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moego
30-11-05, 02:26 PM
I am not a motor engineer, but can anyone tell me if it would be possible to use a Porsche V8 in a new build, and if so which kit would be the best?

Hope I hav'nt just embarassed myself:confused:

John

Robin427
30-11-05, 03:05 PM
You got the "8" bit right... I don't know anything about that engine, but I've seen people with Jaguar V12s shoe-horned in so if it is smaller than that, I can't see why it wouldn't be possible

Which kit would you be thinking of? It would certainly sound unique...

TonyD
30-11-05, 03:07 PM
Whats the width across the top of the cylinder heads ? Any wider than 750mm and you will be having a problem getting it to fit in any kit.

I like the thinking though!!

Cheers,

Tony:thumb:

moego
30-11-05, 06:47 PM
Thanks Tony

I'm pretty sure it's no more than 750cm but there are alot of other bits around it that would need to be tucked away. As to the Kit choice I have a blank canvas as I don't think that it will fit in the sumo 11, and anyway I would like to build a beast from scratch so I am open to any sugestions:-}

John:rolleyes:

mylesdw
30-11-05, 06:53 PM
Doesn't the 928 have a transaxle gearbox? If so there may be an issue physically fitting it in to the space behind the seats. Like the sound of it though!

moego
30-11-05, 06:59 PM
Thank Myles
I knew it wasn't going to easy:o

TonyD
30-11-05, 09:16 PM
If the main bulk of the engine is less than 750mm across the heads and you can either fit a normal gearbox with an adaptor plate or adapt the rear of the chassis to accept the porsche transaxle you could be onto a solution.

How is the porsche tranaxle mounted in the standard car? Could the mountings be adapted to mate with a chassis normally made to accept the Jag or Sierra rear end?

Nothing is insurmountable if you can throw enough ingenuity or money at the problem..........

Nice to see someone else thinking outside the box.......

Cheers,

Tony :thumb:

demus
02-12-05, 12:25 PM
Be nice to use the Porsche rear suspension too, now that would be a head ache!!

I presume the clutch is still on the flywheel, if this is in some sort of bell housing maybe it would be too much trouble to make an adaptor plate as Tony said.
Nice engine though, plenty of torque if I remember rightly??

DiggleBBC
02-12-05, 12:52 PM
I would just like to suggest that if anything goes wrong with the Porsche engine, that the fixing of it could be costly. Chevy V8s have been made for donkeys years, and in some numbers, so that there is quite a large support industry around them. Porker v8? Sucks air in through teeth, it'll cost ya.
Anyone else remember the Top Gear challenge to buy a Porsche for 1500 or so? The V8 kept on dumping fluids from every orofice.

moego
02-12-05, 01:20 PM
Thanks for the reminder Peter, I have experienced first hand the excitement of Porsche bills, and have been a member of the owners club whilst owning and driving a 928 S2 back in the 80's, If I can find the right Kit more than likely a Jag running gear base, I will rebuild the engine and take my time with the build as I would enjoy the challenge and also I didnt build my Sumo (although we are having to do a lot of rebuilding and correcting):confused: So a build from scratch very exciting:rolleyes:
The electrically operated Porsche lounge recliners would look brilliant in my office:D
Be positive:thumb: :thumb:

apearce
02-12-05, 02:10 PM
Re the transaxle, I think it would be easier to make up a bellhousing and flywheel and fit a tremec or similar box up front than to alter the kit's chassis to accept the porsche transaxle. sumo chassis probably isnt up to the power you are talking about and dax/ak chassis would require massive alteration to create a gaerbox sized hole at the back (plus without the jag diff, you'd have no rear suspension arms)

If you like a challenge and a cheap plentiful engine, you can snap up a 1980's merc s class for a few hundred quid these days - 3.8/4.2/5.0 and 5.6 v8 engines; all alloy; mechanical injection (simple, no ECU) - the only problem is mating a manual box to it again. p.s. only 1 OHC per bank too so its narrower (isnt the porker a quad cam?).

cheers
Andy

TonyD
02-12-05, 02:44 PM
Andy,

Having run a tape measure over the Merc V8's the killer is the cam covers, they are as wide if not wider than 4 cam engines....... I couldn't get a Merc V8 to fit in a Cobra when I was first looking, which is a shame cos the engines are relatively inexpensive and extremely robust.

