Omega Owners Forum

Chat Area => General Car Chat => Topic started by: Webby the Bear on 11 December 2013, 21:41:53

Title: Why do we have a subframe...
Post by: Webby the Bear on 11 December 2013, 21:41:53
...as oppose to bolting suspension and steering parts straight to the chassis?

Sorry, thought I'd keep this topic separate from my wheel alignment one for ease of reference :)
Title: Re: Why do we have a subframe...
Post by: 05omegav6 on 11 December 2013, 21:43:27
Subframe is an efficient way of adding strength where it's needed :y also makes it a damn sight easier to build...
Title: Re: Why do we have a subframe...
Post by: Andy B on 11 December 2013, 21:57:31
...as oppose to bolting suspension and steering parts straight to the chassis?

 .......

because cars now are a monocoque construction & don't have a chassis  ;)
Title: Re: Why do we have a subframe...
Post by: 05omegav6 on 11 December 2013, 22:01:46
...as oppose to bolting suspension and steering parts straight to the chassis?

 .......

because cars now are a monocoque construction & don't have a chassis  ;)
Landrover never got that memo ;D
Title: Re: Why do we have a subframe...
Post by: Webby the Bear on 11 December 2013, 22:02:58
...as oppose to bolting suspension and steering parts straight to the chassis?

 .......

because cars now are a monocoque construction & don't have a chassis  ;)

whats the difference andy? :)
Title: Re: Why do we have a subframe...
Post by: Webby the Bear on 11 December 2013, 22:06:14
Subframe is an efficient way of adding strength where it's needed :y also makes it a damn sight easier to build...

thanks al  :y
Title: Re: Why do we have a subframe...
Post by: 05omegav6 on 11 December 2013, 22:15:29
Monocoque is a car without a chassis, ie all one piece.
Chassis is just that... a frame on which everything else is mounted.

Watch a series or two of American Hot Rod, and all will be clearer...

Examples...
Omega is a monocoque design.
Rover P4 has a separate chassis.
F body Camaro/Firebird/Trans Am has a monocoque shell which ends at the firewall. Everything infront of the doors is on a chassis bolted to the firewall.

Some cars, like the Disco3 have a full chassis, with a monocoque shell on top, which is why they're so bloody heavy ::)
Title: Re: Why do we have a subframe...
Post by: Andy B on 11 December 2013, 22:17:55
...as oppose to bolting suspension and steering parts straight to the chassis?

 .......

because cars now are a monocoque construction & don't have a chassis  ;)

whats the difference andy? :)

This is a chassis ....... there are other variations

(http://image.popularhotrodding.com/f/tech/1208phr_64_81_muscle_car_chassis_guide/42121272/1208phr-02-z%2B64-81-muscle-car-chassis-guide%2B.jpg)

a modern car has the rigidity built into the various box sections & pressings including the way the windscreen is glued in ie monocoque

(http://media.caranddriver.com/images/12q3/472796/2015-volkswagen-golf-safety-chassis-diagram-photo-481021-s-1280x782.jpg)
Title: Re: Why do we have a subframe...
Post by: Andy B on 11 December 2013, 22:18:39
Ooops! a bit big!  :o :o
Title: Re: Why do we have a subframe...
Post by: Webby the Bear on 11 December 2013, 22:18:47
Monocoque is a car without a chassis, ie all one piece.
Chassis is just that... a frame on which everything else is mounted.

Watch a series or two of American Hot Rod, and all will be clearer...

Examples...
Omega is a monocoque design.
Rover P4 has a separate chassis.
F body Camaro/Firebird/Trans Am has a monocoque shell which ends at the firewall. Everything infront of the doors is on a chassis bolted to the firewall.

Some cars, like the Disco3 have a full chassis, with a monocoque shell on top, which is why they're so bloody heavy ::)

Thanks Al. im still to check those out :(.....

but for the purpose of the subframe question its either the chassis or monocoque that the subframe bolts to? :)
Title: Re: Why do we have a subframe...
Post by: Sir Tigger KC on 11 December 2013, 22:19:06
Subframe is an efficient way of adding strength where it's needed :y also makes it a damn sight easier cheaper to build...

