VR6Will 0 Posted July 10, 2006 Report Share Posted July 10, 2006 from a mk3 syncrohas anyone fitted one of these to their 2.8 obd2? what gains if any are to be had? Link to post Share on other sites
RIX 0 Posted July 11, 2006 Report Share Posted July 11, 2006 all obd 2 are the same,so no gains unless u start port and polish. Link to post Share on other sites
mk3anni 0 Posted July 11, 2006 Report Share Posted July 11, 2006 all obd 2 are the same' date='so no gains unless u start port and polish.[/quote']WRONGThe 2.9 inlets have a bigger chamber, so are able to shift more air.You might see a small gain. Link to post Share on other sites
Eat this 2 Posted July 11, 2006 Report Share Posted July 11, 2006 all obd 2 are the same' date='so no gains unless u start port and polish.[/quote']WRONGThe 2.9 inlets have a bigger chamber, so are able to shift more air.You might see a small gain.yes they open up pretty much straight after the tb whereas 2.8 r t shaped trn it over and ul see what we meani assume it flows more air better high up the rev range with a possible slight reduction in torque at low revs (countered by the extra cc on 2.9) Link to post Share on other sites
gav_113 0 Posted July 11, 2006 Report Share Posted July 11, 2006 ive opened up my std manifold, to c if it makes any difference, just need to weld it up now! Link to post Share on other sites
VR6Will 0 Posted July 11, 2006 Author Report Share Posted July 11, 2006 exactly what the sort of info im after gav_vr6 let me know how you've got on once its done, affects on bhp, driveability etc etc Link to post Share on other sites
gav_113 0 Posted July 12, 2006 Report Share Posted July 12, 2006 ok i will post results, hopefully should have it done next week, if i can find time! Link to post Share on other sites
RIX 0 Posted July 12, 2006 Report Share Posted July 12, 2006 where not talking obd1 here but obd2 and they alle the sameobd1 theres a big diff. but thats another tread Link to post Share on other sites
FishWick 21 Posted July 13, 2006 Report Share Posted July 13, 2006 I've got the 2.8 OBD2 manifold and throttle on my 2.9 engine and it pulls a lot better than it does with the 2.9 manifold.The CC difference between the 2.8 and 2.9 means nothing, purely a marketing excercise to seperate the Corrado from the Golf.....the differences in power and delivery are purely managment and intake governed. 2.9 lets more air in, but at the expense of bottom end. 2.9 has a higher rev limit, it was the fastest production VW at the time, so they didn't care about bottom end, just so long as it could pull 145mph.OBD2 2.8s are by far the best daily usable VR6 engine. Link to post Share on other sites
Eat this 2 Posted July 13, 2006 Report Share Posted July 13, 2006 whats the rev limit on a 2.9? Link to post Share on other sites
VR6Will 0 Posted July 13, 2006 Author Report Share Posted July 13, 2006 where not talking obd1 here but obd2 and they alle the sameobd1 theres a big diff. but thats another treadWrong as someone has already pointed out to you! You can get a 2.9 obd2 manifold! they came on the mk3 vr6 syncro Link to post Share on other sites
VR6Will 0 Posted July 13, 2006 Author Report Share Posted July 13, 2006 I've got the 2.8 OBD2 manifold and throttle on my 2.9 engine and it pulls a lot better than it does with the 2.9 manifold.The CC difference between the 2.8 and 2.9 means nothing' date=' purely a marketing excercise to seperate the Corrado from the Golf.....the differences in power and delivery are purely managment and intake governed. 2.9 lets more air in, but at the expense of bottom end. 2.9 has a higher rev limit, it was the fastest production VW at the time, so they didn't care about bottom end, just so long as it could pull 145mph.OBD2 2.8s are by far the best daily usable VR6 engine.[/quote']so you have had at one point a 2.9 obd2 manifold on your car then went back to a 2.8 obd2 manifold? Link to post Share on other sites
Eat this 2 Posted July 13, 2006 Report Share Posted July 13, 2006 I've got the 2.8 OBD2 manifold and throttle on my 2.9 engine and it pulls a lot better than it does with the 2.9 manifold.The CC difference between the 2.8 and 2.9 means nothing' date=' purely a marketing excercise to seperate the Corrado from the Golf.....the differences in power and delivery are purely managment and intake governed. 2.9 lets more air in, but at the expense of bottom end. 2.9 has a higher rev limit, it was the fastest production VW at the time, so they didn't care about bottom end, just so long as it could pull 145mph.OBD2 2.8s are by far the best daily usable VR6 engine.[/quote']so you have had at one point a 2.9 obd2 manifold on your car then went back to a 2.8 obd2 manifold?no iirc he converted from obd1 to obd2 that included the obd2 tb and inlet mani (which is 2.8) Link to post Share on other sites
VR6Will 0 Posted July 13, 2006 Author Report Share Posted July 13, 2006 right, so no actually experience of a 2.9 obd2 inlet?i will be converting my 2.9 vr from obd1 to obd2 soon and thought about cutting my obd2 manifold open just like gav_vr6 is currently doing, i was just curious to see if anyone had actually done this and what results they got with it. Link to post Share on other sites
