Live Axle..vs..irs

[gary6303]

would like advice on rear axle set up, ha4 axle or custom irs, so many subframed irs i could use, alot of cutting the rear floor, boot area i know but would it rearly be worth the hassel. ha 4 axle is very strong but can be twitchy on our shit roads, irs can have toe,camber set up and can be better on our crap highways, has anyone fitted irs to a manta coupe or is it just not worth it.

[mantaray]

Give Simon p at suffolkcountymantas a ring, I know he fitted IRS to his A.

[lamchop77]

would like advice on rear axle set up, ha4 axle or custom irs, so many subframed irs i could use, alot of cutting the rear floor, boot area i know but would it rearly be worth the hassel. ha 4 axle is very strong but can be twitchy on our shit roads, irs can have toe,camber set up and can be better on our crap highways, has anyone fitted irs to a manta coupe or is it just not worth it.

I fitted a sierra IRS rear to the Kadett grassert that i have. Reason i did it was to improve traction on the dirt which it has done quite well. The original set up was pretty crap on starts although handled pretty well. Good thing was that the spring mounts lined up almost perfectly. I managed to fit it all in over a long weekend, started friday and drove it sunday late afternoon. Needed to cut the floor and sills for clearance but the mounting could have been modded to fit without this i'm sure. I only did it so that i could use any std subframe in the event of damage occuring. I would say its worth doing as a cossy/xr4i rear with discs could be fitted which already has an lsd fitted. Lsd's are available for the std units and are way cheaper than the manta ones. The sierra std rears are really strong, seen 365bhp being run through a 1.6 diff over a period of about 5 years with no problems.

You could fab up a custom rear using upper and lower wishbones using the sierra bits, that would give you a fully adjustable rear end if you used spherical bearings. It also has the benefit of reducing the unsprung weight and lowers the rear roll centre. BMW rears couuld also be used but i have never looked at them up close but they are very similar in the layout.

HTH

Chris

[gary6303]

I fitted a sierra IRS rear to the Kadett grassert that i have. Reason i did it was to improve traction on the dirt which it has done quite well. The original set up was pretty crap on starts although handled pretty well. Good thing was that the spring mounts lined up almost perfectly. I managed to fit it all in over a long weekend, started friday and drove it sunday late afternoon. Needed to cut the floor and sills for clearance but the mounting could have been modded to fit without this i'm sure. I only did it so that i could use any std subframe in the event of damage occuring. I would say its worth doing as a cossy/xr4i rear with discs could be fitted which already has an lsd fitted. Lsd's are available for the std units and are way cheaper than the manta ones. The sierra std rears are really strong, seen 365bhp being run through a 1.6 diff over a period of about 5 years with no problems.

You could fab up a custom rear using upper and lower wishbones using the sierra bits, that would give you a fully adjustable rear end if you used spherical bearings. It also has the benefit of reducing the unsprung weight and lowers the rear roll centre. BMW rears couuld also be used but i have never looked at them up close but they are very similar in the layout.

HTH

Chris

Thanks criss very helpfull any picks of convertion.

[lamchop77]

Thanks criss very helpfull any picks of convertion.

No i haven't unfortunately. Got some of the measurements knocking around somewhere. Might be able to get some sorted but not for a while.

Chris

[gary6303]

ok mate many thanks.

[MANTAMAN]

Worms, can of, OPEN!!!

fitting a different suspension system on a car needs a huge amount of calculation, radius of suspension arm travel, roll centers, etc etc, get them wrong and you have foul handling car.

[madmantamik]

i pondered for a while about a rear setup on mine wether to go for an lsd in the standard axle or fit another type of rear beam . the problems to bear in mind are the pcd of the wheels and the overall width to the outer faces of the hubs . the standard sierra beam is far too wide for the standard manta without making a custom subframe, this will also mean getting custom driveshafts made .i finally decided on using a subaru impreza turbo rear beam which would give a very strong rear lsd, irs with adjustable castor and a disc conversion in one go. the conversion is nearly 50% complete now und has not been as easy as i had hoped but hopefully will be worth it , i should also add that i have a 400r not a standard shell that will be sitting on 12" wide rear and 10" wide front porsche boxster 18" rims .

