hi all

I wonder if anyone can help?

i keep on seeing 1.8t remaps with 1 bar boost settings....

whats the max boost anyone runs on a standard 1.8t? - one bar is so conservative!

from the picture to the left you'll see i dont drive a skoda - i run overboost to 1.7bar and maintained 1.5bar (about 300bhpish 320lb/ft torque)

Thinking of buying an 'everyday' car - as my car is... well... eerr not to practical!

hence an octavia - has to be 4x4 as IMO fwd and >250bhp is mad - torque steer from one side of the road to the other! (i have experience of this in a 300bhp golf mk4)

anyone got a big turboed 4x4?

regards

Marc

Max boost for me is 1.5 bar, and close to that at redline. I'm at 2800m of altitude, so comparing bhp is ridiculous, but I'm around 260bhp with 1.4 bar at redline on 95 Euro-octane. Of course, that's not with the original turbo. The original turbo won't even do 1 bar at redline. I'm hoping for 350bhp at 1000m altitude, and 1.3 bar at redline using 104 octane. An extra bit will then be achieved by a small 50 shot of nitrous. The competition is a modified 1993 Mazda RX-7 with 450bhp. We'll see.

Regarding max boost ever, there's MKIV Golfs running 1.8 bar. Nobody's really seen the mechanical max boost for a 1.8T. The MAP sensor does however max out at 2 bar. The real engine killer is a claimed max torque of around 320 ft lbs. The rods and wristpins seem to go. Those are daily drivers btw. Also, here's a 460+bhp 1.8t with standard internals.

http://www.vwturbo.com/turboinfo/102803/400whpvschippeda4.jpg

Howcome you don't like driving your Alpha every day?

Speedy G

As far as i know.. the turbo maxes out at around 1.6bar.

some people on seatcupra.net (cue badger bill) have done IHI turbo conversions.. Bill Brockbanks (badger 5)Yellow ibiza 1.8t is running about 350bhp and fwd.

#Howcome you don't like driving your Alpha every day?#

Its a lancia evolution 1.... ;-)

several reasons:

1) does 8 to 20mpg on optimax 98 ron = big cost in the uk

2) needs extensive love at service time - cam belts at 20k!

suspension bushes antiroll bar drop links every 5k!

3) eats tyres on the road - 4k for a set of 4!

4) very hard ride and noisy (basically a road going rally car minus cage)

hence more sane transport required.... i know 300bhp skoda doesnt sound sane to some but in comparison it is.

these boost figures sound more like it! -interesting that the standard turbo can only attain 1bar. Does the 1.8t have an overboost facility? or is it all or nothing all the time?

Marc

Neo, it depends what turbo you're talking about. The smaller, older cars with drive by wire had smaller turbos that won't go over 1.2 bar. The newer ones will do 1.6, and I've even heard of higher numbers. However, it's not about boost. It's where you get the boost. The stock turbos boost for torque, so they die beyond 5krpm and only lucky ones get even close to 1 bar at redline.

Overboost facility? Not getting what you mean.

Speedy G

Re Overboost, not sure you'd formally call it a facility (eg.where you get 30 secs max of higher boost) but its certainly a feature of Jabba's remaps at lower revs I believe.

Overboost can be apparent on a Jabba'd car, but this can be mapped out.

The power will still be there, but the "edge" is apparently lost. My car occasionally shows this overboost symptom, but its easy to get used to it, and no-one who has been in the car has ever commented on it.

Overboost......

a few manufactures (fiat mainly but i think ford Tdcis do it as well) build in an overboost into the chip - usually for two reasons

1) to allow a short burst (3 seconds or so) of extra boost in such a way that you aint gonna melt pistons

2) limits boost (by not having the overboost available ) in lower gears to stop transmision failure/reduce wheelspin if fwd

dont get confused with boost 'spikes' very different

1.6 bar on the latest turbos.... hhhmmnnn 240bhp - i can see where the different turbo comes into play! soooooo restrictive

what sort of torque difference is there between 1.6bar small and big turbo at 1.6bar any ideas? afterall we all know BHP figures are pretty meaningless

Is the bhps at the wheels figures by the way?

marc

Overboost? I guess you mean boost overshooting. Say the chip is meant for 1 bar, but it overshoots the 1 bar setting when boost is on it's way up, then stabilizes to 1 bar and then the boost starts to drop because the turbo can't hold it at high RPMs. This is easily done with N75 valves or an MBC on top of the N75. You can also get a map that does that. It's just a slow reaction of the wastegate control, so it overshoots. You can get more torque that way, and you may get a little faster spoolup as well since the wastegate is held closed until the target boost is reached, then it opens up.

