I just stuck 295/19/30s on my 987 with a 1" Spacer
05-24-2006, 02:29 PM
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I just stuck 295/19/30s on my 987 with a 1" Spacer
Talk about diminishing of the handling. I have a set of H&R Springs and Swaybars on my 987S. The rear swaybar is 2way adjustable and is set to soft. The front is non adjustable. The car feels mushy around sweeping turns at speed and the back end feels a bit as though it is going to break loose. So far I am having horrible luck with mods, exhaust, swaybar and springs.
I do like the look of the drop with the springs but there is nothing like stock, yet still I have the mod bug, why? Atleast I LOVE my B&M shortshift and Cayman Grills and think the GIAC is working well.
The rims look incredible. The forgelite 19x11 with a chrome lip and factory matched inner(stock fit for 997) I may get rid of the spacer and rebuild the 3piece wheels in the back with a shorter inner lip and 3.5 inch outer. Now that will be AWSOME. Reason I had to put an ADAPTER was because originally on the 997 Carrera S 19"s in Chrome sat too far inboard. I ended up using a 15mm spacer and I don't think that changed the handling. God I could push the car hard, and to the limit. The handlind was NEUTRAL, if it slid it was evenly, the car felt very stable at ANY speed.
What do you think, if I rebuild the rears to hold an aggressive lip and lose the adapter will I get back the handling a little bit. Do you think the adapter degrades the handling that much or the lower profile tire with 3 inches of added rubber. I remember wheel enhancements telling me something about ratios being changed by going to a larger or wider tire.
I can tell you one thing I miss the factory carrera s rims (I still have them) because there seems to be so much more tire in between the rim and road. I can't believe the difference a 30 series to 35 series makes in rubber.
I do like the look of the drop with the springs but there is nothing like stock, yet still I have the mod bug, why? Atleast I LOVE my B&M shortshift and Cayman Grills and think the GIAC is working well.
The rims look incredible. The forgelite 19x11 with a chrome lip and factory matched inner(stock fit for 997) I may get rid of the spacer and rebuild the 3piece wheels in the back with a shorter inner lip and 3.5 inch outer. Now that will be AWSOME. Reason I had to put an ADAPTER was because originally on the 997 Carrera S 19"s in Chrome sat too far inboard. I ended up using a 15mm spacer and I don't think that changed the handling. God I could push the car hard, and to the limit. The handlind was NEUTRAL, if it slid it was evenly, the car felt very stable at ANY speed.
What do you think, if I rebuild the rears to hold an aggressive lip and lose the adapter will I get back the handling a little bit. Do you think the adapter degrades the handling that much or the lower profile tire with 3 inches of added rubber. I remember wheel enhancements telling me something about ratios being changed by going to a larger or wider tire.
I can tell you one thing I miss the factory carrera s rims (I still have them) because there seems to be so much more tire in between the rim and road. I can't believe the difference a 30 series to 35 series makes in rubber.
05-24-2006, 06:10 PM
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Well, I'm not sure how to interpret your diminished handling, but changing track by 1" or by spacers will have only a tiny effect (imperceptible) to me. With very wide, low-profile tires, your alignment will, however, become more and more critical. I would recommend finding an alignment shop that does racing alignments and knows Porsche Boxsters and tell them what you're feeling. You definitely shouldn't be feeling mushy unless somehow the swaybars are softer than stock, or the installer left out some parts. Check your tire pressures, too. Boxsters are very sensitive to tire pressure and you are not running stock sizes, so you will most likely have to adjust (not like the factory tire pressures are a joke anyway).
05-24-2006, 10:04 PM
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Don't mean to sound critical here, but maybe you should research your planned mods a little more before leaping in?
The 987 is nicely balanced with stock wheels and tire sizes...what did you hope to achieve by going to 295s in the rear? Understeer? Softening the rear bars only adds to that ...
If it's looks your after, that's OK...but if your trying to improve on a well researched factory setup I would look for a matched/proven setup from a reputable tuner or aftermarket supplier.
