Pre cat? Or not?

[SeiW500]

I want to 'upgrade' the sound of my exhaust, car is a 93 4.3, question is it a pre-cat, the manifolds look to me like pre-cat???(http://www.actproducts.co.uk/product/ms01-griffith-pre-cat-manifolds/) and does this mean that there are NO cats in the system or just no pre-cats?
Was thinking either sleeved / part sleeved or full cherry bomb?
Is there anywhere near me Manchester that do sleeving?
Any idea how much it is to get sleeved?
Thanks, Andy

Edited by SeiW500 on Thursday 19th January 14:00

[Toma500]

Probably best doing this in stages , if yours is a 93 yr car it will have precats in the manifolds and a catted y piece .
Remove your y piece and youll see if its catted , if it is i would first remove the pre cats in the manifolds , this can be done in situ lots of threads on here on how to do , you will need a main cat in place for the mot for emissions unless you have a friendly mot man . I have left the main cat in mine for this reason . However plenty of cars post 92 are running cat free and get away with it. You will find running with no precats slightly noisier and a lot cooler running , complete decat noisier again and cooler and a bit more power . However if you run decatted you are recccomended to change a resistor in the wiring ,again itll be in a thread somewhere on here . Hope this helps , keep us informed of your progress a sound clip would be nice
Regards Tom

[SeiW500]

Hi Tom,

Having done a bit of looking around at removing pre-cats i'm really not sure that i have them???

If you look at the exhaust it looks very much like this http://www.actproducts.co.uk/product/ms01-griffith...

Thanks Andy

Edited by SeiW500 on Thursday 19th January 14:05

[davep]

SeiW500 said:

... Time to get searching!!

If the pic in your original post is of your car's engine bay then you'll probably not find any catalysers, pre- or otherwise.

In this context the term '92/'93 4.3 pre-cat is short form for '4.3 engine built prior to the catalytic converter requirement date'.

[SeiW500]

Hi Dave,

Yes i have come to that conclusion from my searching..... might look into getting silencer part sleeved.....

Thanks, Andy

davep said:

If the pic in your original post is of your car's engine bay then you'll probably not find any catalysers, pre- or otherwise.

In this context the term '92/'93 4.3 pre-cat is short form for '4.3 engine built prior to the catalytic converter requirement date'.

[andy43]

I think TVR preregistered some 4.0 and 4.3 cars in 1992 to get around the catalyst law - are you sure yours is registered as a '93? I thought (but stand to be corrected) that the only 1993 Griffs built for the UK market were the first 5 litre catted cars, unless this one is a Peter Wheeler special order? If it is a '93 it should have been catted from new.
If the manifolds are decent stainless then they'll be aftermarket ACT/JP - don't think JP ever made manifolds containing precats. Y piece could be catted or not, whether TVR or ACT/JP - is is flanged or V clamp? '92 no-cat cars were mostly 8 bolt flanged, then the catted 5 litres were V clamps and all catted, unless the cat's been knocked out. Only way to be 100% sure is to have a look.
Sleeving - if it's fully decatted AND fully sleeved it will wake the dead (and most car alarms). My 4.3 was sleeved and mentally loud. In a good way.
JP in Macc used to do modding work, not sure if they still do as they lost at least one of their custom fabricators, but other than a place in Bredbury next door to Darren Wood BMW I can't think of anywhere local.
4.3. The connoisseurs choice

[davep]

A quick check of the 14CUX tune resistor sleeve colour will indicate whether the engine is pre-cat (green) or cat (white). The resistor is part of the loom located in the passenger foot well above the battery, usually.

[SeiW500]

Car was first registered 01/09/1993, but was in Channel Islands , not sure if that makes a difference?
Neither the manifolds or Y piece are stainless, not sure I want to undo all the heat shield wrap that's on them just yet to harvest a poke around.
Will have a look in the morning to see if I can see any resistors and what colour they are, any idea on how big the resistor will be?
Would love to try a sleeved exhaust on the car befor butchering this one.........
I know Darren Wood BMW (Tis where I take my 335i for fetteling) so might pop round and have a chat to the fabricators next week, thanks for the tip.

[andy43]

Manifolds do look precat shaped - 4 pipes right up to the y piece connection. Actually - doh - there's no lambda sensors visible in your pic, unless they're hidden under the heat wrap or there's a single one lower down in the y piece for some weird reason, so you can probably assume you are cat free

Edited by andy43 on Friday 20th January 22:09

[RobXjcoupe]

andy43 said:

Manifolds do look precat shaped - 4 pipes right up to the y piece connection. Actually - doh - there's no lambda sensors visible in your pic, unless they're hidden under the heat wrap or there's a single one lower down in the y piece for some weird reason, so you can probably assume you are cat free

Edited by andy43 on Friday 20th January 22:09

Yep, check for lambda sensor in the manifolds. No lambda, no cat simples

[davep]

SeiW500 said:

... Will have a look in the morning to see if I can see any resistors and what colour they are, any idea on how big the resistor will be? ...

This pic shows the tune resistor (white in this example) bottom left.

[SeiW500]

Thanks, still not has a chance to check it out yet