Engine enhancements

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Simon Whittley
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Engine enhancements

#1 Post by Simon Whittley »

I'm looking to get a little more poke from my '59 1600 356a and considering the AA Performance 1720cc 86mm Piston & Cylinder kit. My engine currently completely standard apart from 123 Electronic Ignition (6 volt). I have standard Zenith 32 NDIX carbs.
Is there anything else I should / would need to fit in addition to the cylinder kit?
I'm also considering the Stoddard NLA-111-010-05-SS Stainless Steel sports exhaust too. Any thoughts on this?
Simon

Chuck Allard
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Re: Engine enhancements

#2 Post by Chuck Allard »

Cubes and compression for a bit more power. The 1720 cc kit has a few more cc's and the A/B kit is about 9.2 to 1 compression vs your stock ratio 7.5 to 1. Stick with the stock muffler and carbs.

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David Jones
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Re: Engine enhancements

#3 Post by David Jones »

Do not install the 1720cc big bore kit without changing the connecting rods. There is a better than evens chance that you will break a rod if they are still original to that engine. At minimum replace them with the later "B" rods but preferably the "C" rods.
Make sure to buy the kit with the 22 degree pistons not the 30 degree ones unless you also upgrade to later heads, If you upgrade to later heads then you might want to upgrade to super Zenith carbs. It is a slippery slope you are getting onto when you start improving, one thing leads to another and then you will be like me with 100 hp in a 59 coupe and the original 60 hp engine setting under the bench.
If I had known I would live this long I would have pushed the envelope a little harder.
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C J Murray
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Re: Engine enhancements

#4 Post by C J Murray »

Are you doing a complete rebuild? What size venturis do you have now?

My current favorite combination for Zenith cars is basically stock C spec which means 28mm venturis with C jetting and a C cam. The CR doesn't have to be exact but very low 9s is about the max. The squish angle can be 22* if that is what your heads are. The pistons must match that angle. This results in a very strong performer up to 5000rpm. To get more power you need to use higher rpm and that would be better done with a large oil pump engine.

If your engine is a little tired you will pick up quite a bit of power from better ring seal and valve seal just from the rebuild.
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John Ward
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Re: Engine enhancements

#5 Post by John Ward »

AA is out of the 22 degree big bore piston and cylinder set.
So is Zims
They have the C- 912 P&C. you could get them machined
 

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Eric Wills
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Re: Engine enhancements

#6 Post by Eric Wills »

Shasta Design has an 83mm 22 degree set that would work very well for your application. AA stuff is somewhat decent, but you have to inspect everything very carefully.....

EW
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Ron LaDow
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Re: Engine enhancements

#7 Post by Ron LaDow »

The Pre Mat parts won't fit a '59 case, but I'd suggest you put some serious efforts into getting decent filtration fitted.
Any competent machine shop can fit an outlet to your pump cover and provide a threaded return to the timing case.
Ron LaDow
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Simon Whittley
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Re: Engine enhancements

#8 Post by Simon Whittley »

Thank you for all the advice and helpful comments. Although I have to confess I'm slightly put off that idea now. My engine runs absolutely perfectly at the moment and I wouldn't want to start risking throwing a con-rod just because I wanted a little more poke out of it. Engine rebuild isn't in the plan at the moment, as there is no need to right now.
What about brake modifications? I may have an option to buy a set of B brake drums, is fitting these a sensible idea? What needs changing? stub axles, brake back plates?
Simon

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David Jones
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Re: Engine enhancements

#9 Post by David Jones »

Simon, the only real difference in "B" brakes is the design of the drums for better cooling. Same brake cylinders and same brake shoes. If you only do hill climbs they will not help. I doubt there will be any benefit. If you plan on taking summer vacations way south of the English channel you may find a benefit then but Edinburgh is not going to get hot enough to warrant the slight edge on brake cooling you will gain. Buy a set of Koni shocks and improve the handling along with a set of good all season tires. I would suggest a set of summer tires but again to get the benefit of them I think global warming will have to accelerate to encompass Scotland.
If I had known I would live this long I would have pushed the envelope a little harder.
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David Pettengell
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Re: Engine enhancements

#10 Post by David Pettengell »

Hey Simon, I have a larger displacement engine built by Cliff Murray and I am about to order the new stoddard sports exhaust. if you are still thinking of one we could maybe save on shipping?

