ACE Header Independent Testing Results and Review - 199.6WHP on CA 91 Octane

[steve99]

Their is also an rpm vs load limit table

over about 3000 rpm load limit stock is set to 1.3
at about 1000 its about 0.8 load limit rising to about 1.1 at 2400 rpm

stops it running pig rich if you go wot at low rpm as it just limits load to the load limit regardless of what actual load is

[Kodename47]

The stock tune will also have a certain amount of headroom for the LTFT to lean up the mixture a little I reckon. The open loop fuel map isn't necessarily the target AFR, it's just the means towards a desired AFR.

[steve99]

Originally Posted by Kodename47

The stock tune will also have a certain amount of headroom for the LTFT to lean up the mixture a little I reckon. The open loop fuel map isn't necessarily the target AFR, it's just the means towards a desired AFR.

most stock cars run AFR down into the 10,s like @Tim Radley stock car on a tailpipe afr sensor, you just dont see it if you use the stock o2 sensor for readings using ecutek,tactrix,oft ect as its only calibrated to about 11.8 at richest (from memory) in stock tune.

yep the LTFT will adjust AFR a bit , but they all seem to run pretty darn rich high rpm stock, pretty sure that how most intakes are "making power" on stock cars just leans the top end a bit.

lot of tuners expand the range its seems to be quite a reasonably "wideband" enough for NA guys anyway

[350matt]

My only objection to this otherwise excellent design is the small (63mm) outlet
if this could be a 3" exit to match up to a 3" catted midpipe ( not sure where this pipe is coming from by the way) then its would be a marvellous forced induction option

[CSG Mike]

Originally Posted by 350matt

My only objection to this otherwise excellent design is the small (63mm) outlet
if this could be a 3" exit to match up to a 3" catted midpipe ( not sure where this pipe is coming from by the way) then its would be a marvellous forced induction option

I don't see the issue; we get our s2ks up to 500+ crank horsepower, supercharged, also on a 63mm outlet.

Exhaust piping size doesn't affect SC cars as much as Turbo cars, and I doubt turbo cars will be using this header.

[Rabbit of Caerbonnog]

@CSG Mike, do y'all offer remote EcuTek tunes for the header yet? I currently have the OFT but I doubt any OTS OFT tune will maximize the headers potential.

[CSG Mike]

Originally Posted by Rabbit of Caerbonnog

@CSG Mike, do y'all offer remote EcuTek tunes for the header yet? I currently have the OFT but I doubt any OTS OFT tune will maximize the headers potential.

Not yet, but it's in the works.

[FrX]

Originally Posted by CSG Mike

Not yet, but it's in the works.

I would be totally interested in a tune to complement the header, as well.

[350matt]

Originally Posted by CSG Mike

I don't see the issue; we get our s2ks up to 500+ crank horsepower, supercharged, also on a 63mm outlet.

Exhaust piping size doesn't affect SC cars as much as Turbo cars, and I doubt turbo cars will be using this header.

sorry what?
power is power no matter how you achieve it, all engines need to breathe and 500bhp needs a big pipe,
and 350- 400 bhp is time to go up a size from 2.5 to 3"

yes you no doubt achieved this figure but did you test a larger pipe ? might have made 525Bhp then?

[CSG Mike]

Originally Posted by 350matt

sorry what?
power is power no matter how you achieve it, all engines need to breathe and 500bhp needs a big pipe,
and 350- 400 bhp is time to go up a size from 2.5 to 3"

yes you no doubt achieved this figure but did you test a larger pipe ? might have made 525Bhp then?

We sure did. 63-70mm ID yielded about 1 lb/ft through the entire powerband. 70-75mm yielded nothing. No point in all that extra noise for basically minimal returns. It's amazing what a properly engineered exhaust system can do.

[mokinbird87]

good god.. i`m a huge fan of the boxer rumble, but this thing just sounds awesome...

@1:58

[ame="https://www.youtube.com/watch?v=-aMShTgAG00"]ACE Header & Vintage Speed - YouTube[/ame]

[Coheed]

Originally Posted by steve99

Your wasting money buying this (or most other headers) without getting a tune to suit. you will likely only see about 1\3 of the possible gain without a tune.
even most aftermarket catted headers will thow a cel eventually
02 spacer on second 02 sensor may work but its an expensive header and would be wasted without proper tunning
in the tune they will disable cel code P0420 cat efficiency

If the cat monitor is disabled will this cause the monitor to never set to pass a state I/M?

Reason I ask, my buddy with his EvoX can't pass UT emissions with his tune because it disabled the rear O2 sensor, and although the CEL never comes on, he can't pass the emissions test because the OBD2 computer doesn't show it's ready.

I love the header, but it this is purely for offroad or race use I cannot consider it. Perhaps relocating the O2 to behind the 2nd cat would suffice?

[steve99]

Originally Posted by Coheed

If the cat monitor is disabled will this cause the monitor to never set to pass a state I/M?

Reason I ask, my buddy with his EvoX can't pass UT emissions with his tune because it disabled the rear O2 sensor, and although the CEL never comes on, he can't pass the emissions test because the OBD2 computer doesn't show it's ready.

I love the header, but it this is purely for offroad or race use I cannot consider it. Perhaps relocating the O2 to behind the 2nd cat would suffice?

We dont get those yearly checks here luckily. so I am not 100% on this subject.

As I understand it their is a difference between disabling the rear o2 sensor and disabling the CEL code P0420

When you just disable the CEL code like P0420 it just stop the ECU triggering a CEL for that particular error cat efficiency.

The 02 sensor is still enabled and its signals are still getting to ECU and all its other functionality other than just triggering that particular CEL code is still working.

Most tunes will just disable the CEL code P0420 not disable the 02 sensor entirely.

If your running a flex fuel kit they can use the rear 02 sensor input and re-assign it as the input for the flex fuel sensor, in this case they would disable the rear 02 sensor completly.

[sw20kosh]

Originally Posted by steve99

We dont get those yearly checks here luckily. so I am not 100% on this subject.

As I understand it their is a difference between disabling the rear o2 sensor and disabling the CEL code P0420

When you just disable the CEL code like P0420 it just stop the ECU triggering a CEL for that particular error cat efficiency.

The 02 sensor is still enabled and its signals are still getting to ECU and all its other functionality other than just triggering that particular CEL code is still working.

Most tunes will just disable the CEL code P0420 not disable the 02 sensor entirely.

If your running a flex fuel kit they can use the rear 02 sensor input and re-assign it as the input for the flex fuel sensor, in this case they would disable the rear 02 sensor completly.

Still won't pass. Can't pass without a cat in between the O2 sensors.