5exi on order...

[Patrick]

Originally Posted by nutter

I dont expect the build to be ever finished

Welcome and yeah that's pretty much how it is, no matter how
much you do there will always be something to improve upon!

[5exiAdam]

Here is some detail from Integrated Engineering in the states on what to do to the audi lump to make it purr like a pussycat with Bronchitis!

My lump is the 180bhp from the Seat Leon Cupra.

Stage “1” – basics for reliability and make 400bhp

-Use any late 1.8t block w/ big port head
-82mm 8.5:1 cr JE piston / IE rod combo $824.99 -- OR – 82mm 9:1 CR Wiseco piston / IE rod - $784.99 (both in stock)
-Use stock main bolts
-Stock head bolts @ $34.99
-Stock main bearings @ $54.99
-ACL Race rod bearings / calico coated @74.99
-Stock head gasket set $139.99 (includes every seal in top end)
-Supertech Inconel exhaust valves- $259.99

I would recommend a T3 flange, .63 a/r GT3071R with that combination and expect 350-360 at the wheels on pump fuel. I would turn the engine to 7500 not much higher for good reliability.

Stage “2”
-Replace stock main bolts with ARP’s @104.99
-Replace stock head bolts with arp studs @ 194.99
-Same piston / Rod combo options
-Add a supertech spring and retainer set @ $449.99
-Add Cat Cams 1013653 grind camshafts @ 629.99
-Use an SEM or ross machine racing intake manifold – between $700-850 depending what you choose

With this I would use a T3 flange, .63a/r gt3071r… I would expect 400-410 at the wheels on pump and turn the engine 8000. Usable powerband is actually slightly longer, turbo takes about 200rpm longer to spool and you can rev it 500 higher so….

Stage “3”
-Replace piston and rod combo with 2L stroker kit @ $1699.99
-Replace oem main bearings with acl race calico coated @ $149.99
-Use a full supertech +1mm over valve set with single groove keepers $469.99
-Consider cat cams 1013658 but toss up there with the smaller 1013653’s- same price
-Have the head ported

I would proooobably stick with the gt3076r for this just because I don’t think you really need over 500whp in that car anyways… I’d expect close to 450whp on this setup on pump fuel, with more powerband yet again and much more torque out of boost as well. This is essentially the setup we use when looking for over 700whp, although we do some additional reinforcing like billet main caps etc which are not necessary for your power goals. The 3658 grind cams will take more off the bottom end and stick it up on top and of course bolster the peak numbers, but that camshaft does have a bit of a lopey idle and it does start to get quite soft on the bottom end.

I don’t know what you are doing for engine management but on the first setup I would use a 630cc injector file on stock ecu, second two I would go with a 870 or 1000cc injector file depending on who you are using for chip tuning. I recommend unitronics or eurodyne, but definitely do not recommend revo. If you are going to use a standalone ecu like pectel or similar then it is not an issue, although the injector sizes I suggested will work well regardless.

What you do for a flywheel depends totally on what transmission you use. My suggestion is of course to ditch the dual mass one as they are difficult to resurface properly and tend to break- I recommend a 12-17lb steel unit. I do not recommend the lighter aluminum ones (then that) as they cause a lot of gear chatter and in high rpm / high power I have seen them burst! Scary stuff… Shrapnel everywhere. Also beware of cheap “billet” steel flywheels which are actually cast iron cores not from true billet steel. Many of my friends have ripped the centers out of these with high power so I suggest them only for cheap oem rebuild type duty… K03’s, all that sort of stuff are fine with them. A good billet steel flywheel typically runs $3-400 depending on the transmission, with a ring gear.

We are still a bit back and forth on the clutches but have had good success with the south bend stuff. Given this car’s duty I would suggest a fairly aggressive clutch with a “6 puck” disk- this will make it shift a little quicker as it has a lot less inertia. An unsprung center is tougher, but will chatter pretty good when you let out the clutch in 1st gear / get rolling. We are just getting done putting an unsprung 6 puck in our mk4 and my mk2 has always run with unsprung centers. That’s just a question of reliability versus what you can live with…

[alackofspeed]

Leon Cupra if drive by wire is an AUQ engine with small ports. So if you're chasing power, are you going to source an AGU head?

[5exiAdam]

From my research so far, (But please do correct me if i'm making an arse of myself)

Big head codes - AEB AGU ADR AJH

Definately going big head route! They are so hard to find though.

Pick up engine on mon/tue next week.

Got engine, box, loom, ecu, driveshafts, hubs, turbo etc for £675

And only need to drive 40 miles to get it!

[nutter]

And check out the total price !
Bit much for me to go all the way with that (at least for now)
I am also now looking for a seat leon as donor,
Audi A3s for donors are really hard to find.

[limpabit]

If it was me, I would go with the standard power (even 180 is quick in this car trust me!). Get used to the car then make more power at a later date.

