Bottom end rebuild advice for 380bhp

[20vcqdriver]

I am hoping to start gradually building up a new 3B bottom end for my Cq over the next 12 months (as and when funds available) and intend to build it to withstand the proposed 380bhp and subsequent torque. Having spent a lot of time searching for whats best and not getting a 100% answer I thought it would be easier to just ask what are the best components to use for this. I.E. type, spec and company to buy from etc for rods, bearings and pistons.
Looking to rebore block and use appropriate oversize pistons if these are available and hope to be still able to use the standard metal ADU headgasket with it. Thanks.

Once this is sorted I'll be after all the turbo options with the aim to retain the normal 20Vt characteristics of quick spool up and response to throttle without the need to get have the revs over 3000rpm. So guess I am looking at a ball bearing turbo with RS2 flow rates. Intend to use RS2 injectors and fuel pressure regulator too.

[msh]

So, what's the reason to build something - u have worn out 3B? 20vt engines with original pistons etc can withstand up to 450 bhp and ABY engine can be upgraded to some 350 bhp with "RS2 kit"
P.S. Is oil seperator included in your parts list or pressure in crankcase wouldn't be sufficient to suck all oil out?

[20vcqdriver]

Originally Posted by msh

So, what's the reason to build something - u have worn out 3B? 20vt engines with original pistons etc can withstand up to 450 bhp and ABY engine can be upgraded to some 350 bhp with "RS2 kit"
P.S. Is oil seperator included in your parts list or pressure in crankcase wouldn't be sufficient to suck all oil out?

BOTH! As I intend to refurb the 3B block whilst parts are available (and will be the last time it will need doing in my lifetime as I am limited to 3000miles on the insurance) I might as well make it bomb proof for the power I will be using. Some on the S2 forum have bent rods after reaching 380bhp with the RS2 turbo due to massive torque, so best to play safe and will at least know I'll have no further worries if I at a later date decide 380bhp is not enough

[msh]

You're talking about certain amount of power and not torque Don't remember how much was 20vt upper torque limit, something about 500 nms maybe and it can be reduced. Part aviability - last 20vt came off production line only 12 years ago, aftermarket pistons, rods, main bearings will be aviable as long as humans will use internal combustion engines and the same seals, I think, was used in newer engines as well. So I don't think engine part aviability would be problem for at last 10 years.

P.S. Can u explain to me, what's that mileage limit?

[20vcqdriver]

Its the torque that bends the rods and yes it can be dialled down but its the torque that gives you the big push in the back so why dial it down, so after other people have fallen foul of running standard engines and bending rods after passing 360bhp+, its not worth the chance for the sake of a few hundred pounds now compared to the cost of bending a rod at 5000rpm+. My engine wear is not near the limit but do not want to be retiring and still not have this refurb finished and able to enjoy it...
So far it looks like Scat rods and possibly just a re-hone with new rings and an uprated version of the ABY/RS2 bearing shells. Just need further info on brands and where best to get them....

[newt]

ok im running 300 hp in my s2 with all standard internal components
im now looking at going 400hp so my research has told me that you dont need to do a lot as the standard engine is very strong.
all you need for up to 450 hp is uprated rods and rs2 spec bearings/ gaskets.
i have started accumulating the parts
scat /tsr rods(h section)
rs2 engine bearings
rs2 gaskets
rs2 manifold
kkk26/27 turbo(not yet purchased) this will see450 happily in the correct ar. and fits like standard one
044 fuel pump
injectors?? not yet....
its really simple, you dont even need to change the pistons unless you HAVE to rebore
so im using h section rods, a balanced crank,
a "good" rebuilt head with maybe a bit of port/polishiing with a pair of 7a cams of other aftermarket cams will also do
there is only one problem that i have come across with the 3b setup and thats the "spaark hop" which can cause a problem , soome people have the problem at350hp some are running 450 without the problem
obvously you need the apropriate turbo and injectors

[20vcqdriver]

