Increasing Performance of the H6

[dr20t]

I'm not offended. And I'm not having a crack at you or other h6 owners in any way.

I'm having a crack at Matt for perpetuating this crap that an unopened n/a h6 can make 200kw atw from headers, e85 and tune

[Swipez]

I'm not offended. And I'm not having a crack at you or other h6 owners in any way.

I'm having a crack at Matt for perpetuating this crap that an unopened n/a h6 can make 200kw atw from headers, e85 and tune

I never said it can make 200kw at the wheels. Never once said that. I said it can peak at around 240kw at the crank on E85. There is a big difference there. That translates into about 170-180ish kW at the wheels, (When on E85!). Please don't have a crack at Matt. He never once communicated that he has made anywhere over 180atwkw when tuning for absolute peak power. On a peak power tune, he was able to get 170-180 atw on E85. That's not THAT ridiculous. Come on bro, enjoy that we're able to do this to the H6!

[Housemusic1]

Ok, so another stupid question here.... Let's say you do tune for E85, new fuel pump, headers, etc... Would there be an issue if you are not able to put E85 in? Say, if you are on a road trip, and can't find a service station with E85, would you mess anything up by putting in a tank of premium gas? Again, based on the knowledge from this forum, my questions probably sounds stupid, but I'm very interested in the potential gains (even if it's just increase torque for the 2-5K RPM range) that can be had. Again, thanks for the help. Stop arguing, enjoy your Subaru!

[KiDo_Tuning]

Or another way to look at it is to say the h6 would make 480 flywheel kw's with 14.7psi of boost
Dunno about you, but haven't seen any turbo or supercharged h6 anywhere in the world make this sort of power - including completely forged and blueprinted big dollar machines.
Not hating on the h6 - love the engine as much as the next man (and infact would love a turbo'd ez30 over my 2.0 litre anyday of the week). But lets call a spade a spade and stop with this keyboard bullshit about making 30% more power on an n/a car from a tune.

So if the G88 built Twin Turbo H6 was retuned to make 285Kw@wheels on 9psi at peak power on 98 fuel? What would be its expected flywheel power output on 14.7psi at the crankshaft?

182Kw@wheels is the absolute MAXIMUM we have seen dyno tuning these things on E85 and that is currently in MULTIPLE cities and dynos across Australia... Also, I was not the first it seems as there is already a member on this forum from France who had a French tuner tune his H6 on E85 with similar results.

To put this into perspective Mick, I retuned a dead stock H6 Liberty in Adelaide with just my 98 base tune. Went to a dyno day and other than the dyno operator backing off early at 6400rpm, it made more power everywhere against a H6 that had been tuned with headers, full exhaust and tune from that same dyno operator.

[KiDo_Tuning]

Also, to put it into perspective Mick, drive a stock H6... all of the turbo lag, none of the turbo power delivery. Stock torque/power is basically 'dead' by 5500rpm so if the torque at 5500rpm can be held to 7000rpm(with a gain in torque in the midrange to fill it out) then obviously since holding that same torque for 30% longer rpm wise, you would pick up 30% more power... Even better if you get more torque out of it as well right?

[Housemusic1]

So just to confirm, your dyno numbers are strictly NA H6, not a turbo, correct? I keep seeing people talk about boost, and psi, in relation to H6, but you wouldn't have "boost" on a NA engine. Again, I'm in the US, so I know they have different H6 platforms in Australia, but non of them are factory turbo, correct?

[Swipez]

So just to confirm, your dyno numbers are strictly NA H6, not a turbo, correct? I keep seeing people talk about boost, and psi, in relation to H6, but you wouldn't have "boost" on a NA engine. Again, I'm in the US, so I know they have different H6 platforms in Australia, but non of them are factory turbo, correct?

Correct, these figures we're talking about are achieved on n/a engines. I guess that's what the 'argument' is about.

[Swipez]

Ok, so another stupid question here.... Let's say you do tune for E85, new fuel pump, headers, etc... Would there be an issue if you are not able to put E85 in? Say, if you are on a road trip, and can't find a service station with E85, would you mess anything up by putting in a tank of premium gas? Again, based on the knowledge from this forum, my questions probably sounds stupid, but I'm very interested in the potential gains (even if it's just increase torque for the 2-5K RPM range) that can be had. Again, thanks for the help. Stop arguing, enjoy your Subaru!

