T-I-G-G-E-R Posted March 24, 2009 Share Posted March 24, 2009 Hi Guys and Girls:) Just need some advice ,what are your thoughts of fitting this after market manifold to my jspec 1996 Supra n/a. It's made by a company called OBX and it look's as if a decat down pipe is included in the price:) What sort of power gains am I likely to expect on a stock n/a other than a straight through Motoria big bore exhaust system fitted. And what's the current situation on passing the DREADED MOT with this fitted. Has any n/a owner's out there fitted one or recommend another make. Cheers Carl:) Quote Link to comment Share on other sites More sharing options...
supspower Posted March 24, 2009 Share Posted March 24, 2009 Looks like a nice bit of kit. Also looks like it gets rid of both cats 1st and 2nd so for MOTs with this on it will fail in theory cant see a way having this and keeping any cats. Usual bhp gains on manifolds are 10-15 i believe but with the decats as well some people would say 20bhp but whether you will actually gain that is another question. Will make you exhaust sound LOUD!!!!!!!!!!!!!!!!!!!!!!! Quote Link to comment Share on other sites More sharing options...
Al Massey Posted March 24, 2009 Share Posted March 24, 2009 I have an autobahn88 manifold fitted with both decats removed. It feels alot better to drive. It only passed an mot due to them doing me a favour But i have had the supe pass an mot easily with just one cat fitted Quote Link to comment Share on other sites More sharing options...
jim_supra Posted March 24, 2009 Share Posted March 24, 2009 Never seen that one before, looks good. You may well have issues with clearance on the steering column when trying to fit it as It'll be made for a left hand drive supra. Quote Link to comment Share on other sites More sharing options...
Supra-Brett Posted March 24, 2009 Share Posted March 24, 2009 Looks like a nice bit of kit. Also looks like it gets rid of both cats 1st and 2nd so for MOTs with this on it will fail in theory cant see a way having this and keeping any cats. QUOTE] Im not so sure on this. Its almost impossible for my 1993 N/A to fail the MOT on emmissions. The DVLA dont have emissions data for the N/A (well not for a 1993 anyway) and hence the MOT inspector sets the CO levels to 3.5% (normally is about 0.1% or so for most cars from memory). Basically this means the engine can have no cats, run like a bag of crap and have loads of mods etc without being anywhere near failing. Well thats my experience anyway. Maybe the DVLA have emmissions data for a 1996 N/A but i doubt it as the N/A was never a UK car (jap only) You shouldnt have any probs fella. As for power, ive not yet seen anyone on here do a before and after dyno plot for such mods on an N/A but i here 10BHP all the time. Hope that helps Quote Link to comment Share on other sites More sharing options...
T-I-G-G-E-R Posted March 24, 2009 Author Share Posted March 24, 2009 Hi thank's for your help do you mean this one mate autobahn88 exhaust system Toyota Supra JZA80 3.0L N/A The exhaust manifold is very rare to find. It gives u high performance when your motor is over 4000rpm. It delivers outstanding performance versus stock castled manifold. Proven 15+ horse power gain. The Stainless Steel uprated Supra NA manifold replaces stock manifold as well as 1st DECAT. Give u instant horse power after 3000rpm. I really don't like the sound of loosing both Cats but this leave's one for the MOT:) PS any fitting issue's with this one Cheer's Carl Quote Link to comment Share on other sites More sharing options...
Kirk Posted March 24, 2009 Share Posted March 24, 2009 (edited) 10- 15 hp is most common gain but with a full decat from my understanding you will loose low end power as NA's rely on having some backpressure. Edited March 24, 2009 by Kirk (see edit history) Quote Link to comment Share on other sites More sharing options...
Gaz6002 Posted March 24, 2009 Share Posted March 24, 2009 10- 15 hp is most common gain but with a full decat from my understanding you will loose low end power as NA's rely on having some backpressure. Has anyone actually dyno-tested before and after fitting a manifold? Because those figures sound remarkably like MHP to me (marketing horse power). Also, I doubt you'll lose anything low down. Backpressure shouldn't be an issue. Quote Link to comment Share on other sites More sharing options...
Al Massey Posted March 24, 2009 Share Posted March 24, 2009 Hi thank's for your help do you mean this one mate http://i197.photobucket.com/albums/aa233/purplelava_2007/17cf_2_41.jpg autobahn88 exhaust system Toyota Supra JZA80 3.0L N/A Cheer's Carl Yep thats the badger. The only drama i had when fitting was that i needed to file out one of the wholes a little for it to fit on snug, which only took me 10 mins, the rest was easy. With ref to gains, i can honestly say hand on heart that low down torque is unbelievable. Pulling away is so much better and the noise is pretty loud. My middle pipe is 2.5 inch decat and since fitting the whole exhaust setup i have noticed top end isnt as high as it used to be but low down and mid range is miles better. Quote Link to comment Share on other sites More sharing options...
