Decat manifold

vatovey · February 5, 2010, 23:21

Evening all,

Thinking about decatting my MR2 in a few months, probably with a new cat free manifold.

I've found one on eBay, could you advise if this is decent - or a pile of poo, or whether there are better options available for a similar price.

m http://cgi.ebay.co.uk/Toyota-MR2-Roadst ... 518fcfc905 m

Cheers, Vaughn.

uktotty · February 6, 2010, 00:54

Looks cheap! How much is a Che Manifold?

E · February 6, 2010, 03:12

Not sure about that one mate but this is the one I bought and have been using for the last two years with no problems, I believe that it is a Che manifold.
m http://cgi.ebay.co.uk/00-07-Toyota-MR2- ... 5885d6fbe2 m

E · February 6, 2010, 03:19

Forgot to add if you go for this one, do not use the Head to manifold gasket that they supply as it is rubbish and will probably leak after a short time the original is excellent and should be perfectly re usable.

Anonymous · February 6, 2010, 08:00

We fitted on of these without trouble using the original gasket as mentioned.
James

vatovey · February 6, 2010, 09:44

apologies for the dippy question, I notice on the ebay advert 'E' posted it says the manifold is for the later MR2 version, whereas mine is the earlier version made in 2000 - will it still fit ok ?

E · February 6, 2010, 11:34

Yes it fits any Roadster 00 - 07 they are all the same manifold. s:)

s:)

uktotty · February 6, 2010, 12:48

The MR2 Roadster is the latest MR2 Version, its the MKIII, before that was the MKII and the MKI s;)

s;)

stargazer30 · February 6, 2010, 16:28

Quote from: "E"Not sure about that one mate but this is the one I bought and have been using for the last two years with no problems, I believe that it is a Che manifold.
m http://cgi.ebay.co.uk/00-07-Toyota-MR2- ... 5885d6fbe2 m

Guys, does this manifold need to be wrapped or does the stock heat shield still fit over it. Also does the o2 sensor throw up a code due to there being no catalyst?

If yes to the above I'd be better off getting a 2nd hand stock manifold thats been gutted already?

David

mrzwei · February 6, 2010, 16:55

If it is a Che then it will have all of the attachments required for the stock heatshields. Some choose to run without them and some may well choose to use wrap. Mine didn't throw a cell and I don't remember others having reported any problems. The main cat gets it through the mot.

vatovey · February 6, 2010, 22:03

sorry - I meant pre and post facelift.

Anyways, I have purchased the one 'E' suggested, will fit it after my MOT in March when the weather gets a bit warmer.

andywood · February 7, 2010, 20:05

Why not just gut the pre-cats from your existing manifold and have very little or no cost?

Andy.

mrzwei · February 7, 2010, 20:31

If the only issue is cost, then you are right. The results from one of the dyno days also showed a bhp gain from the che, plus it is lighter.

vatovey · February 8, 2010, 09:13

I thought about simply gutting the existing manifold, but if something does go pearshaped afterwards in terms of emissions then I would need to get hold of a new set of pre-cats, or a new stock manifold with pre-cats included, which would cost ALOT more than £130 I think.

This way, after installation of new Che manifold, if everything is ok - I can sell my stock manifold with pre-cats included, and if I'm lucky - it may cover the expense of the Che manifold.

Anonymous · February 8, 2010, 09:28

No chance - you will be lucky to give it away.

The pre-cats have no real use in this country except to destroy your engine, it's only in America where they are required for cold start.

Using a stock de-catted manifold brings issues with it as well, not the best gas flow and therefore can bring problems.

Rob.

vatovey · February 8, 2010, 12:18

k, didn't realise they were worth little to nothing s:(

s:(

Nevermind, I guess I'll keep it just incase I need/want to take the car back to stock.

andywood · February 9, 2010, 20:25

Quote from: "FGRob"Using a stock de-catted manifold brings issues with it as well, not the best gas flow and therefore can bring problems.

Rob.

What issues are those Rob?? I was not aware of any known problems people have encountered - did i miss something?

Andy

DannyN · February 9, 2010, 20:33

Quote from: "andywood"What issues are those Rob?? I was not aware of any known problems people have encountered - did i miss something?
Andy

Andy its just the fact that you've made 2 large vacuous areas for your exhaust gases to bounce around in instead of exiting straight out

Anonymous · February 9, 2010, 20:44

Mine runs sweet.

diddy · February 9, 2010, 21:15

what are the benifits from the stock manifold with pre cats gutted to the che manifold i really cant see and difference between the 2 apart from the che maybe lighter but is it really worth it?

mrzwei · February 9, 2010, 23:05

A dyno day on here a couple of years ago showed a definate bhp / torque improvement with the che manifold over the stock. also, as you say, it is lighter and it looks better. This sort of tuning is always going to be incremental and there are even better manifolds out there which others have used. It can be a pain in the arse swapping because the nuts and bolts will have a degree of corosion so you have to prepare for that with something like plusgas. The gasket supplied with the kit is not good so you have to use the oe part. If you search something like 'che manifold' then there is a moutain of info on here about this mod. Nobody has had any problems with just removing the precats from the stock manifold and there is a very informative thread, probably by Mark, on how to do this. This involves taking the manifold off of the car so the same 'sods law' issues arise. If I recall correctly, a couple of people have had the precats removed with the manifold in situ.

t-bone · February 10, 2010, 04:11

Quote from: "stargazer30"
Quote from: "E"Not sure about that one mate but this is the one I bought and have been using for the last two years with no problems, I believe that it is a Che manifold.
m http://cgi.ebay.co.uk/00-07-Toyota-MR2- ... 5885d6fbe2 m

Guys, does this manifold need to be wrapped or does the stock heat shield still fit over it. Also does the o2 sensor throw up a code due to there being no catalyst?

If yes to the above I'd be better off getting a 2nd hand stock manifold thats been gutted already?

David

IMO you never want to wrap a header. you will get a very temporary heat containment that will feel great BUT the metal in the manifold will overheat weaken and ultimately the metal will fatigue such that the wrapping is the only thing holding it together. You are much better off spend a little money for getting the header coated. wrapping is bad regarding manifolds and if you read the fine print of the wraps they say it is intended for other applications such as keeping intakes cool etc....

diddy · February 10, 2010, 08:47

its exacly how i done my pre cats manifold stayed on i just remove the 2 lambda sensors, took the cat of underneath and used a very large screwdriver job done.

Anonymous · February 12, 2010, 13:38

I got one off ebay for 80 usd (black ceramic coating) and works well, e.g. works as a header s:)

s:)

No need to buy 300-400 usd headers in my opinion.

Anonymous · February 12, 2010, 15:13

Quote from: "Muniek"I got one off ebay for 80 usd (black ceramic coating) and works well, e.g. works as a header s:) s:)

No need to buy 300-400 usd headers in my opinion.

No it's more like 300 - 400 GBP and yes there is a need if you want better performance. s:wink: :wink: s:wink:

Decat manifold

uktotty

uktotty