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VVC Engine rebuild
http://www.gtmdrivers.com/forum/vvc-engine-rebuild-t3240.html
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Author:  sanzomat [ Sat Oct 10, 2015 10:10 pm ]
Post subject:  VVC Engine rebuild

Well, I'm finally making some progress with my engine. It only took me 5 months to move it from the pallet to the shed so the progress since then is flying by comparison.
I got the head off a couple of weeks ago and have now managed to get a bit of port work done. It's my first go at this so was a bit nervous but wanted to give it a go and having looked at lots of pics and vids I thought "how hard can it be" Decided to go for a basic removal of the rough bits with just a small amount of metal taken away around the valve guides and bifurcation. The valve guides were chipped with some biggish chunks missing, especially on the inlets. No sign of where the bits had gone or any damage from them having rattled around in the combustion chamber so I wonder if they were chipped while being installed. Whatever, the pics I'd seen of peoples porting projects had all shown the guides ground back to the alli so that what I did too. Here are a few before and after pics. Not sure how much benefit it will give but it was quite fun having a go.

Exhaust - before: (I'd given the right hand valve a bit of lapping before taking this as this is the cylinder that was down on compression. Seemed to lap up okay so all will be lapped as the next job.
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Exhaust - after:
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Exhaust after.jpg
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Inlet - before, note chipped valve guides:
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Inlet - after:
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inlet after.jpg
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Exhaust Port - before:
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And after:
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Inlet port - before:
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Inlet port before.jpg
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And after:
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Author:  catsam [ Sun Oct 11, 2015 5:40 pm ]
Post subject:  Re: VVC Engine rebuild

Looking good

Author:  sam [ Thu Oct 15, 2015 11:05 am ]
Post subject:  Re: VVC Engine rebuild

Looking good so far, it will be interesting to see your progress on this as my engine is failing emissions at the moment and it looks like I will need to replace it (space and time permitting), a good opportunity for me to try and improve the original.

Have you got a plan as to what you want to do to the engine ultimately?

Sounds like you have already done a fair bit of research so you have probably come across Dave Andrews site about tuning the k series http://kengine.dvapower.com/ seems to be quite a thorough look at the possibilities.

Happy fettling..

Author:  catsam [ Thu Oct 15, 2015 11:56 am ]
Post subject:  Re: VVC Engine rebuild

hi

Quote:
Have you got a plan as to what you want to do to the engine ultimately?


are right the plan.
when i got my k3 it had been rebuilt by advantage998 k3-rebuild-t2045.html
he had done a grate job with the rebuild and i was looking for a project to do so thought i would change the r65 gearbox to pg1
then I found out that The pg1 uses a unique starter motor and flywheel/clutch to the r65 and cannot be swapped.
The PG1 can be fitted to the 1.6 engine but must be fitted with the pg1 flywheel and starter from a 1.8 engine. so it seemed a good idea to change the hole engine and box
now to the point i had no plan to do anything with the engine with 143 BHP i will see what its runs like

Author:  sanzomat [ Thu Oct 15, 2015 2:03 pm ]
Post subject:  Re: VVC Engine rebuild

My original plan was simply to swap my 1.6 for the 1.8VVC, but nothing is ever that simple. I don't really like the imprecise "rattle rod" gearchange on the R65 box so decided to go with a PG1 and use the MGF cable change. That also means MGF driveshafts too.

I managed to source an engine (with starter motor, alternator, manifolds, injectors etc), gearbox, driveshafts, cable gearchange mech/linkage, ECU, 5AS/fob and complete engine wiring loom all from a '98 MGF with a claimed 68,000 miles. Claimed to be running fine and with an intact head gasket.

As the engine was separate from the car I thought it would be worth giving it a once over before installing as I didn't want o fit it and then find it was a bag of spanners.

I figured a new water pump and cam belts would be a sensible precaution. I then thought I might as well take the head off and check it out. Before doing so I compression tested it and one cylinder was a bit down - possibly the valves were left open on that one whilst it was sat for 5 months on a pallet under a tarp! That decided it, the head was coming off.

Whilst the head was off I thought I may as well have a go at the ports. Mainly because I wanted to have a go at it and as long as I didn't break anything it was effectively free. I had no real plans to increase the power but if it does give an improvement, I won't actually know as it will be lost in the general increase from the bigger engine. Hopefully it won't make things worse. I've no plans to change the cams or upgrade/remap the ECU so there is a limit to how far to go. If Ifind myself wanting more then there are other options for the future. Other than the slightly leaky exhaust valves (just needs a bit of lapping) everything looks pretty good inside.

I am aware of the guru Dave Andrews and I've read some of his stuff. I know a couple of guys from the Bristol Kit Car Club who have both gone down the DVA head upgrade route - one on an Onyx Firefox, the other on a Marlin 5exi (now written off) If any one is interested Dave Bence's build diary and subsequent upgrades http://www.davebence.co.uk/ is well worth a read - his guide and photos on setting up the VVC timing is probably the best on the internet and there are lots of other useful snippets on K series bits that transfer well to the world of GTM.

I'm currently trying to convince Ken to part with his DVA modded head as its pretty much all thats left from his Marlin after his crash! If I do get it I'll keep this project head as a spare!

The other mod is the Passat radiator upgrade. I've got all the bits and I'll do that at the same time as installing the engine as I'll have to take the front to back pipes out to get the gear change installed!

Author:  sanzomat [ Sun Feb 28, 2016 10:23 pm ]
Post subject:  Re: VVC Engine rebuild

First chance for a proper run out today, nice dry roads and about 6 degrees this afternoon so went out for a bit of a thrash. Wow! Can't believe how much quicker the car is with the VVC engine over the previous 1.6 K Series. Not sure whether my DIY port work is helping much but it is certainly pulling very strongly and flies up to the rev limiter at 7200. Makes a lovely noise and really gets into its stride from about 5k and then just gets better and better. All this with a 48mm throttle body too - I thought it was a 52 'cos its an alloy one but I found out they did alloy 48's too and this is one. Got a 52mm TB on order so maybe even more to come!

Remarkably it seems to be giving better fuel consumption too!

The TF steering rack is also a real improvement. It feels much better weighted when pushing on and the steering inputs just feel right.

The gear change is great too.

The temperature isn't getting above about 80 degrees on the dial - might mean the sender isn't matched properly to the gauge but I didn't notice the fan coming on (fan thermoswitch is something like 92 on 86 off from memory). As its pretty cold weather it might be accurate and I did drill the thermostat to prevent thermal shock so might have drilled too big a hole!

Have to say that I'm really chuffed with the upgrades. Can't wait to try it out on track. Castle Combe booked for 25th April :D

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