Buying a Gen 4 Legacy - Fuel question

[Guest]

Hi guys, i've been reading Clubsub for some time, and have done a lot of searching as I research buying a 2003-2006 Legacy 2.0 turbo or 3.0 NA - have a budget of $17K (some of which I hope to have left for a few tweaks!).

Now, I'm a bit torn between getting a GT / GTB and a 3.0R/B - I've driven both, and appreciate the qualities of each (boost or smooth power delivery) but love the standard look of the GTB's (and the fact all JDM GTB's and GT's come with Bilsteins) - they look great with the front bumper and 18's.

The 3.0R's look a little plainer although nicer with a lip and grill. Need to pay extra for a 3.0R spc B to get the Bilsteins too which I understand work better with lowered springs.

I'm not concerned about fuel economy and will be getting a mech warranty, so not too fussed about the added servicing (frequency and cambelt) of the 2.0 Turbo. I look after my cars, and understand the twin scrolls are pretty good with the right maintanence.

Now, my personal issue with the Turbo is I can unfortunately only run on 95 (Shell V Power) - i'm in Auckland, but have a company fuel card for shell / Z so won't be able to access 98 which is preferred for Turbos. Not that i'm complaining about free gas! I just wish it was free 98...

Searching the Web and clubsub it seems many people run them on 95, but 98 is always the best option, espcially for JDM 2.0 turbos - Is it possible to get a turbo remapped for 95 or should I just get a 3.0R and spend my money on making it look a little better?

[Wiretap]

Both will run 95 okay. Best to re-map both of them though, the 3.0R runs a 10.7:1 CR so really is intended for 98 too.

[mondo]

I have a 04 GTB, I run 95 with no problems.I ran 98 and there was no difference(except to the wallet!).I did find that I got best fuel eco with caltex 95

[Guest]

you could get the octane booster that repco sell put that in my tank and noticed a difference

[Kiwi_Fozze]

with a reflash, the turbo'd model should take to running 95 better than the n/a at those compression levels.

[paulngui]

 mondo said:

I have a 04 GTB, I run 95 with no problems.I ran 98 and there was no difference(except to the wallet!).I did find that I got best fuel eco with caltex 95

That's interesting, I would've thought 95 would give worse economy for sure.

[Wiretap]

 paulngui']

[quote name='mondo said:

I have a 04 GTB, I run 95 with no problems.I ran 98 and there was no difference(except to the wallet!).I did find that I got best fuel eco with caltex 95

/quote]

That's interesting, I would've thought 95 would give worse economy for sure.

95 will give about 16-20% less power (according to dyno sheets found online), which will mean a bit more foot pedal so I'd say 12-15% worse economy.

[Joker]

theory is ECU learns the 95/adjusts timing, and take a while to relearn the good habits of 98, ECU reset required to regain any lost power rather than expecting instant change from a single tank

there is a thread in FAQ on how to "fast teach" your ecu for max power

[Guest]

Thanks guys - 20% drop in power, sheesh!

So octane rating is related to compression? I have a 2.0 Vtec currently which runs 11.0:1 compression and dosnt seem to mind 95 (it's a torqueless wonder though)

[Wiretap]

 Sosua said:

Thanks guys - 20% drop in power, sheesh!

So octane rating is related to compression? I have a 2.0 Vtec currently which runs 11.0:1 compression and dosnt seem to mind 95 (it's a torqueless wonder though)

You need a high quality fuel to reach 'mean best torque' on a high compression engine. Your honda is distributed ignition so in reality it's going to have 'safe' timing which is going to be nowhere near MBT.

[Guest]

Any ideas on the cost to remap for 95?

Not dying to spend a grand on a performance tune, just to safely run 95 and not lose too much power...

[Wiretap]

 Sosua said:

Any ideas on the cost to remap for 95?

Not dying to spend a grand on a performance tune, just to safely run 95 and not lose too much power...