Alternatively  ;)
Title: Re: Why do we have a subframe...
Post by: Andy B on 11 December 2013, 22:19:44
.....
Some cars, like the Disco3 have a full chassis, with a monocoque shell on top, which is why they're so bloody heavy ::)

And the Triumph Herald!  ;D ;D ;D ;D
Title: Re: Why do we have a subframe...
Post by: Andy B on 11 December 2013, 22:21:19
....
but for the purpose of the subframe question its either the chassis or monocoque that the subframe bolts to? :)

it bolts to the monocoque on a bit we call the chassis legs ...... but it's not really a chassis, just a term that's still used  ;)
Title: Re: Why do we have a subframe...
Post by: Webby the Bear on 11 December 2013, 22:23:39
Thanks Andy.

so in very simple form (for me lol) the chassis is a frame in which the car is built on i.e. body attached, suspension attached etc etc and the monocoque is an entire ''body'' that is strong when bolted together thus not needing the ''frame''?

Title: Re: Why do we have a subframe...
Post by: Webby the Bear on 11 December 2013, 22:24:39
....
but for the purpose of the subframe question its either the chassis or monocoque that the subframe bolts to? :)

it bolts to the monocoque on a bit we call the chassis legs ...... but it's not really a chassis, just a term that's still used  ;)

got ya mate thanks for that....which is the chassis leg on your golf pic?
Title: Re: Why do we have a subframe...
Post by: 05omegav6 on 11 December 2013, 22:25:24
Thanks Andy.

so in very simple form (for me lol) the chassis is a frame in which the car is built on i.e. body attached, suspension attached etc etc and the monocoque is an entire ''body'' that is strong when bolted together thus not needing the ''frame''?


Repeated for clarity...

Quote
Chassis is just that... a frame on which everything else is mounted.
Title: Re: Why do we have a subframe...
Post by: 05omegav6 on 11 December 2013, 22:26:07
The red sticky out bits at the front ::)
Title: Re: Why do we have a subframe...
Post by: Andy B on 11 December 2013, 22:26:17
....
but for the purpose of the subframe question its either the chassis or monocoque that the subframe bolts to? :)

it bolts to the monocoque on a bit we call the chassis legs ...... but it's not really a chassis, just a term that's still used  ;)

got ya mate thanks for that....which is the chassis leg on your golf pic?

The peachy coloured parts that run fore & aft just inboard of the front wheels  :)
Title: Re: Why do we have a subframe...
Post by: Webby the Bear on 11 December 2013, 22:26:48
Thanks Andy.

so in very simple form (for me lol) the chassis is a frame in which the car is built on i.e. body attached, suspension attached etc etc and the monocoque is an entire ''body'' that is strong when bolted together thus not needing the ''frame''?


Repeated for clarity...

Quote
Chassis is just that... a frame on which everything else is mounted.

sorry mate.... I get confused sometimes  :-[ :-[ :-[ ::)
Title: Re: Why do we have a subframe...
Post by: Webby the Bear on 11 December 2013, 22:31:06
Thanks girls..... is that golf pretty much what the omega would look like in the same ''coloured-panel'' photo?
Title: Re: Why do we have a subframe...
Post by: 05omegav6 on 11 December 2013, 22:37:15
Alot more metal on the Omega... remind me not to sit next to a rear door in that Golf, sfa crash protection :o

But basically yup...

Get yourself one of theses...

 http://www.ebay.co.uk/itm/350889424723?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649  (http://www.ebay.co.uk/itm/350889424723?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649)

Will give you a much better idea of what's what :y
Title: Re: Why do we have a subframe...
Post by: Webby the Bear on 11 December 2013, 22:38:44
Alot more metal on the Omega... remind me not to sit next to a rear door in that Golf, sfa crash protection :o

But basically yup...

Get yourself one of theses...

 http://www.ebay.co.uk/itm/350889424723?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649  (http://www.ebay.co.uk/itm/350889424723?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649)

Will give you a much better idea of what's what :y

A lot more.... as in thicker panels?

