GT86/GR86/BRZ

[rebel rebel]

I don't do track sessions, but most of my journeys are short. I don't get out much lately because of dialysis, however I do enjoy a drive along the coast on a weekly basis. It would be cool to give it a little bit more power. The Avo would still sit within the 260bhp limit.

Is there a way to monitor the auto gearbox condition?

 

[Steeps]

Might be possible to get a temp probe for the gearbox oil somehow but stage one I really wouldn't worry about it at all, especially as it's only for road use. The original Fensport demo car was a stage 1 Avo with full exhaust running 270bhp on the auto box, they've done a lot of work with another customer and their auto which is where they were finding the limits (got through a couple of boxes). FI will really help improve the auto because of the longer gearing compared to the manual. Stage 1, stock catback and a safe tune I really wouldn't worry about the limitations of the auto.

 

[rebel rebel]

I've just googled and found there's an auto transmission cooling kit that you can get. That with a temp gauge could be kinda cool and give me peace of mind.

 

[DereksDontRun]

All turbo kits remove the manifold (header) so you will lose the manifold cat, the 2nd cat is more than capable of handling MOT emissions but the lifespan is unknown, some cats have failed with supercharger setups on the stock manifold.

I'm waiting for the engine recall to consider going supercharged (rest of the car is Cosworth), I don't really need the extra power but with the extra noise of the exhaust I think it needs the power to match.

Removing the manifold cat is an MOT fail irrespective of emissions - so you need to go into it knowing it "should" fail, but most only look at emissions and possibly check there's a cat-shaped thing where the 2nd cat lives.

I thought that our RHD GT86's were more suited to supercharging, over turbo, as the steering column goes right were the turbo would ideally sit (and can on the LHD cars)?

 

[Nasher]

Yep it should fail simply for removing it if you go by the book. But since the underside of the car is covered in trays they can't confirm it's been removed, so can't fail it. The only thing you can see under the car is from overpipe back

 

[DereksDontRun]

aha, ace! so potentially the annoying advisory for being unable to see anything ;D

I've got another year on my M135i pcp, but already wondering what to do next... Really miss my old Mx5 and only really swapped to the 135 for space to carry a bike or 2. But, not have the complication of kid due next month. So, kinda wondering if gt86 might tick the box of "mx5, but more practical" - but with the step down in power from the 135i, I'm just wondering if I'll be bored without the top-down 2-seat novelty of the mx5. Supercharged gt86 looks like it might push the right buttons... How diy are the kits? any build blogs anywhere?

 

[Steeps]

The 2nd cat is still visible without moving trays for the MOT and good enough to pass emissions alone. Either cat will pass emissions, only starts to become an issue when you have a single sports cat as I found out (became a lucky dip on the day with emissions).

Supercharging is easier as you're not touching any of the exhaust, the problem is trying to get a larger bore exhaust which a tuned turbo kit would benefit from past the steering column knuckle. Lots of 2.5" pipes fit fine but you're probably going to get rubbing with 3", I've seen quite a few 3" overpipes fitted to cars and most of them have had to have some "modification" (large hammer) to give clearance for the knuckle on RHD cars. Most turbo kits for the 86 sit on the front then feed in to the overpipe.

The kits are DIY'able, here's the instructions for the Cosworth supercharger which I know a couple of owners have managed to do over a few weeks: http://1a8a0a7731808949ec7d-33d79809264fd8f465f395acab527149.r13.cf1.rackcdn.com/COS2_20046685.pdf

 

[Nasher]

If your on the wire using one cat, try some octane booster fuel additive on MOT day

 

[DereksDontRun]

The 2nd cat is still visible without moving trays for the MOT and good enough to pass emissions alone. Either cat will pass emissions, only starts to become an issue when you have a single sports cat as I found out (became a lucky dip on the day with emissions).

no - it's a MOT fail to remove any cat. If a car is supplied from factory with 2 cats it needs 2 cats to pass a MOT - this is a visual check only tho. It also needs to pass emissions on top. So, technically swapping the manifold to a catless one is a failure - you're just semi-safe due to the cover blocking the view...

 

[DB_SamX]

I have been thinking about selling my GT86 for a Focus ST2/ST3 of similar age. I see it as a sideways move.

I did a lot of driving last week, especially in Sutton, Greater London - soooo many speed humps. I think the hard ride, combined with the lack of practicality of cramped rear seats, and people (and me occasionally) moaning about how low it is is finally leading me to getting something with 4 doors and potentially more comfy. Not actually test driven a ST yet to get a fair comparison, but hopefully soon.

