[car_overhaul] Project Jalopy

[harryskid 193]

a 205 one will work and can be clipped away from the manifold, but I think I';d me bore comfortable using a longer one and routing it a little higher up the bulkhead.

 

Mine works ok like that but than its not used every day !

[maxi 36 1 Cars]

Seems a REAL shame...... If you are around sussex at the weekend, bring a manifold with you and I will modify it for you while you wait. I was re-angling them years ago and have done many for myself and others.

 

Just an offer, seems a shame to have to back track.

 

Maxi

[Anthony 1,000]

Thanks for the offer Adam, but I now finally have the re-angled manifold in my greasy mitts - thanks Alastair for dropping it off earlier this week

 

It was a little frustrating having to back-track slightly, but most of the prep work is now done so it should be a quick and easy conversion next year.

[Anthony 1,000]

The SBC 1.9 8v engine is now fitted and running

 

 

There's a few things that need doing - tracking, re-bleeding the brakes and sorting a few minor electrical gremlins - but for the most part it seems to be OK and certainly starts, runs and drives again for the first time since it was MOT'd back in the summer.

 

Good news is that the gearbox appears to be fine now after Miles replaced the reverse gear parts and gave it a once over, and looks like my suspicions on the oil pressure sender being faulty were well placed - with the replacement sender and the loom having had a once over, it now reads over 6 bar cold oil pressure and a little under 5 bar hot, which is much better than the 3.8 bar that it had topped out at previously!

 

Weather and time permitting tomorrow, I'll get the remaining bits done and drive the old girl in anger.

[feb 47]

That's good news Anthony, well done!

[jon.ford 3]

What a great read that article was well done. I enjoy driving my 8 valve car as much if not more than my mi16 car

Interesting to see what you do next. Best of luck Jon ford

[welshpug 1,626]

shame its still on Jetronic

[Anthony 1,000]

shame its still on Jetronic

It's a temporary engine, so doesn't warrant the time/cost of something aftermarket, and I doubt it'll run ideally on either of the MP3.1 setups that I've got (either with the 405 SRi ECU from a XU9J2 engine, or a ZX Volcane 1.9i ECU from a XU9JA/K engine).

 

Besides, properly set up, Jetronic works surprisingly well - indeed, I was surprised at just how small the gains were from aftermarket when I got my other one mapped for Fivos - driveability improved no doubt, but in terms of actual figures, there was very little in it and on the road at least, the Jetronic AFR's were pretty much spot-on.

 

Too many people assume that a car that barely idles, gives poor fuel economy and is awful to drive is how all Jetronic setups are. They're not.

[welshpug 1,626]

indeed I agree completely

[Anthony 1,000]

Not updated this in a while, but the car has been on the road for a few weeks now.

 

I've only done 500 miles or so in it so far, but generally I'm very happy with it and does exactly what I set out to do in that it's taken what makes a 205 GTi great and improved upon it, without compromising it as a road car or losing sight of the qualities that makes a standard car so enjoyable.

 

It's perfectly suited to be a daily driver in that it's quiet, comfortable and still compartively softly sprung/damped, but come to some twisty bits and want to have some fun, and it displays balance, poise and turn-in and you can't help but smile. It's not the quickest thing in the world (more on this in a minute) but it's quick enough to entertain and what power it does have is easily accessible and the gear ratios are well matched.

 

The Xsara VTS rack is wonderful too. It's perhaps a little over-assisted (I've kept the PAS) but the quickness transforms the feel of the car in a way that's hard to describe without driving it - what I will say though is the standard non-PAS rack on the 205 Mi16 I picked up earlier this month makes it feel like driving a Routefinder bus by comparison by how slow-witted it feels.

 

I'm really happy with it and it's been worth the countless hours labour I've put in so far

[Anthony 1,000]

Thursday night I was over helping Justin (Kyepan) get to the bottom of the fuelling issue on his 205 Mi16 on the rolling road, and while there it seemed rude not to stick my car on and see just what the engine was producing.

 

I've always said that the figures quoted by Skip Brown are nonsense frankly and in the rhelms of fantasy - the actual engine that I've got is the one in the article on the main 205GTiDrivers website which was claimed to be 141hp @ wheels, which is more than I'd expect from a lightly breathed on Mi16 or GTi-6, let alone an 8v on standard management. At the flywheel I could have expected that figure, and that would have tied in with some rolling road tests that Feb (who bought the car from Andrew) had done a few years ago.

