Aussieveedubbers · General Chit Chat

big bore kit

https://forums.aussieveedubbers.com/threads/72054/big-bore-kit

baja burley ·

i pulled apart my "siezed" 1600tp yesturday and found a conrod sticking out the top of the crank case so i pulled everything apart down to the crank and found that 2 pistons are cracked, 2 cylinders are cracked and one conrod is samashed!! instead of replaing all this with stocko parts i concidered a big bore kit.. what exactly does a big bore kit contain?? and i was told that the biggest i could go without machinig is 1680cc is this right???

can someone give me a bit of info on the topic i.e how to fit, price, advantages disadvantages,

bond ·

try a search for 1641, 1776, 1835, 1914 1915 or 1916 in tech forum and am sure you'll find ample info and discussion on pros and cons of kits all the way to building a stroked motor...

the same kind of question is asked fortnightly and the replies are often similar.... has become repetitive...

nick

Camo ·

yesturday and found a conrod sticking out the top of the crank case


If you have a rod out the top of the case, I think you will be throwing most of your engine away.

LIFE IN THE LOW LANE ·

Bin it by the sounds of it.

Or better still have a bonfire then put the crankcase on the fire......

karmannghia60 ·

Big bore kits are basically pistons and cylinders with slight large diameter than stock but the outside diameter of the barrals are the same as stock hence it fits in the standard case without having to machine it. However you end up with a barral with a thinner wall which can case warping eventually and usually big bore kits have a short life than stock. As far as I know, the extra "power" you get is not worth having a much shorter engine life. If I recall correctly, the 1641 is 87mm diameter compared to the stock 1600 which has 85.5mm diameter
Raf

Bizarre ·

The 1680 is an 88 slip in - VERY thin
The 1641 is 87. You hear both sides with this one.

My 1916 has a 20% increase in capacity over a stock 1585 and gives about a 25% extra power.
The only real difference is capacity

A 1641 is 3.5% increase in capacity over a 1585 - so........................

If i had them - use them
Would i pay extra over 85.5's
Nah - Spend your money else where

baja burley ·

what sort of $$ would i be looking at for a 1641 kit?

Stanley ·

My turbo (which you saw at the boat ramp) is a 1641. By the carnage you decribed you might be better off ifinding a new engine. The coin will quickly add up once you start replacing bits. They come up here from time to time. I have some bits if you want to rebuild whay you have.

RISKYBUG ·

about 250 bux for 87mm pistons rings etc

vwtyp2 ·

can help you out with a set of 92's in great 2nd hand cond. I bought a new set of 94's and don't need them.

this will take you out to an 1835cc but will require some machining.

sounds like your case is shagged anyway, if you're gonna make an improvement, you might as well make it worthwile.

baja burley ·

thanks guys. the case IS shagged so i put that in the long term to do pile and might weld it up one one day... i got a single port of a fella and he rekkons its got a mild cam in it so im just gonna put my heads on that and see how we go from there - should be able to make one good one out of two shagged ones!!

vwtyp2, where can i get the machining done and what are you asking for the set (pistons and barels?)

RISKYBUG ·

have fun welding it 🙂 if it's not an as41 case !!!

vwtyp2 ·

whoever you get to rebuild your engine shouls have machine shop contacts, or ask at your friendly local VW parts supplier.
$250 for the set, which includes pistons, barrels, rings, and wrist pins.

marcaant ·

yep absolutely, if you look around you will find a kit cheap....i bought one from the states few years back

marcaant ·

One more thing,

If you can spend the extra $$$ at the workshop and get everything mchined properly. I once didnt bother and ended up with a poor running engine that scored the bored and needed a second rebuild.

VWCOOL ·

marcaant wrote:One more thing,

If you can spend the extra $$$ at the workshop and get everything mchined properly. I once didnt bother and ended up with a poor running engine that scored the bored and needed a second rebuild.
Er... you don't NOT spend the money on proper machining

baja burley ·

will do... any places you recommend getting it done??

Craig Torrens ·

baja burley wrote:will do... any places you recommend getting it done??
yeah Australia's best......Stan Pobjoy 02 66543694.

baja burley ·

in brisbane maybe??

VWCOOL ·

Call a courier... will cost $75 or so for shipping

JVLRacing ·

Craig Torrens wrote:Australia post will ship a case for about $25 to Pobjoy.................cheaper than getting someone local to stuff it up !
that should stirrrrrrr the natives up😂

bugmatic ·

I'd be looking carefully at a pre-built 1916 long motor. Save yourself the hassle of organising machining and sourcing parts. Provided you don't drive like the devil himself, you should get plenty of miles.

baja burley ·

probly dont have the cash for a brand new 1916 at the moment!

how many moneys does pobjoy do this kinda machining for??

amazeer ·

you can probably keep the coil 😏

baja burley ·

can anyone quote me on this machining - including postage. if i already have the new bore kit

cheers

matberry ·

I can get it done for budget option for $100 or flash job for $220

amazeer ·

you should seriously budget for a new or 2nd hand crank as well. If its done any smashing of pistons heads and rods then it is going to be shagged as well.

baja burley ·

the only thing i kept off the smashed engine was the heads (dual port) to put on the new single port Motor

Matberry, is that for the crankcase as well as the heads or just the case??? also will you need to see the barrels for dimensions??

cheers
luke

baja burley ·

does anyone know what sort of power id be getting out of an 1835 with say a pair of 36idf's and extractors???

matberry ·

Mate, no barrels needed, that price for case only.

baja burley ·

will my twin port heads still do the job on an 1835. and will i get i get away with stock carburetor set up till i get time to upgrade??

Joel ·

92mm pistons arent the best choice

1835 are shit for a reason
they are just 1776 with thinner walls for more capacity
so they the warp and leak compression and run hot
ask anyone who actually knows about engines thats had one
their ok in something light like a buggy that itsnt working real hard but not the best choice for beetle/kombi/type3

if ur starting from scratch just go 94mm u will thank urself when ur engine still has perfect compression after 30,000kms