90 Exhaust Upgrade

[CAT]

I just have a few questions arising from some scanning of the net recently. I would like to get a 2.5 inch exhaust upgrade, (would a 3" be more beneficial?) but there are some questions I need answering. My 90 will have to be DOE'd (Department of the Environment) like the MOT where they will do the usual checks and they will assess emissions, so I feel I need a catalytic convertor to cut down on my emissions. Do most of the custom exhausts ditch this element as it causes restrictions on gas expulsion?
Also does the turbo on the 90 1KZ TE need a bigger dump pipe? I have read about this on other forums for the surf/hilux as it seems a really good mod, if a bit difficult to achieve.
Is the main reason for a side exhaust so that there is less distance for the gases to travel through a restrictive pipe before they are expelled? In comparison to an exhaust travelling to the rear of the vehicle.
I would like a custom exhaust but I am wondering if I can make it practical, i.e will I achieve enough gain from what I put into the mod? I use my 90 for fishing trips, some light off roading and doing some towing/general pulling around the place. It spends 80% of its time on the road and I really just want to increase the engine performance for economical reasons and also because I love working on my 90. I will not be using it as a purpose built off road vehicle so want to keep her practical. Hope you guys can help. Liam.

 

[clivehorridge]

Economy seems high on the list. You don't mention stainless, but if you intend to keep the car a number of years, I'd recommend it. I understand the 4.2 80 turbo benefits from being 3" but otherwise I dunno.

Plenty on here will. Good luck.

 

[Shayne]

I'm planning to get a 3" stainless fro Prospeed in Cardiff , i think 2.5 is standard diameter for most of the factory pipe . Search the forum for Lil' Blue (thats the name of a well known truck on here) Lil' Blue has a 3" straight through exhaust and as far as i'm aware there's been no problems with M.O.T .

 

[Chris]

Lil Blues does NOT have a 3" system. It's mostly 2.5 with some sections of 2.25. Never had an issue with MOT whilst I had it, but then it's a diesel! Not really an issue for MOT other than noise. OK I did have some comments, mostly Ooh that sounds great. But on an oil burner the exhaust doesn't make any difference to emissions. They're just baffles in tin boxes. There's no CAT in there. Going to 3" is pointless unless you do the down pipe too. Your exhaust is only as big as the smallest section which as at the exit of the manifold. You need a Beau Desert or something similar. That's where the gain is, not just in making the rest of the tube bigger.

 

[CAT]

Thanks guys. Yes I have followed Lil blues journey to date and its an inspirational 90!

So no cat on the diesel then? That's just for a petrol? Ok, another question answered.

So Chris how did you form the infamous dump pipe? Did you make from scratch? I'll search the forum for a link if you have a thread on it. I have read that it seems to be one of the most beneficial mods. Excuse my ignorance but Beau Desert? Explanation please!

So lil blue had a straight through exhaust? I was thinking of getting a muffler just to tone it down a bit, shouldn't have a drastic effect should it?

And finally the advantage of a side exhaust over a rear one is just quicker expulsion of gases then yes?
Thanks in advance guys. Liam.

 

[Shayne]

Still have a look at prospeed , i phoned him up and he basically told me what i want , though he said he would have to take a look at the truck first . They don't just make exhausts to fit certain vehicles they make it to fit your car specifically so no two are identical . They also make stainless baffles and their website has a few videos so you can choose how you want the zorst to sound !

 

[Chris]

I didn't make the dump pipe. That's why the system wasn't 3"!
Coming out of the side is cosmetic. Don't get too carried away with the benefits of this mod. Getting rid of the boxes sheds weight and removes snags under the vehicle for off roading
The turbo does spool up a little better but it's not like adding an inter cooler or something.

Beau Desert make dump pipes in 3"
If you are serious about increasing performance then you need increase the bore of the system right through. Pro speed might take the header off and do a job on it. I don't know.
LB was mostly done for weight and clearance

 

[CAT]

Thanks again, Plenty of food for thought there.

 

[Shayne]

Hear Lil' Blue growl here http://www.landcruiserclub.net/forums/showthread.php/49195-Lincomb-September-7th-8th/page16?highlight=lincomb

This thread may also interest you .



[url]http://www.landcruiserclub.net/forums/showthread.php/49574-Elecronic-Diesel-Tuning-Devices?highlight=digital+tuning+devices
[/URL]

 

[wobbly]

You will see a real difference if you can add an intercooler, maybe off a Prado.

Increasing the stock dump pipe to 3" will enable the heat to get shifted out quicker, always a good idea if generating more heat.

Pete