N/a Preformance Upgrades

[unarmed_skyline]

I like most of you guys reading this bought a non turbo skyline, i bought mine because of p plater restrictions but im still really happy with it, ive got a 1994 r33 gts25 drives like a dream.

Anyways in a search to think of things to do to my car i have found a lot of ideas that havent really been discussed very much on here mainly because everybody just says slap a turbo on it or do an engine swap

so heres some things that might help; REMEMBER to always research for yourself what you want to do and what to buy, sometimes listening to friends that may not no what their talking about can be very dangourous

First of all let the car breath:

Get a nice zorst - there are shops that will make you up custom cat back or with high flow cats ect for relitivly cheep ($300-800) or there are some jap options out there that will most likely be a little bit better preformance as there is rnd on them but they cost an arm and a leg ($1200+) n will probably have to get sent from japan.

Also look at getting extractors i have only heard of 2 different types one i think was coby exctractors and they were going for about $350 and then there is a jap version out there for about $1500.

Next look into doing something with the intake

: High flow panel filters (K&n apexi ect) are highly reckemended as people believe they give more power because there was a lot of rnd in the factory system and the factory system keeps the heat out expect to pay around $100 for a good quality item

: Pod filter: now make sure you buy or make a heat sheild for it the heat in the engine will take away preformance, expact about $50- $200 for the pod you can make your own heat sheilding for around $20 or there are Cai boxs to mount the pod in for around $150-250.

Now the car breaths

: Cam gears give you quite a bit of grunt sometimes some people say they more move your power band around but they are a good upgrade you will notice a bit different if tuned well. but will most likely be ilagal due to epa reasons.

: Ecu's are a good upgrade will give you more tuning ability, when buying an ecu you will have to thinjk what you want to do with the car, if you are happy with how it preforms and only want a little bit extra and want a little bit of saftey look into getting some sort of piggy bak computer (apexi safc2, greddy, ect) they will be about $300-900 and will need to be tuned after insalation, if you are going to take the car further to bigger better things ie. turboing, supercharging, rb30de build, engine rebuild,ect you will most likely need a stand alone system, look carfully what you might need the computer to do in future projects when choosing the computer as they are quite pricy $1000+

lighten the drive train:

I havent been able to find much disscussion on this on sau but there is a few options out there.

You drive train robbs a lot of engine power, the problem with lightening is that if you lighten your drive train too much you will loose some street drivability and effect your idle so research well when doing this.

: lightened tail shaft: there are a few different tail shafts out there which weigh about half of the standard weight i think the stock item is about 14kgs and you can pick lightened ones up for around $550 the weigh around 6-8 kgs bouns with this is it is diy only about 8 bolts to it, this will help the car rev quicker

: lightened flywheels are very common mods they cost around $450+ there are different types and weights out there this is a good idea to do if your already replacing your clutch as yyou have to drop the gear box to replace the flywheel,

: you can also lighten your pully system on this is a good mod because you lighten the strain on the crank and how much load the accessories take from your power, i havent looked into this much so not sure the about the cons

: fuel system mods look around you might not need to do this unless you hit acertain amount of power, but you can get new fuel pumps injectors fuel rails fuel regs, you can use any of the turbo items for these as they are bolt on bigger replacments.

This is the list of cheaper mods that can be done

other options are

Complete custom intake systems, you can buy an adaptor plate to be ablle to run gtr hex throttles (6 throttle bodies) you can then buy trumpets or throttle horns to put ontop of the hex throttle system and you will have a really nice setup sucking a lot of air all thought if you do this you may have to get a new ecu that suports not having an afm.

Another common mod is modifying a ford xf throttle body as its bigger = mor air = more power

or there have been custom twin throttle body set-ups done.

