59 replies to this topic

[Hopey]

Hi everyone, I'm currently at the very early stages of turning my lovely Coral Blue VXT (ex Mark Penny's car, for those who know the great man) into a bit of a project.  Current plan is to use Courtenay Sport for the engine/gearbox work and the fantastic Jez @ Back on Track for everything else.  Nev has graciously agreed to act as my "build guru" and has been a brilliant sounding board in helping me get this project off the ground. Nev suggested I start a project thread, so here I am.

 

The overall aim is to create my perfect second car (I have a Skoda Yeti as my sensible wheels).  It will be used for weekend blasts, occasional road trips (hoping to take it to Germany for a cousin's wedding and to Spa for the F1 GP this year) and as many track days as I can fit in.  I want the car to be as track-focussed as possible but without totally ruining it as a road car.  I need to be able to whisk the girlfriend off for the weekend without getting even more of an earful than usual!  General approach is to make sure that whatever work I have done is as good as it can be done - but I do want to try to make sure that costs don't spiral out of all control.

 

I have spoken to Courtenay (so far they have been very helpful indeed) and will be taking the car to them at the end of the month for them to start the engine build.  I had originally set myself a target of 400bhp, which would basically mean using a Garrett GTX28 turbo and new exhaust manifold for the build (along with all the other usual mods for these high power jobs).  Courtenay say they can do this no problem, but that they in fact would recommend going with a K06 turbo and limiting power to around 340bhp instead on the basis that the k06 build will deliver more power lower down the revs and kick in with less of a bang than the bigger Garrett, which would make it more drivable, especially on the track.  Would be interested to hear your thoughts on this, not least because they are quoting an extra £5k for the Garrett build over the K06 build!

 

Do people have a view on Garrett GTX28 vs K06 (particularly on the driveability question)?  Is a 340bhp VXT totally bonkers or would it leave you wanting 400bhp pretty soon?

 

Looking forward to sharing my project with you guys and thanks in advance for any help/advice!

 

Matt

 

 

[Acidpopstar]

Why don't you consider the Audi S3 engine conversion? Duncan VXR is the man to talk to. I've been in Crabash's and it's epic. Very smooth power delivery and an easy 375bhp for starters. Sent from my iPhone using Tapatalk

[Hopey]

I'd happily consider an S3 conversion (or any other conversion that people recommend).  What would be the advantage of going down that route rather than modifying the existing engine?

 

So far I've just not heard enough about conversions whereas Courtenay have a lot of experience tuning the Z20 LET.  There is also a part of me that like the idea of keeping the original engine, albeit heavily modified.

 

Wouldn't the cost/complexity of a conversion also be fairly substantial?

[CHILL Gone DUTCH]

I think the secret is finding the usable power And traditionally this has been a issue for most stage 4 turbo cars (300 bhp ) I've seen good results from standalone conversions.

Edited by CHILL Gone DUTCH, 06 March 2017 - 01:22 PM.

[siztenboots]

It is too easy to get target focussed on a certain bhp from a turbo , when sadly its all the other items that need consideration, 400bhp on standard suspension and brakes, cooling for the water, oil and air charge systems, custom exhaust/heat shielding/cats , gearbox rebuilds , special clutch cover and friction plates.

 

The level of power you mentioned is often referred to as the "Stage 5, or one stage too far"

 

If going for a stage 4/5 , then ideally buy one already done, that is proven to be trouble free.

 

Courtenay will quite happily spend your money on "motorsport" parts , but I think they are now about 7-8 years out of touch with the VX market, what works on a FWD 1500kg  astra is not suitable for RWD superlight track car.

 

[Acidpopstar]

I would pm Duncan and get him to talk you through the details of the Audi conversion then you can make a decision. If you wanted a cheap and way power boost Siztenboots on here has developed a 260bhp pack that gives you exactly that with a software tweak only. Also well worth contacting directly. Sent from my iPhone using Tapatalk

[Acidpopstar]

I would pm Duncan and get him to talk you through the details of the Audi conversion then you can make a decision. If you wanted a cheap and easy power boost Siztenboots on here has developed a 260bhp pack that gives you exactly that with a software tweak only. Also well worth contacting directly. Sent from my iPhone using Tapatalk

Edited by Acidpopstar, 06 March 2017 - 01:28 PM.

[Hopey]

Thanks very much for this.  Will drop them both a line.

 

I would pm Duncan and get him to talk you through the details of the Audi conversion then you can make a decision. If you wanted a cheap and easy power boost Siztenboots on here has developed a 260bhp pack that gives you exactly that with a software tweak only. Also well worth contacting directly. Sent from my iPhone using Tapatalk

 

[Rosssco]

If you're open to swapping the engine, also consider the A20NFT GM engine, as it would allow reuse of some of your existing parts, and has a number of advantages over a modified Z20 with a hybrid K06.. It's offer similar outputs as the above options, even more responsive, plus its a chunk lighter..

