Pushing the boudaries of the KO4

[Willie]

Gents,

I'm looking to start to blur the boundaries of the AMK KO4 to whats safe and whats fun.
Most of you will know my set up.
As of now I'm looking to do rods as I hope to get as much out of my LCR as possible.

I'm not looking to change the head and I'm not looking to change the intake manifold.

I am looking to change to the new 3" TIP's and I have a freer flowing exhaust manifold on its way.
I know I'm going to need rods but what rod spec do I need and why?

When do the pistons, lifters, springs and valves need changed?
I'm not looking to built a full on race spec engine, yet, as cost has to be considered.
I'm going to have my engine out so other things might need done as its out.
I'm not looking to balance my crank or flywheel just now.
I have a suitably rated clutch and flywheel for 360 ft-lbs so hope to not change that just now either.

I need informed please guys.

 

[csd_19]

Pistons are good for around 500bhp, so you shouldn't be near that on the K04

Lifters and springs tend to be changed when looking at a big turbo application which benefits from a higher rev limit to cover the high end powerband. Stock hydraulic lifters have been proven to over 9krpm by our 1.8T cousins over the pond at these revs obviously the springs and retainers need to be changed.

Valves - if you're going to be running the k04 hard then heat will be the main worry - the two-piece OEM exhaust valves can lose their head, although this can happen on any tweaked 1.8t tbh. Ferrera or Supertech upgrades for the exhaust valves is a common upgrade for peace of mind.

Any thoughts on running wmi to help with the heat?

What lum you got on there just now?

 

[Willie]

Pistons are good for around 500bhp, so you shouldn't be near that on the K04

Lifters and springs tend to be changed when looking at a big turbo application which benefits from a higher rev limit to cover the high end powerband. Stock hydraulic lifters have been proven to over 9krpm by our 1.8T cousins over the pond at these revs obviously the springs and retainers need to be changed.

Valves - if you're going to be running the k04 hard then heat will be the main worry - the two-piece OEM exhaust valves can lose their head, although this can happen on any tweaked 1.8t tbh. Ferrera or Supertech upgrades for the exhaust valves is a common upgrade for peace of mind.

Any thoughts on running wmi to help with the heat?

What lum you got on there just now?

WMI will have to be done to help control high EGT but not looking into this yet. There are heaps of options and heaps of knowledge on this now so will delve into that oner later.

My exhaust is Blueflame 3" DP, de CAT and 2 3/4" CAT back. I'm pretty sure I'm not going to need to change this.

So basically I'll need to change my rods and thats it?
Any suggestions for what spec of rods I'll need or what features to look out for?

Thank you Craig

 

[Indy]

THS 1.8T engine 20mm pins ones, you can either get them direct from them when there in stock or contact Alex Kerr

http://www.thsperformance.co.uk/product/VAG_1.8T_engine_20mm_pins_THSROD-18T20mm


Or you can contact Intergrated Engineering or Bob Quindazzi from http://www.qedpower.com/ where I got all the internals of my engine from.

 

[Willie]

Thank you Indy.
The THS ones were the ones I was looking at but they are not rifle drilled.
I've been advised that is is a good feature and I should try and get a set that's had this done

 

[Indy]

Thank you Indy.
The THS ones were the ones I was looking at but they are not rifle drilled.
I've been advised that is is a good feature and I should try and get a set that's had this done

SCAT Rods?

 

[csd_19]

How about the IE 144x20 rods? They can be rifle drilled for an extra £75 straight from IE.

Fair bit of difference of opinion out there around rifle drilling, some say yes, some say don't bother until big power, others say don't bother but put the extra money towards a really good set of rod bearings...

 

[RobDon]

IMO Willie, for track work which involves alot of bends, braking, acceleration - G-forces which will have your oil all over the place even with a baffled sump, I would say rifle drilled rods are a must to ensure constant lubrication and cooling of the wrist pins under track conditions. Get ACL rod bearings too while you're at it. Non rifle drilled rods and OE bearings are fine for fast road use but not the track.

As Craig said, exhaust valves can be a weak point, same with high temps in the K04 turbo which WMI helps reduce. ARP stud and nuts for the head are worth considering too, rather than OE stretch bolts. The OE hydraulic timing belt tensioner can also fail under hard use (or any kind of use!), so the manual tensioner kit is well worth considering too.

Why not speak to Issam at INA - I'm sure he would do you a good deal on everything you need?

This is all just IMHO of course, but I did research all of this when rebuilding my own engine.

 

[JNL]

I was pointed towards this thread by someone who was showing concern on their choices.

Basically Your wrist pin is supported by brass alloy bush this has oil distributed onto it by the 3rd oil scraper on your piston and your oil squirters for lubrication. When applying any sort of force this load is directly applied to the bush causing it to wear irrespective of the volume of lubrication. The bigger the diameter of the wristpin the more the load is spread out and the longer the bush lasts.

Alternatively you get the rods rifle drilled so now the wrist pin is no longer being supported by the bush but a pressurized oil layer like the rest of the bearings and moving components in your engine. Reducing the amount of wear and increasing the load the small end can take on a smaller wristpin size.