 

 

Today however, 11 years and 60k miles odd later, it's clear that some of the horses have bolted and as a result it made just 125hp @ flywheel - surprising, and if I'm honest, a bit disappointing.

 

It isn't immediately clear why it is down on power either - it still has a healty 190psi+ on all four cylinders, pretty much everything ignition wise is new, the fuelling looks sensible (perhaps a touch rich, but not terribly so) and the dizzy is the same one from Feb's current engine (previously Daz-C's) which wasn't far off the power it made when mapped on Emerald. Only thing I can immediately think of is the cam timing, as I know that has been set in a different position between this and Feb/Daz-C's engine despite them being the same spec and having the same RS3 camshaft fitted, and would make sense given that the engine is producing peak power 300-400rpm earlier than I would expect it to like the camshaft is over-advanced.

 

Still, I've always said that peak power figures aren't everything and so proves to be the case here, as on the road it certainly punches harder than that 125hp would suggest - Justin had been slightly taken back as to why he'd been struggling to pull away from me on the run down to the rolling road and was probably just as shocked as me when it turned out how little it was making comparitively - his car was 45hp up on mine!

 

The reason it performs well on the road I suspect is the torque curve and resulting powerband - it's almost like a modern low-boost turbo engine in that it has a near flat torque curve and by my reckoning, is producing 90% of peak torque from about 2200 through to 6100rpm and thus doesn't need to be kept on the boil. Power doesn't really fall off at top end either, as despite peaking at 125hp @ 5700rpm, it's only 4hp down when it hits the 6500rpm limiter.

 

Basically, the headline figures are rubbish, but the delivery and flexibility is spot-on.

 

The excitement of being the center of attention did get too much for the old girl though and she promptly (and rather embarassingly) wet herself with what looks like a failed thermostat housing gasket or possibly thermostat seal - basically there's a fair amount of coolant on top of the gearbox and underneath the thermostat housing, but the coolant hose connections were all fine and dry, as was everything in front of the gearbox and the front of the engine.

 

Ah well, it's an 8v - it doesn't need coolant anyway, especially with a lack of horses to cool down

[Paul_13 212 1 Cars]

Glad you got home

 

Did keep up well with Justin's MI, good midrange grunt

[sensualt101 31 1 Cars]

i am glad its on the road and all legal now and being used! you have saved a great car mate! i too have a 92 1.6 gti and reading your thread will i am sure come in useful to me so thanks!

[Sandy 189]

Don't be too dispondant (sp?), Dyno Dynamics rollers are not the paragons of "accuracy" they're often portrayed as, they often spit out inexplicably low results among seemingly reasonable ones. It is a rolling road at the end of the day and vulnerable to the variations and calculations involved, don't read too much into it.

[Bas 6 1 Cars]

The excitement of being the center of attention did get too much for the old girl though and she promptly (and rather embarassingly) wet herself

 

 

:lol: :lol:

[maxi 36 1 Cars]

Don't be too dispondant (sp?), Dyno Dynamics rollers are not the paragons of "accuracy" they're often portrayed as, they often spit out inexplicably low results among seemingly reasonable ones. It is a rolling road at the end of the day and vulnerable to the variations and calculations involved, don't read too much into it.

 

 

Im not being awkward and trying to inspire an argument but I dont agree with this. Dyno Dynamics are renoun throughout the rolling road/diagnostics industry (of which I have spoken to and know many people within) as being more realistic. No rolling road is truly acurate, engine dynos are basically the best way to get a measured figure of the said engine on a test bed - thats not to say that same engine will make the same figures within its engine bay envirolment- but all over the world dyno dynamics setups on the whole give realistic figures, shooting down pub BHP.

 

Please dont for one second think I am attacking you here sandy or saying any of your results are pub BHP as everyone in the community has the upmost respect for your work and knows you get fantastic results, I just dont personally agree with what you have written there.

 

Maxi

Edited January 30, 2012 by maxi

[Sandy 189]

I half expected you to respond to that TBH, knowing you've said similar things before and I was careful how I phrased it, because I wanted it to be informative and not deliberately provocative. Any engine I really want to get accurate figures on, or develop constructively, I dyno, because rolling roads simply aren't accurate or repeatable enough, people who accurately dyno engines regularly know this. People who spend tens of thousands on a new rolling road, usually on credit and need it to be working every day to pay for itself, are often rather less keen to face that fact. Pretty much every rolling road operator/owner will tell you his system is near perfect, the Dyno Dynamics marketing has been exemplary, as has Superflow and both are respected in the industry, but the same cars more often than not show different results at each with no other major factors involved... how can that be if they're both right?

