rallyslag
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 posted on 27/9/02 at 08:53 PM |
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Whats gonna be the best donor for my yank tank
Ok so as most of you know im building a locost with a chevy v8 with the widened mcsorley chassis
whats going to be the best donor for me?
i assume im going to need a wide axle and a strong propshaft to take the power?
will a sierra be suitable? as they seem to be cheap and easy to get hold of
what model will i need to look at getting?
i want one that has powersteering that i could use
Old chinese proverb: "If a man speaks in a forest, and no woman hears him, is he still wrong?"
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dashin_dave
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| posted on 29/9/02 at 05:57 PM |
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given the torque of a 350, i'd give the sierra a wide birth, i can envisage that diff lasting until you first dump the clutch at 6 grand. if i were
you, i'd probably be considering a jaguar xj6/12/s donor, which you can get cheap enough and offer you a more heavy duty diff, and 4 wheel disks,
which you will certainly want with a 350 powered locost. you can also pick them up pretty bloody cheaply in the UK, especially if you go and grab one
thats already been stripped of its engine/box ect, since you dont need them.
if you dont want to screw with IRS, or are building a firebreathing engine, you'll need a ford 9", aka, diff a la unbreakable. could source one from
a ford f-XXX, or fairlane LTD ect, probably pretty hard to get hold of in the UK though, especially at a good price.
in case you didnt read my other post, for gearboxes, a t5 isnt bad, a t56 even better, but if you build a stomper of an engine, you'll need to go for
a manual valve body auto, like a worked powerglide or t400.
have you considered what your actually going to do to this engine??
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interestedparty
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| posted on 29/9/02 at 07:16 PM |
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Having experienced the weight of a set of Jaguar bits, it is my opinion that for a Locost type car they should be avoided. If you don't agree, try
finding a Jaguar diff and pick it up, the weight is outrageous.
GD cars use sierra bits in their 'euro' Cobra chassis, which would normally be fitted with a US V8, so maybe they would be OK for a Locost car, I
doubt if you would get the traction necessary to severely stress the sierra rear end unless you used competition wheels/tyres
John
As some day it may happen that a victim must be found,
I've got a little list-- I've got a little list
Of society offenders who might well be underground,
And who never would be missed-- who never would be missed!
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rallyslag
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| posted on 29/9/02 at 07:17 PM |
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i know its gonna be pushing stupid amounts of power with a mad max type supercharger 
ill take a look around the scrappys and see if i can find any jag axles
i wanna try and keep things as simple as possible suspension wise if i can
Old chinese proverb: "If a man speaks in a forest, and no woman hears him, is he still wrong?"
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Jon Ison
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| posted on 29/9/02 at 08:02 PM |
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I would'nt worry about the back end, you won't get the traction to cause any damage.....sierra will be fine..... 
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dashin_dave
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| posted on 29/9/02 at 08:30 PM |
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*shrugs* maybe i'm wrong on the diff...
with regards to the cobras though.. current AC cobras actually come with the australian 5.0 windsor engine, umm, well, not quite, its actually made in
canada, but it is sourced from the ford australia company, and is aussie spec (i'm pretty sure...)
it is only rated at 165kw, or 220bhp with similar torque figures in ft-lbs, which isnt over the top. in australia the engine is used to power ford
fairlanes, so its no racebeast. a blown 350, on the other hand, i'd expect to be in the region of 400bhp+, which, even with traction issues in a
light chassis, i'm not sure i'd trust a diff that was designed for a 4/6cyl. experienced locost builders probably know better though.
with regards to your engine, i'm not sure what sort of budget your looking at building it on, but if you want to keep things cheap, here is a few
hints:
with regards to your supercharger, GM used these for cyl scavenging on 2 stroke diesils of yesteryear, so if you start poking around truck and plant
wreckers, there is a bit of a chance you'll find one on the side of some big diesil in some rusting hulk and will get it for next to nix. at that
stage, i'd get it inspected by someone who knows roots blowers, then start hanging around the drags and chat to a few mechanics ect, coz you'll need
a set of pulleys for it to run on a chev, and carb plate + end plate, and an intake manifold. if your nice, you'd probably be able to get them pretty
cheap. then you need to rebuild the donk with a set of low compression forged slugs, or at least flat tops if your on a budget, moly rings and chevy
X/pink rods. if your buying this 4 bolt mains block, that'd be good, plus a steel or nodular crank. get the heads fitted with a set of 2.02" and
1.60" valves and depending on your budget, a heap of porting. crane, crow, C.O.M.E and others all have specific blower cams, so buy one of those, or
if not, get a VERY mild cam, since you want MINIMAL valve overlap, coz that just blows your supercharged mix out the exhaust, then get a set of decent
pushrods and maybe roller rockers and then your prettymuch in business. oh, and a pair of say 650 mechanical secondary holleys. get rebiult ones, just
as good, 1/3 the price of new ones. if your budget permits, the sky is the limit, a 383 stroker steel crank, expensive forged conrods and custom
pistons wouldnt be out of place, along with a new B&M 6/71 blower kit, which would probably set you back at least 2000 quid alone.
