16v internalls

[trickystorm]

hi there can any one advise on how i can get the 16v engine  to rev alot higher cheers john

[Wayne]

How high do you want it rev 

[trickystorm]

How high do you want it rev 

realistically  8.500/ 10.000 rpm  on a four speed box lol

[sharki786]

is there a reason why you want it to rev higher?
i remember when i was going to get my flywheel lightened & balanced and some guy said he needs the crankshaft to balance it properly and someone of here said the only reason to lighten the crankshaft is so you can rev alot more.
so you could try that, lightened flywheel & crankshaft and get the rev restriction removed but its there for a reason (stop you from shooting your pistons through the bonnet)
also the head will need work such as sport springs, air intake mods (drilled and smooth airbox, ported throttle body, ported & polished inlet)

[trickystorm]

well to be honest i want to do something different and it seems that running a 4 speed box and reving that high will destroy on sprint/ 1/4 mile thinking  so far twin 45s carbs  instead of injection

[Wayne]

Danny P or Glen (ess-three) is the one to ask but I think you looking at a lot of work to get it to rev that high.

[Len]

Actually EssThree is THE guy!
Not sure about 10k revs but 8500/9000 is more likely.
Will not be cheap either!
Throttle Bodies and Emerald ECU is £2.5k

Also a lot of threads about this subject on ClubGti

[AudiA8Quattro]

Yep Glen certainly appears to be the no.1 expert on the ABF lump.
Too much money to burn 

[DOA]

Im going to put my tuppeneth worth in imagining you want reliability here so....

Minimum of uprated forged pistons, rods and gudgeons, possibly different rings, possibly different big end and mains bearings, lots of head work, cams, solid lifters, uprated valve springs, possible cutouts to avoid the cams, altered compression ratio, mains straps??, lightened, balanced and knife edged crank with some process like tuftriding going on too, throttle bodies and standalone management, dry sump kit and other tweeks to the cooling system, a shedload of money and plently of forward planning on the rebuild schedule (it will be frequent at 9k, instant at 10 lol). Your looking well over 10k IMO to put together a motor that will rev that high unless you find someone else that has already developed a similar package. As for the 4 speed box, just find a diff ratio that suits a box that will cope with the sort of engine you are looking to build and only use a few of the gears, your looking at sod all weight loss and a probable lack of reliability using a 4 speed thats developed for low power engines over a 5 that at least was designed for something interesting. In fact, your going to have to look closely at the gearbox internals that you wselect to make sure they deal with the engine your looking to build so add up to 5k for that and a decent clutch as well. The one last thing you will need is some form of proof you built it if it ever gets to 10kRPM  .

BTW, if its for sprinting etc, driver tuition will be a far cheaper method of going faster than jumping in at the deep end with some revmonster engine under the bonnet.

[danny_p]

10k rpm is hard work

the way we went about it with the cordoba engine.

take a high miles bare block.   check the block is still true, then macene the bottom of the block off down to the centerline of the cranckshaft to enable the use of a crank ladder.

the remove as meany stress risers as possible both internaly and externaly, then you need to bore the block right out and have high tenstile steel liners pressed and bonded in. then bored for the fatest pistons you dare fit

the crackshaft need some love and attention as well,   the trigger wheel needs to leave in favor of external one as it won't do 10k rpm we built the big end journals up andso they chould be reground to reduce the stroke but maintain bearing area. 

the conrods you need for 10k rpm are also rather spectial and a lot of ££££  when you look at the G's the pistons get and work that back to the forces been applyed to the rods they get scary.       to make it worth it you need a really spectial cylinder head bog std ported head isn't good enough,  we had to get in there with the tig and add metal to aid the reshapeing of the ports as the waterways have a habbit of getting n the way

also at 10 k rpm inlet tract length, exhaut headers and cams all have a massive effect on how the engine behaves  and there is alot more to it than that.

and there is a hell of more to it than that, what you really need to find is a drake cylinderhead or and audi motorsport one.  bear in mind it wount be reliable if anythign at all whatsoever founs up in there when its revving in the powerband you won't notice till it's to late the engine wil just grenade into an oily splat, the cordoba engine fell in half when the head was unbolted after it went splat playing in the forest was going to have crack at the wyedean rally but we killed it before we got there

8.5 krpm is easy by comparison just forged rods high comp pistonds and arp bolts