K Series mods for an S2 111s

Hi and greetings all. I mainly post on pistonheads, but from reading many posts here, there definitely seems to be a lot of really knowledgeable folks who use exiges.

I have a 111s S2 and have been exploring all sorts of options regarding engine upgrades. At the end of the day, a honda conversion seems to be the only viable engine conversion for the S2 at the moment. However, increasingly I have been considering upgrading my k series engine.

The two options at the moment seem to be either modding my current vvc engine, or looking for a vhpd engine that has been replaced by eg a honda and having this worked on.

Essentially I am looking for decent torque and driveability rather than an all out top-end screamer. To up the rev limit on the VVC would mean pistons and con rods (at least as I understand for the newer vvcs which have less sturdy con rods than the older engines). I thought to consider a 1.9l scholar block with the existing crank etc, followed by head work, porting and decent cams - current recommendations seem to be the BPH 285 cams. If I find a vhpd engine, the advantage would be that I would not have any time constaints while the engine was being built, they engine would already have throttle bodies (DTH) and would not need vvc blanking etc.

Has anyone got experience of this sort of setup? THe next issue would be the compatibility of an emerald ECU and wiring looms from a vhpd engine to the S2. I would likely need a decent manifold as well.

Without going bonkers with a stratospheric rev limit, can one get decent power and torque from such a setup and is it practical in terms of cost vs performance.

Thanks all

Hi Andrew and welcome to the board.

Well you certainly know how to open a can of worms, and with your very first post!! lol

The Honda conversion is loved on here and with good reason, the engines are pretty cheap and readily available, it gives great drivability and you have the top end when you want it. Personally I think the costs that are banded around for the drive in drive out Honda conversions are pretty high, but I am probably missing the point or something.

If you want low down torque and drivability then the Audi turbo route or SC honda are the way to go. The Audi engines are also cheap and very readily available, although with it being a turbo install there are a few more things to think about, cooling being the major one.

I am a bit of a K series die hard and am having an all singing all dancing race engine built at the moment. My reasons for this are I don’t really use the car on the road, so ultimate drivability is not important, weight is a big issue, I don’t think anything is as light as a good lightened K and in the mid engined car stakes keeping as much weight off the back as possible is the name of the game in my opinion.

Agian in my opinion with a normally asperated engine you can’t really have your cake and eat it, by that I mean you cant have good low down drivability and lots of top end, but you can come to a half decent comprimise.

Your plans for the K sound good to me, although it wouldn’t be my choice, but I’m not going to go into that on here as it is far to political. I’m sure you will get the jist if you read through some of the other threads.


Thanks Sean, I am certainly not knocking the honda conversion or trying to stir anything up. In all likelihood, I may well end up with the honda conversion. Methodically though, I am trying to look at all the options.

At the moment, the honda conversion is the only one available for the S2, so the duratec / audi etc can’t really come into the equation. I am a little concerned that they have ceased production of the Civic type R her- I don’t know what that will mean for the availability on engines in the future. I am sure JDM engines will be available to import. That said, I do like the honda conversion.

I thought as a middle of the road option, that k series mods were worth considering. I have read literally hundreds of posts about this - even some of the really famous/infamous debates (long one too) about k series engines. The actual cost of changing to a 1.9l open block is not substantially more than upgrading the pistons etc on the current block. It does however offer torque benefits out of proportion to the capacity incease. Aiming for 210 odd bhp from a 1.9l K should allow decent driveability (bearing in mind that the standard vvc isn’t exactly a torquey engine in comparison to say a duratec) As long as the idling is ok and that from 2500 rpm, the car is driveable, that would do the job. Also, having an increased capacity means that the power will be more easily achieveable without going towards really high rev limits as I understand from discussions with Dave Andrews and KiwiRog on seloc.

If this sort of engine could be done for say a little over half of the cost of a honda, it might be worth considering. I have already done several mods to the rest of the car in terms of brakes / suspension / oz’s and 048’s / quickshifter / HID’s, so it should be ready to take on additional power, rather than sell it and buy a converted car. I am not a fan of the toyota engine in terms of the power delivery - it really doesn’t suit my driving style.

I am still not clear on the compatibility of the wiring looms / emerald etc for the S2 at present. If it is a huge stumbling block, then a converted K may well have to join the ranks of the options I have already excluded.

BTW Sean - didnt you have a long thread going a few months back regarding your converting your exige to a race car? Really interestin iirc - I don’t think some folks (myself included) had appreciated how much work was involved.

Thanks all.

It is straightfoward to graft the Emerald onto an S2 loom, the only caveat is that if you are operating the VVC mechs using an Emerald then you will have a problem with the water temperature guage. For all other applications the Emerald is just fine and supports the speedometer and water temp gauge as normal.

The soldering takes about 2 hours and a MEMS connector costs around �20, the pinouts are readily available, I have connected around a dozen to the S2.EU3 loom with no issues.

It really isn’t a problem.

Emerald did at one time make a plug in adaptor, however the manufacturer of the connector used will no longer supply them so they can no longer make the adaptors.


