Most Bangs per Buck... Choosing your engine.

[Davi]

Slightly inspired by the "best engine" post in GG, and just been having a natter with a chap about the choice of my engine for my project car. He asked why I'd chosen the (very) expensive Audi unit when I could get similar (or better) BHP and torque for less money with many other engines.

Personally my reasoning was size and weight - not that many 2.7ltr engines out there, let alone compact V6's that produce nigh on 400bhp & Nm in standard guise.

Talking further though, he reckoned I could "easily" pick up a V8 that could offer the same figures without adding much size or weight. Only then had no suggestions as to what

Without really wanting to change the engine choice at this stage, but always interested in scoping alternatives (especially when trying to find something as elusive as an RS4 engine) is he right? are there any other seriously compact engines that can offer those sort of figures without attracting the high price tag?

[fuoriserie]

Used V8 from the USA, like fords and Gm, but maybe they are not as compact as the Audi unit.

I would consider Bmw and Mercedes engines , but would be afraid to ask for spare parts........

My heart would go for an old Alfa Romeo v6!!!!!!!!!!!!!!!! just for the sound of it.......its music, but why not a Bmw v6?

I think that, for the most bang per the buck, nothing beats an american v8....

Edited by fuoriserie on Tuesday 19th June 13:58

[Black5]

I guess there is a pretty big argument for a Scooby engine.

Ok, not 400 horses as standard, but achievable and plentiful.

[Mattt]

Most bangs per buck - surely it has to be a Speed Six!!!

[Davi]

fuoriserie said:

My heart would go for an old Alfa Romeo v6!!!!!!!!!!!!!!!! just for the sound of it.......its music, but why not a Bmw v6?

When I started this project, one of the first thoughts was Alfa. I strayed when I saw the performance figures for the Audi... though with hindsight I could have got half a dozen alfa engines and played with them a fair deal to try and get the performance and still had change left over by the look of it!

American V8's... One thing I've never really looked at on these is fuel economy - I know that the RS4 when being driven conservatively does 20-22 urban, 28 on a run - can a yank V8 match that? (I know you shouldn't consider mpg too much on this sort of performance car, but as overall bang for bucks go it is something to factor in!)

[jellison]

Davi said:

fuoriserie said:

My heart would go for an old Alfa Romeo v6!!!!!!!!!!!!!!!! just for the sound of it.......its music, but why not a Bmw v6?

When I started this project, one of the first thoughts was Alfa. I strayed when I saw the performance figures for the Audi... though with hindsight I could have got half a dozen alfa engines and played with them a fair deal to try and get the performance and still had change left over by the look of it!

American V8's... One thing I've never really looked at on these is fuel economy - I know that the RS4 when being driven conservatively does 20-22 urban, 28 on a run - can a yank V8 match that? (I know you shouldn't consider mpg too much on this sort of performance car, but as overall bang for bucks go it is something to factor in!)

Yep. LS will do mid 20's if driven sensibly on a run with the odd blas in there.

[Kirsty5150]

I'd hardly call a yank V8 compact, or light weight! I don't know quite how they compare cost wise though. Juts how compact and ligthweight do you need? If you want 350-400 bhp and not too much torque, turbo a hyabusa engine. The very lightweight (remember no gearbox required, it's already there! ) may well make up for the relative lack of torque. You will need a suitably light car to make it worth it though (<600 kgs ideally). Oh, and you get 12Krpm to play with once you've done a few internal mods.

[grahambell]

Kirsty5150 said:

I'd hardly call a yank V8 compact, or light weight!

Well not compared to a motorbike engine, but the latest LS series Chevy V8s are in some ways more compact than a Rover V8.

Remember being at Marcos once and they had an LS V8 sat next to a Duratec V6 and the LS wasn't much bigger, obviously helped by the pushrod heads.

As for economy, when I had the Monaro on test for PH it did around 30mpg in 6th at motorway speeds.

Would certainly say it's worth considering for your project Davi, especially as both Gardner Douglas and Ultima are using it in mid-engined configuration.

In fact Gardner Douglas supply the LS in the UK under their LS Power arm so might be worth you having a chat with Andy Burrows.

[Kirsty5150]

I didn't realise the LS range was that small! Whilst they may get 30 or so mpg in a monaro at motorway speeds, just how often will that be true in a kit car? I suppose it depends what you're after from the engine. I like lots of revs Bike engines), some want low down gruntyness (V8's etc). A mix is the S2000 lump. It's basicaly a 2 litre bike engine. 9,000 rpm and 250 bhp out of the box. Then supercharge it.

[eliot]

SBC iron and new ally LS1's Uk prices:
http://www.chevcentre.co.uk/Products/ChevEngines/S...

I will have the 572ci big block please...

[jellison]

If you are worried about fuel consumption then LS is maybe not the way then - I get 15 most of the time - but it is taken out mostly for a good blast. S2000 with blower sounds good.