This overshooting bit is not a good idea on all engines. Motronic 7 engines (drive by wire) can adjust injectors to go beyond 16.32 ms (85% duty cycle at 6500 RPM) at low RPMs. Mine is an AGU engine which uses Motronic 3. My ECU code has a limit to the injector pulse width which is 16.32ms irregardless of RPM. I max out my injectors (16.32ms) from 3400 RPM all the way to redline. That means that overshoot would also produce a lean condition. On top of that turbo cars are prone to detonation at that exact point, so it's not the best idea to do the overshoot bit.

Here's a VAG-Com log of my Motronic 3 setup:

Speedy G

aarrhhhh......

very different - the overboost system is a solenoid controlled loop which is designed to 'trick' the wastegate.

what i think your describing is turbo inaficencies at a particular rev range - would make sense due to the small turbo size.

my turbo chip is set at 1.7bar over boost - hold for 3 seconds then drops to 1.5bar, holds for a bit and as the revs increase the turbo goes out of its effective capacity reducing to say 1.3/1.4bar

wooohhh!!! injectors at capacity! i think you need bigger injectors!? and increased fuel pressure?

interesting that the drive by wire can adjust more..... definate torque advantage

BHP meaningless? Ok, I want to see you beat a Honda S2000 off the line 0-100MPH or a 1/4 mile, on a 1.8T with 260ft lbs of torque at 1.6 bar (making around 240bhp), and the S2000 with just 153 ft lbs and 240hp. They're about the same weight. CYA!

Regarding your 1.6 bar question... as I said before, it depends on where you have boost. If your engine had no turbo and it makes peak torque at 3000 RPM, having 1 bar of boost at that RPM would pretty much double your torque (stock turbo). A big turbo like a T3/T4E 50 trim would only spool up at around 4krpm, so it would double the non-turbo torque at that RPM, which would be significantly less. An example:

Stock turbo Revo chip: 232 ft lbs at 3krpm

IHI Jabba stage I: 270 ft lbs at 5.4krpm

232 ft lbs is 314Nm and 275 ft lbs is 367Nm

Speedy G

Ha! Never heard of that overboost solenoid. My boost controller can do it, but as I described. The N75 valves have pretty much the same effect.

Yep, I'm at a disadvantage with motronic 3 in terms of torque, but remember those are 380ml injectors running at 4 bar. There's plenty of stuff going there. Also the log you saw was at 1.5+ bar, I was trying to figure out how high I could push it before EGTs screamed. I could've pushed it higher but the ECU started pulling timing and the ride got bumpy.

Speedy G

# BHP meaningless? Ok, I want to see you beat a Honda S2000 off the line 0-100MPH or a 1/4 mile, on a 1.8T with 260ft lbs of torque at 1.6 bar (making around 240bhp), and the S2000 with just 153 ft lbs and 240hp. They're about the same weight. CYA!

#

BHP is relatively meaningless in 'real world driving' oposed to being able to hold on to one gear for a long time ;-)

S2000 - wouldnt stand a chance - too busy looking at themselves in the mirror!!!

50-70 in 4th with torque low bhp will be faster - unless your willing to drop to second gear in the s2000! - 1.8t wins!

My motor does 3seconds 50-70 in 4th - the target is get a skoda as fast but with comfort and space!

#I could've pushed it higher but the ECU started pulling timing and the ride got bumpy.#

he he - i know what you mean....

gets a bit worrying when your pushing to the limit!

one of my idiot mates overrided the knock sensor - the boost/fuel ratio was somewhat wrong - melted 2 valves and a piston! the valve debris shot out and wedged in the turbo...... whoops! expensive.

S2000 crowd comment... you described my old roommate.

Hey what displacement & number of valves is that Lancia? What turbo? How much does it weigh? From the sound of it, it sounds like the turbo is slightly undersized. That's why you get higher torque than BHP numbers. The equivalent in the 1.8T world can be done with a K04 or a GT28R, the latter being slightly bigger.

Here's a couple of dynos:

APR kit stage III with a GT28R

100 octane:

Regular super plus (98RON~=93 US octane)

K04 dyno I think Dahlback and Oetinger sell these in Europe:

235bhp

280 ftlbs of torque

Dahlback also has other larger kits. There's a 330bhp with 304 ft lbs of torque, but it's way overpriced and they change internals.