Flex tune. Means you can put any blend to your liking of E85 or 98 ULP.

[Housemusic1]

Ok, so another stupid question here.... Let's say you do tune for E85, new fuel pump, headers, etc... Would there be an issue if you are not able to put E85 in? Say, if you are on a road trip, and can't find a service station with E85, would you mess anything up by putting in a tank of premium gas? Again, based on the knowledge from this forum, my questions probably sounds stupid, but I'm very interested in the potential gains (even if it's just increase torque for the 2-5K RPM range) that can be had. Again, thanks for the help. Stop arguing, enjoy your Subaru!

Flex tune. Means you can put any blend to your liking of E85 or 98 ULP.

Flex tune ya say? Hmmmmm, that sounds interesting.

[BillyCorgi]

Flex tune ya say? Hmmmmm, that sounds interesting.

Better than Interesting!

[Swipez]

Flex tune ya say? Hmmmmm, that sounds interesting.

Better than Interesting!

You've got that right Billy!

Corn juice to get us there fast,
98 to ensure we can get back.

[Housemusic1]

Awesome. I will have to see if my current tuner has done a flex tune. Once the snow is gone, the Raptors are getting welded up, and it will be time for some fun.

[alexeiwoody]

Do you notice any real power gains with E85 on a NA engine? Obviously they gains are not like a turbo engine on E85, but I'm just wondering if the cost can be justified. Car is modestly tuned right now, will have Raptor Headers, Raptor CAI, and full exhaust in March. E85 is everywhere in my area.

I'm gonna use power @ the crank as an example of the power gains. Stock car has 180kw, if someone like Matt Mcleod gives it an E85 flex tune, he'll do a max power tune once you're at about 80% ethanol in the fuel tank. (that'll be about the max ethanol percentage you'll ever get out of the pump). And he HAS seen figures over 240kw at the crank after tuning on E85. He has achieved these figures on a few people's H6's. So yes, you can achieve HUGE power gains on N/A with an E85 tune. You'll find that the stock tune is pretty darn conservative (and lazy). Matt will tune the stock negatives out of your h6, apply his own values, and will give you much more USEABLE torque (lower rpm torque), Greater outright power, throttle response, and all those good things simply by tuning it. He then has more tuning bandwidth when E85 is introduced. The fuel has a high knock threshold and will allow matt to get even higher power and torque figures throughout the whole rpm range. (Which is what makes a fast Street car). Matt is a God on these cars, 60kw peak gains just from a tune and a different fuel is nuts. And btw, ethanol is cheaper per litre. But NOT cheaper per kilometre. It'll burn 40% faster. Hence why flex fuel tunes are so useful.

And also, don't bother changing ANYTHING other than the fuel pump, and headers. Don't bother with a CAI, do not get bigger injectors, don't waste your money on other crap. It's not needed.

Swipez...it's great that you're excited about your H6. It is a great engine and the gen4 is a fantastic platform. I don't think anyone here is trying to claim otherwise.

These numbers you're quoting so religiously about crank power and others...they're just that - "quotes". Not only are they "not quite" proven, as dynos measure power/torque at the hubs/tyres and not at the crank, but some like the "40% more fuel usage" and "300kw at the crank with a supercharger" are wrong. If you don't mind - let's stick to numbers that have been measured reliably and proven many times - 180kwatw.

That is best case scenario with all the bolt ons + full E85 (as measured on a manual, take off about 20kw for an auto) and a considerable amount of $$. Yes, it's a pretty nice daily driver.

That is also the same peak that a bone stock GT gets with a TBE and maybe an cheap TMIC. 180kw on a manual, take off 20kw for the 5eat. Add a fuel pump, headers and E85? Suddenly you're well into 200kwatw+ territory with more torque and power everywhere (except maybe under 2000rpm! ) over a similarly modded H6. And it really shows up even on the bum dyno. Funny enough, Matt has quoted his customers 230kwatw on that setup. And then there was one bloke here who made 270kw at the rear (let's allow 10% extra power, so 230-240kw otherwise at all 4) on that setup. Oh and he was on 98. See how dyno figures also don't really solve anything and just create arguments?

If you guys really want to brag about how much power and torque you're making - post up some 1/4 slips. No one can argue with those (and are a lot more exciting to talk about than your crank numbers).

Check out Kiahatsiu's challenge thread. Lots of H6 owners had a go on the 1/4mile. Turns out - all of these "WRX beating" E85 H6s ran the same 1/4 as a stock WRX or worse.