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Simon Whittley
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Re: Engine enhancements

#11 Post by Simon Whittley »

David Jones wrote:Simon, the only real difference in "B" brakes is the design of the drums for better cooling. Same brake cylinders and same brake shoes. If you only do hill climbs they will not help. I doubt there will be any benefit. If you plan on taking summer vacations way south of the English channel you may find a benefit then but Edinburgh is not going to get hot enough to warrant the slight edge on brake cooling you will gain. Buy a set of Koni shocks and improve the handling along with a set of good all season tires. I would suggest a set of summer tires but again to get the benefit of them I think global warming will have to accelerate to encompass Scotland.
Thank you David. Your memories of Scottish weather are spot on... Thank you for the advice. Regarding tyres (or tires!) what do you recommend? What are your thoughts on Avon cr6ZZ?
I already fitted Koni classics earlier this year. They have improved handling significantly. Are there any other handling mods you would recommend? Uprated anti roll bar or such like?
Simon

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Re: Engine enhancements

#12 Post by David Jones »

Simon, my experience and memories of driving in the UK were that tires made for Europe are a different compound to over here so I am not really qualified to speak for tires though past experience with Avon tires as fitted to my sons Scirocco years ago was very positive. If I could I would buy a set of Avons in a flash but I am afraid the CR6ZZ are prohibitively expensive over here at $300 each. I pay around $60 each for tires and they are much better than were on the car when it left the factory and I usually replace them on age not wear.
I think Vic Skirmants camber regulator would be the best upgrade you could spend your money on.
http://356enterprises.com/suspension-an ... rsche-356/
If I had known I would live this long I would have pushed the envelope a little harder.
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Mervyn Hyde
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Re: Engine enhancements

#13 Post by Mervyn Hyde »

Simon Whittley wrote:Thank you for all the advice and helpful comments. Although I have to confess I'm slightly put off that idea now. My engine runs absolutely perfectly at the moment and I wouldn't want to start risking throwing a con-rod just because I wanted a little more poke out of it. Engine rebuild isn't in the plan at the moment, as there is no need to right now.
What about brake modifications? I may have an option to buy a set of B brake drums, is fitting these a sensible idea? What needs changing? stub axles, brake back plates?
A sensible decision I suspect Simon. It is a long and at times slippery slope. A stock motor if set up well, in what is a light car, is 'what it is'. If one needs to go faster, drive a 911 or a Boxster IMHO. Perhaps spend your time on suspension and brakes linings.
Merv
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Doug McDonnell
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Re: Engine enhancements

#14 Post by Doug McDonnell »

If your engine is original then you might want to consider getting a C/SC/912 motor and building for fast street use. And save your numbers matching engine. I had a 1720CC 912 engine in my Outlaw and it was fun!
1965 356C 2000 BMW 740i Sport 1967 Honda CL77 There is never enough time to do it right, but always enough time to do it over.

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Simon Whittley
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Re: Engine enhancements

#15 Post by Simon Whittley »

Mervyn Hyde wrote:
Simon Whittley wrote:Thank you for all the advice and helpful comments. Although I have to confess I'm slightly put off that idea now. My engine runs absolutely perfectly at the moment and I wouldn't want to start risking throwing a con-rod just because I wanted a little more poke out of it. Engine rebuild isn't in the plan at the moment, as there is no need to right now.
What about brake modifications? I may have an option to buy a set of B brake drums, is fitting these a sensible idea? What needs changing? stub axles, brake back plates?
A sensible decision I suspect Simon. It is a long and at times slippery slope. A stock motor if set up well, in what is a light car, is 'what it is'. If one needs to go faster, drive a 911 or a Boxster IMHO. Perhaps spend your time on suspension and brakes linings.
I do drive a 911 on the road (and track) also so that satisfies my need to go faster, however more interested in entering my 356 in historical events and being able to complete a bit more against the faster historic machines.
Simon

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