JonRB's Corrado VR6
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JonRB

Original Poster:

79,385 posts

295 months

Sunday 10th June 2007
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Had a good drive down to Weymouth and back yesterday including some excellent overtakes and some major commitment on some roundabouts that left me with a huge grin and the realisation that, although a stupid amount of money to spend on an old car, the £7k I've just spent on engine, brake and suspension modifications have left me with a real pocket rocket.

I was wondering how I could determine what the mods have done for the performance of the car and remembered the old CarTest software. I dug it out and, using the data from my Corrado Information site tweaked the simulation until I was getting the manufacturers figures for an unmodified Corrado VR6. Thus, having got a baseline, I then applied the changes I've had to the car using data from the DynoPlot and the new final drive ratio of 3.68:1

(Yes, I know, this is too geeky)

Anyway, the figures were surprising. The 0-60 of my car drops from 6.5s to 5.6s and the standing quarter drops from 15.2s @ 93mph to 14s @ 101 mph

I'm quite pleased with that. smile

EmmaP

11,758 posts

262 months

Sunday 10th June 2007
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Who's a lucky boy then? I'm very envious. Enjoy thumbup

neil_bolton

17,113 posts

287 months

Monday 11th June 2007
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Crikey! 230bhp from the ickle old VW VR6 - nice thumbup

I'd love to have a run against yours - so say I'm running similar power in the 328 due to some tinkerage that we've sussed out - mine certainly shouldn't be annoying 400bhp cars quite the way it does.

I'm sure the two would be very similar point to point biggrin

JonRB

Original Poster:

79,385 posts

295 months

Monday 11th June 2007
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neil_bolton said:
Crikey! 230bhp from the ickle old VW VR6 - nice thumbup
If I'd gone down the supercharger route I could have had 275bhp, and I believe Kev Hayward's 3.0L Turbo VR6 (ie. bored out from the standard 2.9L) is pushing out well over 300bhp.

But, yes, 230bhp is nice and the VGI really gives a good thump of extra torque in the midrange, just where you want it.
Peak torque is now 201 lb-ft at 3700 rpm compared with the stock 181 lb-ft at 4200 rpm.

Edited by JonRB on Monday 11th June 10:57

neil_bolton

17,113 posts

287 months

Monday 11th June 2007
quotequote all
JonRB said:
neil_bolton said:
Crikey! 230bhp from the ickle old VW VR6 - nice thumbup
If I'd gone down the supercharger route I could have had 275bhp, and I believe Kev Hayward's 3.0L Turbo VR6 (ie. bored out from the standard 2.9L) is pushing out well over 300bhp.

But, yes, 230bhp is nice and the VGI really gives a good thump of extra torque in the midrange, just where you want it.
Peak torque is now 201 lb-ft at 3700 rpm compared with the stock 181 lb-ft at 4200 rpm.

Edited by JonRB on Monday 11th June 10:57
The 328 spits out 206 lb/ft as standard (its restricted at factory to 192bhp) and weighs 1395 kg...

So going on the fact that the Corrado is 1240 kg - I'd hazard I'd be studying your ever decreasing numberplate in a straight run - unless the tinkerage has upped my lb/ft...(need to dyno it really).

speedtwelve

3,534 posts

296 months

Wednesday 20th June 2007
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Cool! Wasn't aware of CarTest...

Plugged the figures for my Corrado (216 bhp/200 lb ft) in and came up with:

0-60 in 5.7 secs

0-100 in 15.0 secs

1/4 mile in 14.5 @ 98 mph

Hmmm... Those Vortech & ZF superchargers do look appealing...

JonRB

Original Poster:

79,385 posts

295 months

Wednesday 20th June 2007
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speedtwelve said:
Plugged the figures for my Corrado...
When I was setting it up for the standard car I couldn't get the figures to come out right until I corrected the gear ratios (CarTest has the American SLC as standard) but also had to go into the advanced settings and start building a power and torque curve by giving it the power in 500rpm increments.
Did you do all that before getting your figures out?

speedtwelve

3,534 posts

296 months

Wednesday 20th June 2007
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Didn't touch the final drive figure as I assumed the SLC had the same final drive as the Euro VR6.

Didn't input power/torque at discrete rpm points either, just inputted the peak power & torque figures and relevant peak figure rpms from dyno plot.

Like yourself, Jon, I have a VGI fitted, which as you know considerably alters the torque plot compared to the standard car. I might sit down and input the figures as you have done when I have more time!

JonRB

Original Poster:

79,385 posts

295 months

Wednesday 20th June 2007
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You'll find the gearing and final drive data you need at www.corrado-vr6.info and your should be able to approximate the power at various revs from the DynoPlot you should have got when you had your mods done.

The SLC appears to have completely different gearing and final drive to the Euro-spec VR6. It also has the Golf's 2.8L VR6 engine and restricted throttle body rather than the Euro's 2.9L and bigger throttle body.

nerd

SuperchargedVR6

3,138 posts

243 months

Wednesday 20th June 2007
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Hi Jon,

Glad you're still enjoying the car. I was wondering how you were getting on with it after your track sessions.

Anyway, yep, we got over 300hp on the dyno session. The exhaust proved too restrictive and 8psi was all it could hold at the top end, but that was still enough for 324hp with 314lb/ft. More importantly, that torque is available from 2800rpm.