It will, unfortunately, cost about the same as a 'performance tune' as you don't pay per kilowatt of output.

You can run 95 safely in the 3.0R that's for certain but I'm not 100% on the GT as there have been mixed results.

[Kiwi_Fozze]

there are a few people online who can talk you through reflashing, if you are confident enough you can reflash it yourself. there are tune maps available online too...

it can be done very inexpensively.....but it is by no means a dyno tune.

[Wiretap]

 kwi_fozze said:

there are a few people online who can talk you through reflashing, if you are confident enough you can reflash it yourself. there are tune maps available online too...

it can be done very inexpensively.....but it is by no means a dyno tune.

The 'reflash' I'm referring to in this case is re-flashing with an appropriately tuned (dyno or road, doesn't matter) map. Not a generic base map, those are base maps for a reason, they're what you base your tune on, certainly not a finished product and it is not safe to consider them as such.

[Joker]

wouldnt bother : just run 95 and for get about it "newer" cars like that are not as upset over it than the pre 2000's

[Wiretap]

 JoKer said:

wouldnt bother : just run 95 and for get about it "newer" cars like that are not as upset over it than the pre 2000's

The knock control strategy actually hasn't changed for what it's worth.

[Joker]

still not worth the effort of a reflash thou aye

[Guest]

Thanks all, so it seems the verdict is its not ideal but not a killer - I may look at 3.0r's (seem to be a few well priced 6 speeds around) in that case unless a really good GTB pops up.

Is it true the Bilsteins work better with a lowered spring - I'm looking at a moderate drop progressive spring like H&R.

Had enough of my Jamex super lows on crappy stock Honda shocks, no fun...

[Wiretap]

 Sosua said:

Thanks all, so it seems the verdict is its not ideal but not a killer - I may look at 3.0r's (seem to be a few well priced 6 speeds around) in that case unless a really good GTB pops up.

Is it true the Bilsteins work better with a lowered spring - I'm looking at a moderate drop progressive spring like H&R.

Had enough of my Jamex super lows on crappy stock Honda shocks, no fun...

Most people who buy Gen4s don't lower them as they're not quite cheap enough to reach 'that market segment' yet. However I wouldn't see why Bilsteins would be better than KYBs in terms of lowering, especially seeing as they are likely to have the same type of spring on them anyway (if maybe a slightly different rate)

[Guest]

Thanks - I'm not talking about 'slamming' it, just reducing the wheel to fender gap an inch or so.

From reading a lot on LegacyGT.com, it seems the KYB equipped USDM GT's don't handle a lowered spring as well as the Bilstein equipped cars (JDM GTs and USDM spec B's).

A firmer shock is less likely to bottom out / wear out as fast with a lowered spring? I'm not sure, but it seemed to be the general concensus...

[Wiretap]

 Sosua said:

Thanks - I'm not talking about 'slamming' it, just reducing the wheel to fender gap an inch or so.

From reading a lot on LegacyGT.com, it seems the KYB equipped USDM GT's don't handle a lowered spring as well as the Bilstein equipped cars (JDM GTs and USDM spec B's).

A firmer shock is less likely to bottom out / wear out as fast with a lowered spring? I'm not sure, but it seemed to be the general concensus...

If I were you I'd be very wary of the stuff that people stateside talk about. There is an unbelievable amount of misinformation over there (for example, according to them the V3/4 2L Impreza bumper is only found on V4 STis, nothing else )

[GC8E2DD]

Get colour coded wheel arch extensions that close the gap.

[Joker]

24"s yo

[calibre]

 GC8E2DD said:

Get colour coded wheel arch extensions that close the gap.

where from? Ive been considering the same sort of drop on my 3.0r wagon, but this would be a preferable option.

[Guest]

Color coded wheel arch extensions? Surely you jest?

Larger wheels would do the same I guess, funny that the GTs and 3.0s seem to run 215/45/17 and the B specs 215/45/18 - wonder if the speedos are adjusted for the larger diameter...