Rwd V6 Space Frame Mounting Points

[M_R_205 5 1 Cars]

Iv started welding together a space frame to mount a V6 in the back of the pug, im making it in such a way that the space frame is compleatly seperate from the car and therfore can easily be bolted in and out of the car, along with the engine and all the suspension,

 

Any way on with my plea for advice, Where would be the best place to mount this subframe?

 

My original though was to make it into a roll cage but i want it to look quite standard looking from the outside and front seats (just dont turn around.....)

 

i was thinking of welding in a plate to these two locations and then bolting the space frame to them

http://i91.photobucket.com/albums/k296/con...ne/DSC00020.jpg

http://i91.photobucket.com/albums/k296/con...ne/SNV31107.jpg

 

All ideas thoughs and advice greatly welcome,

 

Cheers

Paul

Edited July 29, 2008 by cybernck
image filesize over allowed limit!

[bren_1.3 1]

i dont think its a good idea to be honest.

 

your talking about stressing an area which were never designed to take any, even from the rear suspension. and now your talking about welding in a couple of plates here and there to take the weight of a space frame/suspension/gearbox/v6 engine plus gubbins, and then all the vibrations and transmission/engine loads, as you presumably give it death down the road...

 

call me pessimistic, but i have an image of the car tearing in half.....

 

you need to look at what cybernck did on his in welding in the front section of a 205 to the rear. or the guy who was building the twin v6 monster, i think that was a space frame job. maybe take inspiration from autocross cars and see how they do things?

 

i cant ever imagine this whole scenario being a case of bolt in bolt out. the rear of a 205 just simply isnt strong enough IMO. (and in looking at the photos again it would seem that youve cut out the rear beam mounting points. the strongest parts on the rear) they wither and die in any form of car-on-car accident.

Edited July 30, 2008 by brens_1.9_wide_arch

[brianthemagical 1]

If the beam mounts are still there then attatch to them and seat belt mounts as a start. I'd think trying to have forward motion through the floor, as in the edge pushing it and the under the floor and the rear quarters for ups, try and put all forces through a joint or into the edge of a panel, not the center or upsupported parts of panels and then use as much attachment as poss, even if it's a welded in frame that the is welded in then bolted to. Just try and think about what the froces are doing and where they're going.

[projectpug 0]

How about a bike engine ? A lot lot lighter than a V6 and be comparable to the v6 in terms of power / weight ratio.

[welshpug 1,627]

How about a bike engine ? A lot lot lighter than a V6 and be comparable to the v6 in terms of power / weight ratio.

 

 

but not torque, and having to rev the knackers off one to get the thing moving.

 

I think it would be easier to get the front end of a 406 and trim all the unwanted parts off, similar to what Cybernk did, and the same as a Lad up in lancashire has done with a 106.

[M_R_205 5 1 Cars]

This is the sort of thing i was thinking of but with a big ass v6 in there and double wishbones

 

http://www.pistonheads.com/gassing/topic.a...=277317&i=0

Edited July 31, 2008 by M_R_205

[bales 1]

Without wanting to sound a bit arsey do you think that if you are having to ask these sort of questions about the basic fundamentals of the project already then perhaps you are taking on a bit more than you can chew...

 

IMO the spaceframe bit is relatively easy, I designed the chassis for the Formula Student car for 2 years at uni and aslong as you understand the basic principles of a spaceframe and have an idea of what you want to achieve and how you are mounting your engine and suspension then it is doable...Assuming you know what you are doing and have a good understanding of the difference between strength and stiffness and the fact that sticking big thick bits of metal in doesn't actually make any difference unless they are welded to the right places...

 

I would say the hardest bit, as has been mentioned is finding somewhere stiff enough on the shell to mount your space frame to. As soon as you cut any of the floor away you are losing all the stiffness that the shell provides with it being a monocoque so I really really doubt that cutting the floor out and bolting a cradle for the engine into the areas you have indicated would provide a safe or particularly drivable car!

 

If it was me doing it (and I have thought about it occaisonally) there is two ways I would approach it, the standard route seems to be bolting the front end of another car in and then you have all the suspension mounting points and you have a proper subframe that will give it some strength and be slightly easier to mount to the rear of the car.

 

Or the second route if you want to do a spaceframe would be to do it as an extension of a rollcage, where you derive your stiffness from the mounting points of the cage in the car and then modify it to suit the suspension and engine mounting points etc....which is not going to be a 2 minute job.... and so you dont really have a 205 anymore as you arent using the shell for strength so its almost like a silouhette type racer...

 

IMO

[M_R_205 5 1 Cars]

Without wanting to sound a bit arsey do you think that if you are having to ask these sort of questions about the basic fundamentals of the project already then perhaps you are taking on a bit more than you can chew...