One thing to note is as the small end bush wears out the rod wobble will start to cause wear and tear on the big end bearings too as it starts to ride on it's edges.

Bearing wise cheap option ACL H Duty bearings for sub 1.5bar engines or my personal preferred but a lot more expensive Sputter bearings by Kolbe Schmidt which are less susceptible to crushing and have a special design to have a slightly thicker film of oil at the main pressure point for big turbo engines.

If I had to choose I would always opt for rifle drilling for longevity like your factory VAG rods.

As for the other bits Stock valves are good for 500+hp only if the guides have been renewed and seats recut and valves refaced running with shimmed stock springs or uprated ones to prevent valve float from exhaust back pressure under load. Failure to do so and any deflection of the valve will eventually cause them to drop irrespective of the power level one is running. Uprated one piece valves from aforementioned companies basically allows someone to do a bodge job and not replace the exhaust guides and not having to worry whether the valves will fail.

hth JP

 

[Willie]

How about the IE 144x20 rods? They can be rifle drilled for an extra £75 straight from IE.

Fair bit of difference of opinion out there around rifle drilling, some say yes, some say don't bother until big power, others say don't bother but put the extra money towards a really good set of rod bearings...

IMO Willie, for track work which involves alot of bends, braking, acceleration - G-forces which will have your oil all over the place even with a baffled sump, I would say rifle drilled rods are a must to ensure constant lubrication and cooling of the wrist pins under track conditions. Get ACL rod bearings too while you're at it. Non rifle drilled rods and OE bearings are fine for fast road use but not the track.

As Craig said, exhaust valves can be a weak point, same with high temps in the K04 turbo which WMI helps reduce. ARP stud and nuts for the head are worth considering too, rather than OE stretch bolts. The OE hydraulic timing belt tensioner can also fail under hard use (or any kind of use!), so the manual tensioner kit is well worth considering too.

Why not speak to Issam at INA - I'm sure he would do you a good deal on everything you need?

This is all just IMHO of course, but I did research all of this when rebuilding my own engine.

I was pointed towards this thread by someone who was showing concern on their choices.

Basically Your wrist pin is supported by brass alloy bush this has oil distributed onto it by the 3rd oil scraper on your piston and your oil squirters for lubrication. When applying any sort of force this load is directly applied to the bush causing it to wear irrespective of the volume of lubrication. The bigger the diameter of the wristpin the more the load is spread out and the longer the bush lasts.

Alternatively you get the rods rifle drilled so now the wrist pin is no longer being supported by the bush but a pressurized oil layer like the rest of the bearings and moving components in your engine. Reducing the amount of wear and increasing the load the small end can take on a smaller wristpin size.

One thing to note is as the small end bush wears out the rod wobble will start to cause wear and tear on the big end bearings too as it starts to ride on it's edges.

Bearing wise cheap option ACL H Duty bearings for sub 1.5bar engines or my personal preferred but a lot more expensive Sputter bearings by Kolbe Schmidt which are less susceptible to crushing and have a special design to have a slightly thicker film of oil at the main pressure point for big turbo engines.

If I had to choose I would always opt for rifle drilling for longevity like your factory VAG rods.

As for the other bits Stock valves are good for 500+hp only if the guides have been renewed and seats recut and valves refaced running with shimmed stock springs or uprated ones to prevent valve float from exhaust back pressure under load. Failure to do so and any deflection of the valve will eventually cause them to drop irrespective of the power level one is running. Uprated one piece valves from aforementioned companies basically allows someone to do a bodge job and not replace the exhaust guides and not having to worry whether the valves will fail.

hth JP

Awesome information guys, thank you to all who have spent time and effort and sharing their knowledge and experiences.
My car will never be over 400 BHP and 400 ft-lbs.
I would like to build the rods to cope with this and sustained track use.
As for the head and pistons, just now, unless there are any damages found on removing the rods, I'll rebuild this with the OEM ones with new rings and maybe buff up the piston bores too.
Anything else you guys can think of that I need to consider taking into what I've written above please reply here.

Much appreciated all

 

[INA]

Fair bit of difference of opinion out there around rifle drilling, some say yes, some say don't bother until big power, others say don't bother but put the extra money towards a really good set of rod bearings...

Whenever Rifle drilling is an option use it.
You can never have enough wrist pin lubrication which basically feeds off from oil being sprayed through the squirter and "splashing" off the under crown of the piston.

If you need any internals let us know

 

[wild willy]

Its interesting that Jabbasport, JBS and Backdraft motorsport continue to use non riffle drilled rods as the rod of choice for rerbuilds. Some builds have more than 70,000 miles (400bhp)on the clock with no signs of wear when stripped down and checked. I do know that at least one person has experienced rod rattle that was due to ineffective wrist pin lube though.
Most aftermarket rods i've seen rifle drilled do appear to have a smaller drilled hole than stock though which is substantial. IE non riffled rods do have 3 holes drilled in the small end for lube which stock rod and most riffled rods dont have probably to prevent the pressurised oil from escaping.
The point at which the wrist pin supports the piston on either side relys on windage / splash lube only. The wrist pin does not rotate a full 360 degrees is simply rotates from side to side.
Many high powered BMW cars rely on splash lube only.