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What's needed for a solid 300bhp in a 2001 S3?

Discussion in 'A3/S3 Forum (8L Chassis)' started by awesomeaudio, Jan 30, 2010.

  1. awesomeaudio
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    awesomeaudio Member

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    heya all,

    Just looking to start getting parts together to improve the power of my 2001 model s3 as i sold my impreza sti to a friend as much preferred the classy and nicer driving s3 but am after getting it close to 300bhp as this is the kinda power my subaru was and were going on a trip to the nurburgring so would like to atleast keep up! but wondering if im missing any parts out and if it really is possible without turbo upgrade or internal work!

    so far im guessing

    exhaust
    sports cat
    forge re circ
    front mount cooler
    panel filter upgrade
    and a custom map

    i may be totaly wrong and please correct me if i am but thats what me research so far has brought up!:faint:

    any way be great to know what is needed to get a solid 300bhp or area of!
    #1
  2. 1animal1
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    1animal1 The Clar!! it mouves!!!

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    if you want to be shy of 10bhp then you may manage it....if you want to imagine you have 300bhp then o thesemods and get on Awesomes rollers :) ....if you actually want 300bhp you need a hybrid KO4 im afraid
    #2
  3. MintyS3
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    MintyS3 Works 60% the time, Everytime.

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    You will keep up with a 300bhp impreza with a mapped S3. But yeh hybrid for 300bhp.
    #3
  4. awesomeaudio
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    awesomeaudio Member

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    was afraid of that!! is hat the most you can really get out of the standard k04 then around the 280-290bhp mark?

    didnt realise an s3 with a map would keep up with a scooby of around 300bhp they seem so agresive compared to my s3 wich in ways i dont like but then other times kinda wish i put my foot down in the audi and it went crazy lol! just seems so tame atm!

    thanks for the replys tho, and any idea on cost of a hybrid k04 or getting mine done!
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  5. MintyS3
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    MintyS3 Works 60% the time, Everytime.

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    Your looking at 250-260bhp with a map. Torque will be very similar to a 300bhp scooby. Maybe a little more and coming in earlier than the boxer engine. As I said you will keep up but unlikely to beat. Im going to the ring this year with an s14 silvia, gt4 st205 and an impreza sti ra. Funnily enough they all have about 320bhp and I dont have any issues keeping up.
    Last edited: Jan 30, 2010
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  6. emery1990
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    emery1990 Active Member

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    The hybrid turbo if you trade yours in, would cost about £800 im guessing, as i asked about k03s hybrid and that was £600. You can get a custom map to make the turbo's power delivery more agrresive probally. So your looking at over a grand easily as a hybrid turbo is stage 3 remap, costing around £600 itself.

    If you havnt got your handling sorted, thats whats going to keep you behind mostly. If the scoobys handling is better than yours that is anyway, if not then youll only be behind on power.
    #6
  7. <tuffty/>
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    <tuffty/> Badger 5 Edition Staff Member Moderator

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    Sadly, a genuine 300bhp is pretty much unachieveable using a K04 (hybrid or otherwise).... Seen a lot of these types of conversions in Ibizas and LCR's, 280bhp and over 300ftlbs is all you will get as the K04 just doesn't have the flow capacity for any more. IMO of course... dyno lottery may well give you an assumed 300bhp but in reality the poor little K04 can't manage it and even if you wack the boost to silly levels to get some air through the engine it will be very spiky and you will need rods to cope with the torque spike...

    300bhp may be doable with a GT28rs or similar but you will hit the limit of flow capabilities of the exhaust mani and the hotside on these types of turbos...

    <tuffty/>
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  8. awesomeaudio
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    awesomeaudio Member

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    that information really helps, so many people seem to think just a map gives them over 300bhp! and as very well stated rolling road arnt always tat accurate! hmmm well i really didnt want to get into turbo work just for the sheer fact of one i wouldnt trust myself doing it and two if it afected reliability!

    I realise you cant have both tho!

    when you say you keep up, as in can stick right behind them or keep in a distance of them???
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  9. S3 HODGE
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    S3 HODGE Brown passenger seat.