TL:DR version: Enough shit talk, post up some slips.

[Swipez]

Do you notice any real power gains with E85 on a NA engine? Obviously they gains are not like a turbo engine on E85, but I'm just wondering if the cost can be justified. Car is modestly tuned right now, will have Raptor Headers, Raptor CAI, and full exhaust in March. E85 is everywhere in my area.

I'm gonna use power @ the crank as an example of the power gains. Stock car has 180kw, if someone like Matt Mcleod gives it an E85 flex tune, he'll do a max power tune once you're at about 80% ethanol in the fuel tank. (that'll be about the max ethanol percentage you'll ever get out of the pump). And he HAS seen figures over 240kw at the crank after tuning on E85. He has achieved these figures on a few people's H6's. So yes, you can achieve HUGE power gains on N/A with an E85 tune. You'll find that the stock tune is pretty darn conservative (and lazy). Matt will tune the stock negatives out of your h6, apply his own values, and will give you much more USEABLE torque (lower rpm torque), Greater outright power, throttle response, and all those good things simply by tuning it. He then has more tuning bandwidth when E85 is introduced. The fuel has a high knock threshold and will allow matt to get even higher power and torque figures throughout the whole rpm range. (Which is what makes a fast Street car). Matt is a God on these cars, 60kw peak gains just from a tune and a different fuel is nuts. And btw, ethanol is cheaper per litre. But NOT cheaper per kilometre. It'll burn 40% faster. Hence why flex fuel tunes are so useful.

And also, don't bother changing ANYTHING other than the fuel pump, and headers. Don't bother with a CAI, do not get bigger injectors, don't waste your money on other crap. It's not needed.

Swipez...it's great that you're excited about your H6. It is a great engine and the gen4 is a fantastic platform. I don't think anyone here is trying to claim otherwise.

These numbers you're quoting so religiously about crank power and others...they're just that - "quotes". Not only are they "not quite" proven, as dynos measure power/torque at the hubs/tyres and not at the crank, but some like the "40% more fuel usage" and "300kw at the crank with a supercharger" are wrong. If you don't mind - let's stick to numbers that have been measured reliably and proven many times - 180kwatw.

That is best case scenario with all the bolt ons + full E85 (as measured on a manual, take off about 20kw for an auto) and a considerable amount of $$. Yes, it's a pretty nice daily driver.

That is also the same peak that a bone stock GT gets with a TBE and maybe an cheap TMIC. 180kw on a manual, take off 20kw for the 5eat. Add a fuel pump, headers and E85? Suddenly you're well into 200kwatw+ territory with more torque and power everywhere (except maybe under 2000rpm! ) over a similarly modded H6. And it really shows up even on the bum dyno. Funny enough, Matt has quoted his customers 230kwatw on that setup. And then there was one bloke here who made 270kw at the rear (let's allow 10% extra power, so 230-240kw otherwise at all 4) on that setup. Oh and he was on 98. See how dyno figures also don't really solve anything and just create arguments?

If you guys really want to brag about how much power and torque you're making - post up some 1/4 slips. No one can argue with those (and are a lot more exciting to talk about than your crank numbers).

Check out Kiahatsiu's challenge thread. Lots of H6 owners had a go on the 1/4mile. Turns out - all of these "WRX beating" E85 H6s ran the same 1/4 as a stock WRX or worse.





TL:DR version: Enough shit talk, post up some slips.

I'm not trying to contest how much 'power' I'm making. I'm simply going off of Matt's experiences. He HAS logged 182atwkw. Not the 230 you just mentioned, don't know where you got that from. Anyway, I used crank power as a comparison to the stock number thrown out by subaru. Through Matt's experiences and knowledge, 180atwkw is around about 240 at the crank. That is all, you're assessing it too deeply. I think we've about settled the bout anyway. The H6 makes huge power/torque increases where you NEED it on the street. E85 = GOD JUICE, pair it with a tune and you've got yourself great gains on the h6.

[Swipez]

I'm not real happy at the fact that a few of us liberty owners are arguing instead of admiring what we can do with our cars. If we can't drive past each other and give the ol' salute to a fellow lib owner with utmost friendship and respect, then who can we do it to?

Come on. And if it makes you happy, once my car is tuned, I'll be going to the drags and giving it a good old go, I'm interested in street performance, not particularly drag racing on the strip.