Glanza_Mike Posted January 30, 2017 Share Posted January 30, 2017 Hi guys, Just a quick question about the 1st decat really. I know facelift and pre are different but what exactly was changed on the facelift model to require a different downpipe shape? The reason for the question is I've bought an American turbo kit. And then turbo kit is obviously made for the US spec Supra, so I need to use a UK spec decat, but I have a facelift Supra. And I'd just like to know before I splash out on a new one, if, in theory, in will fit. Thank you. Quote Link to comment Share on other sites More sharing options...
James Posted January 30, 2017 Share Posted January 30, 2017 I'm not sure about vs a U.K. decat, but I know that the flange angle on the VVTi decat vs pre-VVTi is different by a few degrees, meaning you would foul the gearbox casing if using the wrong one. Is it an aftermarket turbo kit and manifold you're going for? If so, you'd have to change your downpipe regardless? Quote Link to comment Share on other sites More sharing options...
j_jza80 Posted January 31, 2017 Share Posted January 31, 2017 As James said, the difference is between VVTi and non VVTi, NOT facelift and pre facelift. Facelift non vvti cars have the same first decat as pre facelift cars. But as you will be binning the first cat anyway (the turbo downpipe replaces it completely normally), it should just bolt up to any car regardless, as all second cat/decats are the same (IIRC). Also, don't be concerned if the downpipe needs a little fettling, it is quite normal, especially when using a turbo kit designed for LHD on a RHD car. Quote Link to comment Share on other sites More sharing options...
Glanza_Mike Posted January 31, 2017 Author Share Posted January 31, 2017 Ahh, play I didn't realise it was the vvti that made the difference not the pre/post facelift. Thanks chaps. So basically I've bought the PHR turbo kit, and it come with a short downpipe that bolts up to a UK/US spec first decat (because of the different flange). So I just wanted to make sure that if u buy a UK spec decat to swap for my current facelift decat, I wouldn't have any clearance issues if you know what I mean. Quote Link to comment Share on other sites More sharing options...
j_jza80 Posted January 31, 2017 Share Posted January 31, 2017 I've never heard of anyone fitting a UK spec cat pipe to a vvti, but I can't see why it would be an issue? Personally I'd bin that downpipe and get another that removes the first cat entirely, otherwise you have an extra, unnecessary join in the system. I would also recommend getting a flexi section welded in your second decat pipe, to take some strain/shock off the manifold Quote Link to comment Share on other sites More sharing options...
Glanza_Mike Posted January 31, 2017 Author Share Posted January 31, 2017 Thanks mate, i was just considering buying one of the TB developments UK Spec 1st decats, these have a flexi section already in them. This would be as good right? Quote Link to comment Share on other sites More sharing options...
j_jza80 Posted January 31, 2017 Share Posted January 31, 2017 I'd think so mate, probably best asking Tim for his thoughts. It probably wouldn't cost much more for him to make you a full, free flowing downpipe though... Quote Link to comment Share on other sites More sharing options...
Glanza_Mike Posted January 31, 2017 Author Share Posted January 31, 2017 Yeah possibly not mate, but there won't be any restrictions in this one? Will just be one extra connection like you said, the PHR downpipe looks pretty decent tbf. Quote Link to comment Share on other sites More sharing options...
j_jza80 Posted January 31, 2017 Share Posted January 31, 2017 No physical restrictions No, but you chant best a straight price of pipe with no joins for flow Quote Link to comment Share on other sites More sharing options...
Glanza_Mike Posted January 31, 2017 Author Share Posted January 31, 2017 This is true It does cause a reasonably large problem and potential cost though. As i'd have to fit the turbo kit and then get the car towed the 1 hour or more to Tim as it'd be undriveable at that point to make the downpipe. Quote Link to comment Share on other sites More sharing options...
Glanza_Mike Posted February 1, 2017 Author Share Posted February 1, 2017 Actually, thinking about it, if Tim makes these decays fresh would it best for me to get a vvti decat made up just with a UK spec flange on? Quote Link to comment Share on other sites More sharing options...
Frank Bullitt Posted February 1, 2017 Share Posted February 1, 2017 Why don't you want to use a down pipe and mid pipe? You seem to be making this a lot more complicated than it needs to be Quote Link to comment Share on other sites More sharing options...
