My winter Workshop project - a more modified head for my K series Freelander 1.

I have interesting plans but I am wanting some guidance and advice. My aim is to enhance and improve the torque characteristics of the motor. I certainly don’t want it to guzzle more fuel or hamper it’s current performance. I hope to make it a bit more frugal on fuel and give it a more power. I’ve found that when passing it’s not very good at accelerating from about 80kmh in 4th, or pulling up a hill at 70kmh and trying to accelerate, even in 3rd gear

But first some back ground.

Some will recall when I acquired my FL1 in early 2014, an 1800cc K series five door which was a non-runner, and the process of getting it on the road again. I gained a lot of pleasure and knowledge in doing that, and I love to tinker with things which is just as well when we own a Land Rover!

At that time when I refitted the head I had taken the opportunity to do some minor mod’s to the motor which I believe collectively added to general reliability, economy and performance. The things I did were inspired by the article/s from the K Engine page, see this link. Not in any order of priority or importance, they include:

• flowing the oil pump
• fitting the strengthened bottom oil rail,
• removing and welding splatter from the ex manifold & front pipe,
• de-cat pipe fitted,
• removed the plastic ‘flash’ from the inlet manifold,
• removing the thermostat and fitting a PRT to the top hose,
• some head work including un-shrouding the valves by 2mm,
• trimming the back of the valves themselves [ a 30º ‘back cut],
• trimming back the lower side of the valve seats to remove the step, or lip, due to misalignment of the seats to the casting,
• trimming down the valve stem boss and the valve guide and opening up the runners by maybe 1mm or so as well as slightly enlarging the inlet/ exhaust ports,
• built a cold air feed for the motor and swapped out the st’d air filter for a K&N Apollo one.

With the exception of the head skim, valve un-shrouding and back trimming the valves I did all the work myself.

Since then I have acquired some useful spares including two complete motors, a standard 1800cc and a VVC one and a spare head. Except for the VVC the other heads are serviceable. The standard motor has been on my engine stand for over a year and it’s time I ‘got on with it’! It has one liner which requires to be resealed into the block, the head reassembled, refitted and away it should go. I have plans for that motor too - but another time.

I am familiar with the process of replacing a blown head gasket and have come to agree with many that it’s best to view the HG as a service item which needs replacing periodically. My coolant level has been fluctuating over the past few months and now I see coolant staining below the ex manifold - That time is very near. Other than that the car is running very well.

My project is to modify the spare head and then fit that to the car when I replace that HG. As before the work I’m considering is based on the suggestions from that K-Engine page. The work could include:

• replacing the valve guides [ I know the current ones are worn]
• unshroud the valves by 1.5mm [and blend those areas into the head],
• put a 30ºback cut to each valve,
• remove the ‘knife-like’ edge and put a round edge on the valve,
  • - except for that blending, the work will be by a specialist head workshop,
• As before I’ll trim down the valve guide protrusion as well as the ‘boss’ around the guide,
• correct alignment issues at the bottom edge of the valve seats,
• remove, or round off the ’step’ where the valve insert sits in the head,
• polish the combustion chamber surface,
• polish the exhaust throats, runners and port areas,
• Fit the VVC Cam followers which are the later type
• minor valve throat, runner and port resizing.
• I’ll check to see if there is a difference in the Inlet port size and the Exhaust manifold pipe size and match up more closely if possible.

I could also fit some parts from that VVC head and they would include:

swapping the valves over as there are 2mm larger and according to that article they will fit the standard valve seats. [st’d inlet = 27.5 Vs VVC 29.5 & st’d Ex = 24mm Vs VVC 26mm]

Question #1 - Will the seats need to be recut and valves ground to suit?

Question #2 Will I have to trim the length of the valve stems?

I’ve the VVC intake plenum and throttle body as well so I could fit that too. Again I’d have to see how well the ports align and match for size. Will it give benefits?

Would there be a benefit in fitting the VVC inlet cam? Does it have a longer duration = more air/fuel in?

Would the st’d inlet cam work better with those bigger VVC valves [29.5mm]? OR would the VVC inlet cam with the st’d valves [27.5mm] be better with its longer duration?

I’m not looking for a high reving ‘race’ engine where power is developed at high revs. But making it breath better must help in improving torque and general performance & economy.

