Want 280-300bhp, what's the best way to go? One for the Techies.

[16v]

Hi,

I hope we get a good discussion going on this. Even if you don't know much I'd be interested on ANY thoughts, opinions or suggestions.

I'm no stranger to modding and I want to up the power of my Mk2 16v most probably by FI.

I've played a lot with FI before and have taken 2 UK spec Imprezas from 208bhp standard to 360 and 390bhp respectively.

Got a few ideas and need some advice/help.

I was initially going to start simple and fit a 9a bottom end for a bit more bottom end torque. However, I've heard the 9a doesn't like to rev as much as the 1.8 and I'm having great difficulty locating one, so I'm in two minds whether to do this or not. Also, see below, but my 1.8 bottom end it partly rebuilt so it seems daft to lose it.

It's also on K-jet injection which I'm told is no good for what I'm after and I'll probably need to convert to Megasquirt or Digi1 which is probably what I'll do.

However, saw some pics, I'm sure, of turbo'd 16vs still on K-jet so it must be able to sustain at least a decent power hike. Did BBR do a turbo conversion on the 16v maintaining the K-jet and doing around 220bhp?

Next, I'm wondering whether to go s/c or turbo.

S/c sounds best for the instance of response (don't want bags of lag). My mate has a Corrado G60 and was very impressed when I drove it. With only 180bhp it can hold it's own against 300bhp Imprezas up to reasonable speeds.

However, due to the high revving nature of the 16v I'm thinking maybe a turbo might be a better option, otherwise I'll have to restrict the s/c's boost or risk running it past efficiency.

VW did a few S/C'd 16v's though, so it must be practical. Wonder why they favoured s/c when sister company audi seems to favour turbos?

Just thinking with an S/C I won't have to faff about as much on the exhaust side and there seems more space to go the s/c route, although I suppose turbo manifolds are readily available.

I know there's the 20vt option but the car has had the bottom end mostly rebuilt (cranks regrind, new bearings, oil pump etc.) and the head is rebuilt and gasflowed, twin exhaust cams and ported inlet manifold so it seems a shame to waste all that. Kind of like the 16v engine too.

I'm also working to a reasonable budget as I've just had to buy a house and have a baby coming, hence the demise of my 390bhp Impreza

If anyone on here has turbo'd a 16v I'd love to hear from you.

[Dom Mk3]

I'd say you won't get near that power from a 2.0 16v on a "reasonable budget". Perhaps the two easiest ways for this are the 1.8T, or turboing a VR6. Neither shockingly cheap...

or just dump another 16v engine in the back buy a cheap volvo for practicality!

[topher]

you can get a turbo kit for about 2 grand.. not sure how close that gets you to 300bhp.

to supercharge your engine and maintain reliability at 300bhp will cost you double that easily.

[Organisys]

1.8T 'BAM' code engine swap cheaper and easier.

[...joe]

being that i'm doing a 16vt engine at the moment based on a 9a 300bhp is easily achieveable. alot of greif sorting out the exhaust manifold but not impossible fi you don't mind buying from the states.
k-jet was used on turbotechnics conversions as there wasn't much of an option back then so they added a 5th injector to keep up. i've heard of people adding andother as the k-jet can't cope at high bhp.
i also know a guy with a g6016v and the amount of work he did to get reliable power was such that a turbo conversion is alot easier, his corrado sounds incredible though!!! also he's now building a dub engine in his westfield and is going 16vt this time.

[16v]

Cool.

Thanks for the replies.

Joe, where's the best place to get a 9a? And would you definately go 9a for a 280-300 conversion of would a 1.8 be a better option? Especially given that it's virtually rebuilt already on mine.

Is the 2.0 less revhappy than the 1.8 due to the longer stroke?

What turbo choice you gone for? And how have you got over the k jet problem?

Sorry for all the questions. :embarassed:

Thanks

[Mk1Mad J - 16v]

  I've been in contact with bloke at Metrix Motorsport in USA (they supplied my 16v rocco inlet) here's a snippet of what he had to say 

I can supply you with all of the parts you would need to build a 16vt, or a complete motor. For starters I would not use the CIS fuel system. Bosch's CIS fuel system was an excellent fuel system for the time, but it has trouble keeping up with the fuel needs of a turbo charged engine. Under regular conditions, an engines fuel demand is linear. That is to say more air is introduced into the cylinder as the rpms increase there it is easy for a fuel metering device to gradually add fuel. A turbo engine on the other hand will be much the same at idle as the NA engine, but when it comes up to boost it will need much more fuel. CIS cant handle an exponential fuel curve..
 
OK so for a fuel system, I recommend one of two systems. The first is the Digifaunt II system from a Corrado G60. This system uses a barometric sensor to determine manafold boost pressure, and does a great job at adapting to a turbo application. I used one of these systems for a while with my first 16v turbo. With 350cc fuel injectors, and 20lbs of boost. the motor was generating somewhere around 250 BHP.
    The other fuel system I would suggest, and the one I use on most of the engines I build is Megasquirt. This is a standalone Fuel injection system which provides everything you need to make Lots of HP, it is a real time system so you can plug your laptop in while you are driving and make adjustments form the cockpit.
 

(Note the bit i've highlited in red  )
Engine wise, I would suggest a 1.8L 16V simply because you can use G60 corrado internals. The G60 bottom with a 16V head is a perfect set up. The 2.0 16V will cost way more to give you the same power. The cool thing to remember is with a turbo, you can turn up the boost and fuel, and increase the displacement of your engine. For example a 1.8 16V @ 1bar boost is equal to 3.6L because you stuffed atmosphere + one more atmosphere into the combustion chamber. therefore doubling the mechanical efficiency of the motor. Another nice thing about the 1.8 is the G60 crank if forged, which is way stronger.. I also have all of these parts in stock.


Useful websites:-
http://www.eiptuning.com/eip/16vturbosystem.html
http://www.c3cars.com/VW/16v/
http://www.ffp-motorsport.com/other/jyns02/index.php
http://stores.ebay.com/Metrix-Motorsport

[VeeDubGTI16v]

i think there is a way of using k jet but from a volvo or saab turbo kjet, it will be crude though. think about what the boost will do to the metal flap in the airbox

[...joe]

i'm going to be using g60 wiring, thats how i got over the k-jet wiring! i got the 9a because it was available at the time. not quite sure why using a 1.8 would be better than a 2ltr, but i'm using kr cams and getting the 9a pistons notched to lower the compression, while getting the crank, rods, flywheel etc balanced and lightened.
i'm using audi s2 inlet, exhaust and turbo for now but i don't like how it looks! so in future i might change the exhaust for another and run a garrett t28 or something like that. i only want about 250bhp partly becasue of traction issues and partly because i can run it under full potential which should make it a bit more reliable. i've been reading lots and am building it slowly as i only want to start doing it at the end of the year.

[Mk1Mad J - 16v]

not quite sure why using a 1.8 would be better than a 2ltr,

Its not necessarily better but you can use the forged parts out of a G60