Mi16 Myths - Let's Get This Sorted!

[Dino 3]

My Mi16 has 181bhp and the main mods are VAG TB, Piper 270s and some mild porting. The engine is lightened and balanced but I doubt that gives any real difference to power figures (?)

 

So I have gained 21bhp over standard but as said before just a pair of cams will cost you enough!!

 

As previously mentioned perhaps an inlet cam is the way to go. Even (!) a 170bhp 205 feels like a monster, heck a standard one is bloody quick enough!

[petert 550]

People often loose sight of the fact that an Mi16 head flows well enough out of the box to make 250hp. You just need to add the right components around it. There's no such thing as a cheap 225hp, but this is what I'd do for a budget build:

 

- fit 0.5mm copper head geasket (increases CR to 11.25:1 and decreases squish height)

- buy ONE new solid intake cam

- regrind the exhaust cam to a solid grind, smaller than the intake.

- reco. the std. head and fit solid lifters

- add TB's, individual coils, ECU etc.

 

Naturally you'll need to cut the valve pockets deeper as you'll need a reasonably big solid cam to make hp @ 8000rpm. You'll never make that sort of power with hydraulic cams. Of course that all assumes you'll find a good bottom end with liners that aren't excessively worn!

[DrSarty 90 1 Cars]

I hope my lack of genuine knowledge but the desire to learn has posed the right question here. It's abundantly clear that there is some good advice here. I thoroughly agree with the comment that standard on it's own is something special, and that any expensive mods are really destined for a serious competition car which simply wouldn't be practical on the road.

 

I only remembered this morning that the standard ECU isn't mappable, so well picked up, and £500 is a lot of dosh unless you're either loaded or going for serious competition.

 

So without going what could be called the balls out, professional route i.e. going the mappable route, does it seem that an uprated inlet cam on a cleaned and tidied head, with perhaps this 0.5mm coppper gasket and a decent exhaust is the (dare I say it) cheapest/quickest way to get a noticable tune for the Mi.

 

And just before I stop, estimating that the above would cost...hmm..£750, would R1 bike carbs plus of course their bespoke inlet manifold (I guess at around £400 all in) be a mod which if included would make any impact at all without going down the pro route i.e. does the carbs/TB route send you down the pro (read expensive and serious) road?

 

Dunno if I worded the last bit right, in other words, is the border crossing between simple fast road (cheapish, can be done with engine in car) and proper track/competetive car rest squarely with carbs/TBs. I say this because I've gathered from the replies that to capitalise on the flexibility of control of fuel and air from using TBs etc that you enter a whole new arena where a mappable ECU and all the associated set up costs are a must?

 

Dr S

[Robsbc 0 1 Cars]

Also on Emerald's rollers as Kate's my own Mi16 acheived

 

212 BHP @ 7124rpm & 162lbft @ 5878

 

Full spec can be found here with graph : http://forum.205gtidrivers.com/index.php?s...c=52847&hl=

 

Revla a friend of mine fitted a pair of cat cams, tb's to a 2.0S16 and achieved 202BHP (7200rpm) & 158lbft (5900rpm) on Emerald's rollers. The difference is I'm about 30lbft higher in torque around 3000rpm.

 

Revla's results are here on page 2 http://forum.205gtidrivers.com/index.php?s...53718&st=30

 

Rob

Edited September 22, 2006 by Robsbc

[16v205 9]

May aswell add my rolling road graph mapped at emerald aswell. 211bhp & 161 lbft with a fair bit more torque through the mid range than a standard mi16.

 

 

Engine spec was:

 

Standard Gti-6 Engine

Catcams 4903108 Camshafts

Catcams retainers and springs

Jenvey 45mm throttle bodies and 90mm trumpets

Emerald ecu

 

Rich

[DrSarty 90 1 Cars]

This is all LOVELY stuff! It seems then that around £1200 or so can net you a very useable 30bhp with accompanying torque increase in a road usable range no????

 

Dr S

[huckleberry 0]

When I read your initial question you were talking 300 pounds and now you are 1.200 pounds which is 4 times as much.

 

I haven't got a tuned MI16 myself but from all I've read here it's not at all easy or cheap to get 200 bhp out of a mi16 engine. Cams, TBs (or carbs) and management should see good gains, but that's already a lot of money. If the catcam inletcam would see already 17 or 20 bhp then the extra 13 - 16 bhp (if we take Kate's 193 bhp as a goal) are very expensive in my eyes as you would need management and TBs to get there. You were also talking about a BV head. Those are very expensive. I you WANT the 225 BHP you could go all the way and spend a lot of money, but you might want to make yourself a list of gains compared to expenses. Maybe you'll lower your goal after that, maybe you don't.

