Parr or JZM - Guidance Sought Please
Discussion
I know this has been discussed before and I am aware that people tend to sit in different camps here, but in the new year I am going to embark on some minor mods to my Mk2 GT3 starting with a suspension set up. My mix is probably 90% road and 10% track at this time so I am much more interested on improving its road manners first and then maybe moving to some more track focus as I get used to the car. Start small, understand the impact, then develop and evolve it is my plan.
I have spoken to Parr and to JZM who seem to be the recognised players in the UK when it comes to GT3 work and now I have to choose which route to take. I am sure both will be excellent but I would appreciate peoples comments, ideally those who have worked with both. I am happy to take emails on this (via profile) if people don't wish to go public and I am looking for constructive input and would love to know how they differ?
I emphasise at this time I am not looking to start swapping bits, that will come, but first off I am looking at improving the stock set up by dialling out understeer and improving initial turn in feel. Thanks in advance!
I have spoken to Parr and to JZM who seem to be the recognised players in the UK when it comes to GT3 work and now I have to choose which route to take. I am sure both will be excellent but I would appreciate peoples comments, ideally those who have worked with both. I am happy to take emails on this (via profile) if people don't wish to go public and I am looking for constructive input and would love to know how they differ?
I emphasise at this time I am not looking to start swapping bits, that will come, but first off I am looking at improving the stock set up by dialling out understeer and improving initial turn in feel. Thanks in advance!
Good, I'd also be interested in hearing GT3 owners experience of factory settings vs Parr/JZM set-ups for the road.
I'll be taking my Mk2 in for OPC service soon and as a matter of course, was going to ask them to do a full geometry/alignment check at the same time. But from reading the glowing reviews of above specialists, maybe I'd be better getting the geo/etc check done there although they are 400 miles away.
I'll be taking my Mk2 in for OPC service soon and as a matter of course, was going to ask them to do a full geometry/alignment check at the same time. But from reading the glowing reviews of above specialists, maybe I'd be better getting the geo/etc check done there although they are 400 miles away.
batman69 said:
Sounds like your first change will simply be getting the geo changed for a bit of track work. Both Parr and JZM can do this very easily. The different routes will be if you choose to replace dampers etc then the discussion starts - in summary spend the money on driver training!
The "spend money on driver training" is often appropriate, though somewhat asumptive don't you think? I did my formal track driver training 22 years ago, and have been learning ever since, so pretty safe to assume I am now ready to move to the next level and make a few changes....
If picking suspension perhaps the pertinent question is how many with JRZ vs KW dampers trailer their cars to track. Will give an idea of the setups they were designed around. KW was setup around the ring, I think JRZs were setup by Steve around traditional circuits, so personally I'd consider that in my decision. They are all adjustable though, although I'm not sure in many ways.
I've ridden in Timbos JRZ setup car on the road and its pretty uncomfortable, but I'm sure its awesome on track. Unfortunately only been in a KW car at the ring where it felt very controlled. Doesn't really give me a basis for comparison though.
I've ridden in Timbos JRZ setup car on the road and its pretty uncomfortable, but I'm sure its awesome on track. Unfortunately only been in a KW car at the ring where it felt very controlled. Doesn't really give me a basis for comparison though.
Edited by DanH on Friday 8th December 12:49
Thanks Dan, but as I was saying I am looking to keep it standard for now, not change components (that may well come later). I appreciate the limitations of this approach, but phase 1 for me is to get the stock set up improved for road use. I hoon a lot you see, so being able to drive into the Alps and enjoy the car to its maximum on the road is where I am at right now.
housemaster said:
Thanks Dan, but as I was saying I am looking to keep it standard for now, not change components (that may well come later). I appreciate the limitations of this approach, but phase 1 for me is to get the stock set up improved for road use. I hoon a lot you see, so being able to drive into the Alps and enjoy the car to its maximum on the road is where I am at right now.
Well in that case pick who you want. The only factor to consider is that the Parr setup widens the front track with spacers, but that will require your wheel arches to be rolled. Personally I was keen not to mess so went to JZ.
DanH said:
Well in that case pick who you want. The only factor to consider is that the Parr setup widens the front track with spacers, but that will require your wheel arches to be rolled. Personally I was keen not to mess so went to JZ.