 

You could buy a brand new crate engine, loom, ecu and much of the other parts required for the price of a GT28 "upgrade"..

[Hopey]

Yes, fully agree with your comment re not focussing on a certain bhp and agree even more with your comments re the other items that need to be considered.  I see this a true project where I will be looking to ensure the car works well as a whole, so no part of the car will escape attention (there will be plenty more posts with plenty more questions to come on the other aspects of the build, fear not!).  However the first thing I want to sort out is the engine because that will then determine the parameters for the rest of the build as everything else will need to be designed around whatever power level I end up with.

 

I'm not looking to buy a car that is already at stage 4/5 because I want the fun/experience of doing my own build to my own specs - it's as much a learning experience for me as anything else.

 

Courtenay seem to have a good reputation and certainly have a lot of experience with these engines, although obviously more so in Astras etc than in VX's, but I would still guess they have had more experience with VX's than most other tuners (happy to be told otherwise if my guess is wrong!).  They have been very helpful so far and in fact have tried to talk me out of spending more money than I might otherwise have been prepared to do, which is a good sign.  I also like the fact that they offer a warranty with their engine builds, which shows that they stand behind their work at least.  Their suggestion, which I am very tempted by, is:

 

K06 turbo for around 340bhp

high flow inlet manifold

forged pistons, uprated steel rods, injectors etc

standard exhaust manifold but add full 3" Tullet exhaust system

keep original F23 gearbox but add Quaife LSD

new "organic" clutch

lighten flywheel

charge cooling system

Pro Alloy large capacity fuel tank

rolling road ECU mapping

 

I suspect that sort of power level would be plenty for me and would provide a great basis for the rest of the build.  But I have a nagging wonder whether, since I am going to the effort of getting the engine build done, I should go the whole hog and do a Garrett build.

 

 

 

its too easy to get target focussed on a certain bhp from a turbo , when sadly its all the other items that need consideration, 400bhp on standard suspension and brakes, cooling for the water, oil and air charge systems, custom exhaust/heat shielding/cats , gearbox rebuilds , special clutch cover and friction plates.

 

the level of power you mentioned is often referred to as the "Stage 5, or one stage too far"

 

I have just got off the phone to my Lotus/VX exhaust specialist about the next project to have a system that will get the higher power cars onto the tracks within the noise limits.

 

If going for a stage 4/5 , then ideally buy one already done, that is proven to be trouble free.

 

Courtenay will quite happily spend your money on "motorsport" parts , but I think they are now about 7-8 years out of touch with the VX market, what works on a FWD 1500kg  astra is not suitable for RWD superlight track car.

 

 

[Hopey]

If you're open to swapping the engine, also consider the A20NFT GM engine, as it would allow reuse of some of your existing parts, and has a number of advantages over a modified Z20 with a hybrid K06.. It's offer similar outputs as the above options, even more responsive, plus its a chunk lighter..

 

You could buy a brand new crate engine, loom, ecu and much of the other parts required for the price of a GT28 "upgrade"..

 

Interesting.  Could you tell me more - eg what are the key differences?  Where would you get a crate engine from?  Who would install it?  Thanks  

[siztenboots]

usually upgrades are done in the order of

 

1. make it stop

2. make it handle

3. add power / add lightness

 

you might consider adding traction control , or at least different wheels to allow wider semi slick tyres.

 

in terms of how bonkers you can get , I run about 400bhp per tonne, combination of getting weight down which also helps points 1 and 2

 

if you compare similar cars in the 400 - 500 range, http://www.autosnout...er-Ton-List.php , gives some idea

 

I am just doing a K04/06 hybrid build on mine (still standard engine) , so expect that to change to 440bhp per tonne , torque capped at 380.

 

[Duncan VXR]

http://www.vx220.org...art-transplant/ Steve thread ref the tfsi conversion I did http://www.vx220.org...urbo-met-black/ Have a look through one of the best ZLET big power builds Different beasts but both epic Tfsi is a newer more efficient and reliable engine that while the cost of conversion is there you have no need to open the engine or have to run custom engine parts Some prefer oem engine and having done just about most things to the vx would favour the vag setup (stronger box also) the standalone conversions I did address a lot of the stage 4 issues but it really depends what is wanted from the car As already stated do not over look decent suspension / brakes although you dp not have to go crazy 😊 plenty of great info on the site DG

[Rosssco]

 

If you're open to swapping the engine, also consider the A20NFT GM engine, as it would allow reuse of some of your existing parts, and has a number of advantages over a modified Z20 with a hybrid K06.. It's offer similar outputs as the above options, even more responsive, plus its a chunk lighter..   You could buy a brand new crate engine, loom, ecu and much of the other parts required for the price of a GT28 "upgrade"..