Dan8 Posted March 24, 2009 Share Posted March 24, 2009 i got that o b manifold fitted but only after major modifications to it The 02 sensors need relocating & screw type sensors installing otherwise they hit the bulkhead & the flanges are not true at base of manifold & felt faster when standard was fitted as you loose the 4800 r p m kick when you change manifold for some reason & d a z z i had the other manifold pictured & that would not fit either Quote Link to comment Share on other sites More sharing options...
Aldo87 Posted March 24, 2009 Share Posted March 24, 2009 have a look http://www.mkivsupra.net/vbb/showthread.php?t=164925 Quote Link to comment Share on other sites More sharing options...
Nic Posted March 25, 2009 Share Posted March 25, 2009 Has anyone actually dyno-tested before and after fitting a manifold? Yes I had Loks car dynoed before and after fitting one of the manifolds I make. It was a bit inconclusive though as the car was down on power to start with for some reason. The manifold increased the power by 8hp, if it had been running right it possibly would have made a bit more. Quote Link to comment Share on other sites More sharing options...
mitulparmar787 Posted March 25, 2009 Share Posted March 25, 2009 A similar OBX manifold has been fitted to quite a few GS300's in the US - http://www.clublexus.com/forums has more information about these along with a few dyno graphs floating around as well. They were pretty well regarded for the money last I remember. Quote Link to comment Share on other sites More sharing options...
Dan8 Posted March 25, 2009 Share Posted March 25, 2009 i might sell my modified 1 & go to standard if interested Quote Link to comment Share on other sites More sharing options...
Ian C Posted March 26, 2009 Share Posted March 26, 2009 NA's rely on having some backpressure. You're thinking of exhaust pulse tuning. Backpressure is a bad thing as it causes intake charge contamination. Exhaust pulse tuning helps scavenge the cylinders of exhaust gas and suck in a fresh intake charge - this is where most of the power gain from NA headers comes from, and it'll only be in part of the rev range as you can only tune to a relatively narrow rev band. A car can feel sluggish suddenly by fitting a performance exhaust manifold because the OEM tuning tends to be in the 2500 to 4000rpm range for everyday drivability, but the performance one shifts this right up there out of the normal driving region, so you lose power for most of your driving time. You can get a gain across the board for lowering the restrictions of a stock log-style cast manifold though, which can offset this to a point. Depends on what the stock one is like and if the replacement is actually better. Horses for courses, you'd have to do a before-and-after dyno to see what the result is, there is no way of working it out beforehand. -Ian Quote Link to comment Share on other sites More sharing options...
Dave Posted March 26, 2009 Share Posted March 26, 2009 i have both cats out and nick is probably more accurate with 8-10 bhp gain it probably be more with one of NICS manifolds, but it does feel more responsive. my mot guy says its only pre 92 cars that dont need an emissions test Quote Link to comment Share on other sites More sharing options...
Dan8 Posted March 28, 2009 Share Posted March 28, 2009 what about a w h i f b t z decat are they alright Quote Link to comment Share on other sites More sharing options...
Dazzi Posted March 28, 2009 Share Posted March 28, 2009 I bought 2 autobahn manifolds... both crap. I gave up in the end and sold them on to someone that was prepaired to 'heavily mod' them to fit. Quote Link to comment Share on other sites More sharing options...
T-I-G-G-E-R Posted March 29, 2009 Author Share Posted March 29, 2009 I'm now very confused lol but thanks for all your advice think i'll be sticking to the standard manifolds for now but looking into getting a a decat pipe made up Cheers Carl Quote Link to comment Share on other sites More sharing options...
supradriver Posted March 29, 2009 Share Posted March 29, 2009 that looks well nice Quote Link to comment Share on other sites More sharing options...
T-I-G-G-E-R Posted April 8, 2009 Author Share Posted April 8, 2009 So Guy's to come to some positive conclusion does anyone know what if any aftermarket manifold will fit. Cheer's Carl Quote Link to comment Share on other sites More sharing options...
Dazzi Posted April 9, 2009 Share Posted April 9, 2009 TBH mate it's hit and miss. I read a guys post on the Aussie forum about him using the stock headers and boring them out and fitting a decat pipe like CW and Whifbitz sell. Might be worth a go seeing as there are a few stock headers kicking around and it doesn't matter if you mess it up in the process as you can source more. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.