Ah, now we are getting there. What I want is input on how they differ and finally I am getting that. Thanks again Dan. I appreciate there a loads of you who want to change all sorts, and in time that will come, but right now I am working on a KISS basis....
I've used JZM on two 964 RSs, my MK1 GT3 (and my GT2 is booked in with them the week after next)
They ain't the cheapest, but they're professional, know what they're are doing, and most importantly, they're communicative.
Having dealt with some other so called specialist indies (who couldn't even be arsed to pick up the phone to discuss issues) the last point counts for a lot IMO
I've only dealt with Parrs once when I owned a 993 RS (and felt they were overpriced)though I have no complaints with the level of service they gave.
Parrs geographically, were/are the wrong side of the Smoke for me as well.
They ain't the cheapest, but they're professional, know what they're are doing, and most importantly, they're communicative.
Having dealt with some other so called specialist indies (who couldn't even be arsed to pick up the phone to discuss issues) the last point counts for a lot IMO
I've only dealt with Parrs once when I owned a 993 RS (and felt they were overpriced)though I have no complaints with the level of service they gave.
Parrs geographically, were/are the wrong side of the Smoke for me as well.
Same here, I live in the Midlands so Parr's are a right treck for me too. JZM have been very good on the communication front in my experience and so have Parr's so I can't differenciate either on that front. JZM is looking favourite right now simply due to location and the fact that both seem able to deliver in the area I am looking.
I have a Parr 'fast road' geometry setup on my Mk1 and can thoroughly recommend both them and the improvements to handling. 
I also use Parr for servicing and have found them to be superbly efficient, responsive and only too happy to spend time discussing exactly what you want done to the car.
In my case geography was the deciding factor in my decision to go to Parr, but I was equally impressed after my discussions with JZM (although I don't have any direct experience of their work).
I also use Parr for servicing and have found them to be superbly efficient, responsive and only too happy to spend time discussing exactly what you want done to the car.
In my case geography was the deciding factor in my decision to go to Parr, but I was equally impressed after my discussions with JZM (although I don't have any direct experience of their work).
housemaster said:
jeremyc said:
I have a Parr 'fast road' geometry setup on my Mk1 and can thoroughly recommend both them and the improvements to handling.
Jeremy, where are the changes most obvious. Turn in, dialling out understeer, reducing tram lining, better handling over the bumps??
HM, when I purchased my MK1 GT3 earlier in the year it was the most evil handling car I'd ever driven.
Totally inconsistent, sometimes it would turn in really crisply and clip apexes, other tmes you'd find yourself missing them by several feet.
It followed cambers and worn motorway tarmac like it had a mind of it's own.
All alleviated at a single stroke by JZM fast road setup. There is still a trace of stabilising understeer in the setup, but once you've driven through it the car is nice and neutral.
The MK2 GT3 I drove 3 months ago had the same tyres on as my car (Pirelli Rossos) and I found the front end vague and remote in comparison with my MK1 version.
It was fine once you'd made the leap of faith and driven through the initial understeer (but not something I 'd want to do at really high speed)
This initail understeer was picked up by most of the journalists who drove the MK2 and led them to mark it down for having steering that was less pointy than the MK1.
I think (DanH may be able to confirm) the GT3 RS addressed the problem by using different front hub carriers/bearings which allowed better geometry for improved turn in.
Thanks slippy, excellent feedback and really where I am at now. It needs to be taken to the next level and needs to have the Porsche 'safeness' (I am being polite!) dialled out. Your summary of the driving experience is spot on and reflects what I am finding. Still love it, but I am well aware it can be improved hence this post really.
housemaster - I was where you were a year ago.
My GT3RS was bloody awful. Understeering everywhere, horrendously light at the back end on the brakes, following cambers, no weight in steering, no traction at the back (I blame Porsche Reading who unsuccessfully tried to revert to standard a previous "track-only" setup - idiots left my car handling disgracefully).
I went to Parr for their stage 1 geo - my impressions:
- Front end - no longer wooly - razor sharp
- Understeer finished (get the weight over the front and it's TOTALLY gone).
- Rear stabilised with increased traction.
- NOT following cambers anything like as badly (but still follows them though)
Car will be back at Parr having new tyres and being geo-ed again.
Having spoken to JZM, I think the Parr stage 1 is racier than the JZM stage 1 which is more benign and "roady": All of the following are things my RS does with it's Parr 1 that the guys at JZM said their stage 1 would NOT do:
The insides of my rears were slicked whereas JZM said their setup wouldn't do this. (more camber applied by parr than jzm?)
