craig1410
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| posted on 26/1/07 at 10:57 PM |
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What sort of engine is it? I'm guessing an iron block V8?
If so then build a Cobra! 
All the best,
Craig.
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Simon
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| posted on 26/1/07 at 11:20 PM |
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Yeah, I agree, if it's cast iron, it will be incredibly heavy - like 5-600 lbs. So something where the engine will be a lower percentage of
car's weight, might be a better option.
Craig,
Have you booked your SVA yet
ATB
Simon
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craig1410
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| posted on 26/1/07 at 11:28 PM |
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quote:
Originally posted by Simon
Craig,
Have you booked your SVA yet
ATB
Simon
You're trying to wind me up and I'm going to remain calm....1......2.......3.....NO I'VE NOT BOOKED MY SVA OKAY????? 
.....4.....5......6...7.8.9.10
Okay, I'm better now. I'm hoping to work on the car this weekend if my wife and kids give me peace.
Cheers,
Craig.
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Angel Acevedo
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| posted on 27/1/07 at 12:59 AM |
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quote:
Originally posted by craig1410
What sort of engine is it? I'm guessing an iron block V8?
If so then build a Cobra!
All the best,
Craig.
Ihaven`t found so much information available for scratch built cobra, don`t think build will go smoother.
thanks 
Beware of what you wish.. for it may come true....
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craig1410
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| posted on 27/1/07 at 11:47 AM |
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Hi,
Okay, if you want to build a Locost with an iron block V8 then you will need to make some changes to the chassis to improve stiffness. Check for posts
by Cymtriks for details. It included changing some of the tubes from 1" x 1" to 2" x 1" around the bottom of the engine bay.
You will probably need to do the same at the top of the engine bay as well. Obviously you will need to ensure that there is enough room in the engine
bay for the engine so I would suggest you go at least 4" wider and probably 2" or more longer in the engine bay. The extra width is mainly
required to allow the engine to go far enough back without reducing pedal space below the minimum.
While you're at it you might want to add a bit of chassis height (1-2" if you need to, to reduce any bonnet bulges. I wish I had added
1" to my chassis height as it would have made life easier.
Obviously, if you go down this road then you will need to make custom body parts and you will need to make each chassis tube to suit rather than
cutting tube angles from a plan. No big deal but certainly more work for you.
In the end, it's do-able but you might be better passing on your iron V8 and either try to pick up an alloy one or look at other engine options.
I'm afraid even I would draw the line at using an iron V8 in a Locost.
Good luck though!
Craig.
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dern
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| posted on 27/1/07 at 04:38 PM |
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There's a lot of nonsense talked about with regards to putting v8s in a seven normally by people who haven't driven one. I had a 4.6 in my
old westfield which put out about 300 brake and about 300ftlb. I was utterly brilliant. Overtaking was effortless, handling wasn't a problem
(just as good as my old xflow westfield) and was fine in the wet. You could spin up the wheels if your throttle control was shite but if that's
the case then what are you doing in a 7 in the first place? The only thing that let it down on track was the gearbox which was a bit clunky but could
go round the outside of elises so if anyone tells you v8 engined 7s don't handle pass them a bung for their arse
R1 (2003 FI) powered Locost in progress
Fireblade/Impreza
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craig1410
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| posted on 27/1/07 at 07:25 PM |
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quote:
Originally posted by dern
so if anyone tells you v8 engined 7s don't handle pass them a bung for their arse
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Stu16v
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| posted on 28/1/07 at 07:50 PM |
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quote:
Originally posted by dern
I was utterly brilliant.
And modest to boot...
Dont just build it.....make it!
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dern
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| posted on 28/1/07 at 09:09 PM |
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quote:
Originally posted by Stu16v
quote:
Originally posted by dern
I was utterly brilliant.
And modest to boot...
Lol, oops... it was brilliant, I was shite
R1 (2003 FI) powered Locost in progress
Fireblade/Impreza
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tks
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| posted on 29/1/07 at 07:21 AM |
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quote:
Originally posted by Simon
"a low reving V8 is a "puller" not a race engine"
Try telling that to Audi and their torquey diesels winning at Le Mans!
------------------------------------------------
BTT who cares what you power it with
I wanted a Rover V8 engine cos I like the sound and the relaxed cruise - which given the congestion on most of our roads is all we can do.
I like the fact I can plant the throttle in any gear (except first, as I don't use it), and blat past anything, though I may have to change down
(from top at 30mph!!) when the Jag diff goes in.
I wasn't building something that will give the german cobblers italian motor a race, I was building a car how I wanted it.
The engine is standard (9.35 c/r), apart from the turbo's and injection, so I'm hoping to keep most of the torque characteristics of the
engine, though, once boost comes in, things should get a little more interesting.
With the Jag diff (ratio 2.88:1), I'm hoping for very good consumption figs (like 35 - 40mpg) on a run.
I may well, once mods are done, go on a trackday or two, maybe even go to the Pod to get some idea of performance. As I said, I'm hoping for
300bhp, and the Jag diff will give a theorectical top speed of 156.