Other mod’s I’m thinking through which could help me but cost quite a lot: vernier pulls to optimise the timing - but I have to learn a lot more about the ins and outs of that. Having some extractors made which enhance torque in the low to mid range ie: long primary and secondary pipes…

I think I understand about porting and making things bigger… Larger airways are required in a high revving engine as there is a considerable amount of gases moving in and out. In a low revving engine those larger pathways would be a disadvantage as the gas movement would be slower? So would the st’d set-up work better in my situation, save for some minor resizing & reshaping?

I guess the question really is: would the ‘stock’ head, albeit smoothed out as above, be the best arrangement?

Here are some options below: In your opinion which is best and why?

Option #1
some modifications - valve guides & bosses trimmed, valve seat alignment smoothed, minor runner work, exhaust runners polished, better port size matching / alignment with their manifolds, valves un-shrouded 1.5mm and then blended into the combustion chamber, valves back trimmed 30º and edge rounded, valve insert lip removed, combustion chamber polished, VVC cam followers,

Option #1A
Fit VVC intake plenum and throttle body

Option #2
Stage 1 modified: Valve guides & bosses trimmed, larger VVC valves fitted [seats recut and valves ground, 30º back cut and edges rounded, Stem length checked], valve seat alignment smoothed, open up valve throats [inlet + 3mm? Ex + 2mm], runners to ports enlarged and concentric - exhaust runner polished, better port size matching/alignment with their manifolds, valves un-shrouded 1.5mm and then blended into the combustion chamber, valve insert lip removed, combustion chamber polished, VVC cam followers,

Option #2A
Fit VVC intake plenum and throttle body

Option #3
Stage 2 modified: Valve guides & bosses trimmed, larger VVC valves fitted [seats recut and valves ground, 30º back cut and edges rounded, Stem length checked], valve seat alignment smoothed, open up valve throats [inlet + 3mm? Ex + 2mm], runners to ports enlarged and concentric - exhaust runner polished, better port size matching/alignment with their manifolds, valves un-shrouded 1.5mm and then blended into the combustion chamber, VVC inlet cam fitted, valve insert lip removed, combustion chamber polished, VVC cam followers AND VVC intake plenum and throttle body fitted.

You lost me very early on

If you want to increase low RPM torque, then you need short duration cams, and probably get a remap too.

The VVC head is a good option, however it requires a VVC ECM for it to function.
The VVC head does provide a few more ftlb of torque at low end, but also allows better breathing at high RPM.
Fitting the VVC plenum and throttle body will improve throttle response, but won't increase the torque much over standard, but any improvement is better than none.
I think I'd be concentrating on finding some short duration cams, which will improve low RPM torque, although at the expense of higher RPM power.

My performance experience isn't with the K series, but older push rod engines.
However @rob_bell is an MGF racer, and has loads of tuning experience for the K series.

I won't use the VVC head as it's 'soft' I was thinking of removing the valves and fitting them to the standard K16 head which cam off an MG.
I was in error when I said about using the VVC inlet cam/s I should have said the exhaust cam.
Are the standard FL1 cams the better option as FLI power curve graph shows max torque at about 2700rpm?

GrumpyGel said:

You lost me very early on

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Ah yes too long eh?
Just seeing what advice is out there to guide me!
Option 1 looking good!

htr said:

I won't use the VVC head as it's 'soft' I was thinking of removing the valves and fitting them to the standard K16 head which cam off an MG.

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Don't use a soft head, but the valves might work OK.
For torque, you need to keep port gas velocity up, so small ports would be preferable.

htr said:

I was in error when I said about using the VVC inlet cam/s I should have said the exhaust cam.

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I did wonder how you were going to get the 2 piece inlet cam of the VVC to work.

From memory, the exhaust cam of the VVC is shorter duration, which is good for torque. I'm thinking it would be possible to use the VVC exhaust cam in the inlet and exhaust, which should give a shorter duration than the standard FL1 cams.

htr said:

Are the standard FL1 cams the better option as FLI power curve graph shows max torque at about 2700rpm?

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Yes I've see this in the past, but never found any definitive information on cam timings for the FL1.

Browsing Mr Bell's article here, I noted that the cam numbers for the 135 upgrade to a st'd 1.8 head are the same as the stock cams for a FL1 as listed on rimmers. Interesting - I'll have a gander at the cams that I have here. Below is the table of data from that article. Question: Does anyone have the information on the stock FL1 cams? does it differ by much?

The standard 1.8i car cams are classic symmetrical timing, 12-52-52-12, which many manufacturers have used for decades to give a good spread of power throughout the rev range. We'll call this the datum or standard timing, to safe confusion later on.