ChrisP 0 Posted July 14, 2006 Report Share Posted July 14, 2006 where not talking obd1 here but obd2 and they alle the sameobd1 theres a big diff. but thats another treadMost people that know about VR's know that there is a difference between 2.9 and 2.8 inlet manifolds on OBD1' date=' the reason being that corrado 2.9's were OBD1, [b']BUT when the Golf VR Syncro changed to OBD2 along with the 2WD Golf VR in 1996 they gave the 2.9 (that was always installed with the syncro) a bigger manifold. So there is a 2.9 or bigger OBD2 manifold. I know this for a fact because I have one! See the pics below Link to post Share on other sites
FishWick 21 Posted July 14, 2006 Report Share Posted July 14, 2006 right' date=' so no actually experience of a 2.9 obd2 inlet?[/quote']No, what's the point when it has the same plenum area as the OBD1 2.9 manifold and I've already said the engine is better on the 2.8 OBD2 manifold?Why don't you just plug weld the throttle holes on a 2.9 manifold and redrill and tap them for an OBD2 throttle.......it's been done loads of times before.... Link to post Share on other sites
gav_113 0 Posted July 14, 2006 Report Share Posted July 14, 2006 so im i going to benefit by opening up my OBD1 manifold the same as a 2.9 manifold plus fitting a XXL TB? Link to post Share on other sites
VR6Will 0 Posted July 14, 2006 Author Report Share Posted July 14, 2006 No' date=' what's the point when it has the same plenum area as the OBD1 2.9 manifold and I've already said the engine is better on the 2.8 OBD2 manifold?[/quote']because your comparing obd1 against obd2, how can you say the engine is better on the 2.8 obd2 manifold when you have never tried the 2.9 obd2 manifold?Why don't you just plug weld the throttle holes on a 2.9 manifold and redrill and tap them for an OBD2 throttle.......it's been done loads of times before....that is another way of doing it... Link to post Share on other sites
RIX 0 Posted July 14, 2006 Report Share Posted July 14, 2006 if you have an obd 1 engine,you will gain something by changing from a 2.8 too a 2.9 manifold,but not on the obd 2 a they all have the big manifold period.compered too my obd 1 2.9 syncro the obd 2 only has a bigger tb,all obd 2 have 72mm tb. Link to post Share on other sites
VR6Will 0 Posted July 16, 2006 Author Report Share Posted July 16, 2006 if you have an obd 1 engine' date='you will gain something by changing from a 2.8 too a 2.9 manifold,but not on the obd 2 a they all have the big manifold period.compered too my obd 1 2.9 syncro the obd 2 only has a bigger tb,all obd 2 have 72mm tb.[/quote']obd2 inlets are not all the same, chrisp has even shown you a pic of an obd2 2.9 inlet - compare that to gav_vr6's 2.8 obd2 manifold, and you will see the difference! Link to post Share on other sites
gav_113 0 Posted July 16, 2006 Report Share Posted July 16, 2006 if you have an obd 1 engine' date='you will gain something by changing from a 2.8 too a 2.9 manifold,but not on the obd 2 a they all have the big manifold period.compered too my obd 1 2.9 syncro the obd 2 only has a bigger tb,all obd 2 have 72mm tb.[/quote']obd2 inlets are not all the same, chrisp has even shown you a pic of an obd2 2.9 inlet - compare that to gav_vr6's 2.8 obd2 manifold, and you will see the difference!mine is a OBD1 isnt it?? it better be? im getting confused now!wot are we talking about?? ahhhhhhh Link to post Share on other sites
VR6Will 0 Posted July 16, 2006 Author Report Share Posted July 16, 2006 it might be gav but the 2.8 obd2 looks the same as yours from underneath Link to post Share on other sites
gav_113 0 Posted July 16, 2006 Report Share Posted July 16, 2006 someone correct me if im wrong, but my understanding is that the 2.8 2wd obd1 and obd2 inlet manifolds have both small chambers, but they have different throttle bodys and different fitting holes so the TB are not interchangeable? mine is def obd1 because the TB is obd1, and it would not fit on a obd2 manifold? Link to post Share on other sites
RIX 0 Posted July 16, 2006 Report Share Posted July 16, 2006 i have a mate in dk,that drives an 97/98 vr with 75tkm on the clock,thats an obd2 car it has the same big intake as a 2.9 engine.you guys iven have and old tread where it also stats all obd 2 have the big manifold,it´s only on the obd1 cars that theres a diff. Link to post Share on other sites
VR6Will 0 Posted July 17, 2006 Author Report Share Posted July 17, 2006 someone correct me if im wrong' date=' but my understanding is that the 2.8 2wd obd1 and obd2 inlet manifolds have both small chambers, but they have different throttle bodys and different fitting holes so the TB are not interchangeable?[/quote']in the uk yes! correct!i have a mate in dk' date='that drives an 97/98 vr with 75tkm on the clock,thats an obd2 car it has the same big intake as a 2.9 engine.you guys iven have and old tread where it also stats all obd 2 have the big manifold,it´s only on the obd1 cars that theres a diff.[/quote']Ok i didnt realise you werent from the UK. In the UK 2.8 obd2 inlets are the same size as 2.8 obd1 inlets, sounds like from what you are saying in europe the 2.8 obd2 inlets are the same size as the 2.9 obd1 inlet. Link to post Share on other sites
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