 

From all I've read here around 180 bhp is doable for a reasonable amount, 200 bhp is getting quite expensive and 225+ is only fun when you have a lot of money and a good engine builder.

 

Hope you can use this info. I've bought myself a GTI6 engine, but I'd go MI16 I'd only get the catcam, and management.

 

Tim

Edited September 22, 2006 by huckleberry

[Dream Weaver 2]

It always costs a hell of a lot more than you figure and I would concentrate on the basics first.

 

I bought my 205 with std Mi16 engine back in 2003. Engine burned oil like a bastard and subsequently stopped working so I stripped it out to fit a new engine.

 

The original rolling road showed:

 

166bhp at 6,600rpm

132 ft/lbs at 5,960rpm

 

...on the old std engine with just a K&N filter.

 

Since then i've spent a lot of time and money, circa £2,500 on a rebuilt engine, Emerald ECU/loom, bike bodies (lots of time to build these as well), engine has Piper 270 cam and head work.

 

The result after that was:

 

173bhp at 7,500rpm

127 ft/lbs at 6,500rpm

 

Before/after were different engines and different rolling roads though.

 

thus no torque and not much drivability, so it cost me £2,500 to gain 7bhp and lose some torque and the car doesn't drive as well as it did before, in fact its boring.

 

Now it may be the bike bodies setup, exhaust, mapping or any other factor that's holding it back, I don't know - but i'm going to have to keep spending on it to find out with the first job being to try a different induction setup - each change will need another mapping session at circa £200-300.

[TEKNOPUG 3]

Mi16 N/A's

 

[DrSarty 90 1 Cars]

Thanks tekno.

 

Tim, you're right. I'm not a numptie with more money than sense and by being taken in by wild figures of BHP, which we all (including me) know is NOT a sign of usability of a car, especially as a normal road car, then my initial plans/expectations whatever you want to call them were to a degree a sign of immaturity, lack of decent knowledge and gullibility. As for the £300 thing, that was me being taken in by hearsay that EITHER the BV head OR the bike carb set up would net you 20-30bhp. I've since learned that that is likely not the case, either by it not being a high enough cash outlay for the items and/or that more in depth work (aka the mappable ECU and RR sessions) is required to realise the desired gains.

 

However, this thread with nearly 600 views in half a day show it's a subject close to many engine tuning and driving fans' hearts.

 

What I hoped to establish was what can any owner of a standard Mi engine hope to achieve by a financial input of A and effort input of B, taking into account MY goal of a thoroughly usable but better performing Mi 205 road car.

 

My conclusion thus far is, based on a MUCH more realistic situation of a usable car with better torque (grunt)just happening to have 180bhp, then the most cost and labour effective way of achieving it is:

 

* head off and cleaned/flowed with catcam inlet shaft fitted

* solid lifters & exhaust cam ground/reprofile as per earlier post (by petert I believe)

* 0.5mm copper gasket used on head refit (as above) & together with

* 4-2-1 exhaust manifold fitted at head refit too.

 

It would seem that this combination offers a performance (road suitable!!) gain of around the 20bhp mark. This is perhaps conservative if the catcam inlet really can produce the results as hinted at back at the start.

So what's the cost of this? If catcam's around £230 - basically flowed head £300 (is BV achievable at a similar price?) - gasket £50 (?no idea) - manifold £300 - lifters & head ancilliaries - £100 (?again no idea), then you arrive at my £1000 guestimate.

 

Now IF my summary is relatively logical, would someone help fine tune it, perhaps I've missed something e.g V pullies and tidy up my price guessing. Somehow I think it'll return to the £1200 mark which proves that my initial impression via misguidance of 20-30bhp from a £300 investment was total w%nk - again proving that you should really speak to the experts and not get carried away with some bhp figure crusade

 

Everyone worn out yet or what???

 

Dr S (and a bonus for tekno)

[sorr 0]

Right my input. I have just about completed a full Mi rebuild including an inlet only cam and now wish I had gone a different route. I got a turbo charged car as a subsitute as the 205 was moved to weekend play thing.

