1.8t 20v 325-350hp - whats required?

[badger5]

since the gt3071r .63 turbo is capable of 32+psi this is relevant.Bill, what do you prefer/recommend for street driven cars. A bigger turbo like the GT30r at moderate boost say 18psi or a smaller ko4 running at full chat.Which one stresses the motor less?

bigger turbo less stressed vs its later power delivery is your decision

 

[badger5]

Whichever makes most power will stress the engine most. Cylinder pressures and stress on components isnt simply a function of boost. If they are both performing at the same Ve then stress on engine components is the same. So whilst the ko4 which will be making more boost for same power as gt30 at low boost, will be under more stress, the engine itself will be under no more or less.

What you should ask is which turbo is under more stress, or which is performing at a higher efficiency to acheive the same result.

unless we are talking thermal stress as opposed just delivered torque output...
k04 looses out on that basis... small turbo working harder = more unwanted heat

Pro's and Cons'... You cant compare k04 with GT30 framed turbo..

 

[antwan64og]

Whichever makes most power will stress the engine most. Cylinder pressures and stress on components isnt simply a function of boost. If they are both performing at the same Ve then stress on engine components is the same. So whilst the ko4 which will be making more boost for same power as gt30 at low boost, will be under more stress, the engine itself will be under no more or less. What you should ask is which turbo is under more stress, or which is performing at a higher efficiency to acheive the same result.

yes psi is irrelevant, the air flow in CFM is relevant to power.However, a smaller turbo spinning faster can start to push warmer air through increasing risk of detonation.Also some engine configurations don't take low rpm/high torque too well (BMEP x rpm) and the delivery of the torque can be important to breaking stuff.I'm not talking about peak power

 

[solaris]

I've got some 550cc injectors for sale see the classified section
Classifieds: Genesis 550cc injectors including adapters

 

[jasongtr]

about £25 cheaper than backdraft sell them for then...

 

[Gops]

Drop a 64 in and youll be happy

 

[IrishDave]

^^ Don't think i would be too happy with a commodore 64 anywhere near my car.

 

[Prawn]

Would love to drive a GT30 car back to back with mine, it's been a long time since I've been out in a big turbo car, but I'm really LOVING my k04-064 at the moment, I think it's about as close to the perfect turbo as you're going to get all round.

 

[antwan64og]

High Flow Cast Up-pipe for 1.8T FWD Golf/Jetta/Beetle/TT : atpturbo.com

If your gt30 has a compact compressor housing couldn't you use the ATP up pipe from the above link?
Saves having to buy a new manifold

 

[jasongtr]

mine has a T3 flange,

also my downpipe is a V band fitment not a bolt on jobbie

 

[Prawn]

that up pipe is a neat idea, but in reality, pretty horrid.

It adds a joint to leak / blow, and also retains the **** stock manifold which is tiny and cracks, seems like an all round compromise.

Also, that's ko3 fitment too.

Personally, I think you're possibly heading into the realms of 'more trouble than it's worth' with a gt30 build on the mk2.

Fair enough if you wanted ALL the power from the word go, and set out to build an epic monster, but going down the gt30 route because you already have the turbo is still going to end up costing a fair old chunk I reckon

 

[jasongtr]

its an idea I'm exploring due to having the turbo, most other things that are associated with that route would be done anyway

 

[jasongtr]

do you think for the 350hp region ill need anything other than a std agu large port head, or would it be wise to upgrade the valve train?

Im thinking of the options, using a KO4-064 or a GTx2867 turbo so it will spool earlier and then theres not a lot of need to raise the rev limit

 

[superkarl]

Valvetrain would only be needed for high revs. So if you were going gt30, valvetrain might be a good idea.

For a ko4-064 you wont need it, a stock head will be fine. Just change exh valve guides and stem seals as a service.

Gtx2867 over a ko4-64 would depend on the setup, i.e. Housing etc. As an internal one will be no better than a ko4-64.

P.s. I have a gtx2867, and still think the ko4 is better when comparing to an IWG varient

 

[jasongtr]

ok cheers, I've got an external tial 38mm wastegate but building a setup around that is more stupid than deciding to build one around the gt30 i have.

Does anyone have any prices on a complete K04-064 kit for the 1.8t yet?