Engine rebuilds - there are na parts for builds out there they just harder to find

Rb30de build - talk to some of the guys round here there are i think 2 or 3 people who have done it and loved the torque produced from this

and then if all these na mods arnt enough you could alwayz put a turbo, superchager or NOS on or drop in a v8.

sorry for the essay but i hope this will help some of the guysout there considering modifying there na's

NO TURBO = NO LAG mmm. With the right mods you can get you na to power levels above stock or mild moded turbos but dont expect anywhere neer the power they get with the same amout of money, non-turbo are more expencive to mod and have less total potentential

[SKiT_R31]

Good writeup...

But there are a few things you've forgotten to mention...

how fast a car goes isnt always about the power it makes...

after you do your intake+exahust+ecu modifications, a way to make the car go faster is to change the gear ratio's, so for example if you have one of the older skylines (R31) with the 3.7 or 3.89 gear ratio's you can upgrade to 4.11 etc etc.

not syure about imports but i think there was a couple different types to chose from?

Also you can get moving quicker if your able to launch at a higher RPM, so for that, if you dont already have one, get an LSD and a good one at that. With this, also to launch at higher rpm's, maybe wider than stock tires etc would be handy...

Another one is weight reduction, remove that old AC that you dont use, sound deadening, ligher carpet/seats etc etc.

theres more to cars performance than just power...

But anyway, if ou think about it, an N/A Skyline, with a good intake (inc bigger throttlebody), Good flowing well made exaust (like mandrel with high flow's etc) short gearing, light chassis, good launching with grip, and a proper dyno tuned ECU, especially for those on there p's - why would you want anything more

And dont forget about suspension....

[NA power]

i am goin to start moding my Rb25, i would like to Put some Heavyer Cams in Ive got the zorst and im goin to get a good pod setup.

Dose anyone no any companys that make a Good set of cams for the Rb25????

[Eug]

But anyway, if ou think about it, an N/A Skyline, with a good intake (inc bigger throttlebody), Good flowing well made exaust (like mandrel with high flow's etc) short gearing, light chassis, good launching with grip, and a proper dyno tuned ECU, especially for those on there p's - why would you want anything more

And dont forget about suspension....

that is probably more true right now than it ever will be especially with the rising fuel costs.

yes i am being biased here, but sometimes a well balanced economic car is much more of a pleasure to drive than a car making 200rwkw and chirps the rear wheels everytime you change gears, etc.

good write up

[BADR33]

yeah good write up. i think a well sorted NA can be as much fun if not more fun then a turbo.

my rb30de can keep up with midly modifyd r32 gtst

getting a LSD is a huge advangage. changing the diff to a higher ratio helps with accleration. i noticed this when changed my diff from 4.0 to 4.3.. but it makes your speedo read higher then your doing.

another very cheep option for atleast r33 is to swap your exhuast for a rb25det exhuast. if you can get the bigger cat its a bonus.. but its a 2.5" exhuast. not sure if its crushed or mandrel. but its quite tidy looking. me and my mate who have done it have only spent between $150 and $200 to buy and get them fitted.

it is torque that makes your car move and its what you feel.. so you have to have a ballance between torque and top end power..

coby extractors are good. i noticed a good difference when i got them fitted to my rb20e..

good suspension makes a huge difference for everything. if you want your car to sit alot flatter in the corners get some bigger sway bars

[b.]

I'd love to do an RB25 with individual throttle bodies in a R32. Imagine the sound mmm...

[Eug]

I'd love to do an RB25 with individual throttle bodies in a R32. Imagine the sound mmm...

that would be sweet, but if gonna go all out with trumpets an RB30DE would be prime..

10000rpm, a nice set of extractors and exhaust and it'll make anyone cream

[unarmed_skyline]

Skitzo thanks for mentioning gear ratios and diffs and stuff i totaly forgot to put them in, And yea your suspention, tyres and brake set-up are very important especially if you want to take the car out on the circuts, drifting (or even drags for u straight line boys)

The better the car can handle corners at speed makes a massive difference.

[Bro'Duh]

Dude i like the info you provided and few other posts. though i have a r33 non turbo i plan on getting a gtr at the end of the year.