That looks really good, thanks al  :y :y :y
Title: Re: Why do we have a subframe...
Post by: 05omegav6 on 11 December 2013, 22:39:46
Thicker panels, and more of them :y
Title: Re: Why do we have a subframe...
Post by: Webby the Bear on 11 December 2013, 22:43:45
Thicker panels, and more of them :y

Cheers mate  :y :y :y :y :y
Title: Re: Why do we have a subframe...
Post by: 2woody on 15 December 2013, 11:57:21
Omega has a front subframeto make it easier to assemble. In this was the engine, transmission and front suspension and brakes can all be assembled together before the entire asseembly is upfitted to the car as a oner
Title: Re: Why do we have a subframe...
Post by: Webby the Bear on 15 December 2013, 12:10:05
Omega has a front subframeto make it easier to assemble. In this was the engine, transmission and front suspension and brakes can all be assembled together before the entire asseembly is upfitted to the car as a oner

Thanks 2woody....so we have what I would call a ''cross member'' which is like a square supporting the engine.... them a front subframe bolted to that to which the suspension components nail to? :)

sorry for all the posts but I'm trying to get my head round it all and ive got to be honest im struggling with suspension...so many different set ups!
Title: Re: Why do we have a subframe...
Post by: 05omegav6 on 15 December 2013, 12:18:56
The front subframe is C shaped. The cross member being the part of the subframe assembly which joins the two sides together...

This bit of the C... »C  :y

I'm not sure if it makes VW engineers lazy or brilliant, but this Audi Coupe,  http://www.pistonheads.com/ultima/default.asp?storyId=17583  (http://www.pistonheads.com/ultima/default.asp?storyId=17583), had the same subframe front and rear...  :y
Title: Re: Why do we have a subframe...
Post by: Webby the Bear on 15 December 2013, 12:28:00
The front subframe is C shaped. The cross member being the part of the subframe assembly which joins the two sides together...

This bit of the C... »C  :y

I'm not sure if it makes VW engineers lazy or brilliant, but this Audi Coupe,  http://www.pistonheads.com/ultima/default.asp?storyId=17583  (http://www.pistonheads.com/ultima/default.asp?storyId=17583), had the same subframe front and rear...  :y

 :y :y :y

and I trust the subframe and cross member are all replaceable if needed..... just out of interest? :)
Title: Re: Why do we have a subframe...
Post by: 05omegav6 on 15 December 2013, 12:37:44
The front subframe is C shaped. The cross member being the part of the subframe assembly which joins the two sides together...

This bit of the C... »C  :y

I'm not sure if it makes VW engineers lazy or brilliant, but this Audi Coupe,  http://www.pistonheads.com/ultima/default.asp?storyId=17583  (http://www.pistonheads.com/ultima/default.asp?storyId=17583), had the same subframe front and rear...  :y

 :y :y :y

and I trust the subframe and cross member[/highlighted] are all replaceable if needed..... just out of interest? :)
On the Omega, the crossmember is the name given to part of the subframe. The bit that 'crosses' the car. They are the same lump of metal :y

On some cars the crossmember is the subframe, Ford Sierra being a good example. :y

Either way, they are replaceable :y

In the case of the Omega, cradle over the top of the engine to hold it up, separate the struts from the wishbones, undo the drop link/arb bolts, two engine mount bolts, undo the earth strap and six subframe bolts and it should simply fall off...

Best done on a two post lift :y
Title: Re: Why do we have a subframe...
Post by: Webby the Bear on 15 December 2013, 12:44:52
cheers taxi  :y :y :y
Title: Re: Why do we have a subframe...
Post by: 2woody on 15 December 2013, 12:47:34
On the Omega, the front cross mamber is the front subframe. Same component - different names.

Most of the world calls this a K-member, which reflects its shape.
Title: Re: Why do we have a subframe...
Post by: atifn79 on 21 December 2013, 04:12:21
A car sub frame is a structural section of a vehicle, such as an aircraft that uses a distinct and separate structure within a larger body on frame or unit body to carry certain components, such as the engine.