I have 05 5at coupe. How much power do you think this car is making stock? i have heard around the 230 hp mark at the wheels.... Im a little annoyed by that being that the car weighs a lot. Its no wonder it feels so damn slow!

How much HP/TQ gains do you you think ill get if I add HI FLO cats, 5/16th plenum spacer and transgo shift kit, Z tube (stock air box) and do an uprev tune?

Budget is a little tight, but im going to tackle the transgo kit first. Then the spacer and then the Hi FLo cats and lastly the ztube and uprev tune.

Do you think ill be able to feel a drastic difference behind the wheel with just these mods together??

 

If you get dyno tuned at a shop that knows G's maybe otherwise gains are all meh.

 

Won't be much but you'll feel the difference

 

FWIW, I have a 6MT and I've added all the bolt ons (except HFC's) and a tune and have achieved 276whp and 260tq on a dynapack. And for reference, the numbers before the tune were 265Hp, and 252tq.

 

Got dang DeepDriver! Did you add any headers or do anything thing to the exhaust? Or just breather mods?

Im glad i will atleast be able to feel the difference. Thanks for letting me know what your car was making before the mods.

 

^ Exhaust, Stillen Intake, 5/16 Spacer, MREV2 Lower Plenum, Tune.

 

Damn dude even with the mrev2?! Gah lee. I wont benefit from it but thats really surprising your gains to be what they are even with this "god like" bolt on its been made out to be.
Now the throttle response is much more immediate than it was before right?
Im hoping the transgo kit will take care of the lag but i also hope the breather mods will help that as well

 

^ throttle response picked up after the tune...Yah transgo will help you out nicely.

 

Don't get too excited, Dynapack Dynos are not standard here in the US and always read about 10% higher than DynoJet (the standard here in the US) and about 22-24% higher than a Mustang dyno (common in the US but not the standard).

On a DnyoJet, he'd be at around 238 HP/226 TQ stock, and about 248 HP/234 TQ after his mods and tune.... so about +10 HP and +8 TQ after all the mods.

FYI.... most people say that High Flow Cats are one of the best mods to do on these cars for actually producing power without spending huge amounts of money.

Basically G35's don't really make much extra power from most mods. FI is the best way to go for big power gains but the stock internals of this motor aren't built to reliably handle huge boosted power in the 450+ HP range.

 

just to save you $$
And in case you don't already know,
You won't need the mrev2 with your nonrevup

 

I have a 2004 MT
Fast intentions HFC, fast intentions exhaust and 5/16 spacer ... Was 250hp at wheels
Did a tune... Maxed out at 270 at wheels

 

lol cool.
i said MREV2

 

+10 HP and +8 TQ are the maximum power increases, those mods however will boost the HP and TQ numbers much more in the lower RPM range compared to stock.
For example, at 2500 RPM the car may be pushing 118 HP, but with those mods the new number may be 138 HP+ at same RPM. An easily felt increase.

Dyno's are important, but I would wager Butt-Dyno's are more important for how fun the car feels.

 

Another question hopefully someone can answer as i couldbt get a straight answer by googling.

Are hi flo cats legal in houston TX? And will i pass inspection after the swap for emissions? I helieve the website for the cats i was looking at only said odb2 pass.

 

Gary C. said..

If your state is restrictive for emissions, then it's an at your own risk kind of deal. In California, there is a $1G fine per violation, and with two cat's? Thats $2G's.

In Nevada, unless I **** off the smog tech, I am sure I could pass with test pipes. They are no where near as thorough as you would believe in testing.

Hit a local Jiffy Lube or Quick BS Shop for your smog, they don't get paid enough to care if you have exhaust modifications. If you pass the sniffer/ODB test, you pass.

EDIT:
Kinetix HFC's
These 'claim' to be 49 state legal, but without a CARB sticker/number, it's all up in the air. Also, apparently a lot of people on here dislike Kinetix, I personally have nothing against nor for them.