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V6, Inline 6 or Inline 5??
KFC - 8/6/12 at 09:17 PM

I don't have the chassis yet as I might need to make changes to the chassis before it's built.

I'm trying to decide on what engine to fit to the "haynes" chassis.

V6? BMW 2.5L or 3.0L or the Fiat coupe inline 5 20v engine?

Obviously it would be much easier to fit the MX5 running gear, engine and gearbox. I just thought if I'm going to build it then do it with style, twin exhaust with that lovely sound of a V6.

I thought the duratec V6 would fit better than a M52 BMW engine, both with standard gearboxes fitted to their engines but the Duratec seems quite heavy, 200kg? Upset the handling too much? :confused:

Any thoughts on the complications of mix matching gearboxes and rear gearbox with diff out of 2000 Audi A6 to try and balance the car better or is it just not worth the agro?

Thanks in advance

Kev

[Edited on 8/6/12 by KFC]

clairetoo - 8/6/12 at 09:43 PM

If you build it Mx5 based , you could use the Mazda KL v6 (can be fitted to the Mx5 'box with an adapter) - smaller and lighter than the Ford Duratec

But then I am a bit biased !

KFC - 8/6/12 at 10:03 PM

quote:
Originally posted by clairetoo
If you build it Mx5 based , you could use the Mazda KL v6 (can be fitted to the Mx5 'box with an adapter) - smaller and lighter than the Ford Duratec

But then I am a bit biased !


Have you had it done??
That sounds good, a bit low on power but a bit of tuning with ecu and exhaust will help. Any ideas if anyone has had an adaptor plate made up and what it would cost? Input shaft issues?

matt_gsxr - 8/6/12 at 10:16 PM

How much power do you need.

Claires solution is cost effective and 200bhp is quite a lot in a 500-600kg car.

KFC - 8/6/12 at 11:10 PM

quote:
Originally posted by matt_gsxr
How much power do you need.

Claires solution is cost effective and 200bhp is quite a lot in a 500-600kg car.


Ah, that's more than enough! I was looking at autotrader to see the power of the v6 in the MX6, it says 163bhp? I use it for info but I suppose it's not always accurate. Is this engine in the MX6 gt? Oh, do you know how much it weighs?

[Edited on 8/6/12 by KFC]

samjc - 8/6/12 at 11:38 PM

Send claire a u2u i think she does bits for kits with the mazda v6. gave me some good pointers

Furyous - 9/6/12 at 07:20 AM

From memory, the M52 engine is also around 200kg but that might not be accurate. It's also rather long at 29" from the pulleys to the back of the engine, and it leans over quite far to the side. I think the 4 pot Duratec was 19" front to back, and I only have about 4" of clear space in front of mine in my Fury. The 2.0 Duratec is 96kg. But you're not after a 4 pot, so that's not entirely relevant. Just gives a bit of a comparison.

KFC - 9/6/12 at 08:49 AM

quote:
Originally posted by Furyous
From memory, the M52 engine is also around 200kg but that might not be accurate. It's also rather long at 29" from the pulleys to the back of the engine, and it leans over quite far to the side. I think the 4 pot Duratec was 19" front to back, and I only have about 4" of clear space in front of mine in my Fury. The 2.0 Duratec is 96kg. But you're not after a 4 pot, so that's not entirely relevant. Just gives a bit of a comparison.


This is good feedback, thanks very much! Think I'll be going for the Mazda 2.5 V6, sounds really good, light and easy mods, just wonder if spare parts are cheap and available off the shelf??

DIY Si - 9/6/12 at 09:02 AM

quote:
Originally posted by KFC
quote:
Originally posted by Furyous
From memory, the M52 engine is also around 200kg but that might not be accurate. It's also rather long at 29" from the pulleys to the back of the engine, and it leans over quite far to the side. I think the 4 pot Duratec was 19" front to back, and I only have about 4" of clear space in front of mine in my Fury. The 2.0 Duratec is 96kg. But you're not after a 4 pot, so that's not entirely relevant. Just gives a bit of a comparison.


