122 replies to this topic

[Phear]

An unmolested N/A should be quicker in a straight line than a Mini or R26R, in the corners it wouldn't even be a contest. Totally different cars, one is a purpose built sports car, the other 2 are just tweaked hatchbacks. Only the extremely light or extremely expensive get close to a S/C VX

Edited by Phear, 09 May 2010 - 05:45 PM.

[Sutol]

The NA to me was under powered. On overtaking it was worrying on occasions as to whether i was going to get past the stuff i was overtaking. With the SC fitted no problems anymore. Also don't even have to drop a cog, it makes driving the car a lot less frantic if you want to drive fast. On track at Goodwood it made 20mph difference in speed down the Lavant straight, ie NA 110mph, SC 130mph before braking. Handling wise, feels the same as my NA but I don't chuck it into corners like some of you guys do. Never driven a tubby in earnest so can't comment there. Cheers Chris

[garyk220]

But the opinion seems to favour the s/c route because of the n/a handling, and weight saving. All is becoming clearer.

The weight saving is not as great as quoted by some here. Official figures at release were NA 875kg and VXT 925gk. Throw in the chargecooling on a Stage 2 SC and the SC NA is probably a shade under 900kg - so only 25-30kg difference to a Stage 2 VXT.

And in my opinion the extra weight over the rear wheels improves the weight distribution and traction on track. Both cars suit very different driving styles. I've been in very quickly driven NA and SC cars and on the limit through faster bends they will push to understeer and are very easy to hold at the limit. The VXT tends towards oversteers on the limit on a balanced throttle and on some tracks makes for a quicker line and exit through bends. I've seen one of the Vauxhall press VXTs do sub 60 second laps chasing down and passing a factory GT3RS in the hands of an experienced Scottish racing driver and the only reason those times are possible is with the rear of the car steering a slightly wider line than the front. Understeer cripples lap times at a circuit like Knockhill.

Depends very much which driving style you prefer. I had both cars a few years back (almost exactly 7 years ago thinking about it) and chose to sell my NA and modify my turbo due to the on-limit handling characteristics. No amount of money thrown at my NA would have given the same effect.

PS. with a rear wing and around 860kg kerb weight my car was more than a match for SC Exiges round Knockhill. Faster into the bend, through the apex and more quickly onto the power.

Definitely horses for courses and well worth trying both on track for an extended period of time if at all possible before making an informed decision.

Edited by garyk220, 09 May 2010 - 06:06 PM.

[jonnyboy]

Well after a pretty decent run in mine again today I can only praise it. It's devestatngly quick. On a typical B road I don't think there's many cars would pull away from you. My car is always going to be road biased with the standard suspension but my god they will make an awesome track car with the right bits on. I've been in a R26R round cadwell park and it was quick. They are really decent bits of kit but they don't have back seats and you can't retrofit back seats. Given that they are FWD and nearly 20 grand it's very diffcult to justify one unless you want to go very fast round a track without needing to be the best driver in the world. Round most tracks I would think they would be a tiny bit quicker than a standard NA simply because they are so point and squirt. Someone who really knew what they were doing could probably embaress one easy enough. The SC just puts it in a different league though I'm not surprised to hear of Joes doing so well. As for the Exiges what kerb weight are they? The standard S wouldn't be as quick as a stg 2 SC would it?

[rob999]

I think these SC'd N/A's are becoming two a penny by the sounds of it!

[Phear]

Yeah there must be like 30 out there now Still more exclusive than a McLaren F1 or Alfa 8c

[Exmantaa]

The weight saving is not as great as quoted by some here. Official figures at release were NA 875kg and VXT 925gk. Throw in the chargecooling on a Stage 2 SC and the SC NA is probably a shade under 900kg - so only 25-30kg difference to a Stage 2 VXT.

My standard NA is not the lightest. Modded only with a stage II SC, a PA chargecooler system plus the Piper mani, 2,5" cat and the turbo backbox it all came to 902 kg. (With ~1/2 tank of fuel.)
Still pretty quick though...

