maximum engine / stroker size available?

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Kevin Whitehead
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maximum engine / stroker size available?

#1 Post by Kevin Whitehead »

I have a T5 project about to start (gotta sell by T6 first...) I am looking to make a big torque monster engine...Well within the car / gearbox / engine limits anyway.
The catch is to maintain the stock look. I will be going for the 12V alternator mod based on the later generators to keep the look.

I have seen the Willholit data on the engines (twin plugs etc and stoker up to 2002cc in size) I am looking for feedback on others who have gone down this treacherous and expensive path to torque.
As an absolute minimum I will go to a 1720 big bore and that will see the limits of the Zeniths possibly over them. Any feedback on how I can increase the flow out of these? CJ indicated these are close to maximum at around 100hp?

I am looking at a new counterweighted crank (probably SCAT), conrods, pistons and cylinders and head and intake mods as well as the usual 200mm and lightened flywheel. I will look at a full flow filter if I can get to it to be hidden as much as possible (i.e remote)

I have sent a few emails to suppliers to look at the knowledge and parts available. I want to do the majority of work myself and use packaged kits and only farm out specialized machining where necessary (i.e. case machining and lineboring / verification etc). There are not a lot of 356 specialists in Western Australia.....
T5 engine.jpg
Any suggestions on engine combinations woulds be very much appreciated. Direct responses to kgwhitehead@dodo.com.au if you don't want to placed this on the forum.
The collective value of this forum is brilliant and my previous T6 project would never have been finished without it.

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C J Murray
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Re: maximum engine / stroker size available?

#2 Post by C J Murray »

The maximum sizes as of now are 91 mm bore and 82 mm stroke and that equals 2133cc. Until I initiated the use of 45 mm connecting rod bearings the largest stroke was 77 mm gained by using a Chevy 2" connecting rod bearing which was how Willhoit achieved 2002cc before I made John aware that I was using 45 mm bearings and he followed suite.

My personal 2133 has just turned over 20,000 miles and has traveled coast to coast as well as being my daily driver. There are a number of potential pitfalls when building one of these large engines and I actually have my engine on its third development version. These engines are very tricky to make smooth in terms of vibration and function but they are very robust and reliable. I wont share all the details of what I have learned but the difference between the first version and the last is startling. I have not measured the latest version but the first version made over 160hp on the engine dyno.

I have measured rear wheel power on a 1720 S90 at 91hp and that is a very well mannered car. That would be 105hp or so at the crank.

There are various displacements depending on what bore and stroke combination you choose. Right now I am building a 1905cc stroker.

Zeniths will work on a large engine but keep the cam very mild.

Twin-plugs is a religion, not a horsepower improver. Obvious negatives are expense and complicated and unreliable electrics as well as weaker cylinder heads more prone to cracking.

Madd Scientist combustion chambers are a waste of effort. Work on the basics of improving the 30* design. Even the 22* will work well with a quality 22* piston and some minor attention to the details.

Basically, you need to spend your money on effective mods and avoid hype mods.
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Jacques Lefriant
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Re: maximum engine / stroker size available?

#3 Post by Jacques Lefriant »

Hi Kevin
don't take this the wrong way. Building and sorting out a custom engine is not for the uninitiated. Although there is a whole industry of vendors and builders for the VW aircooled engines the parts for the 356/912 engine are very pricey and have not been offered as complete package other than Willhoit. If you want it to look stock why not keep it stock? you can get a whole lot bang for the buck with other engine like the type IV.
j
 

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Ronald Sieber
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Re: maximum engine / stroker size available?

#4 Post by Ronald Sieber »

I have ridden in CJ's torque monster and It was a real treat. Idles nicely, powers easily from low revs, very tractable and responsive. I bet he would build you one... Not sure how much it would cost compared to Wilhoit, if that is a concern. As Jacques pointed out, a VW Type IV beats all in the price department...

Jus'Sayin'
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Kevin Whitehead
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Re: maximum engine / stroker size available?

#5 Post by Kevin Whitehead »

I will not be doing this unassisted, I have the resources of 4 or 5 people who have already offered to help me build this and who fall into the category of highly skilled in engine building and 2 off are VW and 356'ers. They will help me build it and have the contacts to get the machining done as well. They guys want me to chase down the parts and gear and they will direct me whilst having a few beers supplied by me. I reckon I get a good deal out of it. Great company and skilled knowledge.
I am having discussions with a few guys in the USA about parts, hopefully they can help.of at least continue to provide good counsel. Building remotely by others may be great but I want to do this myself (mechanical engineer by profession).
Thanks for the help. appreciated as always.
Kevin

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Jacques Lefriant
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Re: maximum engine / stroker size available?

#6 Post by Jacques Lefriant »

Hi Kevin
good on you mate i applaud your commitment. email me if you have specific questions.
j
 

Conrad Carter
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Re: maximum engine / stroker size available?

#7 Post by Conrad Carter »

Subscribed. I have a hot Type IV engine. Dreaming about a hot 356 engine!
Conrad

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Greg Bryan
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Re: maximum engine / stroker size available?

#8 Post by Greg Bryan »

Some pictures of Wilhoit's 2133 engine I took at the Lit Meet open house ...
IMG_0162.JPG
IMG_0153.JPG
WR6.JPG
WR22.JPG
WR33.JPG
WR4.JPG
WR11.JPG
WR5.JPG
Note the oil squirter on the front cylinder opening
Greg Bryan

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