[Davi]

Kirsty5150 said:

I'd hardly call a yank V8 compact, or light weight! I don't know quite how they compare cost wise though. Juts how compact and ligthweight do you need? If you want 350-400 bhp and not too much torque, turbo a hyabusa engine. The very lightweight (remember no gearbox required, it's already there! ) may well make up for the relative lack of torque. You will need a suitably light car to make it worth it though (<600 kgs ideally). Oh, and you get 12Krpm to play with once you've done a few internal mods.

Bike engines are a bit small for my needs, I'll be looking at going well over 400bhp eventually, plus a target weight of around 850-950kg (it's a GT rather than a sprinter)

[Davi]

grahambell said:

Kirsty5150 said:

I'd hardly call a yank V8 compact, or light weight!

Well not compared to a motorbike engine, but the latest LS series Chevy V8s are in some ways more compact than a Rover V8.

Remember being at Marcos once and they had an LS V8 sat next to a Duratec V6 and the LS wasn't much bigger, obviously helped by the pushrod heads.

As for economy, when I had the Monaro on test for PH it did around 30mpg in 6th at motorway speeds.

Would certainly say it's worth considering for your project Davi, especially as both Gardner Douglas and Ultima are using it in mid-engined configuration.

In fact Gardner Douglas supply the LS in the UK under their LS Power arm so might be worth you having a chat with Andy Burrows.

Must admit I didn't realise just how compact the LS engines are - or that it now had an all ally block (weight obviously an issue for me with the iron block)

I'm still planning to go forward with the Audi unit at the moment - I'll continue looking for one until such a time as I have to make a "no going back" decision - but it's certainly something to consider.

The question is though, are we really that short on high performance / tuneavble engines? Whenever I speak to anyone about the project, the first question nearly everyone asks is "why aren't you going for a yank V8?" Personally I'd prefer to keep the displacement down a bit - Performance figures for the Audi are certainly comparable with the lower end small block, and as I'll never be intending to take it to 1000bhp or silly figures it's not going to be unduly stressed. About the only major downsides for me with the Audi unit are availability and price! (which admittedly, are really quite major!)

[jellison]

A race cammed 3.2 Alfa 24V lump would be my choice if you wanted a V6 - they are awesome.

[Davi]

jellison said:

A race cammed 3.2 Alfa 24V lump would be my choice if you wanted a V6 - they are awesome.

what do you reckon the max bhp you could safely push through the Alfa is? (by safely I mean more time on the road than in the garage!) I looked at these before the Audi - it was more the lack of torque that steered me away from them. - oh and the choice of transaxle.

Edited by Davi on Wednesday 20th June 09:47

[jellison]

Davi said:

jellison said:

A race cammed 3.2 Alfa 24V lump would be my choice if you wanted a V6 - they are awesome.

what do you reckon the max bhp you could safely push through the Alfa is? (by safely I mean more time on the road than in the garage!) I looked at these before the Audi - it was more the lack of torque that steered me away from them.

Mid 300's bhp region, way north of 400 if blown - but then blown they are not availible without going after market and very expensive. Torque I guess in 350bhp spec around the 300 mark (about RV8 TVR 500 Torque). But not near a 2.6 TT Audi that has been tweeked to 400+bhp. But you have to campared apples with apples.

You can get a 3.5 big bore kit I think still from AutoDelta for the Alfa (bit out of it not had one for years - 2.5 12V GTV6). They make the the BEST Noise outside of a Nascar (and I have an open piped LS6!).

[Mr2Mike]

Davi said:

The question is though, are we really that short on high performance / tuneavble engines?

Not at all, but European (and Japanese) high performance engines tend to be lower capacity, higher revving and quite complex compared to the US V8's.

If you can accomodate a straight 6 then maybe have a look at: BMW S54, Toyota 2JZ-GTE, Nissan RB26DETT?

[andygtt]

Audi V8 is a good choice.. you should get one for ubder £2k and the are a sweet V8 that revs forever....
They are about 150mm or so shorter than an LS1 etc and a lot lighter as a package when you include the lighter Audi gearbox.

I'd stick with the audi.. or go twin turbo BMW V12

[Davi]

andygtt said:

Audi V8 is a good choice.. you should get one for ubder £2k and the are a sweet V8 that revs forever....
They are about 150mm or so shorter than an LS1 etc and a lot lighter as a package when you include the lighter Audi gearbox.

I'd stick with the audi.. or go twin turbo BMW V12

For some reason I hadn't even considered an Audi V8, Nice call Andy. The question is will it be any easier to locate than the RS4 V6...

LOL Don't think the V12 would quite fit in the available space... though I suppose I could always have the 'box and wheels aft of the bodywork

[jellison]

What is this going in?

Picture please.