Built not bought: Getting a grip
Posted on April 29, 2014 | By Editor | Leave a response
Ollie’s had chance to reflect on the modifications to the ZS’ gearbox and is feeling rather pleased about the improvements it’s made to his car…
Words & pictures: Ollie Kirk
Its been two weeks now since I received my gearbox back from Grant at GBE. Excellent service and price again.
The gearbox has had steel caged bearings fitted and needed a fair bit of work to get within tolerances on the end float and gear lash.
Whilst this was being taken care of a Gripper Limited Slip Differential (LSD) has been fitted.
I have a lightweight flywheel fitted from TTV racing, bought through EKSpower of the xpower forum.
Heres the Gripper, it doesn’t look much!
This is the lightweight flywheel. I’ve weighed it at 4.6kg! When I weighed the standard it was 9.6kg a 5kg reduction!
Thoughts on the new bits:
Initial impressions were that the gearbox has a very solid feel to it, next to no excess movement in the gear linkage and it all feels very taught and strong. I noticed the lightened flywheel straight away on first up! As the car starts the revs rise and settle to its engine idle speed, this has always had a relaxed feel to it. With the lightened flywheel this settling is almost instantaneous!
I’ve now been driving the car for 2 weeks and it really is different now, a vastly improved car!
I’ll start with the lightened flywheel. I had read a lot of opinions on the internet regarding the fitting of a lightweight flywheel, issues like problems idling, needing more revs when pulling off and lots of people believing the car would struggle up hills!
In my experience, all of the above is rubbish! I’ve found no ill effects of fitting this, the car idles exactly the same as it did with the standard flywheel, I need no extra revs pulling off and it certainly doesn’t struggle up hills!
The car has been improved no end, the engine is more responsive, more immediate throughout the rev range.
I have found the VIS is a lot more responsive now as well. After what I have read regarding the lightweight flywheel benefiting the early gears more than the higher I have really been impressed with the difference in fifth gear! I really noticed this on the motorway, cruising in fifth at around 2750rpm at 60ish mph I can apply more throttle and the engine instantly picks up revs then the VIS comes in at around 3000rpm and away I go. Very impressive. In this scenario speed increase has become very deceptive!
The overall improvement was again proved to me the other day when I had chance to take the car through the gears, it really did feel relentless! From low revs in second to the top of fourth gear it was just unyielding in the power delivery and the effect of the lightened flywheel makes the rush to the redline so much more urgent, its actually a little too easy to run in to the limiter until you are used to the new urgency. I thoroughly recommend one!
Now the Gripper diff – this is even more impressive!
I originally was considering the Quaife ATB differential. After speaking to Grant I decided to go with the Gripper due to it being a stronger unit, superior in performance being a ‘plate’ type and unusually for a ‘plate’ diff very progressive. This was a pre-requisite for me as anything less would be at odds with ZS’s nature, for this reason I originally considered the Quaife but Grant assured me of the Gripper’s superior qualities.
He was right, the gripper suits the cars character completely. What I have found is that on initial entry and beginning of the corner i’m using the cars natural grip. As I apply throttle I can feel the diff ‘come in’ and the grip levels go through the roof but none of this detracts from the car or is over-riding it’s natural handling characteristics. It is smooth and enhances what I have at my disposal.
I have also been suitably impressed with the traction on wet or dirty roads. I recently turned on to a wet road covered in mud whilst in second gear, I applied full throttle from around 2500rpm up to 6500rpm and there was no wheelspin, no tugging of the wheel just relentless acceleration. I thought to myself this is normally the preserve of your Scoobs etc and what their owners rave about. This excellent new attribute was again proved the other night when pulling out onto a road where I had to get out quickly, I had to launch and accelerate reasonably hard in first and again no wheel spin, it just bolted!
The Gripper is, I believe, a rally spec diff. This is backed up by some of the noises it makes. I don’t mind this as the performance increase is well worth it. Sometimes when accelerating the diff can make a whine which is akin to a supercharger! Some low speed noise does sound like i’m dragging something under the car!
I am hugely impressed with all the bits fitted and I am even more excited about the next chapter! Keep watching everyone!