp. exhaust tone changed a little, more throaty. top end is sadly the same though, gutless after 5500. but the power i gained in the midrange was well worth the price of the mods.

tomorrow ill fill her up with some 91 pisswater and install the diablo predator tune and play around with that.

[Thomas91169]

whoops forgot to throw up some pics

[MonteCitan]

I had shorty headers and a diablosport tune on my '02 GT... reallllly livened up the top end.. went from running 14.6@94 to 14's flat at just under 100 MPH (99.98) Only other mod I'd done was a short throw shifter (that's a must if you haven't done that one yet)

[SpectorV]

you have no reason to take that car above 5500 rpms lol it peaks at 5250, tq at 4000

can you move the throttle blade by hand with out issue, same as stock, or is that the definate problem (im sure it probably is)

[Thomas91169]

well, i noticed that when i had both TB's out, the mac unit was a little tougher to move compared to the stocker.

but after driving the car, im definately used to the stronger pedal now. now the only issue is why the rpms hang at 1200 for a second after revving(or driving) then fall back down to idle(800ish).

btw i installed the diablo today. definately gained some power, especially up top.

next on the power mods will be 4.1's, but that wont be till prolly spring.

[whipster24]

now tack a blower on there and have fun

[SpectorV]

and break stuff!

[Thomas91169]

nope, no bewst for this car. i want the stang to be very reliable, comfortable and nice, but still have a little more power than stock. no power adders(though im thinking about nitrous, cause its not on all the time, only when i need it).

after i have everything done to the stang, ill be saving up for a 1g awd shell, so i can drop a 2.3 built stroker and 60 trim into with a built shep tranny.

[Bane-]

doesnt the the newer ones all use the hyperpathetic pistons? if so...good luck with boost, they are gonna die. But nice progress on the car so far, im hoping to have my machine work done here shortly on my new block.

[MonteCitan]

Quote: Originally Posted by Bane- doesnt the the newer ones all use the hyperpathetic pistons?

and IMO I think that's what went on whipsters' car... no one replied to my post.. but his plug looked like it was more than just blown out.. it was also bent in and abused..

[Thomas91169]

Quote: Originally Posted by Bane- doesnt the the newer ones all use the hyperpathetic pistons? if so...good luck with boost, they are gonna die.

i think so. another reason to stray away from a power adder.

i kinda fixed the sticky throttle, i adjusted the screw/nut that stops the throttle closed at a certain point. its farther out now, so it stops the throttle past the sticky point. i extended it about 2 screw threads/rotations and tightened it.

though its still hanging rpms. alot of people are saying(stangnet/corral) that its just what happens with tb/plenum combos, or MAC products in particular.

[Bane-]

Quote: Originally Posted by MonteCitan and IMO I think that's what went on whipsters' car... no one replied to my post.. but his plug looked like it was more than just blown out.. it was also bent in and abused..

hmm never seen that post lol, I think thats what happened to the block I bought..machine work was going to be done to it regardless so it didnt matter if it was blown or not. one of the pistons was actually missing a piece haha

[whipster24]

the plug blowout had nothing to do with the pistons

I didn't properly torque the plugs when I swapped the autolite 103's in there and it worked itself lose before shooting out. The plug was all bent up cuz I had to drive home after it happened and the plug sat there in the hole bouncing all over the place.

The new edge engines handle boost just fine as long as you don't go crazy and get a good tune. There are plenty of engines out there putting down 450 hp to the wheels and running fine but they have great tunes. keep it around 400 rwhp with a good tune and chances are it will be fine. Reving the engine too high will hurt it more then boost will.

[whipster24]

Quote: Originally Posted by EclipseGSTdude nope, no bewst for this car. i want the stang to be very reliable, comfortable and nice, but still have a little more power than stock. no power adders(though im thinking about nitrous, cause its not on all the time, only when i need it).

Boost is only on when you get onto the gas hard

otherwise the bypass valve recirculates it all to the front of the blower.

[Thomas91169]

yeah, i know that. just like the gst i could drive around all day at in -10 vacuum. but i just dont want to force feed this car. i dont want to lose its reliablity. hell if i were to blow a plug out like you did, id be ****ed. i dont even want to think about taking the heads off to fix them, god theres so much **** on top of the 4six. the only time i want to play with the heads is maybe installing some nice cams. but even then, its like **** that, i could have a 12-13 second modded 1g awd for the price of most of the cheapest SC kits.

remember, i sold the gst cause i hated fwd. i bought the stang cause i missed rwd and that badass 4.6 roar, and i didnt get a 1g awd cause i would never buy a 1g for daily driving.

[whipster24]

I'm repairing the heads on the engine, just have to rotate the crank to the right position.

[douGT]

Quote: Originally Posted by EclipseGSTdude finished up installing them in about a hour. gave me quite a bit of trouble, mainly the egr or whatever dohickey is on the far right(drivers) side of the plenum. it doesnt like to be moved do a different position, and the stock bolts were too deep for the aftermarket plenum, so i had to use a couple washers. other than that, it went pretty smooth. i have a few side effects. 1. Gas Pedal is very stiff 2. RPM's hang at 1200rpm for a second before dropping down to 800 after revving. the throttle cable isnt too loose nor tight, i even played around with the throttle assembly bracket that mounts to the plenum and adjusted it a few times, no difference. i believe the throttle body is just sticky and needs to wear in. WD40 had no effect on it either. though i have gotten used to a stiffer pedal. but man, both of these mods livened up the car quite a bit. throttle response around the 1.5-3k range is very strong and crisp. exhaust tone changed a little, more throaty. top end is sadly the same though, gutless after 5500. but the power i gained in the midrange was well worth the price of the mods. tomorrow ill fill her up with some 91 pisswater and install the diablo predator tune and play around with that.

yep, when i installed mine, the egr valve was a b*tch. on the new plenum, the stock bolt and that stud or w/e it is wouldn't go in, my friend snapped the bolt head off of one bolt, ya i was pretty pissed. so got that out and went to a reinmans and got two new bolts for it. when i started it up, my did exactly like waht your said, sat around 1200-1300 rpms for a little bit and would drop back down to idle finally. it gets better after about a week or two, as it has for my car. but i disconnected my battery one day, and it idle the same way as the day i installed it, so i don't know what that was about, but its close to normal. the only thing different is when i rev it or in between shifts, the rpms either sit where they're at or go up 100 or so extra. but otherwise, i could tell a pretty good difference with that.

[Thomas91169]

i finally got so pissed at the dam annoyance of a throttle body it is, i slapped the stocker back on. didnt feel like it made the car any slower either. oh well, i might sell the mac TB and opt for a better piece, i hear the Accufabs or Dragon ones are alot better built than the MAC ones, and dont have these problems.