BPU Question

[tayr]

Hi All

 

Planning on picking the Supra up next week and want to take it to BPU pretty quick.

 

It currently has the HKS Silent Hi Power and an HKS mushroom filter.

 

Am I best off buying the BPU sets of Whitbitz and asking them or SRD to fit the parts for me, or is there a better way to do it?

 

I don’t mind tackling work myself but last thing I want to do is overboost and cause an issue (no boost gauge or AFR on the cards yet. Or are these musts?)

 

Here to learn - thanks

 

JDM spec so I guess 1.2 bar for too long is not wise?

 

Edit: also going to Japfest tomorrow so if anyone there wants to share some advice it would be awesome

Edited May 4, 2019 by tayr (see edit history)

[rider]

If you do decat then you need the 1.2 bar restriction ring to ensure you don't over-boost the ceramic jspec turbos. Its easy enough done yourself and you can source parts cheaper that way than going full kit from one supplier. I'd recommend you keep both cats in your garage or bedroom somewhere as that always leaves the option to put it back to stock at a future date if that is what you or another owner wishes to do. I was never sure what has been done to my car as it ran over 330bhp when it was dyno run 12 years ago and it still has both cast and no on-board boost controller.

 

There are loads of threads on BPU upgrades

[mellonman]

as long as you get a restrictor ring then you should be fine , its a easy job to do your self worst bit will probably be getting the first cat bolts off

[tayr]

If you do decat then you need the 1.2 bar restriction ring to ensure you don't over-boost the ceramic jspec turbos. Its easy enough done yourself and you can source parts cheaper that way than going full kit from one supplier. I'd recommend you keep both cats in your garage or bedroom somewhere as that always leaves the option to put it back to stock at a future date if that is what you or another owner wishes to do. I was never sure what has been done to my car as it ran over 330bhp when it was dyno run 12 years ago and it still has both cast and no on-board boost controller.

 

There are loads of threads on BPU upgrades

 

as long as you get a restrictor ring then you should be fine , its a easy job to do your self worst bit will probably be getting the first cat bolts off

 

Thanks guys, Was just debating whether I should do it all, boost controller etc straight off the bat or whether to just take it easy

[mellonman]

I done all mine straight off the bat , but the stock side mount intercooler blew a end cap off so got a front mount soon after

[Dnk]

Just to be old and boring i'd be going over the car first to see if anything else needs attention

before upping the power it's got.

 

Service it, all fluids, check the brakes and get a full wheel alignment done is what i'd do first.

 

Then bin the HKS filter and fit OE airbox or an Apexi or K&N filter, what condition is the intercooler in, if its

original it could be falling apart, especially the fins, mine looked fine but the fins crumbled to dust when you

touched them. Also the rad, rad cap, thermostat would be in question unless they've been replaced. oh and the

dreaded heater matrix including all hoses

Edited May 5, 2019 by Dnk (see edit history)

[jonc]

I agree with DNK.

 

Get all the oily bits right first.

A few things that would be worth looking at now as BPU will show them after without doubt are.

 

Intercooler. Most original intercoolers are now toast and crumbling. No need for a FMIC as the SMIC are good for large BPU gains.

 

Turbos particularly JSPEC ceramics are more than likely shot by now and are worth checking first. With back pressure from the cats you may not see oil mist from the exhaust but you will when you go BPU. Most JSPEC turbos are coming to end of their life.

 

Brakes. Make sure all 4 corners are good to go. The calipers are known for seizing so a refurb of your calipers if original is not a bad thing. JSPEC brakes are fine btw although a lot of have upgraded.

 

Suspension. I would think any Sup on original suspension unless a late facelift will be having issues now or will do in a couple of years. A lot of the long term owners have gone for a rebuild.

 

Cooling. Make sure the cooling system is too notch and has been regularly serviced.

 

Belts. Have the drive belts and tensioners been changed use Mr T instructions? One to look at.

 

These girls are old now and a lot of worn parts need to be right when attempting BPU.

 

Mind as others have said because if the way the fuelling is controlled BPU is pretty basic on these. Most parts can be picked up from members on here particularly once they go single upgrade.

 

I have always ran with a restrictor ring without a controller but I guess a controller is better

 

Enjoy and good luck

[tayr]

@dnk @jonc

 

Thanks Guys - really appreciate the comments.

 

The car is being imported through Torque GT and alot of the stuff has been checked over - as per below photo.

 

I have also had the Engine Oil, Gearbox and Diff oil, cambelt, waterpump and spark plugs done aswell. (New tyres too) - i do plan to change the brakes for UK ones eventually.

 

I'll check the intercooler and radiator when it arrives - any recommendations of these if they need replacing? Ive heard mishimoto do good rads. If anything is shot it will be getting replaced. I am really hoping that the heater matrix is fine as i've heard that is a right PITA.

 

Interesting about the HKS filter - i always assumed the hks stuff was good, however i did just read that apparently people have found it only channels hot air from the engine so will look to replace that. Hopefully can find a stock airbox somewhere but they are rocking horse sherbert.

 

I'm not sure on the drive belts but according to Torque it looks in good condition. I guess with anything like this it's just a process of learning and trial and error.

 

Many thanks for the input guys

[nigelboyne]

Fisrt thing take the 1st cat out leave 2nd cat in for mot/nct emissions test you will only loose few hp and little bit response.2 upgrade the intercooler I went hks type r. 3 boost controller and fuel cut to raise the boost roughly 1.2 bar 17psi. That with the exhaust should give you 80to 100hp gain. Dyno graph mine

[Dnk]

HKS R type is way over the top for BPU, i went the same route and really wondered why i'd spent all that money

on an intercooler.