If guys are looking for a chassis to take some exotica there's only one company I would choose, more than helpful and welcome the challenges I pose them.....yep AK again!

Cheers,

Tony :thumb:

moego
02-12-05, 02:52 PM
Thanks Tony thats the route I was thinking of :thumb: Still alot of thinking to do:rolleyes:

moego
04-12-05, 05:23 PM
Hi Tony who to speak to at AK:thumb:

TINKA
04-12-05, 05:36 PM
Ken is the Man to ask for:thumb: :thumb:

Purple AK
04-12-05, 05:37 PM
Speak to Ken (Daddy AK) 01733 267633 ;) :thumb:

moego
04-12-05, 05:39 PM
Speak to Ken (Daddy AK) 01733 267633 ;) :thumb:Thanks guys on to it the morrow:thumb: :thumb:

Purple AK
04-12-05, 05:45 PM
Ken is the Man to ask for:thumb: :thumb:
Sorry Martin. Didn't see you there :o

TINKA
04-12-05, 05:45 PM
Tobe honest John if you tell Ken exactly what you want He will probably just ask you to drop him your engine off and tell you to come back once he has modified the chassis and foot wells ( if this is necessary ) and pick it up once he has done all this. Don't think any other kit firm will offer you this sort of service. I have been to AK's premises on many occasions and seen him doing similar things for example A BMW V8, 2 x Lexus V8s and a new Ford Mustang V8 which is a lot wider with the overhead cam's, I think Ken loves a challenge sometimes instead of just turning out standard kits.
HTH

Good luck Martin

TINKA
04-12-05, 05:47 PM
Sorry Martin. Didn't see you there :o


No worries Chris:thumb: makes a change for my fingers to be quicker than someone else's :D

moego
04-12-05, 05:50 PM
I think I love you guys. Thanks it may be coming together now:thumb:

mylesdw
04-12-05, 07:16 PM
Keep it up guys! It is always interesting to hear about people putting unusual engines into their Cobs. In this part of the world the Lexus engine is quite a common choice. I got chatting to a guy the other day with two of them in his jet boat. He reckoned they are SO much stronger and more reliable than a SBC!

TonyD
04-12-05, 11:42 PM
Keep it up guys! It is always interesting to hear about people putting unusual engines into their Cobs. In this part of the world the Lexus engine is quite a common choice. I got chatting to a guy the other day with two of them in his jet boat. He reckoned they are SO much stronger and more reliable than a SBC!

It was looking at some Aussie Cobras ( to be more exact Ozvenom's Cobra) that got me thinking about the Lexus route. Hence now I have two Lexus V8's going into two AK kits in my garage, sharing space with the Beemer engined beast.

The Mrs thinks that one Cobra in the garage is acceptable, three is being just plain greedy !

I must say that now I've had them apart the Lexus engine is a delight to work on and the design and thought thats gone into it is first class........Now I just have to get at least one of the buggars built and SVA'd for the Le Mans Classic....

Cheers,

Tony:thumb:

apearce
08-12-05, 03:07 PM
Wouldnt it be great if there was an all alloy ohc engine which was robust, had simple electrics, didnt have to be imported, was available in plentiful supply for a few hundred quid, fitted easily into a dax chassis, mated with a proven 5 speed manual (also available for a few hundred quid), made 300bhp straight out of the box or 450 bhp with mild mods because (unlike detriot pig iron) it was designed for racing and revs to 7500rpm on standard lubrication.

OH yes, the jag V12. But then its not a V8. Its sort of inverted snobbery when you think about what engine you get in the flagship cars of BMW, Merc, Rolls Royce, Ferrari, Lamborghini (oh and Michael Shumacher's race car).

The bloke I bought my corvette engine from cant believe Im about to take out a v12, especially after he saw the dry tarmac donuts it can pull and the spine chilling noice on full chat (yes torque and noise are not the exclusive preserve of v8s) - i must be mad, pandering to fashion, oh well

cheers
Andy

mylesdw
08-12-05, 05:38 PM
Wouldnt it be great if there was an all alloy ohc engine which was robust, had simple electrics, didnt have to be imported, was available in plentiful supply for a few hundred quid, fitted easily into a dax chassis, mated with a proven 5 speed manual (also available for a few hundred quid), made 300bhp straight out of the box or 450 bhp with mild mods because (unlike detriot pig iron) it was designed for racing and revs to 7500rpm on standard lubrication.