oh, and if you are going to run one of these, a race preped manualised automatic is the only real option. and a high stall converter.
hope this has been of some assistance
dave
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Simon
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| posted on 29/9/02 at 09:45 PM |
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Someone on here has a Routemaster doubledecker, perhaps you could use the rear axle of that.
ATB
Simon
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chrisg
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| posted on 29/9/02 at 09:50 PM |
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Hands off my donor, Simon!
Cheers
Chris 
Note to all: I really don't know when to leave well alone. I tried to get clever with the mods, then when they gave me a lifeline to see the
error of my ways, I tried to incite more trouble via u2u. So now I'm banned, never to return again. They should have done it years ago!
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merkurman
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| posted on 30/9/02 at 02:34 AM |
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I would run a ford 8.8" IRS diff since they are pretty cheap and very easy to build up. BTW a small block ford is 90 lbs lighter then a 350 chevy.
smaller too. but with a chev Iwould look into running a built 700r4 tranny so I could have a overdrive. but I am a yank so a highway gear is a very
needed item. good luck getting all that under the bonnet. plus why a 350? a chevy 302 would be great in locost.
nick
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rallyslag
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| posted on 30/9/02 at 02:57 AM |
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well the 350 came along on my quest for somthing big powerfull and more than likley quite dangerous with me behind the wheel and for the right
price
its not really gonna be used much for road use but i will get it SVA'ed anyway
Old chinese proverb: "If a man speaks in a forest, and no woman hears him, is he still wrong?"
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Robin Hood
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| posted on 30/9/02 at 05:41 AM |
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If memory serves Jag back axle - if old enough - has inboard discs which help to reduce (!!) the sprung weight but are a nightmare to get to if
you're trying to work on the discs or calipers. Mr Gusterson seems to know more about Jags tho.
I'm pink therefore I'm Spam
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interestedparty
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| posted on 30/9/02 at 08:19 AM |
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any xj6 series 1,2 or 3 (XJS even better, LSD as standard)will have inboard rear discs, trouble is, unsprung weight should be considered as a ratio
i.e. sprung/unsprung weight. In a light car the weight of the Jaguar components is going to be a real problem. I'm not saying that it would be
impossible to fit to a locost,(anything is possible with enough effort) but I am saying that there are better ideas.
John
As some day it may happen that a victim must be found,
I've got a little list-- I've got a little list
Of society offenders who might well be underground,
And who never would be missed-- who never would be missed!
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dashin_dave
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| posted on 30/9/02 at 04:52 PM |
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isnt there reliability issues on t700r4s with big hp engines???
i was going to use one at one stage and was told that the converter lockup for overdrive was an easy bust in big hp installs.
ford 8.8 irs, what were they used in???
with the unsrung/sprung weight ratio, wouldnt that be helped by a 600lb(?) engine, a bulky slushbox, and ancillaries like powersteering?
oh well, i dunno... what other cars available in the UK used big power engines. what do TVR use?? hmm... given tvr reliability issues, maybe thats not
a good question...
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VinceGledhill
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| posted on 2/10/02 at 10:13 AM |
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I was going to build a Pilgrim Sumo cobra but ended up building an AK.
When you talk about cobra replicas then Jaguar is the way to go for running gear and differentials.
I would recommend going the ford Granada route. I've been using the cobra club website for the past year during my build and have never seen anyone
reporting problems with the Pilgrim Sumo and their ford running gear. Pilgrim prefer the Granada to the Siera.
On the program "a car is born" where he builds a pilgrim sumo is fitted with Siera running gear and a 350 chevvy there's no problems. Apparently
the car is still running.