The 987 is nicely balanced with stock wheels and tire sizes...what did you hope to achieve by going to 295s in the rear? Understeer? Softening the rear bars only adds to that ...
If it's looks your after, that's OK...but if your trying to improve on a well researched factory setup I would look for a matched/proven setup from a reputable tuner or aftermarket supplier.
Last edited by Chris C.; 05-25-2006 at 08:52 AM.
05-24-2006, 11:09 PM
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Originally Posted by jrok
996 hollow spokes with 14mm spacer in rear. Track only.
Looks like someone is having fun with their 987. From the rear picture, the 305/30s are noticeably smaller in diameter than the stock tires. Do you have PASM and/or any issues with the differences in diameter? If anything I would guess that you could slip the front a little more before nannies tried to kick in. Also, how much inboard clerance do you have left with that tire/wheel setup?
05-25-2006, 09:05 AM
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Let me explain more thoroughly. I installed H&R Springs on my car. Handling was..... Well atleast certain ride characteristics improved. But around hard corners stock was king. Once bumps are brought into play the car gets "a little" bit jittery around corners and certain rough surfaces or irregularities would bring out negative characteristics.
So at first I figured sway bars would cure this. The New rims I got were factory sized Carrera S Rims with factory sizes. Wheelenhancements is very very careful about staying with stock diameters and profile.
So naturally when I went with stiffer H&R swaybars I thought it would be a stiffer and racier application. I am not sure if I noticed the stiffer ride or even the reduction in body roll. I placed the bar on it's softest setting. (I guess I still have one more, tighter setting) I noticed a bit of loss in the control of the rear end. It definitely induced more oversteer. Although I didn't experience the actual act of oversteer. (I don't drive the car very hard as I have an exhaust issue and upon heavy acceleration I swear the loud scream from the exhaust is painful on my ears and embarrasing to say the least (I am sure you've read my other thread)
I bought a used set of Forgelite rims with lower profile tires and a much wider tire in the rear. I believe 3 inches wider in the rear, the same size in the front. I thought the wider tire would definitely cause much improved traction and would rectify the issue with oversteer.
I had the rims painted Basalt Black in the centre to match my vehicle and the first day I had them installed I discovered to my dismay that the tire wouldn't rotate as the inner rim rubbed the strut. So at this point my 15mm spacer I had used on the Carrera S rims and moved over to the Forgelite Rims became obsolete. Luckily Speed Gallery had a used 1" Adapter in stock. The tirer worked, cleared the strut and the fitment looked ABSOLUTELY AWSOME. Since the fitment was for a 997 the rims was on 2-2.5 Inches in the rear. Boxsters can accomodate a 3.5" lip in the rear so I had that thought in my head. (It's the one thing I love about 3piece wheels) So the adapters fit and the fit atleast looks PERFECT.
Driving experience. I was driving on Sunset BLVD and around a perfectly smooth corner the car stuck going 70+MPH. It did though feel very..... It's a hard feeling to explain. Bumps were transferred at a much greater rate in the rear only. It felt a tad unstable. I have heard stories of larger adapters causing handling issues seeing the rim is not quite as stable.
So the look is money and the fit is money but the handling is something to be desired. So now I figure my next step will be tighten the rear swaybars to see how that works. (I adjusted my tire pressure today. It seems as though my fronts were at 34lbs in the front, off by 2lbs (But only in the front right tire) and the rear was perfect pressure on the rear passenger tire and at 24lbs in the driver side, which I realize is horrible. (So I think I have a leak since the rims were painted and taken apart)
So now tire pressure is fixed and if the swaybar doesn't cure the problem them I may research Adapters of 1inch and plus sizes and see if the rebuild of the wheel would fix the problem. I could reduce the inner lip 1.75 inches, expand the outer lip to a 3.5inch size possible if possible. Thus alowing rim to fit without an adapter or spacer.
This is a last resort. This is a costly measure (500-750) and honestly I am saving and looking for a used factory exhaust and this is way back in the priority list. What are your thoughts.
