Dougie
27th January 2006, 04:53 PM
Ladies and Gents following lots and lots of confusion regarding differences in engines, components and models etc.
The below may cause more or answer some questions......
ENJOY
Easy one first. The Astra/Zafira VXR is a hybrid turbo that is different to the VXR 220 hybrid turbo. The VXR220 was used in development but the production version was changed. If someone is offering ‘VXR turbos’ then they are probably a hybrid design as per VXR220 , its possible they are the Astra/Zafira ones as they are now part numbered and available , but I didn’t think any parts were available yet.
Lotus development in Astra G. Lotus spent 10 weeks developing the base Astra 1.6 and a further period consulting on the other engine/suspension packages. 90% of the work was on the base car from which we developed the various set ups dependent on engine and trim. They did no specific work on the GSi set up , this was developed by OPC in Germany.
Lotus development in Astra H. Lotus were consultants on the base car and were involved in damper tuning only. The main work was done by a guy called Michael Harder at Opel and he involved Lotus only for some specific damper fine tuning. The H chassis is much more tuneable than the G and Michael developed a matrix of front/ rear spring rates , damper tuning and axle stiffness. It was in this development phase that we , Vauxhall, asked Gavan Kershaw at Lotus to tune the passive VXR chassis. Michael would do the active CDC chassis off those spring rates.
So did Lotus do work on the G? Yes , a lot , and the 1.6 is still rated as one of the best cars we’ve ever had. Did they do anything on the sports versions ? Yes they were consulted on damper/spring rates etc but the main work was Opels.
Did Lotus do work on the H? Yes they helped with the base car tuning. Did they do anything on the sports versions? Yes they helped set the groundwork for the Opel team to work from on damper rates.
Did Lotus do work on the VXR? Yes the passive chassis is a Lotus set up and differs vastly from the regular sports chassis.
Is the VXR chassis more aggressive than the Sri? Yes in every area. Chassis is 15mm lower , front anti roll bar bigger , rebound springs added to front dampers to control roll , new front uprights and steering knuckle raised roll centre up by 30mm. Spring and damper rates increased by 40 and 50%. Rear axle is unique to VXR and effectively invokes oversteer.
Net result is the car steers and pivots ‘sky hook’ style. Is more composed over bumps and delivers a more direct steering feel.
Technically apart from the pick up points for the suspension being the same everything else is different.
The Opel engineering team have done a great job on all the chassis’s for Astra and Lotus was used for UK tuning because of our roads that bear no resemblance to anything in Europe (except maybe Belgium) .
Does that make the Sri a bad chassis and the VXR a better chassis. Nope it makes the VXR a more aggressive chassis compared to the Sri , that’s all.
The below may cause more or answer some questions......
ENJOY
Easy one first. The Astra/Zafira VXR is a hybrid turbo that is different to the VXR 220 hybrid turbo. The VXR220 was used in development but the production version was changed. If someone is offering ‘VXR turbos’ then they are probably a hybrid design as per VXR220 , its possible they are the Astra/Zafira ones as they are now part numbered and available , but I didn’t think any parts were available yet.
Lotus development in Astra G. Lotus spent 10 weeks developing the base Astra 1.6 and a further period consulting on the other engine/suspension packages. 90% of the work was on the base car from which we developed the various set ups dependent on engine and trim. They did no specific work on the GSi set up , this was developed by OPC in Germany.
Lotus development in Astra H. Lotus were consultants on the base car and were involved in damper tuning only. The main work was done by a guy called Michael Harder at Opel and he involved Lotus only for some specific damper fine tuning. The H chassis is much more tuneable than the G and Michael developed a matrix of front/ rear spring rates , damper tuning and axle stiffness. It was in this development phase that we , Vauxhall, asked Gavan Kershaw at Lotus to tune the passive VXR chassis. Michael would do the active CDC chassis off those spring rates.
So did Lotus do work on the G? Yes , a lot , and the 1.6 is still rated as one of the best cars we’ve ever had. Did they do anything on the sports versions ? Yes they were consulted on damper/spring rates etc but the main work was Opels.
Did Lotus do work on the H? Yes they helped with the base car tuning. Did they do anything on the sports versions? Yes they helped set the groundwork for the Opel team to work from on damper rates.
Did Lotus do work on the VXR? Yes the passive chassis is a Lotus set up and differs vastly from the regular sports chassis.
Is the VXR chassis more aggressive than the Sri? Yes in every area. Chassis is 15mm lower , front anti roll bar bigger , rebound springs added to front dampers to control roll , new front uprights and steering knuckle raised roll centre up by 30mm. Spring and damper rates increased by 40 and 50%. Rear axle is unique to VXR and effectively invokes oversteer.
Net result is the car steers and pivots ‘sky hook’ style. Is more composed over bumps and delivers a more direct steering feel.
Technically apart from the pick up points for the suspension being the same everything else is different.
The Opel engineering team have done a great job on all the chassis’s for Astra and Lotus was used for UK tuning because of our roads that bear no resemblance to anything in Europe (except maybe Belgium) .
Does that make the Sri a bad chassis and the VXR a better chassis. Nope it makes the VXR a more aggressive chassis compared to the Sri , that’s all.