[gary6303]

The only thing that puts me off having irs is maybe if i took car for mot and the guy goes have'nt seen one of those for a long time, i see you've put an irs on it, have you had a sva test done as its now law, so what do i say then, can be a lot of hassel, if i go for a very strong 4ha axle i can link it all up and keep character of the car and may be get away with it, these bloody new laws that keep popping up out of knowere can realy pxss us off. I work on a lot of cars every day and see so much potential for the manta ie bmw 1 series,mazda rx7,nissan 200sx,honda s200,mercedes type210 all have subframed rear ends so can be removed as a complete unit with its floor and fitted to the manta as such, but i do love the way the manta handles so will proberly go with the 4ha axle because it will look like its original and a lot less work to.

[madmantamik]

as i understand the fundamentals of the sva test it requires that the three main components of a vehicle which are the rear suspension the gearbox and the engine remain as from factory to comply with the certificate of confirmity. if two of these are not as supplied by factory then an sva is required.so to the letter of the sva, changing only the rear suspension should not require a sva .but it also helps if your friend is an mot tester.

[gary6303]

mmmm might have a little trouble then with my manta and my bmw, fitted a c20let into my e30, had to cut out the baulkhead, trans tunnel on both cars made a new baulkhead, trans tunnel, pedal boxed the e30 for the brakes.the manta has a large non standard engine,box so both may need a sva test. this test, is it just to show that the mods you've done are safe.

[mantaray]

this test, is it just to show that the mods you've done are safe.

NO. Single Vehicle Approval (SVA) scheme is a pre-registration inspection for vehicles that haven't been type approved to British or European standards. The purpose of the scheme is to ensure that these vehicles are designed and constructed to suitable safety standards before they are used on public roads. Ie 2010 safety standards.

See here, http://www.direct.gov.uk/en/Motoring/BuyingAndSellingAVehicle/ImportingAndExportingAVehicle/DG_4022105

Now you will say that your Manta is type approved to British or European standards, BUT if you have modified the chassis (monocoque),which you have, then your car is no longer a Manta and needs a new identity. As it is classed as a new car it will need a SVA and need to meet the current safty rules, eg Air bags, crusable inpact areas ect.

See here http://www.direct.gov.uk/en/Motoring/BuyingAndSellingAVehicle/RegisteringAVehicle/DG_10014199

Another good site to visit is, http://www.the-ace.org.uk/ They will be able to help you through the mine field and give you advice.

Now I know some peaple beleave that the rules will never be inforced and are unworkable, BUT the rules are the law and as the EU wish to remove all old cars off our roads and this country is run from the EU, egnor them at your own risk.

[gary6303]

have to agree with you mantaray, if modding a vehicle of any age it must be safe and approved, so im gonna stick with my original plan and fit a 4ha scimitar rear axle as it looks original plus i dont lose the character of my manta, gotta stick to the rules or it will come back and bite you later on. .

[simon p]

have to agree with you mantaray, if modding a vehicle of any age it must be safe and approved, so im gonna stick with my original plan and fit a 4ha scimitar rear axle as it looks original plus i dont lose the character of my manta, gotta stick to the rules or it will come back and bite you later on. .

I agree with Mantaray too. You can change the rear axle but make sure you fit it using the stock body mounts, if you modify the shell (i.e four link it) to locate the new axle, it will need an IVA. Some people think it's ok but it's not.

Last thing, if you do gone down this route, don't post pic's as i know the kill joys frequent forums like ours to see what's been being built, it helps make their jobs alot easier. I've stopped posting pics for a while now, just for this very reason.

[Retro Power]

Agreed to some extent, though really, if you want to sort the job properly, then just SVA it. Yep it will cost a chunk, but the relevance of that depends on the budget the car is built to.