Glanza_Mike Posted February 1, 2017 Author Share Posted February 1, 2017 What do you mean mate? I will be doing this essentially. The PHR turbo kit come with a short downpipe, that bolts straight up to a UK spec downpipe/1st decat. And then it's all just standard from there. I just want to make sure the UK spec decat will align properly in my vvti car. Quote Link to comment Share on other sites More sharing options...
Rob W Posted February 1, 2017 Share Posted February 1, 2017 I'm guessing you have bought the PHR street kit with cast manifold? Which uses the shorter downpipe that is designed for that set-up. I don't see why you'll have any issue as the only reason for the difference flange angles on the decats is to do with the downpipe of the stock manifold between UK/Non-VVTI and VVTI. As your changing all that anyway you have no issue. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted February 1, 2017 Share Posted February 1, 2017 Has anyone run this kit on a RHD car? My first concern would be getting stuff past the steering column. Quote Link to comment Share on other sites More sharing options...
Glanza_Mike Posted February 1, 2017 Author Share Posted February 1, 2017 I'm guessing you have bought the PHR street kit with cast manifold? Which uses the shorter downpipe that is designed for that set-up. I don't see why you'll have any issue as the only reason for the difference flange angles on the decats is to do with the downpipe of the stock manifold between UK/Non-VVTI and VVTI. As your changing all that anyway you have no issue. You are correct mate, got the cast manifold setup with the shorter downpipe. I was under the impression that all the turbos and manifold etc were the same for vvti and non but eh downpipe was different to clear the gearbox or something like that? So wouldn't that still be the case when changing turbo? Has anyone run this kit on a RHD car? My first concern would be getting stuff past the steering column. Yes Chris, Berg has it fitted on his car, he has a non-vvti though and used a UK spec downpipe and it fit perfectly. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted February 1, 2017 Share Posted February 1, 2017 OK, let's assume you had a UK / USA spec engine and a VVTi J-Spec engine. The 1st cat differences are the flange size and the angle of the flange, both determined by the adaptor after the exhaust control valve casting. There are only effectively three different TT 1st cats. UK /USA, none VVTi J-Spec and VVTi J-spec. Does that help? I think, if I am following this right, you need a UK spec downpipe as any VVTi specific stuff above that is now gone? Quote Link to comment Share on other sites More sharing options...
Glanza_Mike Posted February 1, 2017 Author Share Posted February 1, 2017 Hey Chris, any specific VVTI stuff is indeed now gone. I thought the angle of the flange and downpipe were different to miss something that was different on the vvti engines though? (something not turbo or manifold related) or is this not the case? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted February 1, 2017 Share Posted February 1, 2017 Not as far as I have ever noticed, no. Quote Link to comment Share on other sites More sharing options...
Glanza_Mike Posted February 1, 2017 Author Share Posted February 1, 2017 Okay Chris well I've trusted you and gone with the UK spec decat! let's hope you're right! thank you. Quote Link to comment Share on other sites More sharing options...
Frank Bullitt Posted February 1, 2017 Share Posted February 1, 2017 What do you mean mate? I will be doing this essentially. The PHR turbo kit come with a short downpipe, that bolts straight up to a UK spec downpipe/1st decat. And then it's all just standard from there. I just want to make sure the UK spec decat will align properly in my vvti car. Ignore me, I know nothing. I shouldn't be posting past my bedtime Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted February 1, 2017 Share Posted February 1, 2017 Okay Chris well I've trusted you and gone with the UK spec decat! let's hope you're right! thank you. Now steady on old boy, I am not even 100% sure of what you are trying to do Quote Link to comment Share on other sites More sharing options...
Glanza_Mike Posted February 1, 2017 Author Share Posted February 1, 2017 Well it's too late now lol And i'm not sure either way to be honest. You and Rob W both seem to think a standard UK spec would be best so that will do for me. Quote Link to comment Share on other sites More sharing options...
Rob W Posted February 1, 2017 Share Posted February 1, 2017 Well it's too late now lol And i'm not sure either way to be honest. You and Rob W both seem to think a standard UK spec would be best so that will do for me. It will be fine mate, the different flange angles are nothing to do with running past the gearbox or subframe parts. Purely down to the design of the stock manifold downpipe. Quote Link to comment Share on other sites More sharing options...
Glanza_Mike Posted February 1, 2017 Author Share Posted February 1, 2017 I hope you're right mate Quote Link to comment Share on other sites More sharing options...
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