The car is still quite tiring at high speed on m-way as front end really is switched on.
Car is UNBELIEVABLY useless over speed bumps - rides LOW. (remember this is a road setup)
Needed arches rolled (don't care about this as car is so low it looks fantastic).
This year I was thinkin about sending it to JZM for THEIR stage 1 but do not want any of sharpness Parr injected potentially taken out (or for it to sit any higher). So it'll be back to Crawley.
Will probably get the JZM Alcons for brakes instead of the Parr brembos - don't do enough trackwork for the Parr items to be justifiable especially with the rattling etc.
My GT3RS was bloody awful. Understeering everywhere, horrendously light at the back end on the brakes, following cambers, no weight in steering, no traction at the back (I blame Porsche Reading who unsuccessfully tried to revert to standard a previous "track-only" setup - idiots left my car handling disgracefully).
I went to Parr for their stage 1 geo - my impressions:
- Front end - no longer wooly - razor sharp
- Understeer finished (get the weight over the front and it's TOTALLY gone).
- Rear stabilised with increased traction.
- NOT following cambers anything like as badly (but still follows them though)
Car will be back at Parr having new tyres and being geo-ed again.
Having spoken to JZM, I think the Parr stage 1 is racier than the JZM stage 1 which is more benign and "roady": All of the following are things my RS does with it's Parr 1 that the guys at JZM said their stage 1 would NOT do:
The insides of my rears were slicked whereas JZM said their setup wouldn't do this. (more camber applied by parr than jzm?)
The car is still quite tiring at high speed on m-way as front end really is switched on.
Car is UNBELIEVABLY useless over speed bumps - rides LOW. (remember this is a road setup)
Needed arches rolled (don't care about this as car is so low it looks fantastic).
This year I was thinkin about sending it to JZM for THEIR stage 1 but do not want any of sharpness Parr injected potentially taken out (or for it to sit any higher). So it'll be back to Crawley.
Will probably get the JZM Alcons for brakes instead of the Parr brembos - don't do enough trackwork for the Parr items to be justifiable especially with the rattling etc.
Edited by murcielago_boy on Friday 8th December 14:44
I'm not overly keen on the RS look (white with red or blue) so seriously considered going the "standard" MK2 route and fitting RS front hubs/uprights to alleviate the understeer built in by Porsche for our "litigieous friends over the water"
That with an RS rear wing and a set of Manthey BBS wheels would have been my ultimate NA 996.
Something like this
Instead I went to the "darkside"
That with an RS rear wing and a set of Manthey BBS wheels would have been my ultimate NA 996.
Something like this
Instead I went to the "darkside"
Great stuff guys, excellent input and just the type of feeback I was looking for. Reducing the ride height much more is likely to be an issue for me as I can only just get in and out of my driveway, which is half a mile long (not all my land!) with a cattle grid at each end and a gradient, so reducing it too much more may give me issues.
Forgive my ignorance, but explain rolling the rims?
Forgive my ignorance, but explain rolling the rims?
They are both good. Parr ultimately has more motorsport knowledge than JZM (Parr are Porsche UK's works motorsport team so they should do) and will set up a car specifically to suit your requirements if you ask them, rather than giving you an either or tyre of choice.
The GT3 is infinitely adjustable, a good tuner can make it basically what you want it to do - providing you know exactly what it is you are looking for. The trick is to be realistic about your own abilities and know exactly what you want from the car. An extreme race set up generally needs a higher level of driver skill to harness than say a fast road set up which will be far more foregiving but ultimately slower and frustrating for the experienced driver.
I'd work out exactly what you wanted from the car on the road and track, write it down and call Paul Robe at Parr and he will work the set up around your requirements.
Steve R
The GT3 is infinitely adjustable, a good tuner can make it basically what you want it to do - providing you know exactly what it is you are looking for. The trick is to be realistic about your own abilities and know exactly what you want from the car. An extreme race set up generally needs a higher level of driver skill to harness than say a fast road set up which will be far more foregiving but ultimately slower and frustrating for the experienced driver.
I'd work out exactly what you wanted from the car on the road and track, write it down and call Paul Robe at Parr and he will work the set up around your requirements.
Steve R
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