 

I wish that I had built and 8v turbo. While this would not be too high in the HP department it would have monster torque. I actually think it ismore important to concentrate on the torque than the HP for a road car. A turbo 8v will be great on the road, really placid around town then up the rev range to get the bost and the fun will begin. Also given a turbo will not need to be reved hard you should, assuming you deal with induction cooling and increased underbonnet temperatures appropriately, get longevity.

 

It is also worth remembering that the 205 is a very light car and does not need much power to be fun.

 

On the finance side, as I am sure dreamweaver would agree, it is damned expensive to rebuild an Mi and in my opinion tuning an engine that has not been rebuilt is asking for trouble. On this point it may not be worth going Mi and use a GTi6 engine, more power and torque out of the box and less likely to need a rebuild.

[huckleberry 0]

basically flowed head £300 (is BV achievable at a similar price?)

 

I thought you said you read the Pumaracing page. A BV mi16 head is over double, maybe even triple that. And then it is in a box under your bed. You might want to freshen up the engine too and need parts to fit the head. You're going to have a heart attack once you've seen all you've spend when it's done

Edited September 22, 2006 by huckleberry

[DrSarty 90 1 Cars]

Thanks Sorr, but I don't have a turbo charged engine, I have an Mi. The whole thread is about an Mi and I'm not about to wang the lump out I've just shoe horned in.

 

Given a different start point it would have course gone a different route. But your point about not trying to tune an engine which hasn't been looked at and most likely rebuilt from the ground up (aka making sure the foundations are secure before building) was TOTALLY valid.

 

Dr S

[DrSarty 90 1 Cars]

I thought you said you read the Pumaracing page. A BV mi16 head is over double, maybe even triple that.

 

Thanks Huck, I was going from (an obviously misfiring) memory re the cost of BV, hence I questionned it. But as for a gas flow, port and polish, is £300 a realistic figure please??

[Dream Weaver 2]

I wish that I had built and 8v turbo. While this would not be too high in the HP department it would have monster torque. I actually think it ismore important to concentrate on the torque than the HP for a road car. A turbo 8v will be great on the road, really placid around town then up the rev range to get the bost and the fun will begin. Also given a turbo will not need to be reved hard you should, assuming you deal with induction cooling and increased underbonnet temperatures appropriately, get longevity.

 

I have that regret many times, a turbo 8v would've been much nicer for me

 

Though i'll have to see what I think when i've done a gearbox swap, and sorted the exhaust and induction.

[smckeown 1]

I have that regret many times, a turbo 8v would've been much nicer for me

 

Though i'll have to see what I think when i've done a gearbox swap, and sorted the exhaust and induction.

 

I reckon you will change your mind once you have the box swapped. An mi on a good box is extremely good even with a plenium, on TBs it's going to be a screamer I think a turbo will be like chalk and cheese in comparison

[DrSarty 90 1 Cars]

I feel for you DreamWeaver - must be gutting - respek for effort. I bet you're

[Alan_M 66 1 Cars]

I reckon you will change your mind once you have the box swapped. An mi on a good box is extremely good even with a plenium, on TBs it's going to be a screamer I think a turbo will be like chalk and cheese in comparison

 

Too true, 1.6 box all the way.

 

To be honest, even a mildly tweaked 205 Mi with a 1.6 box will be fairly rapid.

 

Do you have a budget to work to?

[Dream Weaver 2]

I feel for you DreamWeaver - must be gutting - respek for effort. I bet you're

 

Thanks, I'm not too worried, it's been really good fun doing the project and just needs the niggles ironing out. It should be a decent car when i've got it where I want it

[boombang 2]

I don't get the obsession with headwork?

 

Peter has mentioned the Mi16 head flows fine out of the box, and also read this here too http://www.guy-croft.com/viewtopic.php?t=1...333cb4ee00dcddc

 

Halfway down he says this "Before and after. The compounded gain is huge. Not impressed? The standard head flowed so much, I first wondered if I'd find much gain at all.."

 

Yes he got a gain in flow, but as said it flows so well as standard!

 

Maybe a tidy up is worthwhile but save the headwork money and spend it other things is my opinion.

[James_R 3]

Power doesn't make for a fast car. which everyone forgets.

 

I'd rather go for a std powered Mi with kit on to stop surge, slicks, 40% diff, 1.6 box and a qwikrack.

 

that will make for a very fast 205 compared to a 220BHP Mi 205 with otherwise standard running gear, on track of course, down the local duel carrageway is another matter altogether.