But I think the the added SC weight high up to the engine is not very beneficial for handling. Still thinking how to lower the CofG at the rearend. (Reposition SC with new manifold, tilt and lower the Engine, etc etc... )

[jonnyboy]

I was worried about the additional weight but you cant tell any difference. I like to think I'm pretty tuned in to changes in the handling and for my money its not noticeable. If you did a stage 4 tubby you'd be adding a similar amount of weight.

[VXT Tim]

If you did a stage 4 tubby you'd be adding a similar amount of weight.

? Won't it just be the cc setup that is the similar weight addition. Nothing else on the T.

How much does the actual s/c weigh, any difference between the conventional gm (who is the maker btw) and a harrop?

[Phear]

Standard GM supercharger is an Eaton M62. I don't know exact weight (I believe Seb may have weighed it) and I can't find it online but I would estimate 7-8 kilos for the charger and another 3-4 for the inlet manifold.

[pickle]

Sounds to me like the supercharger may actually make the N/A a better day to day proposition, lots of lovely torque to make the world go.

How well does it suit the standard gearbox? Someone mentioned the Zafira (6 sp?) box, is this a simple option?

My car is used 99.9% of the time on the road and unfortunately mpg and insurance will impact upon whether I go down S/C or tuned VXT route. Has anyone got experience of these rather more mundane factors?

I've got to say, from what I've heard I'm leaning toward the S/C. I like the idea of my car growing with me. As I slowly sort the little niggles, improve and modify, learn it's character, and most importantly improve my driving I can change my car to challenge me more. It would seem unfaithful to ditch her for a younger model with a firey temprement and enhanced (power) curves....

[Winstar]

Sounds to me like the supercharger may actually make the N/A a better day to day proposition, lots of lovely torque to make the world go.

How well does it suit the standard gearbox? Someone mentioned the Zafira (6 sp?) box, is this a simple option?

No it's the Zaf 5 speed that has a 4.17 final drive to make the gear ratio shorter to account for the increased rev limit, std box is better for a day to day car.

You could get a 6spd from a z22yh engine, but you'll all so need drive shafts from a europa and gear cables £££

[Phear]

MPG isn't much worse unless you are constantly giving it some stick. Insurance however is another issue. I actually didn't end up paying much more but your options are much more limited when your trying to insure a modified car, particularly a heavily modified one. Gearbox is good, 6 speed would be nice for motorway driving tho but its £2k+ upgrade once you factor in drive shafts etc.

[The Batman]

insurance was extra £300 for a 21 year old

[Mangham54]

insurance was extra £300 for a 21 year old

p*ss off you bastard...

It was going to cost me more than that just to change wheels OR fit an ITG when I was being quoted recently and I am 26yo!

[soupdragon]

or a vxr astra

pure torque steering rubbishness

Are you speaking from experience or just from the top gear test of pre production cars?

I had an Astra H turbo SRI (5dr) for 4 years and torque steer never was an issue.
As a road car it was one of the best I've owned and I've owned a lot of cars!

It also has me convinced that the 6spd is the way to go for my VX
The ratios are better spaced and the taller 6th will make it more practical on longer runs
i.e. Quieter and better range from the 36 litres

[pickle]

Extra £300 for the insurance and similar mpg. What's not to like? £2k for a 6sp box puts it firmly in the territory of mods to do when all else is done, but it does appeal to me. Used to have a 6sp in my old R26 with 6th gear being in the same place as reverse is now. Could be nasty in an absent minded moment.....

[Seb.F]

Yep, Joe speaks the truth, my insurance went up £400 and I'm 21 too. But that was from standard VX to: Gaz Suspension TD 1.2 Wheels Supercharger Milltek Exhaust

[fred666]

Seb do you know Dan Savage by any chance? He mentioned a mate with a supercharged VX named Seb, must be you lol

[Seb.F]

Mr vanman I do indeed With the 206SW?