Bottom fwb angle
18 October 2004, 12:27 PM
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Bottom fwb angle
Hi,
Just bought myself a 4x4 1.6 preza hatch/estate to tow my race car round with. Nothing more than a hack I'm afraid, to use and abuse.
Anyway, after being thoroughly dissapointed with its handling its time I do something about it. A quick poke around the front subframe and its seems abundantly obvious to me that the rear bracket on the front lower wishbone wants to drop down, I'd say 6mm ish looking at the photos of the white line unit. Anyone have any preferences on how far to shim them?
What is the std employed method of lowering these beasts? And playing with the camber/castor on the front end? I was thinking of re-drilling the macstruts to hold the car lower, and with some camber on the front end. And from a wee squiz at the CD-manual thing I've got there is a chance of skimming a spacer I believe Subaru pack the front springs with? Also want to cut & shutting the front wb's to pull out some castor too, as well as increase front camber (WAY too much turn in oversteer as it is).
I'm about to fit rally spec tarmac stage springs on the rear with some KYB dampers to help towing and the throttle on understeer. But other than that, not really prepared to spend money on it, just my support vehicle (although the TLC I lavish on it might suprise a few people).
Any advise on the std employed techniques greatly received,
Thankyou,
Glen.
Just bought myself a 4x4 1.6 preza hatch/estate to tow my race car round with. Nothing more than a hack I'm afraid, to use and abuse.
Anyway, after being thoroughly dissapointed with its handling its time I do something about it. A quick poke around the front subframe and its seems abundantly obvious to me that the rear bracket on the front lower wishbone wants to drop down, I'd say 6mm ish looking at the photos of the white line unit. Anyone have any preferences on how far to shim them?
What is the std employed method of lowering these beasts? And playing with the camber/castor on the front end? I was thinking of re-drilling the macstruts to hold the car lower, and with some camber on the front end. And from a wee squiz at the CD-manual thing I've got there is a chance of skimming a spacer I believe Subaru pack the front springs with? Also want to cut & shutting the front wb's to pull out some castor too, as well as increase front camber (WAY too much turn in oversteer as it is).
I'm about to fit rally spec tarmac stage springs on the rear with some KYB dampers to help towing and the throttle on understeer. But other than that, not really prepared to spend money on it, just my support vehicle (although the TLC I lavish on it might suprise a few people).
Any advise on the std employed techniques greatly received,
Thankyou,
Glen.
18 October 2004, 12:56 PM
#2
Wow!
A real rally guy!!
ie DIY rather than a cheque book man!
I think you can do what you say very well:
The fromt lower w/bone rear mount needs to be about 6 mm lower away from the shell, BUT, if you rear mean to cut the STEEL front w/bones then you can gain all the caster you need then?
I cant see how you can find the room to drill the struts to take the upright 'up' to lower the car. A set of cheap springs will do the job fast and safely.
Not sure if all Impreza's have the large spacer on top of the struts, maybe just the UK to get the crash bumpers to the right height?
Camber bolts can be had off ebay for £10 or so, fit them front and back.
Good luck, nice to see hot Rodding still exists!
91
A real rally guy!!
ie DIY rather than a cheque book man!
I think you can do what you say very well:
The fromt lower w/bone rear mount needs to be about 6 mm lower away from the shell, BUT, if you rear mean to cut the STEEL front w/bones then you can gain all the caster you need then?
I cant see how you can find the room to drill the struts to take the upright 'up' to lower the car. A set of cheap springs will do the job fast and safely.
Not sure if all Impreza's have the large spacer on top of the struts, maybe just the UK to get the crash bumpers to the right height?
Camber bolts can be had off ebay for £10 or so, fit them front and back.
Good luck, nice to see hot Rodding still exists!
91
18 October 2004, 01:51 PM
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Hi,
The thought of paying money........ ? Jeepers, money? What was that again?
I was hoping to pull the lower mount down to get rid of the anti lift / anti dive that Subaru put on there. Unfortunately that in turn increases the castor, and for my driving style I want less - hence I have to cut & shut the wishbone.
But I will check out the camber bolts, thankyou, I'll scour ebay!
Toying with replacing the std front arb droplinks with some rosejoints/turnbuckles I have lying around. Maybe - if those rear spring prove too much of a handfull.
Also considering tightening the rear diff a little. Too much turn in AND throttle on understeer. Reckon it'll have a tighter diff. Any advise on that? Short of getting out my welder
Cheers,
Glen.
The thought of paying money........ ? Jeepers, money? What was that again?
I was hoping to pull the lower mount down to get rid of the anti lift / anti dive that Subaru put on there. Unfortunately that in turn increases the castor, and for my driving style I want less - hence I have to cut & shut the wishbone.
But I will check out the camber bolts, thankyou, I'll scour ebay!