If there was a real problem with this running gear being "ripped to bits" by the power of the chevvy then it would have happened before now. It
would also be well documented on the cobra club site, but I've seen nothing.
HTH
Vince Gledhill
Time Served Auto Electrician
Lucas Leeds 1979-1983
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dashin_dave
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| posted on 2/10/02 at 05:18 PM |
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i dont doubt the sierra capability to cope with a 300hp natrually aspirated 350, its the 500+hp blown one i'm skeptical of.... in fullsize cars,
thats prepped 9' only territory
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johnston
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| posted on 2/10/02 at 06:59 PM |
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with 500bhp+ i dont think anyone will need to worry bout the diff after all in somethin the weight of the locost it will a) sit and spin b)probably
twist like a corkscrew it (is only 16 guage tubin after all)
and....c) be in a hedge long b4 difff gives any wiff of trouble
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johnston
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| posted on 2/10/02 at 07:05 PM |
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oh!!!! and why go yank i have an old mag somewhere guys in aussie land usin a jap spec lexus engine in a mx5 look a like built in the same vain as a
strathcarron or sumit
cant remember if its a v6 or 8 but can take 500bhp with no internal mods is rwd so donor comes with everythin and all the runnin gear can take the
power and would be lighter than a yank tank and must be small if it fits into sumthin the size of a mx5
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VinceGledhill
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| posted on 2/10/02 at 11:44 PM |
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Sit and spin sounds about right. I undertand the need for speed but surely this is so over the top that it will render the car completely
un-drive-able.
Please correct me If I'm wrong. I hope I am cos If that is the case I'm going to build one.
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bob
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| posted on 3/10/02 at 06:45 AM |
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Its well known that some sierra cosworth owners manage to squeeze 500+HP out,the diff seems to cope with it ok.
The part i've heard fails is the beam axle that holds the diff 
Talk to hicost on here,he's running best part of 400 brake into an LSD 3 litre senator diff in a locost chassis.
I'm sure i'll be corrected if wrong on diff.
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dashin_dave
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| posted on 3/10/02 at 06:25 PM |
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hmm... collective reply post here... sit and spin, yea, probably, but to some extent that can be cut down by big fat tyres, say 12" m/ts would do
okey. twist like a corkscrew, hehe.. also probable, but then again, what are top fuel dragsters made out of? into the hedge, almost gaurenteed, unless
its treated very cautously. as for the weight, i'd guess it'll end up around the 900kg mark, but thats just a guess, so its not really locost weight
anymore.
lexus donks. absolutely beautiful pieces of engineering, alloy 4.0L 24v V8, 190KW, or 255bhp out of the factory. supercharging them is the usual
option, use factory internals and a lil underbonnet blower and you'll get about 350-400bhp. you can get them in halfcut form in australia for about
A$2000 or £700, (you want a toyota soarer one) not sure what you'd get one here for, but one thing of note is that you can only get them mated to an
automatic transmission, and in changing them to a manual, you also have to replace the computer with an aftermarket management system, which is at
least another A$1000-1200 or £400.
as for wether it will be drivable.. wait until someone is silly enough to finish one and then we'll all know?
with regards to the cosworth owners though, there is an explanation, a little cosworth donk might make big bhp figures BUT i'm pretty sure you'll
find the torque figures are lacking quite a bit when compared to the big cube blown engine. i dont really know cosworth engines, but as far as i knew
its not really possible to get really big torque figures out of a 2 or so litre engine. a big yank v8 however, as a rule of thumb, produces something
around 1bhp:1ft-lb of torque, so 500bhp=500+ ft-lbs of torque. in my experience, its torque that breaks diffs and gearboxes, not horsepower. take a
rotary for example, you can jam a 300bhp rotary in an rx-3 with a standard diff and hammer it all day, put in a 250bhp v8 and you'll have chunks of
mazda diff all over the road in about 2 minutes. *shrugs*
just me waffling on again, all of this is my opinion, so some of it probably doesnt have a heap of basis in fact.
regards
dave
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rallyslag
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| posted on 4/10/02 at 08:07 AM |
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ill probably just go with whatever diff i get my hands on at the time and see how it lasts
if it explodes then ill just have to get a bigger one
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john_s
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| posted on 4/10/02 at 05:40 PM |
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quote:
ill probably just go with whatever diff i get my hands on at the time and see how it lasts
if it explodes then ill just have to get a bigger one
That's how i'd do it.
John.
--
John Singleton
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