But do the job properly. Chargecooler is a must. Baffled sump and remote oil cooler if going on the airfield and track days optional.

[nutter]

Originally Posted by limpabit

If it was me, I would go with the standard power (even 180 is quick in this car trust me!). Get used to the car then make more power at a later date.

But do the job properly. Chargecooler is a must. Baffled sump and remote oil cooler if going on the airfield and track days optional.

Funny that, I am in exactly the same train of thought

Its all good having power, but you have to be able to use it, you have to get it through tyres and onto the road. Without modeern driver aids like traction control.

I have to say thou the numbers are a very imperssive reem of statistics

[5exiAdam]

I would prefer to to do it once and do it right.

Oil coiler, sump etc is a given. Yiu guys seem to prefer air/water charge coolers to standard intercoolers.

Is this just a space issue or is there another reason.

[limpabit]

You don't really have the space in the rear for an intercooler setup. A decent size one that is needed anyway. The side air vents are small.

And running boost pipe to the front is a long way to go. My way of thinking anyway.

[nutter]

There is no right or wrong way to do fit out a kit car.
If you want 410bhp, giving you 800bhp per tonne on this car, then thats your choice.

For me I dont want that amount of power on my right foot. Not because I dont want it, because I dont need it, and hence can't justify the expense.

[limpabit]

Your car will probably weigh about 700-750Kg when you go for IVA.

And I still not convinced yet that the Rover radiator will be up for the job. Will only know this once on the road and up to boost!

[nutter]

cheers,
I thought it was lighter than that.
Will see what happens with the rover radiator, its fine in the Civic type R kits, so should be ok with the VAG lump.

[limpabit]

Adam/nutter. Don't forget ehen you start, please do a build thread.

It helps other newbies as well.

Here's how mine started.

http://www.kitcar.good-hosting.co.uk/

[nutter]

Will do..
I also have a section on my website, which i will put more informatin on.
http://www.stsa.co.uk/content/projectEXi/
Not much there yet, but it will grow
Cheers
Steve

[5exiAdam]

THats more than ive got!

[alackofspeed]

Originally Posted by limpabit

And I still not convinced yet that the Rover radiator will be up for the job. Will only know this once on the road and up to boost!

For reference, in a 270bhp 1.8t front engined application, my friend has no bother with a 625x302x32 radiator.

That's with the standard oil/water cooler, which incidentally isn't too bad at keeping the oil temp down on track.

A K03s 1.8t running circa 230bhp, in a 700kg car will not be slow! On track I suspect more time would be found by increasing cornering speeds, and braking stability, than an extra 200bhp.

[limpabit]

If your looking for big power, have a word with Jabbasports or backdraft motorsport.

[5exiAdam]

Originally Posted by alackofspeed

For reference, in a 270bhp 1.8t front engined application, my friend has no bother with a 625x302x32 radiator.

That's with the standard oil/water cooler, which incidentally isn't too bad at keeping the oil temp down on track.

A K03s 1.8t running circa 230bhp, in a 700kg car will not be slow! On track I suspect more time would be found by increasing cornering speeds, and braking stability, than an extra 200bhp.

Mark Matthews reckons their tt engined track car is running 275bhp. Theirs is the BAM code engine with standard internals and just a map for the extra power.

A client of mine also races in the special GTs at castle combe with his EVO running up to 680bhp on racefuel. If i go into the special GTs myself, i would like to kick his backside!

The caterhams and alike seem to kill off the 5EXIs at combe. They seem to have the edge down the straights.

Last time i was up there, the 5EXIs seemed to be running 1min18s laps, which is pretty quick, but i would have expected more. There was a Seat Leon 1.8t that seemed to be running quicker laps than our chosen lightweight rockets.

[5exiAdam]

Originally Posted by limpabit

If your looking for big power, have a word with Jabbasports or backdraft motorsport.

Quite happy to have a shot myself!

Please ignore that quote when thinking of Famous Last Words remarks to sling in my direction.

[alackofspeed]

Originally Posted by 5exiAdam

Last time i was up there, the 5EXIs seemed to be running 1min18s laps, which is pretty quick, but i would have expected more.

It's the suspension geometry, and confidence the driver has to lean on the car. I'm far from an experienced track driver, but the way on an airfield day I could gain on a cut slick equiped "standard" Marlin through corners, when I was running Toyo road tyres, was all the evidence I needed to justify my mods to myself.

If you are serious about running high power, the first place to start on your quest to fast track car, is to put the power to one side for now, and concentrate on the chassis dynamics - some triangulation wouldn't go amiss, along with some mods to pick-ups, suspension arms, and rack re-location.

A K04 turbo can manage about 270bhp before it runs out of puff, so Mark's claim seems fair. Do you know what management they're using?