Speedy G

There's also a modified version of the TT 225 turbo (K04-020) that gets you up to 300bhp with around the same torque in ft lbs. The exhaust housing is modified to one from http://www.hgp-turbo.de/. The only problem is that fitting that on a regular Octavia 1.8T engine requires fabricating stuff.

Speedy G

PS

While I remember, the girlfriend's Mondeo TDCi has the overboost facility. Ford even market the facility in their advertising blurb about boosting torque rather than power - Yes I know its a diesel! Torque goes up to 254lb/ft from (memory) 228lb/ft'ish

Rob

#Hey what displacement & number of valves is that Lancia? What turbo? How much does it weigh? From the sound of it, it sounds like the turbo is slightly undersized. #

2000cc 16v twin cam with balancer shafts (however i've had my balancers removed in the quest for quicker pick up from low revs)

yes the turbo is a restriction - when the lancia works team rallied these they were subjected to restrictors in the turbo - therefore it was pointless fitting a larger one. just like current wrc cars - more torque than bhp

to be honest the engine self destructs along with the 4x4 transmision with more than 300bhp - fire ringed head gasket/block and very expensive valves etc

weight - 1300kg in road spec - however mine is one of a few which is lighter as it has no abs or aircon - it does however come factory fitted with intercooler waterspray! not bad for 1992!

some links if your interested - http://www.hf-integrale.co.uk/bbrphase2.htm

http://www.hf-integrale.co.uk/Overboost.htm

http://www.evocars.com/integrale_buyer_guide.htm#evoluzione

Hey I took a look at your overboost valve diagram. It works exactly like the 1.8T's N75 valve. It controls the boost above what the spring setting on the wastegate is. There's several flavours of N75, some of which will give you a slower or faster response of the wastegate, making some people happy with the mentioned boost spikes.

Speedy G

Mine runs 1.5 bar, dropping to 1.2 bar which it holds to about 5,500, 1 bar at 6000

hi all

hence an octavia - has to be 4x4 as IMO fwd and >250bhp is mad - torque steer from one side of the road to the other! (i have experience of this in a 300bhp golf mk4)

Marc

300+ in a MKIV is no problem on mine...

Did yours have the std diff in it?

Quaife in mine. No Torque steer at all.

Bill

300+ in a MKIV is no problem on mine...

Did yours have the std diff in it?

Quaife in mine. No Torque steer at all.

Bill

I have a Peloquin in mine. I love that thing. Recently I did a full boost U turn in first and only squeaks instead of squeals came from the front tires. The rear wheels slid quite a bit though. Nice!

Speedy G

Marc,

Back to your original point, I too had an Evo I (for a couple of years) which was the best car I've ever driven. Unfortunately, as you've mentioned they cost mega-bucks to run with poor mpg, a hard ride and a appetite for cam-belts (mine went taking all the valves with it - ouch!) :mad2:

However, I now own an Octy vRS and although it's not as quick, it's just as much fun to drive but with built in comfort, reliability, cheap running costs and I think just as much kudos as an Evo. :smile-l:

I reckon if you do end up buying an Octy (in whatever state of tune) you'll end up spending more time in it than your Evo, so come on, get a Skoda!!

:drive:

Andy

300+ in a MKIV is no problem on mine...

Did yours have the std diff in it?

Quaife in mine. No Torque steer at all.

Bill

Bill it did have a standard diff - hence the problem... - the one in question is jim's at awesome gti - more of a show car than anything - after the testdrive i bought an integrale instead - perhaps i was being unfair on it as it was never set up to be a road monster - more of a poser with 300bhp - it was quite expensive in comparison as well

Marc' date='

Back to your original point, I too had an Evo I (for a couple of years) which was the best car I've ever driven. Unfortunately, as you've mentioned they cost mega-bucks to run with poor mpg, a hard ride and a appetite for cam-belts (mine went taking all the valves with it - ouch!) :mad2:

However, I now own an Octy vRS and although it's not as quick, it's just as much fun to drive but with built in comfort, reliability, cheap running costs and I think just as much kudos as an Evo. :smile-l:

I reckon if you do end up buying an Octy (in whatever state of tune) you'll end up spending more time in it than your Evo, so come on, get a Skoda!!

:drive:

Andy[/quote']

the dreaded cam belts! 20k change a must!

i do confess after driving 2 vrs's i'm impressed - i managed to impress Carlos on the forum as well - as he ended up buying it after i took it round to show him it!

I think i need a test drive in a 4x4 then a vrs to compare really.

any idea what mpg you get out of a modded 4x4 anyone? i know the vrs was managing 24-28 when i had it for a week is the 4x4 much worse?

marc