Toying with replacing the std front arb droplinks with some rosejoints/turnbuckles I have lying around. Maybe - if those rear spring prove too much of a handfull.
Also considering tightening the rear diff a little. Too much turn in AND throttle on understeer. Reckon it'll have a tighter diff. Any advise on that? Short of getting out my welder
Cheers,
Glen.
18 October 2004, 05:48 PM
#4
Solid rear axle!
I hill climb my Sti v3, sort of a short tarmac stage (very short!)
Killed my understeer eventually by 8 Deg of caster, 2.5 deg neg camber all round, 22mm roll bars and fixed length solid links, wider rear track by 15 mm and real tyres, ie, ones that don't last (Kumho)
Left diffs alone as they cost too much.
I applaud your approach. Too simple to spend and spend.
911
I hill climb my Sti v3, sort of a short tarmac stage (very short!)
Killed my understeer eventually by 8 Deg of caster, 2.5 deg neg camber all round, 22mm roll bars and fixed length solid links, wider rear track by 15 mm and real tyres, ie, ones that don't last (Kumho)
Left diffs alone as they cost too much.
I applaud your approach. Too simple to spend and spend.
911
19 October 2004, 09:27 AM
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Thankyou 911. Dunno if I have courage to run a solid rear axle but it would be fun trying it! Oh I don't know, something just have to be done, for the shear bloody hell of it.
I'll try your settings out when I get the chance (life's too short, and only 24hrs in the day?), I have a tyre temp gun so I can quickly whip the thing into form.
I hillclimb my 7 (hence the need for a tow car/replacement 85hp hillclimb beast) in the ASWMC championships and they allow class 1B tyres in road legal. You recommend the Kuhmo's? I've very seriously considered switching over from my Colway fronts & Maxsport rears to Kuhmo all round. Yoko don't make cheap SS 15" tyres.
Just an aside, do the Subaru boys realise just how incredibly light the Subaru 15" alloys are? No kidding, it takes all my strength to lift the 15" Cosworth wheels I currently have on the 7. Had to get the stepladders out to pull my Subaru wheel down from the ceiling!!!!!!! My thinks I'm going to be re-drilling my hubs 5 stud.
Cheers,
Glen.
but it would be fun trying it! Oh I don't know, something just have to be done, for the shear bloody hell of it.I'll try your settings out when I get the chance (life's too short, and only 24hrs in the day?), I have a tyre temp gun so I can quickly whip the thing into form.
I hillclimb my 7 (hence the need for a tow car/replacement 85hp hillclimb beast) in the ASWMC championships and they allow class 1B tyres in road legal. You recommend the Kuhmo's? I've very seriously considered switching over from my Colway fronts & Maxsport rears to Kuhmo all round. Yoko don't make cheap SS 15" tyres.
Just an aside, do the Subaru boys realise just how incredibly light the Subaru 15" alloys are? No kidding, it takes all my strength to lift the 15" Cosworth wheels I currently have on the 7. Had to get the stepladders out to pull my Subaru wheel down from the ceiling!!!!!!! My thinks I'm going to be re-drilling my hubs 5 stud.
Cheers,
Glen.
19 October 2004, 10:06 AM
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Originally Posted by wurlyvalve
I was hoping to pull the lower mount down to get rid of the anti lift / anti dive that Subaru put on there. Unfortunately that in turn increases the castor, and for my driving style I want less - hence I have to cut & shut the wishbone.
But I will check out the camber bolts, thankyou, I'll scour ebay!
But I will check out the camber bolts, thankyou, I'll scour ebay!
Why do you want to reduce castor when you're complaining of turn-in understeer?
19 October 2004, 04:01 PM
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Yep, I realised that the wb horizontal angle (ad/pl) will not significantly adjust castor, however it is ignorant to assume it won't effect castor - I've spent too many hours playing corner weight games to know that it will effect castor! But if they pull the mount outboard to create the significant part of the 0.5castor I can live with the insignificant increase.
Sorry, must have made an error in my posts. My cars has loads of turn in OVERSTEER and throttle on understeer. Hence my desire for less castor.
In my previous post where I stated the car has too much turn in and throttle on understeer. I should have said it has too much turn in, and it also has throttle on understeer. My mistake.
Cheers,
Glen.
Sorry, must have made an error in my posts. My cars has loads of turn in OVERSTEER and throttle on understeer. Hence my desire for less castor.
In my previous post where I stated the car has too much turn in and throttle on understeer. I should have said it has too much turn in, and it also has throttle on understeer. My mistake.
Cheers,
Glen.
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19 October 2004, 06:30 PM
#8
The Midland Hill climb Championship allows any tyre whatsoever in my class. From 'O' rings to Avon slicks.
