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using Porsche barrels & cylinders?
sander288 - May 2nd, 2016 at 05:17 PM

Hi All,

I have found ALOT of information about using 80mm bore pre-A 356 Porsche barrels on the 36hp engines.

BUT, for the life of me I can't find anything about using Porsche barrels on a 1300 (F-series) case, probably due to the easier/cheaper bigger bores!

So I wanted to know if any of you knew anything about this? At the moment I have the F-series 1300 engine (69x77) I was looking at boring it out with new barrels to 80mm and possibly cracking the case to de-stroke to 64mm at the crank.

What are the specifications of 1300 vs 1200 (40hp or 36hp) barrels?

There is an option of custom LN Engineering barrels + JE Pistons but this is quite pricey, but may be the only option.

Any help apprecaited.

Cheers
Shaun


vw54 - May 2nd, 2016 at 08:18 PM

get yr 1300 case and bore to 1600 no problems buy VW don't buy Porsche


psimitar - May 2nd, 2016 at 08:43 PM

Those Porsche barrels are for people who really want to max out the 36HP using old skool speed ideas.

For a 1300 I don't see the point esp if you downsize the crank. Doing this will reduce torque even if you can up BHP.

If you want a 36HP to go well then best off just fitting a Speedwell charger. Makes the 36er much more driveable :)


sander288 - May 3rd, 2016 at 08:36 AM

I know that the VW barrels just slip into the case etc... but I'm looking at changing the bore to keep within class specifications for classic tarmac rally where only a 10% increase in capacity is allowed.

I think the best route forward is just get some 1500 barrels (83mm) and work from there with the crank (66x83) gives ~10% increase over stock.... or change class and do whatever but then less handicap points get applied!


modnrod - May 3rd, 2016 at 11:48 AM

I found some good 1500 barrels for my 76 x 83 motor I was building. The pistons I used come from an Isuzu G161 (Gemini), which I then had the piston pin holes modded for retaining circlips and then had the piston pins shortened to fit between them all, so they now fit stock VW rods.
I did this coz now I have quality hyper pistons for the 83mm barrels, and they have a compression height of 37mm (-2.7mm, although I had another 1mm skimmed off).
The whole deal all up cost me $320, and they weigh in at a smidge under 500g each pins, clips, rings and all.
http://www.precisionintl.com/Engine.aspx?ID=661&EID=1560 

Throw in your 64mm crank, add some rods the right length to join them all up close enough to make it work, then spin it up.


psimitar - May 3rd, 2016 at 04:31 PM

I'd go with ModnRods idea cos IIRC, from the HotVW Vintage Speed 36HP they did, then I don't think the barrel would fit the 1300 case. You'd have to have a ring spacer made to take up the slack plus have to machine the bottom 2-3 fins of the barrels so they loacted in the case properly.

I didn't buy the magazine but remember a fair bit of work went into getting the barrels to fit plus the pistons weren't VW or porsche but some aftermarket brand so with that in mind ModnRods idea really does sound the better option :)