This is good feedback, thanks very much! Think I'll be going for the Mazda 2.5 V6, sounds really good, light and easy mods, just wonder if spare parts are cheap and available off the shelf??


What spare parts do you need? I'm part way through fitting The KL and MX-5 box to my Sprite, and have just just bought a head set with bolts for £114 as I needed to open the ports up a little to fit the ITBs properly.

The only weight for the KL I could find online was 176kgs. But that was a fully built engine with exhausts as far back as the cat, so by time you've lost the inlet (which is really heavy), the AC and power steering pumps, I'm hoping to be down to about 140.

franky - 9/6/12 at 09:10 AM

Go for an alloy blocked 3.0 bmw lump, or the 2.8, about 200kg with the gearbox fitted, an easy 220bhp without buying throttle bodies etc. The only lean over at 20deg.

MikeRJ - 9/6/12 at 09:16 AM

The 5 cylinder Fiat Coupe lump is a sweet sounding engine with the potential for a lot of power (the turbocharged version anyway), but it's a heavy old lump. I struggled to remove and refit just the alloy cylinder head by myself, and it's an iron blocked engine that shares the same block design with the 2.4L Fiat/Alfa Diesel so it won't be a light casting.

40inches - 9/6/12 at 09:24 AM

Check out this thread by Claire http://www.locostbuilders.co.uk/viewthread.php?tid=161146

DIY Si - 9/6/12 at 09:35 PM

Might also be worth a look at my Flickr account, as I'm up to 1800 odd photos, with quite a few on the engine and box details.

Flickr stuff here. The drive train section gives details on both the original K series install I had planned, and the work needed to the KL engine. The pics are all viewable in anything up to A3 poster size in case you need any details!

[Edited on 9/6/12 by DIY Si]

b14wrc - 12/6/12 at 11:38 AM

Hi,

Im using the Fiat 20v Turbo engine, and can agree with MikeRJ, very sweet sounding engine! And with a straight trough exhaust and air filter, it will sound ballistic.

Im hoping to run 300bhp which should make it interesting. I can also agree the weight of this thing is pretty heavy. ( Understatment - nearly killed me getting it on the stand!) But then again shouldn't have problems with blowing it up!

What gearbox would you mate this too to get RWD?

Rob

rodgling - 12/6/12 at 11:52 AM

I have a 3.2L BMW engine which I'll be breaking or selling soon. Downside is that it needs some work done to the crank (it spun a shell and started knocking), but this should be doable. Available with ECU/key/immobiliser, loom, manifolds, etc so you'd get 90% of what you need in terms of the engine. PM if interested.

KFC - 12/6/12 at 07:12 PM

Thanks for the offer but I think I'm getting close to a decision, unfortunately, it's not a bmw engine, too long and complicated exhaust around the steering column.
Sorry.

Thanks anyway.


quote:
Originally posted by rodgling
I have a 3.2L BMW engine which I'll be breaking or selling soon. Downside is that it needs some work done to the crank (it spun a shell and started knocking), but this should be doable. Available with ECU/key/immobiliser, loom, manifolds, etc so you'd get 90% of what you need in terms of the engine. PM if interested.

spiderman - 16/7/12 at 09:08 PM

Have been looking into v6 motors myself and have narrowed it down to 2, Vauxhall Omega 115kgs and Jaguar 100kgs. I do not know how accurate the figures are and I suspect that is without ancills and gearbox. The Jag is an all alloy motor and the Vauxhall one has an iron block, both are available fairly cheaply as complete cars. Just thought I would throw them into the mix just to confuse the issue.

rodgling - 16/7/12 at 09:37 PM

Another option from left-field: flat 6. Boxster engine and gearbox, already the right configuration for a mid-engined car, right sort of power, lovely noise, great weight distribution... I really want to build a car with one of these in.

KFC - 16/7/12 at 10:21 PM

quote:
Originally posted by spiderman
Have been looking into v6 motors myself and have narrowed it down to 2, Vauxhall Omega 115kgs and Jaguar 100kgs. I do not know how accurate the figures are and I suspect that is without ancills and gearbox. The Jag is an all alloy motor and the Vauxhall one has an iron block, both are available fairly cheaply as complete cars. Just thought I would throw them into the mix just to confuse the issue.



