CAT SIZE?

NCCMUR · Post by **NCCMUR** » Sun Mar 18, 2012 6:38 pm

alright fellow lg'ers

a wee question regarding my exhaust.i currently have what i believe is an e-gay stainless system :usual 4 branch mani, the downpipe is jdm size (its longer than oem uk) the cat then mid section,its flanged at the cat but the backbox is sleeved over the top of midsection.I dont know if the flange has been removed from either the backbox or mid-section.

now i have OEM manifold and downpipe but the key question is the cat for uk and jdm different in length??
the mid-section should be slightly longer to make up for the shorter downpipe and the backbox should be a standard size lengthwise

cheers in advance

bristol_bb4 · Post by **bristol_bb4** » Sun Mar 18, 2012 6:49 pm

you've got it wrong mate

manifold/downpipes are identical

ukdm cat is longer - catback is shorter
jdm cat is shorter - catback is longer

as for the backbox question, as standard the whole system is flanged, companies like longlife and powerflow use sleeve joints for ease of manufacture, in reality they are crap

NCCMUR · Post by **NCCMUR** » Sun Mar 18, 2012 7:16 pm

bristol_bb4 wrote:you've got it wrong mate

manifold/downpipes are identical

this may be true for OEM either uk or jap but trust me its shorter than the one currently on my car i know this for a fact through bitter experience

does anyone know the actual length of the uk or jap cat so i can measure mine and get the correct catback pieces?

what im assuming is its the cat original to the car and previous owner has got e-bay system and chopped catback to suit if you know what i mean.

bristol_bb4 · Post by **bristol_bb4** » Sun Mar 18, 2012 7:32 pm

really??! thats weird ive done a few now and they have all been exactly the same

just noticed your 5th gen

all 4ths are the same, just copied this from PUK for you

97 spec and 99 spec Preludes have completely different exhaust systems. Quite obviously due to the engine change from the A5 to the A8.

Although overall from start to finish the system is the same length, all the components like A Pipe, Cat, B Pipe are different.

Honda EPC has shown this:

97 Spec 2.2 VTi:
Downpipe (A-Pipe) #18210-S30-931
Cat Pipe (Comp Converter) #18160-P5M-G00
Centre Section (B-Pipe) #18220-S30-A32

99 Spec 2.2 VTi:
Downpipe (A-Pipe) #18210-S30-E31
Cat Pipe (Comp Converter) #18160-P5P-G10
Centre Section (B-Pipe) #18220-S30-E21

So buyers beware, lengths are not the same! It fair to say that all aftermarket exhaust products will be made to 97 spec fitments, so if you have a 99 spec lude, then prepare to either do some custom work to make ends meet, or buy a complete 97 spec system from A-Pipe through to the Exhaust Tip to ensure a correct fit on all sections.

Manifolds/downpipes will be too short, De-Cats will be too short, and cat back exhausts will be too long for a 99 spec.

So what i intend to do now, is, keep my 97 spec manifold/downpipe, keep the 97 spec de-cat and buy a 97 spec cat back system. So my entire system will be converted to 97 spec fitments and wont have to do any custom work extending/cutting pipes to meet joins.

NCCMUR · Post by **NCCMUR** » Sun Mar 18, 2012 8:07 pm

thanks for that mate

i knew the 97 and 99 were different sizes wasnt so sure about the cat though so as i said iv got OEM manifold,OEM downpipe, ithink OEM cat, so i need OEM midsection and backbox although i quite fancy one of those backboxes with the massive tailpipe cant remember the manufacturer

**edit** like the one on mills car