[scathing]

But anyway, if ou think about it, an N/A Skyline, with a good intake (inc bigger throttlebody), Good flowing well made exaust (like mandrel with high flow's etc) short gearing, light chassis, good launching with grip, and a proper dyno tuned ECU, especially for those on there p's - why would you want anything more

that is probably more true right now than it ever will be especially with the rising fuel costs.

A car with shorter gearing, NA mods (like big cams and the rest) and drivetrain weight reduction will make the car less fuel efficient than a low-blow turbo making the same power, especially around town.

Aside from having a higher cruising RPM due to the fact that your gearing is shorter and you don't have as much rotational inertia in the drivetrain, the loss of low end means you have to rev the engine harder to go anywhere.

When I switched to a lightweight flywheel in the Z my fuel economy decreased. I couldn't hold 6th gear in places where I did with the OEM flywheel without lugging the engine, so I've had to use 5th a lot more.

A mate who put a 3.9:1 final drive (from our OEM 3.5:1) had similar fuel issues. The engine was a lot more willing to rev and the car was a lot quicker, but he saw the difference at the pump. He's now rebuilt the bottom and gone to a bigger cam, which has exacerbated the issue.

That said, another guy in Melbourne who put a twin turbo kit on his car (with the OEM flywheel and final drive) noticed a marked improvement in fuel economy when commuting. He could leave the car in higher gears around town and just ride the torque curve.

Of course, once he opens the taps he may as well punch a hole in his fuel tank. But its his choice. For us NA tuners, we don't have a choice of economy or speed.

[SKiT_R31]

That is true to some degree, especially with a cam upgrade, but i didnt mention that before...

A cam upgrade wil definately negatively effect fuel economy/efficiency but its onyl thingss like this (things that change how the car actually drives) that should negatively effect efficiency.

Having a lighter car, will obviously help, im not sure about the lightened fly wheel issue, maybe in your case, but in the case of most of us with 5spd boxes, i cant see it doing any bad.

With shortened ratio's yes to a point you will lose highway economy but its not that much, i think from a 3.7 ratio to a 4.11 its about 350ish rpm at 110kmph. But you can gain efficiency in city driving etc, because you have the option to use a higher gear without the car labouring etc.

generally making the engine spin more freely, like removing AC, switching to twin thermos etc will all help economy slightly, as would raising the compression etc.

TRhings like porting and polishing, bigger throttlebody+intake etc shouldnt negatively effect efficiency at all unless you use that extra flow (i.e. give it to it).

Thats my veiw on it anyway...

also with gearing, if you notice, sitting at a steady rpm in a lower gear (i.e. 3000rpm in 4th instead of 2300rpm in 5th -example just made up figures) sitting on real time on the trip computer, there isnt tooo much difference (maybe ~ 0.3-4L/100 max) as its more in its power curve and needs less actual throttle, unless you do heaps of long highway trips, i cant see it effecting things too much... also you have to make sure you do shift that little bit earlier, it could also be drinking more because your waiting te same amount of time as you were before, before shifting, therefore revving it more etc - becasue inface you should almost be able to shortshift it a little bit as the gears in general are shorter.

ta

Edited July 28, 2006 by SKiTZ0

[thorpe84]

i think il just keep mine fairly stocko, no need to invest shitloads of money on 5 stud conversion tyres/rims/springs/zorst and whatever else when you go to sell it you will get shit all il just wait until im off my p's then go for a turbo 33 or hopefully 34 =)

[Specrzx]

Man reading all this just makes me want to stay N/A all the way... Just love the feeling of a straight out launch from an N/a. Got an R34 with K&N panel filter and stock zorst just with aftermarket tip. Great launch,

Dragged a 98 Rex with intercooler pod zorst and stell piping throughtout engine and beat it up until 2nd gear... Can you believe rear beat a 4wd on take off?...Yeh thinking about grunty sounded 34 something no one has... and if ever possible raise engine rpm in future...10000rpm or more =]___ endless revving.