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    Its mainly down to the driving skills and handleing at the end of the day....The scooby's could be running 400BHP but with no handleing mods and without a decent driver, you will be all over him ;)
    #9
  10. <tuffty/>
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    <tuffty/> Badger 5 Edition Staff Member Moderator

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    Why not? I run a GT3071 big turbo and its more reliable than a maxxed K04 hybrid....

    <tuffty/>
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  11. ianysm
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    ianysm Active Member

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    I think a mapped S3 wouldn't be far behind but given the same standard of driver in each the S3 out of the box just doesn't have the handling or braking. It would take a decent scooby driver to reveal that though...I haven't found one yet!
    #11
  12. awesomeaudio
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    awesomeaudio Member

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    haha love it! the end of the day id love just to keep up as then not only then do i have speed which in my opinion from owning imprezas is all there good for also have the looks and comfort of an audi!

    Would love to see the diference in the turbo's i imagen it would feel like a totally diferent car!

    i suppose i should get saving then if the bigger turbo is the only way, ive got a few bits for the car already with the front mount to finish and am looking for exhaust and sports cat an apr if i can find where they sell them!
    then hopefully map it for now would be good if i could be around the subaru's kinda perfromace for now

    thanks for replys
    #12
  13. voorhees
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    voorhees Moderator Staff Member Moderator

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  14. S3 Nattie
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    S3 Nattie Quattro ist für sissies

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    Get yourself a 3" downpipe also as these are meant to be restrictive on s3's. Hybrid turbo doesnt cost that much if you use your own turbo, about £450 500.

    I have kept up with a standard 04 sti with a near enough standard s3 so I think a stage 2 would be enough for a 300bhp sti etc.
    #14
  15. S3-Andy
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    S3-Andy Member

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    My revo mapped s3 is not a patch performance wise on my old jap spec sti, the S3 is very tame, i was in the same boat when i first crossed over.
    I think it would need serious money chucked at it, cant complain about the quality and ride in the audi though.
    #15
  16. jojo
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    jojo S3 Drift King! Staff Member Moderator

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    Let's be realistic here, S3(remapped) vs STI is not even a contest is it? We're talking about 1.8 vs 2.0 displacement here, the STI is not even pushing the limits of the turbo out the box, where the S3 requires a remap just to make similar power. Anyone who brags about their S3 torque figures need to double check there torque curve, how long does the K04 sustain that torque? it probably hit's it for a micro second before it drops back down again lol. Honestly, if your S3 can keep up with a Subaru Impreza STI, then it's more of a case that the STI driver is pants than your car is great, and I'm an S3 driver!

    Safe driving anyways. :racer:
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  17. S3-Andy
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    S3-Andy Member

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    To be honest i dont class the audi S3 as a aggresive hot performance motor, in my eyes i see it more of a quality motor which when remaped is reasonably quick,
    It dont bother me too much as i have the bike for fun,
    #17
  18. jcb
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    jcb Active Member

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    I don't see the point in spending that much on a hybrid that will be seriously stretched to make your power goal. A Ko4 will make 300bhp as stated but at that point your exhaust gas temps are sky high and the turbo is pumping very hot air. Your chances of dropping a valve head, detonation/pre ignition etc just become so much greater.

    A Gt28RS will cost you less than $900 in the US, even with tax you are laughing. even then you are stretching it to stay at 300bhp. 2871/3071 is your answer for reliable 300
    Whilst 300bhp is easily within the limits of the stock rods a blown engine for the sake of $300 of rods is nuts IMO.

    A larger turbo at lower boost working well within its effeciency range is always going to be more reliable than a stretched and squeezed smaller one.
    #18
  19. Westy
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    Westy Double Dark Side! Diesel & 8P

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    I was thinking the same Jo, I cant see an S3 being much of a test to an STI I just didn't want to comment as I have only had a go at a P1 and that was a waste of time!
    #19
  20. S3 Nattie
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    S3 Nattie Quattro ist für sissies

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    Well my friend has a standard 2004 STI and when we had a quick play the other week, few times there was noting in it for 40 to x amount of mile an hour, I wasnt that surprised either. If he got me when I wasnt on boost I was left for dead but that rarely happens. Ye goes to show about the driver skill but alot of people say a S3 wont beat this car etc but I dont agree with some of them from my experiences.