Thanks,
So just some new ABY/RS2 bearings will do.
Not changing cams as turbos do not like overlap and although it would increase top end power you loose torque and increase lag. Best compromise would be to just change the ex cam as that is all Porshe did with the RS2 engine.
RS2 ex manifold is something I had not considered, is it that much better?
Where is the best place to get rods that come as a matched, balanced set?
Already have a high capacity KV pump that will hopefully be enough, Will have to wait and see.
Just been looking at this turbo from 034 motorsport. Probably suit me if it fits RS2 manifold.. http://www.034motorsport.com/product...roducts_id=321

Originally Posted by newt

ok im running 300 hp in my s2 with all standard internal components
im now looking at going 400hp so my research has told me that you dont need to do a lot as the standard engine is very strong.
all you need for up to 450 hp is uprated rods and rs2 spec bearings/ gaskets.
i have started accumulating the parts
scat /tsr rods(h section)
rs2 engine bearings
rs2 gaskets
rs2 manifold
kkk26/27 turbo(not yet purchased) this will see450 happily in the correct ar. and fits like standard one
044 fuel pump
injectors?? not yet....
its really simple, you dont even need to change the pistons unless you HAVE to rebore
so im using h section rods, a balanced crank,
a "good" rebuilt head with maybe a bit of port/polishiing with a pair of 7a cams of other aftermarket cams will also do
there is only one problem that i have come across with the 3b setup and thats the "spaark hop" which can cause a problem , soome people have the problem at350hp some are running 450 without the problem
obvously you need the apropriate turbo and injectors

[BW2309]

You'll definately want a Bosch motorsport fuel pump with the RS2 injectors. The pump is either the 044 or 040, one is in tank, other external. Pistons will cope fine with new standard ADU rings. Rods not a must but while it in bits is best time to swap and they will reduce moving mass. A lightened flywheel will help low speed response too. U have 3b at min? The ABY and ADU had duel mass flywheel and a spacer on front of 'box. RS2 ex manifold and cam a big help. U need 3B inlet cam to run your Distributor.
Get the head polished n porter and manifolds matched to the head. This will help reduce that horrible lag and help torque! Don't go mad with intercooler size too as again causes lag due to volume. A mid sized cooler with a powerful fan to help it at low road speeds will help.

[20vcqdriver]

The series 2 never had a fuel pump in the tank, just a meaty one under the car. This I have changed already for a high capacity version. Will wait to see if it is capable or not of supplying enough fuel...
Once I have this spare block in a few weeks I will know whether I can get away with just a rehone and new rings or whether I need the 1st oversize pistons.
The 3B is one of the lighter 5cylinder flwheels so happy to stick with this and mates perfectly with my 6 speed box.
Will stick with standard cams for now and after reading some peoples reports on fitting the 7A inlet cam would only ever change the exhaust cam at a later date.
Presently using a chargecooler capable of handling 600bhp so no worries there.
Can you recommend any companies to get things like pistons (if req) rings and rods from other than 034 EFi who seem a tad expensive.....

Originally Posted by BW2309

You'll definately want a Bosch motorsport fuel pump with the RS2 injectors. The pump is either the 044 or 040, one is in tank, other external. Pistons will cope fine with new standard ADU rings. Rods not a must but while it in bits is best time to swap and they will reduce moving mass. A lightened flywheel will help low speed response too. U have 3b at min? The ABY and ADU had duel mass flywheel and a spacer on front of 'box. RS2 ex manifold and cam a big help. U need 3B inlet cam to run your Distributor.
Get the head polished n porter and manifolds matched to the head. This will help reduce that horrible lag and help torque! Don't go mad with intercooler size too as again causes lag due to volume. A mid sized cooler with a powerful fan to help it at low road speeds will help.

[ZermattGT]

Man. 380bhp? Isn't 300 enough in a Coupe Quattro? Once you base a HP for every 10 lbs. of weight you've pretty much hit the magic number for driving fun and ferocity. Are you turning the CQ into a track beast instead of a Sunday driver for the immortals?