Worrying about the test on a 2k car is very relevant, on a 20k car its not.

NO. Single Vehicle Approval (SVA) scheme is a pre-registration inspection for vehicles that haven't been type approved to British or European standards. The purpose of the scheme is to ensure that these vehicles are designed and constructed to suitable safety standards before they are used on public roads. Ie 2010 safety standards.

See here, http://www.direct.go...icle/DG_4022105

Now you will say that your Manta is type approved to British or European standards, BUT if you have modified the chassis (monocoque),which you have, then your car is no longer a Manta and needs a new identity. As it is classed as a new car it will need a SVA and need to meet the current safty rules, eg Air bags, crusable inpact areas ect.

See here http://www.direct.go...cle/DG_10014199

Another good site to visit is, http://www.the-ace.org.uk/ They will be able to help you through the mine field and give you advice.

Now I know some peaple beleave that the rules will never be inforced and are unworkable, BUT the rules are the law and as the EU wish to remove all old cars off our roads and this country is run from the EU, egnor them at your own risk.

Just a footnote, SVA is now IVA, and NO, you DON'T need airbags, crushable structure etc, the rules are written to allow kit car registration to be carried out sensibly. The top link in the post above is NOT relevant to our vehicles (unless you are planning to use your manta as a bus or armoured car! )

The IVA rules are the relevant ones, and are different

Have a look on www.locostbuilders.co.uk at the IVA/LEGAL section.

Having been through the SVA/IVA process, though it is time/money consuming and a little frustrating, it's not the very end of the serious car modifying world!

I hate the rules, but if we have to abide by them then so be it.

Edited January 16, 2011 by Retro Power

[lamchop77]

Agreed to some extent, though really, if you want to sort the job properly, then just SVA it. Yep it will cost a chunk, but the relevance of that depends on the budget the car is built to.

Worrying about the test on a 2k car is very relevant, on a 20k car its not.

Just a footnote, SVA is now IVA, and NO, you DON'T need airbags, crushable structure etc, the rules are written to allow kit car registration to be carried out sensibly. The top link in the post above is NOT relevant to our vehicles (unless you are planning to use your manta as a bus or armoured car! )

The IVA rules are the relevant ones, and are different

Have a look on www.locostbuilders.co.uk at the IVA/LEGAL section.

Having been through the SVA/IVA process, though it is time/money consuming and a little frustrating, it's not the very end of the serious car modifying world!

I hate the rules, but if we have to abide by them then so be it.

Just printed off the IVA document to have a read. Reading through it in paragragh 1.9 When does IVA not apply? it quotes

"Old vehicles (i.e.passenger cars and light goods vehicles over 10 years old and large goods vehicles over 25 years old)"

Reading further on it also states

"In all cases, IVA (whether basic or normal) is only required for passenger cars and light goods vehicles LESS THAN 10 YEARS OLD, which require first licensing and registration in the UK.

As far as i can tell quickly reading through the document all cars over 10 years old don't need this and as this replaces the SVA then we can't submit cars over 10 years old as they won't be accepted.

Can anyone tell me exactly where it says modded cars need this as the document seems to disagree.

Cheers

Chris

[simon p]

Just printed off the IVA document to have a read. Reading through it in paragragh 1.9 When does IVA not apply? it quotes

"Old vehicles (i.e.passenger cars and light goods vehicles over 10 years old and large goods vehicles over 25 years old)"

Reading further on it also states

"In all cases, IVA (whether basic or normal) is only required for passenger cars and light goods vehicles LESS THAN 10 YEARS OLD, which require first licensing and registration in the UK.

As far as i can tell quickly reading through the document all cars over 10 years old don't need this and as this replaces the SVA then we can't submit cars over 10 years old as they won't be accepted.

Can anyone tell me exactly where it says modded cars need this as the document seems to disagree.

