I'm looking for a 4 branch for my kr, but I need one that will mate up to a stock sized system as I have just got a nice twin box stainless oe style system. I have seen some being sold on eBay for 175 that read like they will mate up to the oe 55mm pipe work, or are they naff? Karl
Not needed, the cast manifold works well for standard engine. If you want to spend money on the exhaust, get a downpipe from Saxon.
^^Needs other tweaks to justify ...I know Karl says it runs "spot on" to him, but if the car cannot deliver a suitable acceleration profile at WOT, typical of a good working example, then it needs looking at before adding any other hardware.
It does seem to pull well.... Just not turbo well lol. Main reason I want to ditch the oe down pipe is it has a massive silencer built in! If it breathes a little better and sets it up for more mods later on then job done. Looked at Saxon but its very expensive for the system! I'll ask about a downpipe but I'm guessing it won't be cheap
Who says it will breathe better than it currently does w/o the d/p front box . They sure do work well on ABF conversions You were spoilt by that low speed turbo thump, that is the problem. The closest you will get to that would be 2.0 16v power and short gearing
With out the silencer in there it will flow better... There will be less back pressure, and in theory with smother header pipes it should flow a little better too. I might. It get massive gains on a stock engine, but it is laying the foundations for later on if the kr stays
Karl, What you saying is not incorrect on face value and a principle I am familiar with, but I would like to see more evidence of that theory working in this example, having owned 2 mk2 1.8 16v on K-Jet, std and then optimised, ABF K-Jet optimised, access to ABF digifant 3.2 vehicle and now ABF MS. I have had all on factory exhaust systems sans the ABF digifant 3.2. I have also driven, tweaked and tested many 16v vehicles with the long primary exhaust headers, both KR and ABF, that were not setup properly and they drove pants. Once set up the drive was similar to a vehicle with a stock system. My old KR lump could achieve acceleration rates of 0.29g @5.5K in second, where as my ABF K-Jet conversion in the same car up 0.35g@5300rpm. All tests ran the factory exhaust, including the 16v downpipe and the same gearbox/wheels. Information like what I am suggesting is what we need to see from your car, to establish baseline, which can determine if it really up to speed as you suggest. Or I can take you out in JORAN and you will instantly see what I mean I know shiny parts are tempting and your 20vT has left reference in your mind, but at this stage not worth it in my opinion and experience.
I've just downloaded a g meter for my phone, so ill have a play on tues when I take it to work. I know silencers and their design infulance back pressure, as in my job I type approve after market silencers for drive by noise and back pressure, the replacement vs the oe silencer, and some times we test a car where from the factory I could have had just 1 rear silencer, or second higher up in the system, and the back pressure with a second silencer is higher. The slower the flow rate the less scavengeing you get, but I do agree a badly set up system won't help anything.
The Gs in the phone app can be used to determine the general accel behaviour, but may not correlate to the profiles I have generated from Gtech, in second gear and 1/4 tank for fuel, 195-50-R15 wheels etc. Bear that in mind. OEMs engineer the powertrain with an acceptable amount of back pressure when generating homologated engine power curves. These power curves are done with production intent exhaust system fitted. So when you signoff an aftermarket exhaust system you are working with a legal standard for drive by noise as well as a back pressure limit set by the OEM of the powertrain. So if an exhaust system has less back-pressure than specified by the OEM, it may influence improved scavenging at the header at certain engine speeds, which has to be accounted for by the engine control system. In STD OEM NASP engines this effect can be very small, however if the engine is significantly tweaked the back pressure limit can be breached if an "free flowing" exhaust was not fitted. For our 16v older cars we would need to know what is back pressure limit for the engine during a WOT sweep and if the 2.25 full 16v 4 box exhaust system breaches this threshold at certain points of measurements. So I understand what you are saying can go on to add more from an OEM perspective, however in you specific MK2 Golf KR case I am still not convinced shiny bits are needed.
Fitting race parts to an otherwise standard engine can have mixed results. That race manifold is designed for a high revving race engine. You may find it does nothing or even has a negative effect on a standard KR.
I had this manifold on iterations of engine from 180 to 230hp, so not for high revving race engines especially, seemed pretty good to me! Got a larger bore manifold now to explore higher power outputs, Very much for high revving race engines. This is why my original is for sale.
A 16v manifold with say an ABF downpipe and de-cat pipe to delete the silencer would surely provide adequete flow through a 4-2-1 setup.
http://www.tsr-performancestore.com/tsr-mk2-golf-4-branch-manifold-845-p.asp TSR are a pretty reputable outfit, and have a rolling road to test these things, so I have no reason to disbelieve their claims. Also the exhaust design is what you would expect to work (pipe diameters/lengths etc). With my new Simpson manifold, I had the car on the rollers before and after and gained 30hp in the midrange. Hope you enjoy the data.