 

my next engine is a GTi-6 based unit, but I'm just lookign for surge free track abuse and no power increase, Anthony and other will tell you how fast a std Mi can go on track.

[maxi 36 1 Cars]

http://forum.205gtidrivers.com/index.php?s...c=60063&hl=

 

Heres the topic from when mine was mapped. It leaves lines of rubber as it comes on cam in 2nd gear and will spin through 3rd too. Lots of hard work put into it and makes me smile everytime I drive it. NEVER had anything come past it. Blew the gearbox to pieces last weekend so im trying to source another unit at the mo.

 

Maxi

[jackherer 543]

Blew the gearbox to pieces last weekend so im trying to source another unit at the mo.

 

which gear ratios were you running out of interest?

[maxi 36 1 Cars]

which gear ratios were you running out of interest?

 

Std mi box boss.........might go to a 1600 unit....

 

Maxi

[Mattsav 1]

Thanks tekno.

 

Tim, you're right. I'm not a numptie with more money than sense and by being taken in by wild figures of BHP, which we all (including me) know is NOT a sign of usability of a car, especially as a normal road car, then my initial plans/expectations whatever you want to call them were to a degree a sign of immaturity, lack of decent knowledge and gullibility. As for the £300 thing, that was me being taken in by hearsay that EITHER the BV head OR the bike carb set up would net you 20-30bhp. I've since learned that that is likely not the case, either by it not being a high enough cash outlay for the items and/or that more in depth work (aka the mappable ECU and RR sessions) is required to realise the desired gains.

 

However, this thread with nearly 600 views in half a day show it's a subject close to many engine tuning and driving fans' hearts.

 

What I hoped to establish was what can any owner of a standard Mi engine hope to achieve by a financial input of A and effort input of B, taking into account MY goal of a thoroughly usable but better performing Mi 205 road car.

 

My conclusion thus far is, based on a MUCH more realistic situation of a usable car with better torque (grunt)just happening to have 180bhp, then the most cost and labour effective way of achieving it is:

 

* head off and cleaned/flowed with catcam inlet shaft fitted

* solid lifters & exhaust cam ground/reprofile as per earlier post (by petert I believe)

* 0.5mm copper gasket used on head refit (as above) & together with

* 4-2-1 exhaust manifold fitted at head refit too.

 

It would seem that this combination offers a performance (road suitable!!) gain of around the 20bhp mark. This is perhaps conservative if the catcam inlet really can produce the results as hinted at back at the start.

So what's the cost of this? If catcam's around £230 - basically flowed head £300 (is BV achievable at a similar price?) - gasket £50 (?no idea) - manifold £300 - lifters & head ancilliaries - £100 (?again no idea), then you arrive at my £1000 guestimate.

 

Now IF my summary is relatively logical, would someone help fine tune it, perhaps I've missed something e.g V pullies and tidy up my price guessing. Somehow I think it'll return to the £1200 mark which proves that my initial impression via misguidance of 20-30bhp from a £300 investment was total w%nk - again proving that you should really speak to the experts and not get carried away with some bhp figure crusade

 

Everyone worn out yet or what???

 

Dr S (and a bonus for tekno)

 

For 180bhp you dont need solid lifters (and you wont get a set for #100 Either, oh sod it a new laptop and still no pound sign!!!!)

 

#300 of headwork will probably lose you flow, not gain it (trust me, I've flow tested a lot of other people's Mi16 heads and they range from a couple of percent gain to a massive loss)

 

Whatever you do the basics must include:

 

Big ends

Mains

Thrusts

Rings

Upper & Lower Gasket sets

Cambelt Kit

Water Pump

 

Then when you've got a solid engine you can start adding parts to make it go faster.

 

If not you'll blow it up very quickly and end up spending more in the long run.

 

With the 1.9l engines 175bhp is cheap. Anything more and the costs start soaring up.

 

Personally I'd go for the big capacity Iron block option for road car.

 

216bhp and 174lbft of torque without spending a fortune ( although a lot more than the #1200 budget)

Not the nicest torque spread but in a 205 your not too bothered what happens at 3000rpm, just drop a gear and go.

 

For a 205 I think N/A is the way to go. The handling is what makes them so special so why go and ruin it with turbo lag and not being able to balance the throttle properly.

 

If you want big power for straight lines then dont start with a 205, go Rwd or preferably 4wd where you can put the power down.