The 115/135 cam is using asymmetrical inlet and exhaust timing. The inlet is opening 1° earlier, and closing 9° later, give 10° longer duration. The exhaust is opening 1° later and closing 9° later, giving 8° additional duration, but shifted to slightly retarded. The 115/135 cams also give 0.70mm more lift than standard, which means faster valve opening, which helps allow more air in.

As a rule advancing the cam timings of both cams, will increase low end torque, but at the expense of high RPM power. Retarding the cams would increase high RPM power, at the expense of low RPM torque.
Because the K is running separately inlet and exhaust cams, the timing of the inlet and exhaust can be optimised for maximum torque, or power if needed.
The hardest part will be selecting the cams that work for your given application.

I'd be tempted to try the 115/135 exhaust cam in the inlet, with the standard exhaust cam.
This will give a 9° earlier inlet valve opening, and open it wider, but close it 1° earlier.
I think there should be sufficient clearance between the valve and piston to accommodate this, but you'll need to trial assemble the engine to be sure.

I was thinking carefully about my 'option #1' above but exploring the possibility of adding in the VVC valves [valve grind and seats recut] and in light of what you suggest dropping in that inlet cam. Essentially leaving the runners & ports as they are but just cleaning them up a bit.

This would seem to suit me as I seldom get over 4000rpm and that only happens when I pass in 3rd or 4th gear which is generally rare. I'm hoping to see improved pulling power at low speed as I described above and maybe a small improvement in mpg / km/l - that would be nice too.

Just to clarify two points, those larger valves will work with the existing standard valve seat inserts? And 'ports' means the area made up of: the valve 'throat' which is immediately below the valve and is where the valve guides and cast bosses are, the runner is the channel from there including the biurification and out to the actual point of exit from, or entry to, the head which I think of as the 'port'.

Thank you for sharing your knowledge and experience, it's very helpful.

I need to go back and read the whole thread in detail (apologies, I am at work!) but (a) what a great project! and (b) there's plenty that can be done.

I know Dave Andrews pretty well (compaired to New Zealand, Dave is in Milton Keynes and is practically a neighbour). I actually have had a couple of cylinder heads ported by him - including a "fully monty" VVC ported head with DTH Jenvey throttle bodies - an engine to build this winter once the garden workshop is finished

If this were my project on an FL1, I would want more torque low down and into the mid-range. If not going the supercharger route (actually you could consider that!) and keeping normally aspirated, I would keep standard cams and valves. Most porting work improves top end breathing - which is great if you are going for a high-rev engine - but that may not be what you are aiming for on your FL.

The two simplest things would be a re-map (the engine in my FL1 feels very different to that in my MGF - and that may be ECU mapping) and to fit a good, long primary and long secondary 4-2-1 manifold. Honestly, on the standard engine, a 4-2-1 exhaust manifold really transforms bottom end performance. I was hoping to find a decent one from an MG ZR (Janspeed, Piper etc all made them in the day and they come up on ebay from time to time on the UK bay of fleas) - but there are differences between this and the exhaust arrangement on the FL.

If you really want to push low-mid range torque, then I'd probably go with a supercharger (Rotrex or Eaton - you may be able to get away with standard internals so long as you aren't too greedy with boost) or I guess a small, quick-to-spool turbo? But those projects are rather more expensive to pull off...

Supercharging - now I have to admit I hadn't thought of that!

Basically I'm going to have to take the head of my FL1 as there is a coolant weep below the exhaust manifold and I'm having to keep a very close watch on it and top up about 100ml, that's close to the 'Low' to the 'High' mark. I have spare heads, one of which is a soft VVC one from a Rover 200Vi. I know my block / liners are uneven in height, one is pretty much flush with the block’s face. I use the Payen BW750 HG

I want to have a head totally ready and to swap it over one weekend soon. Nodge suggested using the exhaust cam from the VVC engine as the inlet cam in the FL head as it would give a bit more lift and greater duration, the exhaust cam would be st'd. I could either leave the st'd FL1 valves in or swap them over to the VVC valves: valve seats recut to suit and valves ground. I'd also have the little bit trimmed off the back of the valves to help gas flow. The head I plan to use needs the valve guides replacing and I have a set on hand.

The only head work I'd do is: unshroud the valves 1.5mm and blend that into the combustion chamber, check the valve seat alignment and correct any misalignment, remove that right angle edge on the seat inserts in the combustion chamber and give it a polish to a smooth surface along with the exhaust runners to the ex port. Trim down the valve guides and the bosses as well. No other work on the runners / ports as I believe that smaller size is better for a lower torque range and and lower revving engine except to remove any obvious problem areas.