Thanks for clarifying Dave. Looking at some of the dyno graphs that are available, it certainly seems that there are a load of options. It sounds like the most feasible option for my puposes, will be a setup like your K06 kit, but with the scholar 1.9 open block and pistons and possibly a new manifold. Should make for a plenty quick road and trackday car.

if you are lifting the head then you can use better cams than the K06 provides since ou can fit springs that accept more lift, you can also lick the head over a bit… a 1900 to that sort of spec should do 210BHP+ and 160lb/ft+ even on BP285H cams.


Dave - If I was to consider an engine rebuild from an old engine (ie keep my vvc as is and allow the car to stay on the road while building take places, thereby removing the time factor etc), what engine would make the most sense as a starting point, bearing in mind that pistons and block would be replaced? VVC engine form a mark 1? (better quality conrods I belive - could one retain these on a 1.9?)Any others to look out for?

Going for a VHPD seems an expensive starting point if one it junking the pistons. With the number of engine conversions being done, there seem to be a load of old k’s floating around. As I may very well be asking you for more detailed advice and hands-on expertise, I value any advice on this.


An early VVC would make most sense, there is a high probability of single tang rods and the head is a good starting point. double tang roids can be made to work OK with some modifications to the bearing location though.

Any early engine should have decent rods, VVC or not.

The stock crank and rods, if properly balanced are good for 7800-8000 and in 1900 guise that is enough for over 220BHP so you dont need any exotic parts.


Thanks a ton - I will likely be looking around for an old VVC then - I am sure this would make the head work easier. If I ended up with close to 220 bhp and decent torque with the mods and manifold, I would be very well chuffed. I would be happier with a slightly conservative rev limit in the interests of keeping the stresses a bit lower.

I’ve gone the upgraded K myself and think your target is achievable without too many problems.
Good balancing, and top liner clearance should keep the high RPM gremlins away.

If you are only after 210BHP you don’t have to do much at all. My car currently runs an internally totally standard VHPD. The only changes on my car are the Emerald ECU, Jenvey throttle bodies and a full Elise Parts exhaust and manifold. That spec made 206BHP on Dave Walkers rollers.


I thought you had some DVA stuff on yer heid ?


Not wishing to be controversial, & just for clarity, is it reasonable to say Emerald ECU, Jenvies, Exhaust/manifold & mapping at Dave Walkers would cost in the region of �2400 (if you fitted the “hardware” yourself} & approx �500 more if you employed someone else to do the install?

Figures based upon ECU �400, Jenvies �600, Exhaust stuff �800, Mapping/rolling road �200, all plus vat.

I thought you had some DVA stuff on yer heid ?

I remember he mentioned at that moment it was all stock Rox.
Except he had the bigger airbox and longer trumpets

And Sean, totally std VHPD still has a few differences with a stock VVC, namely forged pistons, solid lifter cams, TB’s and a lighter flywheel (AFAIK)


Not wishing to be controversial, & just for clarity,

yeh right faither…

yeh right faither…

Sorry Rox, I thought that you Jocks in particular were interested in the cost of things?

The costs & details of what’s included in the various packages of the alternatives to the K series, are openly available. With the Honda & Audi packages for example, there are 2 or 3 different states of tune/power, & their relative costs are openly advertised. However, there are so many different packages for tuning the K series, that I think it is therefore reasonable to know the “ball park” cost of a specific package for tweaking the K series.

I honestly don’t think I am being controversial, by simply asking how much something costs. It is for others to decide whether or not any of the alternatives is value for money. However, without knowing the cost of what you’re getting, how can that evaluation be made?

It is no secret that I’ve gone Honda - that was, I felt, the best decision for “me” at the time, & nothing to date has altered my opinion one jot. I totally respect the decisions of MikeL, Mr Admin, SeanB, Uldis, Maddog etc, who have made their own choices as to what they consider to be the best for themselves. God forbid we all agree on everything, that really would make things boring! Let’s have an open debate on all things Exige - a bit of banter/pi$$take is all good stuff in my book, but falling out/mud slinging has no place here.

Sorry, I’ve gone off on a ramble - you can all bollock me & get your own back at Donington on 29th April

Yeah Pesk, I guess your prices are in the ball park. From memory the Jenveys were about �500 and the ECU was about �450. The exhaust with the manifold and silenced decat pipe sounds about right.

No I don’t have any DVA stuff on my car. It is a stock VHPD.

Uldis, I understand the VVC differences, I was just stating what I had and that you didn’t have to do anything internally to get over 200bhp

I’m with Pesky on the each to there own front. I agree the world would be a dull place if we all ordered the same sandwich!!


Figures based upon ECU �400, Jenvies �600, Exhaust stuff �800, Mapping/rolling road �200, all plus vat.

Emerald ECU (with ancillaries) is �550 +VAT and rolling road is �250 +VAT - so add a couple of hundred more to your pre VAT costs.

Ta Steve.

Uldis, I understand the VVC differences, I was just stating what I had and that you didn’t have to do anything internally to get over 200bhp

Sorry, I appeared to have mentioned it to you, when I now you know.
The comment was directed as a clarification on your comment to Shangani, but hey, it looks like I made a shambles of it!