S3 205 GTI engine conversion

A 1.9L XU9J4 and 2L XU10J4 (S16 & Mi16) head are basically identical. ie they take the same cams, lifters, springs etc. You can retro fit the XU9J4 head with the later thermostat housing, which allows you to run sequential fuel injection. This makes a significant difference to low-mid range torque. Both heads suffer from the same oil surge issue. You just need to know the limitations.

I haven't been able to identify the Piper Ultimate Road cams in solid. Perhaps you could ask Graham for a part number and/or more specs? Having big cams on a stock bottom end, with only 10.4:1 is never going to set the world on fire. Easily fixed by skimming the block 1mm however. I'd also be asking more about the Meqasquirt 3. There have been issues with 60-2 inputs. You'd be pushing yourself into a corner if you had to run 36-1. It does sound like a bargain however, and the money saved could be put towards a more capable ECU.

It's easy and cheap enough to regrind the cams on the GTi6. Can you refit and time them yourself however? Yes, you can run them on a standard ECU. However, with a new ECU and better injectors, it will make similar power to Graham's engine on a standard inlet manifold, ie around 110kW at the wheels. Tweaking Graham's engine could net 120-125 kW at the wheels.

At 160hp, the 8V is starting become a grumpy animal, with a noticeably rough idle. It's easy enough to extract 220+ hp with an 8V turbo, if you like all the pipe work.
 
To underline Peter's comment about getting circa 110kW with mild tweaking of a J4RS, PatPug's car made 108.8kW at the wheels with a J4RS with Peter's stage 1 cams and a Haltec and nothing else. At that power it was at the limit of what the standard injectors could deliver. With the same base motor and same cams but a better ECU, bigger injectors, higher comp pistons, 11.5 static CR, forged internals, some more work on the head etc, my car made 110.6kW Retuned with stage 2 cams my car made 110.7kW at peak revs, but less torque everywhere else so I stayed with stage 1 cams for the better mid-range and almost identical top end.

Pat's car and mine were tuned on different dynos on different days, so you can't really compare the measurements, but we ran both cars doing 3rd gear roll outs side by side on a freeway and they stayed neck and neck from about 70km/h until well illegal speeds. Pat's car had a 4.06 final drive and mine is 3.9 so that suggests mine was matching Pat's power at slightly lower revs all the way through the range, plus Pat had stripped a bit of weight out of his car compared to mine. To me, that says that mine does indeed make just a bit more power at any given revs than Pat's, but not much difference for a huge amount more money spent. Others may correct me, but what I took out of that was unless you are going ITBs, don't bother with other work on a J4RS.
 
Just to look at this from different angle: I go to sell the car one day (no plan to do that but who knows) and what am I offering as a sales pitch? The later, known engine is probably more convincing ie "it is a GTi6 205" I get it.

Peter, I need to hand the car over to a mechanic here and they would help sort out your re-ground cams. Is reinstallation and tuning a long job?

Just to get the gearbox straight for a GTi6- I can use my BE3 with quaife and Im done? If I need to modify it, what do I ask for? Send it to Adrian?
 
Ash,

I can help you install the cams if you go the gti6 route. I’ve recently done it to mine with great success (thanks Peter T!)

You’re BE3 will bolt right on, it’s just a question of ratios and how quick you want to get the car on the road. Quaife is a smart idea too.
 
Thanks Rich, great offer. It does not sound like a difficult task with such help. I think we have at least 3-4 great example cars of what to do here.
 
You also need to find and fit a lower ratio final drive.
 
Its good measure to have the BE3 refreshed if not already by Adrian. Hes know how to get them just right and will tighten it up so to speak. Lower FD as mentioned by rich. Or just use a VTS box.

Cams are not a big deal to tune. If you have a Haltech on it there is a few base maps to get u going then a final dyno tune when its on the road.
 
cam85 said:
Its good measure to have the BE3 refreshed if not already by Adrian. Hes know how to get them just right and will tighten it up so to speak. Lower FD as mentioned by rich. Or just use a VTS box.

Cams are not a big deal to tune. If you have a Haltech on it there is a few base maps to get u going then a final dyno tune when its on the road.
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VTS box has nearly exactly the same ratios as Mi16, may be a BE4 though?
I have not had any trouble with MS3 on 60-2 triggering until this car! It needs the battery to be right up when starting from cold then OK. I am going to change to Hall Effect , if this doesn't fix it then it won't be going with the engine.
 
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I run hall effect 60-2, in the normal hole. It works a treat.

Pat's car with it's 4.06 cwp and GTi gearset, is the ultimate combination. However, if you're heading to the track you need the 4.43 cwp.
 
PeterT said:
I run hall effect 60-2, in the normal hole. It works a treat.

Pat's car with it's 4.06 cwp and GTi gearset, is the ultimate combination. However, if you're heading to the track you need the 4.43 cwp.
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I run 4.8 in my rally 309. Combination of that, GTi6 inlet manifold,10.4 to 1 pistons, standard cams and Megasquirt 3 is spot on, which is why I have no need for the XU10 engine.
 
Scroll down from there you can see my 205. This is a stock 205 Si.
 
GRAHAM WALLIS said:
Really you don't need all this work anyway just go and have some fun. The 405 is a stock DFW probably untouched since new and done 6 years of motorsport.https://www.facebook.com/raymond.ga...ehOAOdavEzkt5j6HwO8eWa6rYUGERLvOxpYPuu4yq1XPD
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There definitely is some merit in having a simple plan and getting out and enjoying it. Too many projects only live in the shed. I had a 68 Fairmont some time ago that had big go fast plans, due to work relocation I had to simplify them and reassemble really fast, like 4 weeks... I ended up with less power but 12 years of driving enjoyment. I'm sure Ash you can get a 16V up and running with minimal fuss, I'm looking forward to watching the fasttrackS3205GTI16V project build.

Maybe there should be a thread/post on how to do a simple, minimal fuss 16V conversion
 
Craig, I was thinking that few people would be looking into 16V conversions anymore because A, there are so few cars left or for sale and B, more value in an original car. It only because this green car has a weld in cage and a history of track work that makes it a candidate for me.
As an update, I am looking into buying a local Gti6 engine or possibly Grahams combination if he can make it work.
 
Definitely Ash your car is a perfect candidate for this, not mucking around and just getting it done, I was preaching to the converted so to speak. I'm sure you can navigate all this and get your 16V conversion done with little fuss.
 
Does the $4K for Graham include gearbox as well? If so, I'd buy it if I were you, before I do.
 
It gets real tight with the cast iron block if you want air conditioning, let alone the inlet and the condenser. The alloy is another matter I hope!
 
Matthew said:
It gets real tight with the cast iron block if you want air conditioning, let alone the inlet and the condenser. The alloy is another matter I hope!
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Hope you don't mine me coming in on this..

I have the S16 motor with quads TB in my gti with Air and all fits up well.
By the way my first tune give me 120KW at the wheels with 265FtLb torque.
 
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