Cheers

Chris

Its all about identity. If you modify the body of a car of any age, it losses it identity, to put it back on the road it will then be treated as a new car (less than 10 years old), hence an IVA is required. You then have to re-build the whole car to meet the IVA requirements, from the leading edge of the front bumper to the rear fog light placement. If it passes, it will be given a Q reg too. It sucks but thems the rules. Best to work within rules, if you don't modify the body, your 5 points arn't lost, therefore making it a lot easier to retain the original identity.

Edited January 19, 2011 by simon p

[lamchop77]

Its all about identity. If you modify the body of a car of any age, it losses it identity, to put it back on the road it will then be treated as a new car (less than 10 years old), hence an IVA is required. You then have to re-build the whole car to meet the IVA requirements, from the leading edge of the front bumper to the rear fog light placement. If it passes, it will be given a Q reg too. It sucks but thems the rules. Best to work within rules, if you don't modify the body, your 5 points arn't lost, therefore making it a lot easier to retain the original identity.

Right

So if i wanted to 5 link any car and fit a different axle, coil overs etc i need an IVA. What is going to be inspected on the vehicle? The actual mods or the whole thing? I mess around with older cars so 60/70and 80's so i'm concerned about the anti theft, airbags etc bits of the IVA. Can someone please clarify on these points?

Thanks

Chris

[Leon]

The whole car is inspected but airbags and all that jazz are not relevant.

Read this:

http://www.the-ace.org.uk/Chassis-and-Monocoque-Modification.html

http://www.transportoffice.gov.uk/crt/repository/IVA-Inspection-Manual-for-M1-Passenger-Cars.pdf

[opel2000]

Hmm.......

I try not to get drawn into these type of topics, (due to knowing Jack Shit on SVA, IVA) but this one has drawn my attention.

Firstly just how the hell is any tester going to be able to test "Crushable" area's without actually crashing the car?

In the same way "Airbags" how are they going to test them without crashing the car, I was in the posession of a Cally Turbo steering column, complete with air bag steering wheel, I could have fitted it to the Manta and it would need some sort of tell tale light that would say "Air Bag" that would disappear when ign is turned on hmmmmmm pretty much just like the oil warning light if you get my drift.

Personally if a car I was modding required to pass some sort of vehicle approval to say "Yes that's ok mate" it personally wouldn't bother me one bit as I would know the work I would have done on say......... mounting an IRS would be more than adequate to say the least.

Going back 10 years when I fitted a Meagre 8 valve SEH to my old red B I had to get a garage report to satisfy the insurance, many garages would not touch me with a barge pole, the RAC said they would give an overall vehicle assesment to the insurers for close to £200 sovs, got it sorted in the end and more than prepared to go through any rigmorole required to drive a car that I see fit, built to how I want it.

Nice thing though is.......... I always had that report to pass on to any other prospective insurer to cover my ass.

I think at the end of the day it is only the assholes that haven't got a fffing clue what they are doing when cutting and welding that really have any need to fear as I suspect it is these muppets that any legislation is aimed at.

Would be very surprised that if I fitted an IRS to a Manta (looked into fitting one off of the Carlton many years back) and come MOT time the tester would look at all the really quite most jolly splendid fabrication and strong structural steelwork with sooper clean weld runs, to turn round and say "F**K off C**T we aint testing that, I would actually expect a pass.

Edit:-

Did type something else but certain people would have got the arse so I backspaced it

Edited January 20, 2011 by opel2000

[gary6303]

...i love the way you put things opel 2000.. .

[mantaray]

Ok, let me try and explane why fitting an IRS would meen that your car needs an IVA/SVA.

As taken from the goverment web site:

Allocating a vehicle registration mark

The vehicle must score eight or more points to retain the original registration mark. If less than eight points are scored or a second-hand or modified chassis or altered monocoque bodyshell is used an Individual Vehicle Approval (IVA), enhanced single vehicle approval (ESVA), single vehicle approval (SVA) or motorcycle single vehicle approval (MSVA) certificate will be required to register the vehicle. A 'Q' prefix registration number will be allocated.