 

[rebel rebel]

The last thing I want to do is risk an MOT fail. This is too complicated for someone who doesn't know anything about cars, and just wants a little bit more speed.

 

[Nasher]

I have been thinking about selling my GT86 for a Focus ST2/ST3 of similar age. I see it as a sideways move.

I did a lot of driving last week, especially in Sutton, Greater London - soooo many speed humps. I think the hard ride, combined with the lack of practicality of cramped rear seats, and people (and me occasionally) moaning about how low it is is finally leading me to getting something with 4 doors and potentially more comfy. Not actually test driven a ST yet to get a fair comparison, but hopefully soon.

The GT86 is actually more comfortable than the STs, I've owned 2 of them. They have rock hard suspension like most hot hatches. The low center of gravity on the gt86 means it doesn't need that to corner flat.

 

[DereksDontRun]

The last thing I want to do is risk an MOT fail. This is too complicated for someone who doesn't know anything about cars, and just wants a little bit more speed.

So, look at supercharger instead of turbo

The supercharger option shouldn't need a cat removal - so, wont be the problem listed above (but, chances are, people happy to void warranties and mod enough to FI their car will likely swap out the exhaust manifold for a better one without the 1st cat - if available). A turbo will need the exhaust manifold (and 1st cat) removal tho - so technically all turbo gt86 are MOT naughty...

While, yes, the primary cat removal is technically an automatic MOT fail, it rarely happens, even with cars without a cover hiding away most of the engine-bay (it's only pedants and prats that even mention it ). It's more work for the MOT tester to go researching what cats are one what cars, and where they all sit - so it's a visual check that there's 1 someone along the exhaust and the emissions check. You'd be v unlucky to fail, especially with a tray along the underside of the car. (but, sod's law could prevail, and once it's marked on the mot failure, you know that every mot tester and purchaser from then odd will likely check...)

 

[rebel rebel]

The supercharger was my first thought, but then I wondered whether having an auto and the restrictions that brings, would I be getting the most out of it.

 

[Nasher]

If you want optimal performance with ANY tune you do need to remove the first cat. It seems to be the main reason for the lack of torque below 4000 rpm.

 

[DereksDontRun]

and that's the dilemma... it's the same with many cars... But, what do you do? You know that removing it is technically a MOT fail, so that's step 1... But then what do you do with insurance? Either declare the mod and you've effectively admitted your car isn't road-worthy (non MOT compliant) or don't declare and back to arguments about uninsured due to fraudulent insurance statements...

 

[Nasher]

It's still road legal and emissions are within limits, insurers don't seem to bother.

It comes from an EU regulation about removing ANY emissions reducing device from a car I think, but no one actually cares as long as they can see a cat in place and readings are ok. In some European countries they will definitely pull you up on it though, if for some reason you go through their equivalent of the MOT.

 

[Lowe]

Dump the first cat. Seriously, it’s a night and day difference with a remap and I’ve never failed an MOT after losing mine.

As for intakes, you want one that follows the stock AFR as best as possible. Have a look on the FT86 forums, there’s a great series of threads which eventually lead to the Grimmspeed intake being developed. All the R&D, flow maps etc was shared for community approval, and it ended up being a pretty good bit of kit. Torqen sell them, and you can get discount if you message them via the Drivers Club forum.

 

[rebel rebel]

The Grimmspeed looks simular to the Takeda Momentum one.

 

[Delta3D]

and that's the dilemma... it's the same with many cars... But, what do you do? You know that removing it is technically a MOT fail, so that's step 1... But then what do you do with insurance? Either declare the mod and you've effectively admitted your car isn't road-worthy (non MOT compliant) or don't declare and back to arguments about uninsured due to fraudulent insurance statements...

Most the time just a declaration of "Aftermarket Exhaust" or "Aftermarket Manifold" will cover and Insurers wont mind as long as it's got an MOT on it.

Back to your point about the MX5, I've got an 86 and my dad's got a Mk3 MX5 (Mk1 Mx5 before that too).

I feel like they're both really fun cars. It doesn't bother me having a roof because even just with the 86 having the windows down is a really pleasant drive out on a summers day. Granted the 86 is a fair bit bigger than a 5, it still handles fairly similarly and remains planted thanks to the low center of gravity.