 

[jasongtr]

also whilst i think of it, i have a LINK G3 ecu - was on the mr2 turbo that the garrett gt30 was on, how are they considered as stand alone ecu's for the 1.8t 20v engines, mine has a 5 bar map sensor fitted too.

 

[superkarl]

ok cheers, I've got an external tial 38mm wastegate but building a setup around that is more stupid than deciding to build one around the gt30 i have.

Does anyone have any prices on a complete K04-064 kit for the 1.8t yet?

if you wanted to step it up a notch than the ko4 you could use that wastegate, get yourself a gtx28 or the gt30, t3 or tial housing, suitable manifold etc etc, and see way in excess of 400hp. But its all extra ££££



there isnt a kit as such, i think dan might just supply hardware to adapt and install the ko4. The turbos are only circa 500 second hand.
this is what most are telling you, the ko4 is biggest bang for buck. Obv there is lots of custom fab like a BT build, but its cheap.


you just need to decide whether the extra 50hp for e.g. Is worth it

also whilst i think of it, i have a LINK G3 ecu - was on the mr2 turbo that the garrett gt30 was on, how are they considered as stand alone ecu's for the 1.8t 20v engines, mine has a 5 bar map sensor fitted too.

stock ecus are adequate for most builds, no point in standalone

 

[jasongtr]

ok cheers, i was told by someone recently that the later ecu's iirc he said bosche 3.5 ones on the later s3 etc are the better ones to use, obviously ill need the cats coding out etc, won't need on on a 1985 mk2

 

[<tuffty/>]

ok cheers, i was told by someone recently that the later ecu's iirc he said bosche 3.5 ones on the later s3 etc are the better ones to use, obviously ill need the cats coding out etc, won't need on on a 1985 mk2

ME 7.5 is what I think you mean dude... ME7.5 is drive by wire so you need to sort out a pedal box that supports DBW... you would get hydraulic clutch capability too... bit more work to do and depends on the gear box you use of course... 02J's tend to be a little weak on high power setups... Prawn now uses an 02M six speed in his A3... 02M should fit a Mk2 I think...

Bill uses DTA standalone ECU's but Emerald are pretty good too...

<tuffty/>

 

[jasongtr]

02M gearboxes are too heavy (although seem very strong compared with the O2J), and the mounts are a pain to try and get hold of for a mk2 fitment


edit: just found that dutch build sell the gearbox mount for an O2M to fit in a mk2/3 car

 

[Sam_]

"lag" is really overplayed by people like Clarkson on the tele, testing a high power car and then expecting it to make power at really low RPM when in reality everyone's going to drop it a peg or two.

Here's a GT42 on a 2.0 16v in a Mk2. I bet he's gutted with the "lag":



It's obviously a completely different ball game, I'm just saying it's a bit of a moot issue that can usually be compensated for. You're best off worrying about other things.

 

[jasongtr]

holy F**** thats quick - anyone else think its a bit too mental not to have a rollcage?


personally thats the way to go - haldex 4wd, but trying to find someone that can do it is difficult, unless anyone knows on here?

i can supply the parts including a 4motion/s3 floorpan i just need someone that knows what they are doing to fab it all up

 

[Prawn]

Argh. 02J, the very sound of it makes my ears bleed.

After 8 02J boxes i finally threw in the towel and went 02M. fecking hated the 02J's in the end.

many of the mk2 boys seem to go 02S from the mk5, 6 speed setup on 02J mounts.

Of all the options, I'd definitely forget the gtx28 idea, it'll still spool 1000 rpm later than the k04 064 and make similar top end to the GT30 you already have.

The GT30 would be good, just bare in mind you need revs to make use of it, and capping it to a low figure you'd still have all the downsides with none of the gains of the epic top end.

All comes down to budget really, plus potentially how much you can put down through 205 tyres also!

 

[jasongtr]

need to find someone that can haldex the mk2, why would i be limited to 205 tyres?

 

[Andrew@A.L.D]

Here's a GT42 on a 2.0 16v in a Mk2. I bet he's gutted with the "lag"

58 psi of boost

 

[jasongtr]

just bought a syncro to use for the rear floor and the tunnel - 4wd mk4 project underway….