Scoring components

The following values will be allocated to the major components used:

* chassis or body shell (body and chassis as one unit - monocoque ie direct replacement from the manufacturer) (original or new) = 5 points

* suspension = 2 points

* axles = 2 points

* transmission = 2 points

* steering assembly = 2 points

* engine = 1 point

So by fitting an IRS, the chances are you will be modified the monocoque.....fail you now need it tested.

If by some chance you can fit the IRS without modified the monocoque, ( you can add brackets to original monocoque, but must not cut anything away.)then you would loss 4 points( suspension+axles)that would leave you with:

monocoque = 5 points

transmission = 2 points

engine = 1 point

steering assembly = 2 points

A total of 10 points, so no problem.

It's the "If a altered monocoque bodyshell is used an Individual Vehicle Approval (IVA)...will be required to register the vehicle" cloase that causes all the problems.

As soon as you altered monocoque by enlarging the tunnel, cutting the bulk head ect. you fall into the relms of the IVA.

Now what the IVA rules are, seems to be a bit of a confustion. as I understand them, by altered monocoque you have changed the identity of you car, Ie it is no longer a Manta, and so needs an IVA to give it a new identity. because it has no identity it is classed as a new car and so must meet the current 2011 safty rules.

From what Retro Power seems to be saying, it would seem that my understanding is wrong, so I'll leave that part open to discustion. But regardless of how hard or easy the IVA is to pass, if you alter the monocoque of your car, you will need an IVA.

[lamchop77]

Ok, let me try and explane why fitting an IRS would meen that your car needs an IVA/SVA.

As taken from the goverment web site:

Allocating a vehicle registration mark

The vehicle must score eight or more points to retain the original registration mark. If less than eight points are scored or a second-hand or modified chassis or altered monocoque bodyshell is used an Individual Vehicle Approval (IVA), enhanced single vehicle approval (ESVA), single vehicle approval (SVA) or motorcycle single vehicle approval (MSVA) certificate will be required to register the vehicle. A 'Q' prefix registration number will be allocated.

Scoring components

The following values will be allocated to the major components used:

* chassis or body shell (body and chassis as one unit - monocoque ie direct replacement from the manufacturer) (original or new) = 5 points

* suspension = 2 points

* axles = 2 points

* transmission = 2 points

* steering assembly = 2 points

* engine = 1 point

So by fitting an IRS, the chances are you will be modified the monocoque.....fail you now need it tested.

If by some chance you can fit the IRS without modified the monocoque, ( you can add brackets to original monocoque, but must not cut anything away.)then you would loss 4 points( suspension+axles)that would leave you with:

monocoque = 5 points

transmission = 2 points

engine = 1 point

steering assembly = 2 points

A total of 10 points, so no problem.

It's the "If a altered monocoque bodyshell is used an Individual Vehicle Approval (IVA)...will be required to register the vehicle" cloase that causes all the problems.

As soon as you altered monocoque by enlarging the tunnel, cutting the bulk head ect. you fall into the relms of the IVA.

Now what the IVA rules are, seems to be a bit of a confustion. as I understand them, by altered monocoque you have changed the identity of you car, Ie it is no longer a Manta, and so needs an IVA to give it a new identity. because it has no identity it is classed as a new car and so must meet the current 2011 safty rules.

From what Retro Power seems to be saying, it would seem that my understanding is wrong, so I'll leave that part open to discustion. But regardless of how hard or easy the IVA is to pass, if you alter the monocoque of your car, you will need an IVA.

Yeah as i thought. I know about the point system but the monocoque bit is new to me.

How are all the historic rally cars going to cope then? Grp 4 escorts and the like are going to have to be IVA'd and given Q plates if thats the case.

Cheers for the info anyway

Chris

[Retro Power]

Its all about identity. If you modify the body of a car of any age, it losses it identity, to put it back on the road it will then be treated as a new car (less than 10 years old), hence an IVA is required. You then have to re-build the whole car to meet the IVA requirements, from the leading edge of the front bumper to the rear fog light placement. If it passes, it will be given a Q reg too. It sucks but thems the rules. Best to work within rules, if you don't modify the body, your 5 points arn't lost, therefore making it a lot easier to retain the original identity.