 

 

IMO the spaceframe bit is relatively easy, I designed the chassis for the Formula Student car for 2 years at uni and aslong as you understand the basic principles of a spaceframe and have an idea of what you want to achieve and how you are mounting your engine and suspension then it is doable...Assuming you know what you are doing and have a good understanding of the difference between strength and stiffness and the fact that sticking big thick bits of metal in doesn't actually make any difference unless they are welded to the right places...

 

I would say the hardest bit, as has been mentioned is finding somewhere stiff enough on the shell to mount your space frame to. As soon as you cut any of the floor away you are losing all the stiffness that the shell provides with it being a monocoque so I really really doubt that cutting the floor out and bolting a cradle for the engine into the areas you have indicated would provide a safe or particularly drivable car!

 

If it was me doing it (and I have thought about it occaisonally) there is two ways I would approach it, the standard route seems to be bolting the front end of another car in and then you have all the suspension mounting points and you have a proper subframe that will give it some strength and be slightly easier to mount to the rear of the car.

 

Or the second route if you want to do a spaceframe would be to do it as an extension of a rollcage, where you derive your stiffness from the mounting points of the cage in the car and then modify it to suit the suspension and engine mounting points etc....which is not going to be a 2 minute job.... and so you dont really have a 205 anymore as you arent using the shell for strength so its almost like a silouhette type racer...

 

IMO

 

Thanks for your comment and dont worry i dont think you being arsey at all, The guys at work are being arsey

 

Yes i have deffinatley bitten off more than i can chew!, the main reason i asked about the mounting point as apposed to diving straight in with rollcage extension idea, is a friend pointed me towards the Z cars site and asked if i realy needed it... after much deliberation and chin scratchin i have decided to follow the origional idea of basicalyy extending a rollcage but i will also be mounting it to the seat belt mounting poits for a little extar support.

 

im going to pop over the garage tonight and take a few photos which il try and explain a little better...

 

Paul

[brianthemagical 1]

As a side note on the doubts of using a cage, do you think pug designed the shell to be strong enough to take two engines and would you want to drive such a car as your building with no cage? I'd say extending the cage is the right idea, then you can brace the shell to the cage for extra stiffness of the two.The rear space frame should add all the stiffness you need, or could if designed well, that the removal of the floor removed.

Edited July 31, 2008 by brianthemagical

[Batfink 201]

but not torque, and having to rev the knackers off one to get the thing moving.

 

I think it would be easier to get the front end of a 406 and trim all the unwanted parts off, similar to what Cybernk did, and the same as a Lad up in lancashire has done with a 106.

 

dont most modern bikes have just as much torque as old cars like ours, its just high up in the rev range...

[Rippthrough 98]

dont most modern bikes have just as much torque as old cars like ours, its just high up in the rev range...

 

 

About 85lb of torque, people forget that that a bike engine 'screaming' along at a 3k cruise is barely ticking over.

Scared of using the power available I think, most bike engines these days produce 80% of max torque from about 5k to 14k, nothing wrong with that kind of powerband!

[dirtdog 4]

seen this whilst trawling the net, sounds crazy and doesnt look like it goes bad either

MK2 Escort with bike engine

[projectpug 0]

If i was going to use a bike engine it would be one of these two,

 

Suzuki Hayabusa-Preferably

Power = 158.0hp @ 9750 rpm

Torque = 98 lbft @ 7000 rpm

 

Kawasaki ZX12R

Power = 160 hp @ 10250 rpm

Torque = 91 lbft @ 7750 rpm

 

Both of these engines produce decent torque right from the off so perfect . They can also be charged to increase the power/torque dramatically. Obviously they come on song around 7k where they produce strong torque considering the capacitiesof the engines .

[tom_m 0]

seen this whilst trawling the net, sounds crazy and doesnt look like it goes bad either

MK2 Escort with bike engine

 

thats definitely using some sort of forced induction though

[welshpug 1,627]

it does indeed - http://www.situne.no/index.php?id=3&carid=1

[Rippthrough 98]

If i was going to use a bike engine it would be one of these two,

 

Suzuki Hayabusa-Preferably

Power = 158.0hp @ 9750 rpm

Torque = 98 lbft @ 7000 rpm

 

Kawasaki ZX12R

Power = 160 hp @ 10250 rpm

Torque = 91 lbft @ 7750 rpm

 

Both of these engines produce decent torque right from the off so perfect . They can also be charged to increase the power/torque dramatically. Obviously they come on song around 7k where they produce strong torque considering the capacitiesof the engines .

 

 

ZX14R........

190+ bhp @ 9500rpm

113 lbft @ 7500rpm

 

And a decent exhaust system and power commander will take them to about 215bhp.

 

Sorted!