We Need To Extract More Power

[nismoman18]

Ok i drove a turbo skyline today and the torque was massive, spinning wheels in 1-3rd gear, now in my NA i can spin em in first and a bit in 2nd, but in 3rd . Seriously what can be done to extract heaps more power from the NA engine without turbocharging, ive done filter and zorst. Will boring out and porting the head make a huge difference ? im sure our little 2.5 (or 2) litre engines can make a heap load of power if it is tinkered with fully! ne suggestions ppls ? and no one say BUY A TURBO cos i dont plan on doing that! Neone interested in extracting more power out of their engines, cos im gonna go to workshops and find out how much can really be extracted out of them

[NA_R33]

hey man, my car gives great 3rd gearies, and even better 1st to 2nd ones and currently all i have is a hks super dragger exaust, from 100 k's an hour it keeps up with most stock turbo cars. though there was one series 4 rx7 that put me to shame but he shot two 3 ft flames out his two exausts when he cracked 4th so i thought then i was down and backed off haha, in the next few weeks i should have a K n N high flow filter insert an Apexi S-AFC and those coby extractors fitted, ill get it all dyno'd and let u guys know how it goes. would expecting 20kw extra be stretching it??

[Nismodified]

huge cams and ported heads to match.

this will eventuate in heaps more revs, and will increase power.

we will never have the same amount of torque as as turbo(without forced induction of some sort), but if we can produce peak torque very high in th rev range, u get the power.

maybe stroking the engine to 2.7-2.8 liters while maintaining reseasonable revs would produce some very attrative figures

[nismoman18]

shit went for a drive tonite, cold air makes such a diffrence cos it was going realy fast, counted 0-100 in 6 seconds just counting by mouth, and loss of traction with new tyres lol, but not like ur car NA_33, maybe i should flat shift it into third!

[NA_R33]

yeah man, thats how mine does it i have a strengthened turbo clutch so theres no slip at all, works a treat!!!

[Nismodified]

Originally posted by nismoman18

shit went for a drive tonite, cold air makes such a diffrence

to my suprise it gets quite hot under our bonnets.

i just added a self designed and made airbox to suit my pod filter

added some cold air induction from beneath, and it seems to be working to a treat.

there is definatly some more top end, the tacho rushes really hard in the last 1500-2000 rpm (which is where it counts)

[nismoman18]

my cold air is just pod filter sitting in the front bar where the intercoller goes on turbo cars

[slip]

nismoman - cams, headwork, tuned ecu, extractors/full exhaust (designed for power and not sound), higher compression pistons (11.5:1- 12:1 maybe) bore the motor out, have it blueprinted, fully balanced, stroke it, make the intake charge as cool as possible.

You could opt for a 6 butterfly throttle system like the GTR's have, these are popular for hardcore n/a motors.

The above mods would end up costing bucketloads. Lots. Heaps.

You are better off buying a centrifugal supercharger, possibly fitting a decomp plate, intercooler, ecu and injectors in my opinion.

More power from n/a costs $$$ for relatively small gains usually in the skyline world.

[Guest Boxhead]

i would have to think a thermo fan would make a diff, i know i just put one on my turbo, but it made a diff, and i rekon the principle would be the same for n/a... without going for outright power, you can still make it quicker, eg a lightened flywheel sorta ideas..

they shoudl increase acceleration... or even maybe a auto diff.

[nismoman18]

hey guys thanks for the info, i was thinking the 6 throttle bodies however that would cost a shit load of fuel as well, maybe in the future. Boxhead where does the thermo fan go ? yeah lightened flywheel sounds like a next modification. but ur right, Shit load of money, maybe i will swap for a turbo

[Guest Boxhead]

thermo fan just replaces your clutch fan... basically its electric instead of using your engine to powe r the fan,

the clutch fan is the big fan at the front that cools radiator..

i got the top of the line 'ice' model 16' and it feels fine.. but $200 bucks.. ohwell.

[Revhead]

Why would six throttle bodies cost more in fuel? It'll give better response because the throttle butterflies are placed closer to the valves, but shouldn't affect fuel economy at all.

Agree with slip though, if you want good performance from a NA motor, you'd better be willing to fork out some serious cash compared to the same performance from forced induction.

For 50hp over dead stock

NA: Extractors, full exhaust, headwork, perhaps shave the head for a bit more compression. You've altered the characteristics of the engine so you should remap the ECU. At a guess that might give you 50hp, I dunno off the top of my head.

Turbo: Cat back or turbo back exhaust, wastegate bleed.

[Guest neoGT-25]

Hey, how much do you guys think that throttle boddies and trumpets for a RB25DE would cost?

my to do mod list goes like this

* Cobe Extractors

* Box For Pod With Cold Air

* Throttle Boddies W/ Trumpets

* A'PEXi SAFC

* Dyno Tune

already got

* Kakimoto 2.3/4" cat back exhaust system

* Pod filter

[nismoman18]

well i read on fullboost or sumwhere that more throttle bodies uses more petrol like the sr20det on a silvia compare to an sr20det on a pulsar GTIR, but yeah i see your point!

[Junior Zilla]

NA_R33, how much was ya HKS exhaust?

[NA_R33]

it came on my car but ive seen them advertised for around 1500 dollars, not a cheapy. Its not a real loud exaust but gives the car a nice deep note, and apparently adds between 12 and 18kw's "apparently" id like to see dyno figures.

[Junior Zilla]

ok well the truth is theyre worth in excess of $2000, my mate payed was quoted $4000 late last year

i dont know how true this info is but this is what ive been told

[Nismodified]

ive seen various exhaust for our cars for about 600-800 us, cat back.

4000 seems rather steep, but then again some fujitsubu extractors cost 2400AUD, so including cat back, its about right.

[Guest Boxhead]

guys, previously with my old n/a i was thinking about getting a good exhuast... basically i was told by many here, plus the boys at subzero that it isnt worth spending the big dollars on that department, as mandrel bends wont matter that much on an n/a car... your local muffler joint should be able to make you one..

[Junior Zilla]

i dont know much about exhausts, but i know his is 4" from the turbo to the muffler.

HKS Super Dragger.

What exhausts does everyone here have on at the moment?