I can imagine that expanding the rear track and widening the tire so much and keeping the front the same would really throw off handling. Hmmmm
So at first I figured sway bars would cure this. The New rims I got were factory sized Carrera S Rims with factory sizes. Wheelenhancements is very very careful about staying with stock diameters and profile.
So naturally when I went with stiffer H&R swaybars I thought it would be a stiffer and racier application. I am not sure if I noticed the stiffer ride or even the reduction in body roll. I placed the bar on it's softest setting. (I guess I still have one more, tighter setting) I noticed a bit of loss in the control of the rear end. It definitely induced more oversteer. Although I didn't experience the actual act of oversteer. (I don't drive the car very hard as I have an exhaust issue and upon heavy acceleration I swear the loud scream from the exhaust is painful on my ears and embarrasing to say the least (I am sure you've read my other thread)
I bought a used set of Forgelite rims with lower profile tires and a much wider tire in the rear. I believe 3 inches wider in the rear, the same size in the front. I thought the wider tire would definitely cause much improved traction and would rectify the issue with oversteer.
I had the rims painted Basalt Black in the centre to match my vehicle and the first day I had them installed I discovered to my dismay that the tire wouldn't rotate as the inner rim rubbed the strut. So at this point my 15mm spacer I had used on the Carrera S rims and moved over to the Forgelite Rims became obsolete. Luckily Speed Gallery had a used 1" Adapter in stock. The tirer worked, cleared the strut and the fitment looked ABSOLUTELY AWSOME. Since the fitment was for a 997 the rims was on 2-2.5 Inches in the rear. Boxsters can accomodate a 3.5" lip in the rear so I had that thought in my head. (It's the one thing I love about 3piece wheels) So the adapters fit and the fit atleast looks PERFECT.
Driving experience. I was driving on Sunset BLVD and around a perfectly smooth corner the car stuck going 70+MPH. It did though feel very..... It's a hard feeling to explain. Bumps were transferred at a much greater rate in the rear only. It felt a tad unstable. I have heard stories of larger adapters causing handling issues seeing the rim is not quite as stable.
So the look is money and the fit is money but the handling is something to be desired. So now I figure my next step will be tighten the rear swaybars to see how that works. (I adjusted my tire pressure today. It seems as though my fronts were at 34lbs in the front, off by 2lbs (But only in the front right tire) and the rear was perfect pressure on the rear passenger tire and at 24lbs in the driver side, which I realize is horrible. (So I think I have a leak since the rims were painted and taken apart)
So now tire pressure is fixed and if the swaybar doesn't cure the problem them I may research Adapters of 1inch and plus sizes and see if the rebuild of the wheel would fix the problem. I could reduce the inner lip 1.75 inches, expand the outer lip to a 3.5inch size possible if possible. Thus alowing rim to fit without an adapter or spacer.
This is a last resort. This is a costly measure (500-750) and honestly I am saving and looking for a used factory exhaust and this is way back in the priority list. What are your thoughts.
I can imagine that expanding the rear track and widening the tire so much and keeping the front the same would really throw off handling. Hmmmm
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05-26-2006, 08:23 PM
#8
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Well I am not sure I can help, but here are my views -
1. I have H&Rs on my non Pasm car and they are awesome. Less roll, firmer than stock with no ill ride effects. Yes, YOU might find your car was a bit more jittery -meaning rough - over bumps, but it should still have handled fine.
Perhaps you had something amiss with your car if you found stock was better?
2. New bars would do little for improving the handling feel in normal driving. I don't know the sizes of the H&Rs compared with stock, but I suspect the bars will make your car jittery and abrupt on bumps and introduce oversteer if they are significantly stiffer than stock. Anything that lessens traction on the rear end will induce oversteer.
Softening the bars would help reduce the oversteer from the new setup but again depends on their size, plus it sounds like you changed tire widths at the same time
3. It is unclear from your post, but you apparently went to OEM Boxster sized Carrera S wheels at the same time as the bars?? If they are 8/9.5s then they did not factor into the equation as they are the correct size. But you say you used a 15mm spacerso its unclear.