    STI aint nothing special and are not rated that high by few my friends who are jap lovers.
    #20
  21. indiemike
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    indiemike ZoomZoom

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    From whats been done to my car i think ive got to the limits of bhp without touching the Turbo
    I fancy breaking the 300bhp but for the price of the hybrid im not sure its worth it for the price and going towards a BT i havent got £3k+ to spend
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  22. MIKE GTR
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    MIKE GTR Member

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    Most engine builders will disagree - you buy a turbo that is at its most efficient at the power you are aiming for - the fact of the matter is that a lot of people buy big early because they plan to increase power along the way, a GT28rs running 300brake against a K04 running 300 brake is definately going to be slower on the road and poss the track too - as for reliability, the way that big turbos deliver the power is more likely to cause breakage than a small turbo due to the bigger 'bang' when they come on and the higher revs req'd to keep on boost - as for det etc its only a prob now days when people who have no knowledge get involved - most management systems have sufficient parameteres to retard ignition when detecting pre ignition etc.

    My advice would be if you're happy with 300brake then go for a Hybrid K04 - i've just bought one but simply because my old turbo needed a freshen up and it only cost me £350 to have it redone hybridized.
    #22
  23. <tuffty/>
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    <tuffty/> Badger 5 Edition Staff Member Moderator

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    I disagree with this statement I'm afraid... bigger turbos do deliver power differently to smaller ones like the K04 but certainly not as spikey as a small turbo especially at sensible levels of boost... granted the further away from base horsepower you go then the larger the difference you feel when the turbo comes on boost but a big turbo delivers much more steadily than a K04... higher rev limit is required not to keep the turbo on boost but more to give you your powerband back... bigger turbos will spool later than a K04 and have the flow capacity to maintain sustained boost at higher RPM... By not upping the rev limit you are just narrowing the power band and losing out on potential for more horsepower... my GT3071 produces 0.5bar at around 3.2k rpm and is on it by 3.9k at which point it will hold (currently) 1.4bar to the redline... there is no boost spike like you get from a maxxed out K04 just smooth power delivery.. You are more likely to bend rods from a maxxed K04 running high boost than a GT28/30 running low boost... running just over 1bar on a GT30 should give low 300's ftlb torque and 330/340 bhp and having a small hotside (I have a 0.63 a/r) will help spool... my cars very drivable and isn't a monster at all...

    [​IMG]

    <tuffty/>
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  24. MIKE GTR
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    MIKE GTR Member

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    I'm not disputing the benfitis of a big turbo, (even though your graph proves my point about delivery - 240brake jump 2000rpm IS a big hit on both the clutch and box) i've got a T78 on my skyline that comes on boost at 4500rpm and holds all the way to 9000rpm - and trust me it kicks in a lot harder than the standard turbos ;) and i'm sure my gearbox will agree with me even if you don't.

    My point is that you have as small a turbo as possible to get your power, simply for drivability, durability, and reliability (as in, its not on the redline the whole time because the powerband has been moved so high up the rev range) .

    Maybe this will help - We all know heat kills engines and yes a bigger turbo creates less heat resulting in a more reliable turbo and ancilleries - well why aren't T78's fitted as standard then?
    #24
  25. <tuffty/>
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    <tuffty/> Badger 5 Edition Staff Member Moderator

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    ...a std K04 installation running on std boost doesn't create as much heat as one that has been mapped, the inefficient exhaust manifold and maxxing the K04's flow capacity are the main contributors to it generating more heat than normal... A big turbo maxxed out will be in the same position, you push it beyond if efficiency or use a poor manifold design then EGT's will rise and you will still generate excessive heat...

    Larger turbo running low boost will produce more power and reliability (heat wise) than a K04 maxxed out... however of course this will be at the expense of spool and subsequently throttle response/drivability which to answer the question is why manufacturers use smaller turbos on cars such as the S3 as its not all about producing maximum power but the feeling of power... most people out there would get cheesed off really quickly if they put their foot down in town traffic only to find themsleves in the back of a bus when turbo lag has been overcome and boost has kicked in :)

    IMO anyways....