My thinking is based on an article I read many years ago about a morris minor called the Miller Morry. That fellow use pretty much bog standard parts and bolted them onto his motor - at the time it would give GTi VW Golfs something to think about I just love that idea of using pretty much st'd parts to enhance an otherwise st'd motor.

You have a lot of experience in the tweaking of the K series so I'd really welcome your inputl.

Nodge68 said:

The standard 1.8i car cams are classic symmetrical timing, 12-52-52-12, which many manufacturers have used for decades to give a good spread of power throughout the rev range. We'll call this the datum or standard timing, to safe confusion later on.

The 115/135 cam is using asymmetrical inlet and exhaust timing. The inlet is opening 1° earlier, and closing 9° later, give 10° longer duration. The exhaust is opening 1° later and closing 9° later, giving 8° additional duration, but shifted to slightly retarded. The 115/135 cams also give 0.70mm more lift than standard, which means faster valve opening, which helps allow more air in.

As a rule advancing the cam timings of both cams, will increase low end torque, but at the expense of high RPM power. Retarding the cams would increase high RPM power, at the expense of low RPM torque.
Because the K is running separately inlet and exhaust cams, the timing of the inlet and exhaust can be optimised for maximum torque, or power if needed.
The hardest part will be selecting the cams that work for your given application.

I'd be tempted to try the 115/135 exhaust cam in the inlet, with the standard exhaust cam.
This will give a 9° earlier inlet valve opening, and open it wider, but close it 1° earlier.
I think there should be sufficient clearance between the valve and piston to accommodate this, but you'll need to trial assemble the engine to be sure.

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That is an interesting idea! Personally I'd probably do that cam side as the next step. I'm quite keen on option #1 above but with the larger valves installed and the back trimming done too. Only one way to find out really and that's to give it a go. Like I said, it's my winter project so I'll let peeps know how it goes.

'Winter project' is now well underway. I got a scrap head to practice on and now I'm well into modding the head I'm going to swap over. Exhaust side mostly done and I've started on the inlet side. I'll send the head off to have the valves unshrouded 2mm, the valves given a 30º back cut and their radius edge rounded and the head skimmed to compensate for removing the material in the combustion chamber.

I used an old HG to cover the head surface to give it protection - this head had already been skimmed. Lip removed around the valve seats. The valve seats enlarged to 21.5mm for the exhaust and to 25mm for the inlet.


In this pic you can see I've trimmed down the inlet valve guide and its 'boss'.

A close-up of the exhaust port - basically ready to go. I've enlarged the port to 20.5mm from about 19mm width. It is not a big change but it will be interesting to see how this goes.

Tools for the job: die grinder [ have to be very careful with that!], an old set of valves from the scrap head - I use these to check the size and if things are concentric. Stock valves are 24mm & 27.5 are being kept.

The bulk of the work I've done with my Dremel, its slow but you can't make to much of a stuff up with it.

Dremel bits: left ones for cutting alloy, right ones for steel... sanding discs for the combustion chamber.

My collection of die grinder burrs & sanding cones / cylinders. I use the latter in an electric drill with an extended chuck which I had made. The Buffs are really good to finish with: 120grit, 180 grit, 300 grit & 400 grit.

Still waiting for some parts to come - HG from DMGRS - couriers are a bit slow!
Thank you to @Nodge68 for words of wisdom and @rob_bell for being a 'sounding board' for my ideas, encouragement and ideas.

How I wish there was a good forum like this for Ford Cortina Mk1s!!! I've been doing all sorts of interesting things like rebuilding gearboxes and makimg new looms with fusing and relays and just about to start on the engine and no bugger to share it with!!! Forums are either like graveyards or involve major refurbishment work like what door mirrors to fit!! Arg+hhhhh

andyfreelandy said:

How I wish there was a good forum like this for Ford Cortina Mk1s!!! I've been doing all sorts of interesting things like rebuilding gearboxes and makimg new looms with fusing and relays and just about to start on the engine and no bugger to share it with!!! Forums are either like graveyards or involve major refurbishment work like what door mirrors to fit!! Arg+hhhhh

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put it on here as "members vehicle project" there would be loads of interest and advise/encouragement.

J

andyfreelandy said:

How I wish there was a good forum like this for Ford Cortina Mk1s!!! I've been doing all sorts of interesting things like rebuilding gearboxes and makimg new looms with fusing and relays and just about to start on the engine and no bugger to share it with!!! Forums are either like graveyards or involve major refurbishment work like what door mirrors to fit!! Arg+hhhhh

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I've found car forums tend to be dwindling across the board, gone are the days of every section being full of interesting threads like this, these days they seem to be populated mostly by "HELP!!! my car won't start" sort of threads, so any content like this thread, or your gearbox is a welcome relief.

