Safest way to get 15%-20% more NA HP and torque vs. stock

[m.wood0213]

Another for headers and tune, probably what ill end up doing as well.

[cf6mech]

E85 and tune,...then remove some weight/rotational mass....lighter rims,...carbon drive shaft.

[mrk1]

Bump up the final drive to 4.44 or 4.55. Won't give you a dyno to brag about but keeps you in the power you have more often. Should make it much easier to stay above the dip.

Price is very reasonable but not usually a drive way kinda job.

[Sonolin]

Originally Posted by mrk1

Bump up the final drive to 4.44 or 4.55. Won't give you a dyno to brag about but keeps you in the power you have more often. Should make it much easier to stay above the dip.

Price is very reasonable but not usually a drive way kinda job.

I'm interested in this as well but I'm curious about highway rpms... I wouldn't want my rpms to be higher than ~3500 in 6th going 70-80.

I don't think 4.44 would be too bad.

If only I had more gears, lol.

[7thgear]

Originally Posted by Sonolin

I wouldn't want my rpms to be higher than ~3500 in 6th going 70-80.

why?

[mrk1]

I strongly believe a new final drive will give the car the bump most NA people want but in my experience its a hard sell. No shiny bits to show off.

The 4.44 should be a very good upgrade for a street car that sees a lot of highway. My personal M3 has been changed from a 3.68 to 3.91 and that made a wonderful difference with out making highway unbearable. Now comparing the ratios is a bit apples to oranges but you can look at the numerical increase, my example is a pretty small increase yet a noticeable gain. If you dont see much highway or dont care about the extra gas burnt, go for the 4.55. The highest I've seen 4.67 is probably best only for a track car.

[Opposed]

Originally Posted by mrk1

I strongly believe a new final drive will give the car the bump most NA people want but in my experience its a hard sell. No shiny bits to show off.

The 4.44 should be a very good upgrade for a street car that sees a lot of highway. My personal M3 has been changed from a 3.68 to 3.91 and that made a wonderful difference with out making highway unbearable. Now comparing the ratios is a bit apples to oranges but you can look at the numerical increase, my example is a pretty small increase yet a noticeable gain. If you dont see much highway or dont care about the extra gas burnt, go for the 4.55. The highest I've seen 4.67 is probably best only for a track car.

May not be shiny, but its a great sleeper mod.

[Sonolin]

Originally Posted by 7thgear

why?

I'm planning to go with headers + full exhaust. I hate drone, and going past 80 in stock form it starts getting annoying for longer drives. I wouldn't want to be sitting at 4k rpm in 6th crusing with a full exhaust & header

Also: MPGs

[7thgear]

Originally Posted by Sonolin

I'm planning to go with headers + full exhaust. I hate drone, and going past 80 in stock form it starts getting annoying for longer drives. I wouldn't want to be sitting at 4k rpm in 6th crusing with a full exhaust & header

Also: MPGs

ohhh

so you want a quiet racecar that's easy on gas

k

gotcha

[reeves]

Originally Posted by mrk1

Bump up the final drive to 4.44 or 4.55. Won't give you a dyno to brag about but keeps you in the power you have more often. Should make it much easier to stay above the dip.

What's the difference between doing this and simply driving with your tranny in a lower gear? Like driving in 5th gear instead of 6th on the highway? I'm asking seriously.. isn't this pretty much what a higher final drive does?

[mrk1]

Originally Posted by reeves

What's the difference between doing this and simply driving with your tranny in a lower gear? Like driving in 5th gear instead of 6th on the highway? I'm asking seriously.. isn't this pretty much what a higher final drive does?

5th instead of 6th on the highway is similar to the effects of a new final drive, but not exactly. Dropping a gear would have a much more drastic change on rpm you would be driving at.

Having the final drive allows you to use all the available gears while keeping the engine within its power band. The numerical ratio change also results in more torque, about 10-15% (quoted from ft86speedfactory.com description of 4.44). Since the power is always going through the final drive that increase can be felt through the entire rev range. This is very noticeable when launching or even leaving a stop light. The car just feels much more eager to rev and go.

[Walldodger]

Originally Posted by CSI:86

we only have 100RON (at certain servos)

Who's selling 100 octane in Australia these days? Shell and Caltex used to but stopped some years go.

[CSI:86]

Originally Posted by Walldodger

Who's selling 100 octane in Australia these days? Shell and Caltex used to but stopped some years go.

One place i know is on Flushcombe Rd, Blacktown, a United Petrol Station, and that fuel is dyno proven to have more power. Friend's skyline was run in at 194kw with the United 100RON vs 187kw with BP98.

[troek]

there's starting to be more companys selling final drives at more reasonable prices too. 1200 for the cusco one is a little hard to swallow. although its much cheaper for me to pick up over here.