Upgrade advise needed

[neilp9876]

I bought henks car a few weeks ago, loving it but would like to carry on making improvements.

 

It's had a single decat (rear) and has a boost controller, but I don't think it's had a new fuel pump or intercooler. The bpu FAQ says the combination of boost and a remaining cat is not good as it can cause overheating issues.

 

What should be next to upgrade, the intercooler, pump or something else? (Not keen on removing the second cat because of mot issues)

 

What should I be looking at doing next?

[add heywood]

Single turbo

[Dnk]

Nos

[Homer]

What boost is it running now?

 

If you do the BPU mods it's best practive to remove the 1st cat and use a stock or (preferbly) a high flow 2nd cat. This will allow higher boost, safer.

 

Or, yuou could do what most do - remove both cats and just add the 2nd one back in when the MOT it due (or find a friendly tester )

 

To make the most of BPU is really needs at minimum a high flow 2nd cat.

 

A new fuel pump is a must for BPU from a safety aspect, I'd be surpirsed if Henk didn't do that already. IC is only worth changing if the current one is in poor condition.

[neilp9876]

The controller is set to 0.8 most of the time, the controller shows that peak boost on that setting can get up to 1.01. It has a higher second setting at 1.1 which shows a peak boost of 1.1.

 

Henk had the car dyno'd at 306 bhp but after reading more about bpu it seems it could be capable of more than that, so I was trying to find the area that was restricting it.

 

I guess the restriction is the first cat, and after reading the bpu faq it had me worried that using high boost without removing that cat wasnt a good idea. Probably fine on the road for short periods but I was hoping to do a track day which would be much more sustained stress on it.

[Mcgoo]

As Homer said, your pump may have already been uprated. It would be worth checking and if not getting a new one. There is a guide for changing the pump on here just have a read of that to see how to get to the pump. If it says Walbro or Bosch on it it has. Should only take about 15 - 20 mins. http://www.mkivsupra.net/vbb/showthread.php?t=45647&highlight=changing+fuel+pump

 

You then want to get that first cat off as it is very restrictive, the turbos will spin up much faster and as you said it will keep temps down at boost. If your j-spec you will need a restrictor ring between the two de-cat pipes also.

 

If you can't find a friendly MOT place then get yourself a second hand 2nd Cat (the rear one) and just put that on for the MOT. It will pass with just the one on and the rear one can be swapped out in about 20 mins.

 

Check the condition of your intercooler and replace if necessary.

 

If you are thinking of doing track days I would highly recommend fitting a couple of gauges so you can see what's going on. You already have a boost gauge by the sound of it. A wideband o2 (AFR) or EGT or both would be my recommendation.

Edited July 7, 2010 by Mcgoo (see edit history)

[Dnk]

If you go for a full decat you'll need a restrictor ring to keep the boost down and then you raise the boost with a controller which you already have.

 

If the cars not had the intercooler replaced then it will need changing, i took my my o/e smic off my car a few years ago and the core fins crumbled to dust.

Edited July 7, 2010 by Dnk (see edit history)

[neilp9876]

Will check the pump and intercooler as a matter of course, and then i'll look into removing the first cat but thats going to need more investigation from me. Probably a dumb question but does removing the cats make the exhaust any louder than it already is?

 

It has quite a few gauges already including fuel mixture and fuel pressure but to be honest I dont really know what the values are supposed to be.

 

I tried watching them last week and they seemed similar to those in this thread

http://www.mkivsupra.net/vbb/showthread.php?t=219406&highlight=lean

Didnt get accurate readings though as i went round a corner whilst watching the gauge and going flat out, I slowed down for a while after that [sHOCK][/sHOCK]

 

Thanks for the reponses though

[Mcgoo]

Probably a dumb question but does removing the cats make the exhaust any louder than it already is?

 

Yes it will but not a huge amount. When I put my cat back in for the mot, it surprises me how little difference there is. But it does depend on what exhaust you have fitted.