why does a gx have 10bhp more than a gr?

[nairnman]

just reading through some articles and found that a gx replaced the gr and has 10bhp more? why is this if the engine is the same and can whatever it is be done to my prefacelift gr, many thanks

[Sebastian]

different Ecu and different exhaust setup than the Gr . and some uprated sensors
Not sure if the Gx is lighter also than the Gr

[nairnman]

so if i bought a ecu from a broken gx or bought new, would it just plug in? also what sensors as its the same engine? cheers for the speedy reply im all excited now lol

[goz_83]

abandoned your mivec ideas then?

[nairnman]

well with the mods i have and if i got 10bhp more just by swapping a ecu then, i go the easy route haha

[colm_mcm]

Gx has different cat and exhaust I think

[nairnman]

do you have any pictures of the differences?

[colm_mcm]

have a look on camskill. My memory lets me down here, but as far as I remember, the GPX and GX both have a larger bore exhaust.

[nairnman]

my exhaust all the way through has a large diameter compared to other cars ive seen? so i do wonder if mine has a gx exhaust

[colm_mcm]

You really should get your car dyno'd

[nairnman]

will do m8 at some point, too many things i want to find out about this car lol

[Myfeckin FTO]

You're not gonna feel 10bhp on your ar5e dyno!

As suggested get your FTO on a rolling road and get your power at the wheels.
Then add decat larger bore exhaust, induction (with a cold air feed) - set of Denso Iridium plugs, upgrade the fuel pump (and perhaps a fuel pressure regulator), get it all mapped and I reckon you'll see 10-15bhp of an improvement.

NA tuning ain't cheap and the power gains may not be worth the money spent - the above is as far as I would go to tune an FTO and some would say thats too far for too little gain.

My advice - sell your GR - buy a Manual Mivec - cheaper route to better performance.

[goz_83]

I agree there with Shane, but understand you want to keep your GR as you have put work into it. If you're really attached to your gr, You could buy a manual mivec going cheap, or being broken; transplant the engine, exhaust and gearbox. If the mivec was in good nick, you could put your GR components into it and get it marked down on the logbook to sell it on as one piece. Or, you could break it and hopefully make your money back and perhaps even a small profit. It will be a lot of work and something I would not personally take on. Nearly every component is transferable, so you could, in theory swap everything from your GR into a manual mivec and it "might be" less trouble than the conversion mentioned at the start of my thread. Either way, its a headache and you'll need deep pockets to pay a garage, or a lot of help from a mate.

[CJ]

Aside from some minor changes to exhaust and the like, the extra 10bhp available on a GX can be directly attributed to more efficient ECU tuning (mainly governed by altered air/fuel ratios and more aggressive cam timing). Bear in mind that a/f ratio was based on using 100RON fuel, E5 is a close match in terms of octane rating but is down on calorific content i.e. you're not going to see the full 10 brake in reality.

I've not heard of anyone dropping a GX ECU into a GR (if it was that easy, it would likely be commonplace). That said, it may be achievable with some effort but not worth the effort unless you're comfortable with undertaking some pioneering work with respect to interrogating ECU signalling and output. I also read that the extra 10bhp in a GX is a myth (I seem to remember it begin mooted up by some in Eurospec in the UK but can remember the details).

[Sebastian]

We tested that on the drag strip , 96 manual gr versus 98 tip gx. The gr won

[nairnman]

im happy with the gr but always looking for more power, without the massive cost of turbo,s. imagine a line of 6 throttle bodies on top

[colm_mcm]

We tested that on the drag strip , 96 manual gr versus 98 tip gx. The gr won

Do you think the manual gearbox might have had just a teeeeny tiny bearing on that result?

[goz_83]

Was the gx driver fat? Could have made a difference