If like me, you've cut your teeth on an old basic rolling road, and it's the same machine for most people (Sun RAM XII), and it's well calibrated, you'd have seen a pretty repeatable set of figures for similar cars, lets take an example... a cammed/TB'd/high comp well set up Saxo VTS, showing around 150bhp at the wheels in 4th, in most peoples money, probably 175bhp flywheel, a notably brisk example and then it goes to a DD rolling road day, still running perfectly soon after mapping, a couple regular cars, like a GTI6 at circa book power run, then the Saxo shows 148bhp flywheel. That was my first experience of DD rolling roads and since then there have been many more occasions, such as one of my pal's 2 litres, which we dyno'd at just over 290bhp, with the right exhaust etc, goes to a DD rolling road and shows just over 250bhp, customer furious etc. Goes to another RR for a second opinion and shows 296bhp and with no changes is now one of the top 2 litre rally cars in Ireland, customer bewildered but happy. I have many more tales like this, the only pattern is that the results seem very inconsistent and tend to be inexplicably low, rather than high as I mentioned. I'm happy to listen to secondhand stories, but these are my personal experiences and very frustrating they are too. That's why I made the point.

[Miles 331 1 Cars]

I remember years ago maybe at PTS in Luton where the PSC had a RR day, I'm sure Feb's can then was reading low then and I'm with you that getting that power on std injection isn't that realistic

[Baz 421]

Perhaps rolling roads get more accurate as they get older. That's the only justifiable explanation here.

[maxi 36 1 Cars]

Fair points above ^

 

All I can say is......get that valver in there Ant!

 

Maxi

[Anthony 1,000]

After its spot of incontinence at the rollers, I whipped the thermostat housing off that weekend.

 

 

Neither the housing gasket or the thermostat rubber seal appeared to have obviously failed, but with the seal replaced and the remains of the old gasket removed and RTV sealant used instead, it seems to be water tight again so I'll see how it goes.

 

Annoyingly, the clutch judders and snatches since the leak so I'm guessing that a fair bit of coolant went into the bellhousing and contaiminated the clutch given that it was fine previously. With any luck it'll burn off in a few miles, as I really don't want to have to pull the gearbox off.

 

 

Also, took the opportunity to fit the strut brace that I had left over from my previous 205, but having subsequently discovered that the bonnet no longer closes properly (it does close, but it bows slightly in the middle where it's sat against the strut brace) it'll be coming off again after I've driven the car in anger to see if it actually makes any difference. If it does, I'll find another design that fits my car better, and if it doesn't, well then there's no loss.

[Anthony 1,000]

With the weather having turned distinctly wintery, attention turned back to the forthcoming GTi-6 engine installation and the bits that I could do in the comfort of the living room.

 

First up was the inlet manifold, and getting rid of the resonator box. My main reason for doing so is quite simple, and that's that with the box removed it makes working on the engine that bit easier and means that I can get to fixings and connections around the front of the engine without having to remove the inlet manifold by squeezing my hand between the inlet runners.

 

Can't hurt from a reliability point of view either, as whilst not common, it's far from unheard of for the plastic resonator box to crack or even have large holes blown in it should the engine backfire for any reason - in both cases, the resulting airleak causes major running issues.

 

 

Some people have sealed the hole left by removing the resonator using the cap from a milk carton siliconed in place, and while admittedly it does seem to work fine, I wanted something a little more substantial made for the job.

 

Thankfully, Tom (Cheesegrater) had spun a few up on the lathe and I took one off his hands in exchange for some ale of his choosing.

 

 

Using the seal removed from the old resonator, it was a very snug fit and isn't likely to come out anytime soon, although I might make a little retaining bracket just to make sure it can't work its way loose over time.

[Anthony 1,000]

Next up was the exhaust manifold that I had received back from getting re-angled by Alastairh.

 

Welding all looked to be well done and I know that there's a few of Ali's manifolds out there in use so I'm confident that both the quality of the work and the amount it has been re-angled by should be spot on.

 

 

One thing that crops up again and again whenever you read other peoples GTi-6 conversion threads is problems with heat from the exhaust manifold causing issues everything in the immediate vicinity, with things like melted grommets being common, and rather more concerningly, coolant and fuel pipe failures. I've actually been at the rolling road helping to map a friends car when a coolant pipe burst and exploded in a cloud of steam and scalding hot coolant, scaring me half to death.