4. Adding more tire in the rear with wide rims may not be the right solution to reducing oversteer if it is caused by stiff or mismatched bars. Now you have a car that will likely understeer except on bad on bumps where it may snap oversteer. Furthermore, now you've changed the rear track...without changing the front track? More imbalance.
You carefully conside non-factory sized wheeks before adding them - using spacers is not ideal and should not be used to make wheels that fit badly work passably. Spacers themselves should NOT be a factor in the feel of a car in street driving if the wheels fit the car. I doubt you can feel them. The only concern point with spacers is potential axle/bearing wear in repeated high stress track use.
Obviously your tire pressures or rim leak are a major issue.
Your issue is likely with your bars and definitely at least partially with your change in tire size and track in the rear. In general, fix the problem in your setup, don't compound it by changing another variable.
With all of the work on your car, are you sure everything is tight? You haven't mentioned an alignment?
My advice is STOP!! Don't waste more money on wheels that don't fit or improve the handling of the car. Go back to your Carrera S wheels. Get an alignment. Try your bars on different settings to find a decent ride. CHANGE ONE THING AT A TIME.
If you cannot get back to a decent handling car, go back to stock bars. If you MUST have adjustable suspension components, START OVER - BUY a SET of matched shocks and springs and bars from Ruf or similar.
You took one of the worlds handling street cars (as reported by every magazine) and messed with it - sorry but I'm still not sure what you were trying to achieve!
Good luck.
1. I have H&Rs on my non Pasm car and they are awesome. Less roll, firmer than stock with no ill ride effects. Yes, YOU might find your car was a bit more jittery -meaning rough - over bumps, but it should still have handled fine.
Perhaps you had something amiss with your car if you found stock was better?
2. New bars would do little for improving the handling feel in normal driving. I don't know the sizes of the H&Rs compared with stock, but I suspect the bars will make your car jittery and abrupt on bumps and introduce oversteer if they are significantly stiffer than stock. Anything that lessens traction on the rear end will induce oversteer.
Softening the bars would help reduce the oversteer from the new setup but again depends on their size, plus it sounds like you changed tire widths at the same time
3. It is unclear from your post, but you apparently went to OEM Boxster sized Carrera S wheels at the same time as the bars?? If they are 8/9.5s then they did not factor into the equation as they are the correct size. But you say you used a 15mm spacerso its unclear.
4. Adding more tire in the rear with wide rims may not be the right solution to reducing oversteer if it is caused by stiff or mismatched bars. Now you have a car that will likely understeer except on bad on bumps where it may snap oversteer. Furthermore, now you've changed the rear track...without changing the front track? More imbalance.
You carefully conside non-factory sized wheeks before adding them - using spacers is not ideal and should not be used to make wheels that fit badly work passably. Spacers themselves should NOT be a factor in the feel of a car in street driving if the wheels fit the car. I doubt you can feel them. The only concern point with spacers is potential axle/bearing wear in repeated high stress track use.
Obviously your tire pressures or rim leak are a major issue.
Your issue is likely with your bars and definitely at least partially with your change in tire size and track in the rear. In general, fix the problem in your setup, don't compound it by changing another variable.
With all of the work on your car, are you sure everything is tight? You haven't mentioned an alignment?
My advice is STOP!! Don't waste more money on wheels that don't fit or improve the handling of the car. Go back to your Carrera S wheels. Get an alignment. Try your bars on different settings to find a decent ride. CHANGE ONE THING AT A TIME.
If you cannot get back to a decent handling car, go back to stock bars. If you MUST have adjustable suspension components, START OVER - BUY a SET of matched shocks and springs and bars from Ruf or similar.
You took one of the worlds handling street cars (as reported by every magazine) and messed with it - sorry but I'm still not sure what you were trying to achieve!
Good luck.
Last edited by Chris C.; 05-31-2006 at 11:35 AM.