As Simon says above, if a modified vehicle requires an IVA, then from that point on its treated as a new vehicle.

At least the one (admittedly slight! ) benefit is there is no MOT for 3 years.

My own "lotus 7 clone" with XE power has just had its very first MOT, despite being built 4 years ago from second hand parts.

Ok, let me try and explane why fitting an IRS would meen that your car needs an IVA/SVA.

As taken from the goverment web site:

Allocating a vehicle registration mark

The vehicle must score eight or more points to retain the original registration mark. If less than eight points are scored or a second-hand or modified chassis or altered monocoque bodyshell is used an Individual Vehicle Approval (IVA), enhanced single vehicle approval (ESVA), single vehicle approval (SVA) or motorcycle single vehicle approval (MSVA) certificate will be required to register the vehicle. A 'Q' prefix registration number will be allocated.

Scoring components

The following values will be allocated to the major components used:

* chassis or body shell (body and chassis as one unit - monocoque ie direct replacement from the manufacturer) (original or new) = 5 points

* suspension = 2 points

* axles = 2 points

* transmission = 2 points

* steering assembly = 2 points

* engine = 1 point

So by fitting an IRS, the chances are you will be modified the monocoque.....fail you now need it tested.

If by some chance you can fit the IRS without modified the monocoque, ( you can add brackets to original monocoque, but must not cut anything away.)then you would loss 4 points( suspension+axles)that would leave you with:

monocoque = 5 points

transmission = 2 points

engine = 1 point

steering assembly = 2 points

A total of 10 points, so no problem.

It's the "If a altered monocoque bodyshell is used an Individual Vehicle Approval (IVA)...will be required to register the vehicle" cloase that causes all the problems.

As soon as you altered monocoque by enlarging the tunnel, cutting the bulk head ect. you fall into the relms of the IVA.

Now what the IVA rules are, seems to be a bit of a confustion. as I understand them, by altered monocoque you have changed the identity of you car, Ie it is no longer a Manta, and so needs an IVA to give it a new identity. because it has no identity it is classed as a new car and so must meet the current 2011 safty rules.

From what Retro Power seems to be saying, it would seem that my understanding is wrong, so I'll leave that part open to discustion. But regardless of how hard or easy the IVA is to pass, if you alter the monocoque of your car, you will need an IVA.

Yea its tricky to understand I admit!

Although your car will "become" a NEW car, it doesn't have to comply with current TYPE APPROVAL safety regulations. The IVA requirements are for LOW VOLUME ONLY. That;'s the get-out that we have to be thankful for. For an IVA vehicle we have no crash testing, pedestrian impact, airbag requirements etc etc. If you get a copy of the IVA manual you'll see.

The worst bits from our points of view are:

1) Radii, every "contactable" surface on the vehicle has to comply with various minimum radius requirements, which are very awkward to acheive (the philips heads on various light screws will fail, as will opel manta badges among other things)

2) Engine emmissions: unless you can PROVE engine age with a letter from the manufacturer or a V5 from the engine donor car, then any car must pass latest emissions regs......If you CAN prove engine age is of some previous emmissions standard then it must pass that appropriate test. A lot of manufacturers simply don't supply engine ago proof though!!

[opel2000]

Engine emmissions: unless you can PROVE engine age with a letter from the manufacturer or a V5 from the engine donor car, then any car must pass latest emissions regs......If you CAN prove engine age is of some previous emmissions standard then it must pass that appropriate test. A lot of manufacturers simply don't supply engine ago proof though!!

Aha!! so that is why you wanted the V5 from my old Cally that your engine came out of....... Like I said I "Don't really know too much about this IVA SVA business"

What canI say? But it is an education on here, good post and quite a good topic methinks....