OH yes, the jag V12. But then its not a V8. Its sort of inverted snobbery when you think about what engine you get in the flagship cars of BMW, Merc, Rolls Royce, Ferrari, Lamborghini (oh and Michael Shumacher's race car).

The bloke I bought my corvette engine from cant believe Im about to take out a v12, especially after he saw the dry tarmac donuts it can pull and the spine chilling noice on full chat (yes torque and noise are not the exclusive preserve of v8s) - i must be mad, pandering to fashion, oh well

cheers
Andy

Yes, this anti V12 thing puzzles me too. When Dax brought it out, people saw it as 'the ultimate Cobra'. American V8s are very crude by comparison.

Antony
10-12-05, 08:17 AM
I reckon the sound of the Aston Martin DBR9 Le Mans car that ran on Top Gears race track 1.08minute lap, ie 10 seconds quicker than the Porsche Careera V10 620bhp car was absolutely fantastic, I assume that has a V12 in it.

The Jaguar V12 is a good engine but heavy and hard to make over 600bhp, I have a Ford alloy engine making 675bhp which is a detuned Nascar engine, this engine has a lot better quality parts to make it live compared to a factory type Yankie V8 engine, but I guess they have been around since the early 1960's so compared to modern engine technology which has gone all modular etc, the old SBC and SBF are antiquated, but I would have to say a V8 is more in keeping with the Cobra image!

mikey
10-12-05, 10:17 AM
Keep it up guys! It is always interesting to hear about people putting unusual engines into their Cobs. In this part of the world the Lexus engine is quite a common choice. I got chatting to a guy the other day with two of them in his jet boat. He reckoned they are SO much stronger and more reliable than a SBC!

From what I have been told, I think you will find that the more modern engines rely on a greater Nickel content etc if cast to give them strength. This means they can be made lighter, but they dont design them necessarily to be stronger, they design them to fit the application. I think you will find that the Ford and Chevy small block units are over engineered but they are also very heavy. This means that you will probably have similar strength, but in a lighter set up. But if you want that you can go for the Dart and Mowtown Smallblock set up which can take awesome power in a racing application. Horses for courses really.

I think the main reaso people choose the Chevy smallblock is the ammount of power you can get for the cost.

By the way, just to let you know, the SBC was deemed to be one of the most reliable units ever built (Discovery Channel). Apparently they used to use the series 1 in the desert and they coped with sand etc where others broke down. They put much of this down to the oiling system which was revolutionary in its day.

I run a beemer with all the electronis wizadry, but from a gut feeling I think the SBC I have would be chuntering on long after the beemer is worn out. They are just bullit proof

Really do like the idea of a Porsche engine though - quite an engineering feat I would think.
Mike

Robin427
10-12-05, 05:32 PM
I've got an LS1 - the newer variant of the SBC... haven't blown it up yet!!

mikey
11-12-05, 10:37 AM
By pure coincidence the New Zealand Jet Sports Championship was on Motors TV yesterday, The leaders were all using Small Blocks ??

I'd luv a go at that though - nutters or what. 0-100 in 4 seconds.
Mike

mylesdw
11-12-05, 08:39 PM
By pure coincidence the New Zealand Jet Sports Championship was on Motors TV yesterday, The leaders were all using Small Blocks ??
Mike

Definitely the engine of choice for the racers, aluminium blocks, Brodix heads etc are popular but like any race vehicle they only have to stay together for the duration of a race. The chap I was talking to was running a jet boat operation for tourists, running the boat hard several times a day 7 days a week during the season. It is VERY demanding on the engines since they spend long periods at or near maximum power which cars hardly ever do. His experience with the SBC was that the cranks break sooner or later in this application but that the Lexus engines just kept going.

427scr
12-01-06, 04:32 PM
I recently sold some rover V8 bits to a bloke who was putting a Rover into a Porsche 928!

He said that the Porsche 928 was so expensive to repair that it was easier and cheaper to stick a Rover in and throw away the porsche V8.

he might have been a pipe dreamer, but I didn't care as he was buying my bits.

This sort of backs up the relative cost of traditional V8's over exotics like the porsche, Audi, Merc etc. Is it worth the hassle?

Mark.