 

If i were doing it again i'd get a new SMIC which is already ducted unlike any FMIC you will fit.

 

Depending on your MOT man your car shouldn't pass the MOT without a cat fitted thus imo making

it a very grey insurance area

[Dnk]

I agree with DNK.

 

Get all the oily bits right first.

A few things that would be worth looking at now as BPU will show them after without doubt are.

 

Intercooler. Most original intercoolers are now toast and crumbling. No need for a FMIC as the SMIC are good for large BPU gains.

 

Turbos particularly JSPEC ceramics are more than likely shot by now and are worth checking first. With back pressure from the cats you may not see oil mist from the exhaust but you will when you go BPU. Most JSPEC turbos are coming to end of their life.

 

Brakes. Make sure all 4 corners are good to go. The calipers are known for seizing so a refurb of your calipers if original is not a bad thing. JSPEC brakes are fine btw although a lot of have upgraded.

 

Suspension. I would think any Sup on original suspension unless a late facelift will be having issues now or will do in a couple of years. A lot of the long term owners have gone for a rebuild.

 

Cooling. Make sure the cooling system is too notch and has been regularly serviced.

 

Belts. Have the drive belts and tensioners been changed use Mr T instructions? One to look at.

 

These girls are old now and a lot of worn parts need to be right when attempting BPU.

 

Mind as others have said because if the way the fuelling is controlled BPU is pretty basic on these. Most parts can be picked up from members on here particularly once they go single upgrade.

 

I have always ran with a restrictor ring without a controller but I guess a controller is better

 

Enjoy and good luck

 

Agreed

[Dnk]

The HKS filters are known for not filtering as well as Apexi and K&N

[Scooter]

I wouldn't even fit a boost controller, certainly initially fit the bpu parts and just adjust the restrictor ring until you see 1.1-1.15 bar (leaves some headroom for cold weather extra boost). The controllers can only increase boost so bar the ones that can regulate boost lower down the Rev range they just give you the option of increasing from the base/restrictor ring level.

 

What I am saying is you can have a nice powerful bpu car without any boost controller beyond a £10 restrictor ring, so for me that spend would come near the back of the list, it the icing on the cake if you like.

Edited May 6, 2019 by Scooter (see edit history)

[Dnk]

Once mine was set up i can't re call ever touching it again so the ring at 1.1 bar is the way to go cost wise

[Samurai 20V]

check all the vac hoses, VSV's, turbo link pipes, turbo condition before upping the boost.

 

Guarenteed those are shot, when you up the boost, they just go even faster or it shows the leaks..

 

I gained about 25wkw by fixing all this stuff.

[tayr]

check all the vac hoses, VSV's, turbo link pipes, turbo condition before upping the boost.

 

Guarenteed those are shot, when you up the boost, they just go even faster or it shows the leaks..

 

I gained about 25wkw by fixing all this stuff.

 

May seem like a stupid question but what is the best way to check the turbo condition

[nigelboyne]

HKS R type is way over the top for BPU, i went the same route and really wondered why i'd spent all that money

on an intercooler.

 

If i were doing it again i'd get a new SMIC which is already ducted unlike any FMIC you will fit.

 

Depending on your MOT man your car shouldn't pass the MOT without a cat fitted thus imo making

it a very grey insurance area

 

Supras will pass the emissions test with just 2nd cat in as long as the car is hot. The intercooler yes your correct overkill for bpu, but once bpu only matter time before single imo. Lots ways to go bpu it's all down to personal choice I guess.

[Dnk]

Yes each of us go their own way, the only reason i'd of gone single would have been if the OE twins

failed, to be honest these days for road use i don't see any point in having 600 + hp so a good new CW

or Whifbitz smic will still support that.

 

The emissions is only part of it now as the car has to have a cat fitted or its a straight fail

[tayr]

Yes each of us go their own way, the only reason i'd of gone single would have been if the OE twins

failed, to be honest these days for road use i don't see any point in having 600 + hp so a good new CW

or Whifbitz smic will still support that.

 

The emissions is only part of it now as the car has to have a cat fitted or its a straight fail

 

Thats interesting - i thought it was still only emissions based.. will more people just be doing a first decat only then? Leaving the second one in

[Dnk]

Thats interesting - i thought it was still only emissions based.. will more people just be doing a first decat only then? Leaving the second one in

 

No it changed not so long ago, from May last year i think. They also changed the rules on HID kits too

 

My UK spec used to pass the emissions without either cat fitted but would now

fail because the cats have been removed.

 

It's classed as a major fail too

Edited May 7, 2019 by Dnk (see edit history)

[Scooter]

Thats interesting - i thought it was still only emissions based.. will more people just be doing a first decat only then? Leaving the second one in

 

I think some either have a garage that doesn't know the Supra had one from new (or are 'friendly') or swap them in/out for the mot.

[Samurai 20V]

May seem like a stupid question but what is the best way to check the turbo condition

 

 

Boost gauge to check the boost levels is a start, but make sure no vac leaks.

 

Take the front turbo intake pipe out, check for damage to fins.

 

Smoking on idle when hot shows seals worn, although most times can be band aided with thicker oil.

[Pulley]

Take front inlet pipe off, grab nose of compressor wheel and wiggle, it shouldn’t have lots of side to side or thrust movement, also Check for oil on inlet and charge side of turbos

Hard to tell sometimes if you still have crank case breathing into the inlet

 

Dnk’s original advice is the best imo, and for intercooler to support 400ish bhp you don’t want bigger than 3” core really, and I’d stick with stock charge pipe size other wise you increase the charge side lag considerably with no gain as you’ll only ever need 400 levels of flow and cooling