 

Most people seem to try to address the heat problem by covering everything with heat reflective covering, which while it works to a point, it is in my eyes merely dealing with the symptoms rather than the underlying cause - namely the exhaust manifold itself. Sort that, and there won't be the excess heat to have deal with, and should help keep under bonnet temperatures as a whole to more sensible levels - or as sensible as you're going to get with a large engine crammed in a small engine bay anyway.

 

I decided that the best solution was to heat wrap the exhaust manifold, keeping the heat out of the engine bay and away from the parts in close proximity that are liable to be damaged. I'm sure this route will certainly polarise opinion and it's certainly not without it's potential downsides, but to me it seems to be the easiest and most cost effective way of addressing the heat problem.

 

The GTi-6 manifolds are cheap enough to be pretty much consumable, so I'm not too fussed if the manifold ends up scrap after a few years use with the accelerated corrosion/fatigue that heat wrapping can cause - indeed, given my previous track record with 16 valve 205's if the engine survives long enough for the manifold to fail I'll be amazed I'm not even convinced that it will be much of an issue anyway, especially as I believe that GTi-6 manifolds are stainless as standard and thus much more resistant to corrosion that mild steel would be.

 

I'm certainly not expecting any of the claimed performance increase - this is solely an exercise in heat control.

 

What I will say first and foremost is that the warnings about wearing gloves when you apply the heat wrap are there for a reason - don't do what I did and ignore them, as the resulting itchiness is terrible. You have been warned!

 

Secondly, you will need far more wrap that you initially think you'll possibly need - I bought 20m of 2" wide wrap, and I've only got about 3m remaining after finishing the manifold! To break that down, on the four individual pipes I used 3.5m on cylinder 1 (flywheel end), 4m on each of the middle cylinders 2 and 3, 3m on cylinder 4 (cambelt end), and around 2.5m wrapping the collector.

 

The way I did it was to cut the wrap to length and soak it in a bowl of water, which allows it to stretch slightly and then contract as it dries, gripping tightly to the manifold. After cleaning/degreasing the manifold, I started at the collector end, wrapping around a couple of times before securing it with a metal clip, and then proceeded to wrap tightly down the pipe overlapping by around 50% as I went and wrapping around a couple of times at the end and again, securing with a metal clip. That sounds easy, but it's somewhat awkward on the centre two cylinders in particular, with the tight radius bends and close proximity of the pipes to each other. I suspect that 1" wide wrap would be much easier here, but the 2" worked well enough.

 

The reason I started at the collector end was to ensure that the wrap overlaps faced in the direction of airflow, which should mean that the air flows over the wrap, rather than trying to get underneath the overlap and speeding up the wrap starting to fray and look tatty. Should also mean that any fluid leaks shouldn't get between the layers of wrap as easily, which is no bad thing as oil or brake fluid soaked wrap can be quite flammable.

 

With the four individual pipes done, I then wrapped the collector part, again starting furthest away from the engine and working backwards to ensure that the overlaps faced the right direction, and secured both ends with a metal clip to prevent it unravelling.

 

 

I'm quite happy with the end result for a first attempt! I might put a few more clips on though before fitting.

 

The only thing I'm undecided is whether or not to coat the wrap with anything once it's finished drying. There seems to be three schools of thought on this:

1. Leave the wrap as-is and don't coat it with anything
   
2. Use a high temperature silicon based spray to seal and weatherproof the wrap
   
3. Spray the wrap using VHT paint to seal the wrap and help prevent it from fraying
   

Any comments or experiences with the above three opinions would be much appreciated.

 

I'm debating whether to use the remaining 3m of wrap to do the top part of the exhaust downpipe, but at the moment I'm erring on the side of not doing so - firstly, the downpipe is only mild steel, and secondly, the downpipe is much more exposed and liable to get wet from road spray and splatted with any leaks from the sump or O/S driveshaft oil seal. Some also suggest that the heat differential in a part-wrapped pipe isn't a good thing for longevity, although how much truth there is in that I don't know.

[Anthony 1,000]

Oh, and one more thing for those interested - here's a side by side of the re-angled manifold against a standard one to give you an idea of the difference

 

[kyepan 291]

very nice, as i said last night..

 

ps

 

I have a theory that you're actually tyler durdon from 'Fight Club' you don't sleep!!!