I think those figures are way out. Those engines are about 200kg fully dressed. I've seen some V6's quoted 170kg but again, that's probably fully dressed.
I know that Carol on here has weighed the Mazda MX6 2.5 V6 bare, as in, all auxiliaries off, no flywheel, intake manifold, exhaust manifold and dry. Weighed in at 110kg.

If you're planning on putting a V6 in a locost - westfield type of car, the problem I've found is, where the front of the engine would naturally sit is near dead on a cross bar that is about 700mm from the bulkhead, the width is 627mm. I found that most DOHC engines are quite wide and won't fit. I would love to put in a 3.0 V8 BMW engine but measures 700mm across the widest part of the front of the engine, ie, the heads.

I also found that parts were rare for Japanese V6's and the Jaguar, Alfa 2.5 V6 are expensive. The Rover 3.5L V8 is still in production and loads of parts available. Doesn't stop me from thinking of ways of fitting the BMW 3.0L V8, it sounds so different, I like small capacity engines with lots of cylinders.


The Rover 3.5 is the favorite at the moment as it's only 500mm across the heads but I keep thinking of was to make the BMW engine fit.

KFC - 16/7/12 at 10:25 PM

quote:
Originally posted by rodgling
Another option from left-field: flat 6. Boxster engine and gearbox, already the right configuration for a mid-engined car, right sort of power, lovely noise, great weight distribution... I really want to build a car with one of these in.



Nice but wrong sort for these cars. The westfield - locost type are balanced just right with the engine / gearbox configuration. 50/50 weight distribution.

rodgling - 16/7/12 at 10:34 PM

Wrong for a 7 type car, sure, but so right for an Atom style mid-engined car, surely? It would end up a bit longer than an Atom or similar I suppose, but it could work. By weight distribution I mean that the weight would be very low down, not the front-rear distribution.

DIY Si - 17/7/12 at 01:50 PM

It's Claire, not Carol by the way.

But I'm glad she has weighed it, as it saves me the bother of doing so! And it's also lighter than I thought, and lighter (just) than the A series it replaces.

ss1turbo - 13/8/12 at 04:05 PM

I think the Omega engine tips in at just over 200kgs with gearbox and being a 54 degree V6 is narrower than the Rover V8 (I know this because you can't fit a RV8 in a Scimitar GTE without surgery to the bulkhead; the Omega lump fits ).

210bhp with cats (so hopefully more without) out of the box and no messing with gearbox converters....gearbox is a bit chunky, but if an MT75 fits, so will the R25/R28. The 2.5 isn't to be sniffed at - 170-odd standard and 190-ish with just a set of 3.0 cams fitted...and the bits are (relatively) cheap.

Nickp - 13/8/12 at 05:03 PM

quote:
Originally posted by KFC
Thanks for the offer but I think I'm getting close to a decision, unfortunately, it's not a bmw engine, too long and complicated exhaust around the steering column.
Sorry.

Thanks anyway.


quote:
Originally posted by rodgling
I have a 3.2L BMW engine which I'll be breaking or selling soon. Downside is that it needs some work done to the crank (it spun a shell and started knocking), but this should be doable. Available with ECU/key/immobiliser, loom, manifolds, etc so you'd get 90% of what you need in terms of the engine. PM if interested.


I've trial fitted an M52 to my Haynes chassis no probs, just a few challenges Yes it's long, but goes in OK if you get the back of the head right back to the bulkhead. Also, BMW were kind enough to make the exhaust manifold flanges symetrical meaning you can turn them upside down and pop the downpipe out of the side of the bonnet missing the steering column by a country mile The alloy blocked engine seems to be about 170kg fully dressed depending on where you look, so 200kg with gearbox sounds about right. I picked mine up complete (gearbox, ecu etc) for £150 delivered, so at about 200bhp bang for buck I don't think it can be beat.