I've since added a 2.5" exhaust system which is currently not showing any signs of boost drop (Wastegate set to 11psi) at the top end, but I've yet to dyno it to confirm it's worked, in terms of hp gains.

It's certainly fun to drive and far from unmanagable :-)


neil_bolton said:
So going on the fact that the Corrado is 1240 kg - I'd hazard
They're actually a little porkier than that if my session on a public weighbridge is anything to go by. 1320Kg with a full tank (15 Gall) of gas.


EmmaP

11,758 posts

262 months

Thursday 21st June 2007
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SuperchargedVR6 said:
neil_bolton said:
So going on the fact that the Corrado is 1240 kg - I'd hazard
They're actually a little porkier than that if my session on a public weighbridge is anything to go by. 1320Kg with a full tank (15 Gall) of gas.
I thought they were much heavier. I've just checked - unladen weight 1210kgs, gross vehicle weight 1580kgs.

900T-R

20,406 posts

280 months

Thursday 21st June 2007
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SuperchargedVR6 said:
They're actually a little porkier than that if my session on a public weighbridge is anything to go by. 1320Kg with a full tank (15 Gall) of gas.
That's including the aftermarket forced induction gubbins? smile

neil_bolton

17,113 posts

287 months

Thursday 21st June 2007
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EmmaP said:
SuperchargedVR6 said:
neil_bolton said:
So going on the fact that the Corrado is 1240 kg - I'd hazard
They're actually a little porkier than that if my session on a public weighbridge is anything to go by. 1320Kg with a full tank (15 Gall) of gas.
I thought they were much heavier. I've just checked - unladen weight 1210kgs, gross vehicle weight 1580kgs.
Hmm, I could never figure out which weights to use: Anyone fancy finding out what the gross vehicle weight is for the 328i Sport?

BTW - I found out yesterday that I haven't got the manifold and throttle body conversion for mine - but we were scratching our heads as to why I can rev so high - and that only means a remap.

Which means that with a £400 mod; 325i inlet manifold and throttle body, I can hopefully get even more power evil

Jon, I'll be after you hehe

Edited by neil_bolton on Thursday 21st June 15:46

JonRB

Original Poster:

79,385 posts

295 months

Thursday 21st June 2007
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neil_bolton said:
Jon, I'll be after you hehe
I'll just move the goalposts again. wink

Chimune

4,028 posts

246 months

Wednesday 4th July 2007
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Jon, did you go for the Gaz suspension in the end? I need new suspension on both the raddo and the chim and i am thinking i may get a saving by putting Gaz on both ! Any thoughts ?

JonRB

Original Poster:

79,385 posts

295 months

Wednesday 4th July 2007
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Chimune said:
Jon, did you go for the Gaz suspension in the end? I need new suspension on both the raddo and the chim and i am thinking i may get a saving by putting Gaz on both ! Any thoughts ?
Yes, I did go for the GAZ. However, mine is only the second Corrado to be so fitted and the first with the standard top mounts, which required some custom fabrication of aluminium spacers. So it's not an off-the-shelf kit as such.

I've also found the springs I specified to be a bit soft and am waiting on Derek "the gazman" Gardiner of Absolutely Shocks to send me out stiffer replacements - something he's offered to do for simply the cost of postage, which is very nice of him.

To be honest, the Koni top-adjustable Sports Dampers and H&R springs that I had on the Corrado before were very good and much, much cheaper (like less than half the price). If I was making a recommendation then I would suggest looking at them as they are completely off-the-shelf and are proven and well understood by many tuners.
However, the GAZ setup is massively more adjustable - even a couple of clicks on the front dampers make big differences to stiffness and ride, whilst with the Konis there wasn't a huge amount of difference between full soft and full hard.

As you say, though, you may be able to get a good deal by buying two sets so maybe worth considering.

Edited by JonRB on Wednesday 4th July 16:11

Chimune

4,028 posts

246 months

Wednesday 4th July 2007
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Ah - i didnt realise a set was being tweeked specialy for you. It will be interesting to see what Absolutely say, as i emailed today asking for a quote an a similar setup. He may decide its not worth the hassle !

I am defo tempted by the H&R / Koni setup, plus there is an FK gb on the forum.

I am just tight and looking for a bargain !

BTW - someone is asking about GAZ on the suspension thread there too.

JonRB

Original Poster:

79,385 posts

295 months

Wednesday 4th July 2007
quotequote all
Chimune said:
BTW - someone is asking about GAZ on the suspension thread there too.
Can you give me the link, please, and I'll pop on and contribute.

Chimune

4,028 posts

246 months

Thursday 5th July 2007
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JonRB

Original Poster:

79,385 posts

295 months

Thursday 5th July 2007
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My Corrado is currently at a local indie with a failed radiator at the moment. frown

Not only did it have an actual leak in the front of the rad which was jetting out in a small stream, which I managed to plug with metal putty, but also coming out of the back of it where I couldn't access it. So new rad then.

Also due towards the end of the month with my more regular indie is changing over the front springs, an ECU remap to defeat the internal immobiliser (it occasionally kills the engine on startup) and also the fitment of an oil cooler. The latter is needed as I was seeing 140 degC oil temperatures on track at Thruxton a couple of months ago! eek

I've got a Castle Combe track day in August and think an oil cooler before then might be a good idea.

Edited by JonRB on Thursday 5th July 14:19