Who knows, if it works nicely, I may bin the 3.5, get a 3.9 and a pair of K04 turbos (presently K03's and may aim for 400 bhp). It's
my car, built how I wanted it.
Like it or not, I don't really care - just so long as you appreciate the effort I put into it!
My next project may well be lightweight and DIESEL, and I want 80 mpg at 80 mph
ATB
Simon
[Edited on 26/1/07 by Simon]
What are revs? For me revs are 6000rpm or more.
Anyway its just what we both say its a personal preference of what we like.
But technically spoken is what this topic whas for, if not forgive me and i was wrong.
The only way to be able to get on the limit is if you have got revs if you better can choose the revs you can always drive as fast as possible. Thats
the reason that a race engine always revs also its the reason wy they opt for a wide torque curve (driveablity) etc..
What i mean to say is that i prefer (for raceing) a 300BHP V8 with 8000Rpm then one with 5500Rpm. in the 8000one i can go with 3000Rpm around a corner
to give me a certain speed next round i coud try 3200
that 200rpm on a lower reved engine means a bigger increase in BHP/Torque/Speed!
For cruising I prefer diesel 2500RPm top gear and 80mph.
Tks
The above comments are always meant to be from the above persons perspective.
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craig1410
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| posted on 29/1/07 at 09:38 AM |
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Tks,
Race engines produce high revs because they are usually have a limit to engine capacity and therefore the only way they can produce considerably more
power is by raising the revs. Remember power is proportional to RPM. This is how an F1 engine produces 850BHP+ out of 2.4 litres.
IMO engine revs is irrelevant, it is average power in the useable band which is important (ie. from the revs just before changing up a gear to the
revs just after the upwards gearchange. If you have a nice fat power curve in this area (which in turn depends on the torque curve being nice and
f(l)at then you won't have any problems making good lap times.
Also, with a torquey engine you have the option of not changing down a gear when you might otherwise need to in a "revvy" engine and still
have useable power. This is particularly handy in wet conditions or if you need both hands on the wheel to correct a slide mid-corner.
As was said above, look at the Le Mans winning diesel if you want proof that low revs is not necessarily a disadvantage...
ATB,
Craig.
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Simon
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| posted on 29/1/07 at 08:17 PM |
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From Wikipedia (on the Audi R10 diesel engine):
"The main novelty of the R10 is its engine: a TDI turbodiesel engine, running on Shell V-Power Diesel. It is a 5.5 L (335.6 ci) all-aluminium
bi-turbo 90° V12, with common rail direct injection of more than 1600 bar (23,206 psi). Its output should be 650 hp (485 kW) (regulated) and 1100 N·m
(811 ft·lbf) of torque, and its usable power band is between 3000 and 5000 rpm. Its benefits are a broad range of usable power, high torque and
economy. Two Garrett TR3076R turbochargers limited by the regulations to 2.94 bar (42.64 psi) absolute breathe through two 39.9 mm intake air
restrictors. It uses the latest Bosch Motronic (MS14) management, provided by Bosch Motorsport, 1600 bar piezo injectors, and makes a low noise for a
race car."
Notice the high revving nature of the engine Similar in fact (if not weight or economy) of a turbo'ed Rover V8
ATB
Simon
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craig1410
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| posted on 29/1/07 at 09:26 PM |
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Interesting article Simon.
Another thing to consider is the fact that it is very difficult to design an engine which will run efficiently at all RPM's, especially if the
RPM range is very wide. You can only really tune exhaust/inlet tract lengths and camshaft characteristics to suit a narrow RPM band, often known as
the "power band". The more power you try to squeeze out of the engine the narrower and peakier the torque and power curves become. VTEC
engines get around this to an extent but at the expense of complexity.
In a race engine this peaky curve is not such a problem because a close ratio gearbox is used to ensure that the RPM never goes very far either side
of peak power. Also, there are often more ratio's available and 1st gear can afford to have a high ratio (like a normal 2nd gear) because you
don't spend much time going slowly.
However, in a road/track car which is sometimes driven slowly in traffic you need to have a sensible 1st gear ratio. Also, the standard spacing
between gear ratio's can be enough to knock a highly tuned engine "off the boil".
With a large capacity, "lazy" engine like the RV8, the engine has not been tuned to a particular RPM range and is able to pull well at all
RPM's. It uses brute force, or cubic inches (no substitute!), to make the power.
So to answer the question of this thread "Rover V8 --- simple power?" the answer is a resounding "Yes!"
Cheers,
Craig.
[Edited on 29/1/2007 by craig1410]
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Simon
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| posted on 29/1/07 at 11:25 PM |
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quote:
Originally posted by craig1410
Interesting article Simon.
So to answer the question of this thread "Rover V8 --- simple power?" the answer is a resounding "Yes!"
Cheers,
Craig.
[Edited on 29/1/2007 by craig1410]
Craig,
Never considered it otherwise
ATB
Simon
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craig1410
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| posted on 30/1/07 at 09:38 AM |
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Simon,
Sorry mate, not aimed at you - that would be preaching to the converted!
Just a general justification aimed at the thread owner.
Cheers,
Craig.
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