    <tuffty/>
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  26. S3 HODGE
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    S3 HODGE Brown passenger seat.

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    Hmmm the Joys of this Forum :)
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  27. MIKE GTR
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    MIKE GTR Member

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    Agreed, my point was rather tongue in cheek - unfortunately you have to sacrifice things in the search for power - be it MPG, Reliability or drivability - My inital point is that you should build your turbo around your engine and not the other way round - i.e if you want 300brake then you go for a turbo that has the best drivability/reliability etc for 300 brake - that may or may not be either a GT28 or a hybrid K04 - it may in fact be neither!
    #27
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  28. MIKE GTR
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    MIKE GTR Member

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    So what is the best turbo for 300brake?
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  29. Westy
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    Westy Double Dark Side! Diesel & 8P

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    Stir it up :)
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  30. MIKE GTR
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    MIKE GTR Member

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    LOl well maybe a little, but i've just had a Hybrid K04 fitted, not because i want more power simply because it was the same price as having a std turbo.

    I've got miltek cat back, forge recirc, front mount, revo (stg 1 i assume - will be remapped when back) and sort of expected at least 300brake - i mean if after all this i only get a 90brake increase over standard to must be a pretty poor design engine
    #30
  31. Welly
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    Welly VX220 SC Driver :)

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    It's not the engine, the engine is good! Proven to be able to handle 400BHP+ (Well, with some internal mods). In my mind that on it's own out of a 1.8 shows a good engine design.

    Its a combination of a ***** design manifold which is very restrictive, and a small turbo. A hybrid K04 turbo is still a small turbo.

    If you want big power. New manifold, BT, good map.

    End of.
    #31
  32. Westy
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    Westy Double Dark Side! Diesel & 8P

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    Make that 600bhp in Bills case.
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  33. Welly
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    Welly VX220 SC Driver :)

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    Granted, but that one is just a little bit special.....

    And cost 100 million quid....lol
    #33
  34. MIKE GTR
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    MIKE GTR Member

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    If i added all the above bits to my skyline or even a cossie (+ uprated injectors), i'd see a damn sight more than 90brake increase. I know its not an apples and apples comparison, but the costs involved in the bits i've got to get to this spec are ridduclous.

    I don't want a big turbo, i just wondered what was needed for 300brake, as some seem to think the Hybrid K04 won't manage it
    #34
  35. Westy
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    Westy Double Dark Side! Diesel & 8P

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    Just goes to show what you can get from the 1.8T VAG engine though. Also Tuffty has managed 380ish bhp from very little mods and a GT3071 turbo.
    #35
  36. Welly
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    Welly VX220 SC Driver :)

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    This is exactly my point dude. What an engine. A little 1.8. Awwwww. Great engine design, complemented with a crappy exhaust manifold and a hairdrier turbo.

    Deep joy.

    (They aren't that bad really I guess)
    #36
  37. MIKE GTR
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    MIKE GTR Member

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    Renault were geting 1200brake out of a 1.4 in their 1982 formula 1 car, i think its more a case of how deep are your pockets, not how good is an engine.

    In my eyes a good engine is a std engine that can take a good increase without internals, i.e. a Toyota Supra, rumoured to be able to take up to 800brake on near standard internals
    #37
  38. Welly
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    Welly VX220 SC Driver :)

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    Yep. And the answer? Not bloody very!

    Myself included. You will get close. Very close when combined with that new JBS Cast Manifold which will aid flow.

    I'm not saying it's not worth doing mate, I'm considering pitching up the cash and getting the aforementioned... I just don't think a solid and/or reliable 300 BHP is realistic out of a turbo that small.
    #38
  39. MIKE GTR
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    MIKE GTR Member

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    I see yours is roughly the same spec as mine, bar the downpipe. is yours gutless? cos mine bloody is and its supposidly 260brake lol
    #39
  40. Welly
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    Welly VX220 SC Driver :)

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    To be fair, I wouldn't say it was gutless... In fact I think it goes quite well for what it is to be fair. Pulls really strong and hard, but to be fair, was gash on the standard N75 Valve, the J made such a difference.
    #40

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