@htr GREAT WORK!!! I can't comment with any authority on the head work required to make the car go in the direction you want, mid range driveability, but I can say that after you've finished the metal work, you might need to remap the car to make the most of the headwork you've done. You might also get better spray pattern out of the injectors by increasing the fuel rail pressure and reducing the pulse width accordingly to keep the balance of the AFR? By that I mean to say still aim for being stoichiometric or slightly lean, but do so with a short high pressure injection of better atomized fuel into the inlet runner rather than a lower pressure longer sprinkle of fuel. Have you considered the bottom end of the engine, reducing reciprocation losses could make the engine feel a bit punchier without force feeding it more fuel. So I'm thinking lightened rods, balanced and knife edged crank, maybe lightened flywheel while you are at it?

htr said:

Still waiting for some parts to come - HG from DMGRS - couriers are a bit slow!
Thank you to @Nodge68 for words of wisdom and @rob_bell for being a 'sounding board' for my ideas, encouragement and ideas

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Good to see you at it again Htr!!
I have a spare VVC inlet manifold and injectors if you're interested, although I am aware that the postage cost could make sending them prohibitive.

This is fascinating. It'll be great to see the results of all this work. It's yet another thread that makes me wish I'd got a garage and a project vehicle.

Thank you all! @Nodge68 I have the inlet set-up on hand. Will I need to swap over the fuel injectors?
I'm going to reshape the inlet port to inlet manifold 'interface' where the castings has a misalignment of about 2mm. I'll trim the gasket to match as the stock ones don't. Will I suffer any loss at that point if I just refit the stock plastic inlet set-up instead of the VVC one?

@Jayridium I have thought about getting the crank balanced but assumed, rightly or wrongly, that modern engine cracks should be pretty good and possibly it would offer little benefit. If I did the crank I'd weigh and balance the pistons and con rods too. Hmm, I've a whole spare engine sitting on my engine stand just waiting... I've yet to refit a piston and liner as I foolishly moved the fly wheel and that liner 'popped' I have a head to go on which I'll mod the same way as I'm going here but without the VVC 135 exh' cam as the inlet. That head is partly done already. I have made an error on that one in that I gasket matched the exhaust ports. So the port is now larger than the manifold opening.

Can anyone comment it that's a killer mistake? The manifold does have a welded lip right where the port meets the head. Is that enough to prevent exhaust gases bouncing back into the ex' port runner?

Remap: tricky as I haven't heard any one in my region who does it. @rob_bell pointed me to Saw tuning in the UK, loved their web site = exciting thoughts!. I could sent them a spare MEMs 1.9 ECU tot week and then fit that but would it work on my cars system? Or would I have to send the actual one on the vehicle leaving me without a car while I wait? I guess their work would address fuel pressure / spray pattern...

Again, my aim is for a smooth running [ balancing could help here] and efficient motor with improved low to mid torque for when 'off roading' and yet will go well when I need to overtake on the highway or head up long hills...

Nodge68 - still thinking about some headers... I see you can buy all sorts of bends Y joints... So I could cut and assemble my own and then have it fizzed together. Hmmm

htr said:

I have the inlet set-up on hand. Will I need to swap over the fuel injectors?

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The VVC injectors flow more fuel, so could well allow more power at higher RPM. However this could be counterproductive at lower RPM, affecting fuel economy. It would need to be tried.

htr said:

I'm going to reshape the inlet port to inlet manifold 'interface' where the castings has a misalignment of about 2mm. I'll trim the gasket to match as the stock ones don't.

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That's worthwhile doing. P
Inlet to port alignment is important for smooth air flow.

htr said:

Will I suffer any loss at that point if I just refit the stock plastic inlet set-up instead of the VVC one?

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You'd need try both manifolds, and see which works best. The VVC manifold is generally larger internally, presumably to get over the plastic manifold shortcomings.

htr said:

Nodge68 - still thinking about some headers... I see you can buy all sorts of bends Y joints... So I could cut and assemble my own and then have it fizzed together. Hmmm

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The K series is well catered for where exhaust manifolds (headers) are concerned, so you could get a good aftermarket one designed for Rover installation, and simply adapt it to fit your FL1, but don't forget the exhaust system, as a lot of power and economy can be lost through bad exhaust design.