Changing wheels on a wet grassy paddock is no fun and dangerous so I run Kumho V70A soft on 16's for the race, and same tyre, medium compound on P1 17's for the road. Both are street legal, list 1B.
The 16's are so light compared to the P1's its untrue. My hill climb tweeked 911 has 15's and are featherweight!
I need 16's due to the brakes.
The Kumhos are faster on a climb than the Maxsport softest. Tried that, and went quicker on the same day with the 17's on instead. Not worth it at all.
The 205.45.16 in soft grain just like a slick after a 50 secong climb, are hot at the top of the hill too!
Really nice on the road also, cannot praise them enough. Even cheap (ish) at £100 a corner.
forget ALK's, just fit MRT race top mounts, tons of neg camber and tons of positive caster independantly.
911
Changing wheels on a wet grassy paddock is no fun and dangerous so I run Kumho V70A soft on 16's for the race, and same tyre, medium compound on P1 17's for the road. Both are street legal, list 1B.
The 16's are so light compared to the P1's its untrue. My hill climb tweeked 911 has 15's and are featherweight!
I need 16's due to the brakes.
The Kumhos are faster on a climb than the Maxsport softest. Tried that, and went quicker on the same day with the 17's on instead. Not worth it at all.
The 205.45.16 in soft grain just like a slick after a 50 secong climb, are hot at the top of the hill too!
Really nice on the road also, cannot praise them enough. Even cheap (ish) at £100 a corner.
forget ALK's, just fit MRT race top mounts, tons of neg camber and tons of positive caster independantly.
911
20 October 2004, 06:58 AM
#10
Yes, and that was right,and I did the same and they are still on! BUT, when you fit the MRT top mounts on they become superfluous as they provide the caster in skip loads in comparison.
I, like zillions others fitted the ALK/rollbars etc to my hill climber/road car, but under very hard driving on a (hill climb) track the power-on understeer was still a real problem. I would drive some bends on full lock!
Talking to Whiteline and MRT I discovered the MRT top mounts. Fitted these well after the ALK was on.
Following the Whiteline 'extreme' settings (on their web site) the car is a revelation now; you need the MRT tops to dial-in the extreme alignment settings.
This is why, if I were starting the Impeza game again I would simply go for the MRT tops and I think you can forget the ALK and maybe even the camber bolts in the front too. Big bonus also is the bottom wishbone bushes keep in line, there is no binding due to the bushes being mis-aligned in the way the ALK does. On my car this is very evident in the creeks and groans from the powerflex bushes when the car is moving slowly. They are in bind due to the ALK.
The ALK comes off this Xmas while I rebush and regrease the front end in preparation for the racing next year.
Phew! 911
I, like zillions others fitted the ALK/rollbars etc to my hill climber/road car, but under very hard driving on a (hill climb) track the power-on understeer was still a real problem. I would drive some bends on full lock!
Talking to Whiteline and MRT I discovered the MRT top mounts. Fitted these well after the ALK was on.
Following the Whiteline 'extreme' settings (on their web site) the car is a revelation now; you need the MRT tops to dial-in the extreme alignment settings.
This is why, if I were starting the Impeza game again I would simply go for the MRT tops and I think you can forget the ALK and maybe even the camber bolts in the front too. Big bonus also is the bottom wishbone bushes keep in line, there is no binding due to the bushes being mis-aligned in the way the ALK does. On my car this is very evident in the creeks and groans from the powerflex bushes when the car is moving slowly. They are in bind due to the ALK.
The ALK comes off this Xmas while I rebush and regrease the front end in preparation for the racing next year.
Phew! 911
20 October 2004, 09:50 AM
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You're a star 911. Will look into the top mounts, for sure.
Yep, running hard compound (disc now) Maxsports. I'm beginning to catch up the competition but couldn't help but feel I was at a disadvantage to the Yoko's. Went to the NEC autosport show and 'squidged' the Yokos, then 'squidged' the V70's, WOW! And nearly half the price too. I think I'll switch in very short order.
In the wet mind I am faster than the yoko boys. I've just switched to motorbike calipers - hence I need 15's as the banjo and nipple are in just about the perfectly wrong place! And I'm about to wrap a steel cradle around them as they do flex some! but hey - cheap - and who needs brakes?
Cheers,
Glen.
Yep, running hard compound (disc now) Maxsports. I'm beginning to catch up the competition but couldn't help but feel I was at a disadvantage to the Yoko's. Went to the NEC autosport show and 'squidged' the Yokos, then 'squidged' the V70's, WOW! And nearly half the price too. I think I'll switch in very short order.
In the wet mind I am faster than the yoko boys. I've just switched to motorbike calipers - hence I need 15's as the banjo and nipple are in just about the perfectly wrong place! And I'm about to wrap a steel cradle around them as they do flex some! but hey - cheap - and who needs brakes?
Cheers,
Glen.
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