603S Engine

[will7262]

Well in a fit of madness I bought a rather tired looking 1982 603S on Ebay last week.

She comes with no history whatsoever but has a fresh MOT.

OK she will need a complete repray, new headling, veneer work....I could gon on.

First thing is to get the engine, brakes etc tip top then move on to the cosmetics.

The question is how do I uprate the engine to say 300HP and will the gearbox propshaft, differential take it?

No doubt there are many of you who have done this before so all advice on whats best and where to get parts etc will be very much appreciated.

Thanks in advance

Will

[GREG]

You could probably go to 450 HP without causing any traumas but doubt you will need it !

I have a good local bloke for the woodwork and could probably do a swap, as I have a spare dash. -- and headlining etc.

Newer alloy wheels will help the look.

Let me know what other bits you need and get advise from ACCS on the engine upgrades. 0207 713 5470

Have fun , it's a great car to drive.

Join one or both of the Bristol Owners Clubs

[will7262]

Greg

I will send some photos of the headling and dash etc. perhaps we can then chat about your proposed swap. I must try to figure out how to upload photos to this forum but for the moment please send an email to
will.ch@btinternet.com so I can send some to you.
Cheers
Will

[Janne]

I would replace the propshaft and UJ joints if I upgraded the engine.

[Janne]

An idea: Could the two threads about this car be merged?

Please keep us updated about your findings and progress!

[Janne]

OP! Do you plan to restore the engine yourself?

[will7262]

Janne
I will of rebuild the engine , suspension brakes in fact anythg mechanical or electrical myself...with the help of Andrew my brother.

I have the luxury of a large double garage /workshop in London and Andrew has far bigger facilities with car hoists etc. in Exeter.

In fact he only thing we will not tackle in this instance is the paintwork and I suspect once we understand the extent of the aluminium corrosion issue some of the bodywork.

We will once all mechanical/brakes/electrical/new headling etc. work is done look at the body work issues. I expect we will strip everything off her including all glass etc. and remove paint in corroded areas back to metal and go from there.

I wonder if wheel arch repair panels are available? Antbody out there know?

The unknown future of the Britol parts supply is a bit of a worry as I called them the other day and they had no facility to take payments for parts which rather limits whta can be done.

They also didnt have a front and rear screen rubber which is a bit of a worry given what I intend to do. Will have to be very carefull when removing the existing ones but experience tells me the rubber will have gone hard and will have to be cut to get the glass out.

Will

[GREG]

ACCS has the rubbers

[browning l]

Will, would it be imposing on you if, on my next visit to the UK - Scotland and London, probably in late November, early December, to see your car in its transformation?

[will7262]

Can anybody enlighten me as to what ACCS stands for the and contact details?
Yes I am new to this so ecuse my lack of detailed knowledge.

[GREG]

Originally Posted by GREG

You could probably go to 450 HP without causing any traumas but doubt you will need it !

I have a good local bloke for the woodwork and could probably do a swap, as I have a spare dash. -- and headlining etc.

Newer alloy wheels will help the look.

Let me know what other bits you need and get advise from ACCS on the engine upgrades. 0207 713 5470

Have fun , it's a great car to drive.

Join one or both of the Bristol Owners Clubs

American Car Care Centre

[Kevin H]

Originally Posted by will7262

The question is how do I uprate the engine to say 300HP and will the gearbox propshaft, differential take it?

Assuming the gearbox propshaft and differential are the same as those that went before it (411/412) and those that after, Beaufighter, Brigand etc, then there will be no problem coping with 300HP.

As for how to get 300HP, it's an eminently tunable engine, with heaps of information and after market parts available. But what does the engine put out now? have you had it on a dyno?

[will7262]

Kevin

I have no reason to think she has been modified so assume all the running gear is standard.

My researches seem to indicate that with a 4BBL carter carb and an 8.4 compression she will have something like 225 HP. This may well be an American SAE figure so probably more like 200HP DIN. Not a lot for a car of this sort of weight.

[Kevin H]

Will,
I guess it goes without saying that an increase of 200HP to 300HP isn't going to be achieved with a couple of bolt on goodies, other than perhaps a turbocharger!

The good news is that the engine can produce a hell of a lot more power than 300HP, so it's just a matter of how you achieve it. Where do you stop? What gives the biggest "bang for buck"?

To my mind you want more torque and power within the same rev range, then you don't have to worry about the crankshaft and things like roller cams. What you consider doing to the engine depends on what condition it is in. The bottom end doesn't need much doing to it at all as the stock crankshafts were very strong to begin with.

Improved breathing is a must. A decent increase in power and torque could be achieved with some mild porting of the heads, bigger valves, a better intake manifold, and a modern carby with tuned jetting. Ideally you should also install some different pistons to increase the CR and a higher performance cam shaft to take full advantage of better breathing.

I'd also go for an electric fuel pump with pressure regulator, it could also be worth replacing the original water pump with an electric one.

There are a few books on the specific topic of tuning Chrysler "A" Series Smallblock engines.

OR you could just buy one of these Crate Engine - Chrysler 360 Engine

[Kevin H]

Just to clarify, what I mean when I say "The bottom end doesn't need much doing to it at all ", is that other than making sure the all the bottom end bearings and crank bearing surfaces are in good condition, it doesn't need any modification to cope with 300HP in the normal rev range.

[Kevin H]

Sorry, one more thing!

When I say "A" Series engine, it's technically the "LA" Series, but they are often referred to as the "A" Series, which can cause some confusion, because the old 313/318 used in the Bristol 407-410 were in fact the original "A" Series, but most Mopar enthusiasts seem to have forgotten about them!

[will7262]

I have to say the crate motor approach looks very attarctive but shipping costs from the states to UK and then import duty and no doubt VAT might tip the balance to rebuilding the original lump.

I wonder if anyone has fitted some sort of header or a better cast exhaust manifold to a 603 and later car. All about clearing the chassis I guess.

[Kevin H]

Originally Posted by will7262

I wonder if anyone has fitted some sort of header or a better cast exhaust manifold to a 603 and later car. All about clearing the chassis I guess.

According to the experts, Chrysler's original cast iron manifolds were quite efficient and able to handle "street" performance upgrades. 300HP certainly fits into this category.

The cost of getting custom headers made would probably not be warranted in terms of performance increase and may create problems by increasing the engine bay temps.

I am assuming that Bristol used the stock Chrysler exhaust manifolds, as they did on the 411.

[Janne]

If you ship the crate engine by ship, it is not so expensive.
I contemplated to do the same, but as I value originality, I had the engine restored (and upgraded) in UK.
NOT bu the American Car Centre (I think the name is) but by a local guy who happens to be a V8 specialist.

ACC quoted me 12K UKP, I think he did it for under half of that.

[GREG]

Small Block Mopar 360 Crate Motor--Edelbrock heads on eBay (end time 15-Apr-11 18:05:18 BST)