  Interesting.  Could you tell me more - eg what are the key differences?  Where would you get a crate engine from?  Who would install it?  Thanks

 

  Its the engine out of the current Astra VXR. Much more modern design with similar features to the VAG, but all alloy (related to the 2.2 NA engine in non-turbo VX's) allows you to run the engine standard without changing pistons etc etc.    http://www.courtenay...g/info_219.html   It's a 'bolt-in' conversion for the primary components, but like you'll still need custom parts like exhaust, chargecooler, and buy the ECU and loom from a German chap.   Here's him: http://www.vx220.org...ndalone-a20nft/

[tibby]

Eventually, a high tuned Z20let set up will break. (gearbox is the first thing when driving hard)  Best thing is, go for a high power build with OEM parts! +1 for the audi set up.

[Nev]

People talk about A20NFT and Audi engine conversions like they are something simple that a novice could do in a week. They are not. Even a pro engine converter working on such a project would take weeks and weeks (probably months) and there would be increased risk of parts failure, fitment/packaging issue, re-engineering things (like driveshafts), new bespoke fabrications (like exhausts, water pipes, air pipe routing). The list of extra complications (and hence risk + cost) is really huge. Most of all your new VX220 would be off the road and undrivable for ages, just when you'd want to be driving it!

 

Just looks at the project like the V6 projects ongoing (both 1+ year now), Dr Ed's A20NFT project (1+year and stalled) etc etc. Loads of them fail having spend thousands and thousands.

 

To a new owner, with no engineering experience I'd err on the side of caution myself and stick with the Vauxhall Z20LEx. In fact, that is what I did with my project.

Edited by Nev, 06 March 2017 - 04:12 PM.

[Hopey]

usually upgrades are done in the order of

 

1. make it stop

2. make it handle

3. add power / add lightness

 

you might consider adding traction control , or at least different wheels to allow wider semi slick tyres.

 

in terms of how bonkers you can get , I run about 400bhp per tonne, combination of getting weight down which also helps points 1 and 2

 

if you compare similar cars in the 400 - 500 range, http://www.autosnout...er-Ton-List.php , gives some idea

 

I am just doing a K04/06 hybrid build on mine (still standard engine) , so expect that to change to 440bhp per tonne , torque capped at 380.

 

 

Yup, as mentioned, will also be addressing the brakes and suspension etc and will be fitting different wheel sizes (and again, as mentioned, will be posting about those elements of the build in due course for help/advice gratefully received).  At the moment, I am just trying to get the engine right first.

 

Very interested in your K04/06 build.  You say you will be using the standard engine - is that a standard Z20 LET with no mods at all other than a new turbo?

 

 

[Hopey]

Yes, have to say that my preference would be to stick with modifying the original engine for these reasons.  Also I do like the authenticity of retaining the original engine with the car as well (call me sentimental...).  Certainly don't want the car to be off the road for the summer!

 

 

People talk about A20NFT and Audi engine conversions like they are something simple that a novice could do in a week. They are not. Even a pro engine converter working on such a project would take weeks and weeks (probably months) and there would be increased risk of parts failure, fitment/packaging issue, re-engineering things (like driveshafts), new bespoke fabrications (like exhausts, water pipes, air pipe routing). The list of extra complications (and hence risk + cost) is really huge. Most of all your new VX220 would be off the road and undrivable for ages, just when you'd want to be driving it!

 

Just looks at the project like the V6 projects ongoing (both 1+ year now), Dr Ed's A20NFT project (1+year and stalled) etc etc. Loads of them fail having spend thousands and thousands.

 

To a new owner, with no engineering experience I'd err on the side of caution myself. In fact, that is what I did with my project.

 

[Nev]

I'd say going down the CS route with the K06 would suit you fine in all likelihood. However, the only thing I'd strongly recommend is to get a 3rd party ECU which will be able to control the boost/torque far better. The only issue this might have is that if the engine blows up the mapper will blame CS and vice versa and it will likely be difficult to get it fixed under any waranttee.

 

 

Edited by Nev, 06 March 2017 - 04:18 PM.

[Duncan VXR]

People talk about A20NFT and Audi engine conversions like they are something simple that a novice could do in a week. They are not. Even a pro engine converter working on such a project would take weeks and weeks (probably months) and there would be increased risk of parts failure, fitment/packaging issue, re-engineering things (like driveshafts), new bespoke fabrications (like exhausts, water pipes, air pipe routing). The list of extra complications (and hence risk + cost) is really huge. Most of all your new VX220 would be off the road and undrivable for ages, just when you'd want to be driving it!   Just looks at the project like the V6 projects ongoing (both 1+ year now), Dr Ed's A20NFT project (1+year and stalled) etc etc. Loads of them fail having spend thousands and thousands.   To a new owner, with no engineering experience I'd err on the side of caution myself and stick with the Vauxhall Z20LEx. In fact, that is what I did with my project.

Fair points Nev and most would not or could not do this level of project Having all custom parts either in my garage pre machined or CAD drawn along with wiring diagrams, map etc with strong planning is about 3 weeks work 😊 DG