oh, balls. i've bought a PB ported/polished head to go with it, so thats out. What about this metal HG idea then? i've been in and out about that. First i thought i would go for one, then thought it mite lower the compression and give me less performance, so i decided again. But if lowering the compression back to 10.4/1 is what needs to be done for the ECU to provide a decent map with the engine, then maybe it's the best way to go?
If you stick a lumpy cam in it you'll be fine at the finer compression ... I can't help thinking that Toyotec has just been unlucky... there are good and bad engines in every size. My 2.0 8v with a std PB head also ran out of puff at higher revs, but not as low as 4500 rpm - more like 5500. I can't help thinking that the 3A Toyotec has is just a bit of a tight engine. I'd also recommend adjusting the AFM spring on a digifant if you fit a 2.0, and although it's not an exact science, I'd expect a 'fast road' type chip is going to help a bit. Not as effective as a full megasquirt mapping, but a lot quicker and cheaper to do.
The game was all over @ 4500 with 3A head, 2E inlet and 2E throttle body. Was made better with ABF TB. But still not what I expected for a 2.0 with what looked like the better clyinder head. PB head system made the engine feel like a stronger 1.8 8v but still not to my expectations. My target is a 15.5secs@93mph 5dr family grocery getter. Bar the ECU the parts to do this will be STD/VAG and I will post it up here what I did.
Did you put new shells in the 3A when you fitted it? I'm surprised that my stock motor revved better with all standard PB bits and no development.
couple of questions- what do you call a lumpy cam? i'm torn between 268 and 272. didn't want to go any higher than that, really also i have wound the spring back three notches already on the standard engine, will it need to go a bit more than that once i fit the 2E bottom end? 'Fast road' chip, like a blitzchip or something? and for what application, PB, or 2E? lastly, would you recommend a metal HG to lower the compression to match the PB's, or a paper gasket to raise the compression for more performance? which one will give me better results?
This head swaps were done back to back in my quest for more. I even replaced the ECUs and attempted to install a large BMW E34 530i AFM which had to be removed. Stock motor revved to redline 6700, in 3rd and 4th with both PB head and 3A head with ABF TB (not 2E TB though). The engine has since been rebuillt (2005) with new rings from ECP after rehoning and VAG bearings shells, metal gasket etc and the 3A head reinstalled with modified Bora exhaust tubular manifold. Dont get me wrong If you were to drive the car you may find it drives well. But theres more in it. Especially as my old 1.8 EV thing was faster. This is my main target.
Any gasket will do mate. Metal one or fibre one does not make a difference in the real world. If AFRs and spark maps are not right for this set-up with STD digifant 2 ECU then a recalibration should help if it will address the areas that are not calibrated well for the is larger engine. As I said before in this thread the eproms in the digi ECU deal with fueling and not spark. And its the spark maps that need addressing for this motor to be more responsive.
Either one of those cams is a bit lumpier than standard. Personally I've gone for the 272. I wouldn't do anything to lower the compression. Provided you can avoid pinking (and I'd run 98/99 RON fuel on a modded engine) then higher compression will always give you more power potential. On chips, match it to the ECU... I'm not sure if they're interchangeable between the PB and 2E, so I'd play it safe unless you know for sure. Blitzchip seem to offer decent value for money, from reviews on here. I bought one, but sold the car before I got it fitted. Wind the spring back too far and it might just run too rich all the time. Hard to tell for sure without a gas analyser.
the ported/polished head i've got has had a skim as well, so that will obviously lower the compression even more. Will this be ok? toyotec has now got me wondering whether any drop in compression will cause me to lose power through mis-matched ECU. and how the hell would i get the spark map recalibrated??? would a custom re-map do it, or is this just EPROM based? is stand alone engine management the only way to solve it?
The skim will raise compression, but if it's a light skim it won't do much. There are plenty of people out there who've run digi management on 2.0 8v digi cars and got up to around 150 bhp, without pinking problems. The standard digi runs too lean to maximise power, so the AFM spring and chip will help. I'm sure Toyotec's right, that to optimise the power from the engine you need an ignition remap, but you can get good results without going to that length.
cool, well i've bought all the gear now, so it will be happening, think i'll take the gamble and go for a fibre headgasket, make the most of the extra compression. After blitzchip fitting, is co2 adjustment recommended, or should i do this before fitting, to let the blitzchip do it's thing? i've read that basically the blitzchip will mess around with the fuelling, so i don't want to then go and lean it back out to 1.8% co2 do i? ignition remap.....like i said, can this be done through a standard remapping company such as superchips, or will i need to scrap the PB ecu and go for standalone management? i thought companies such as superchips would just deal with the fuelling maps.
Stick it all in and see how it runs... I think adjusting the mixture on a digi only affects it at idle speeds, so doesn't make much difference - I'm not 100% sure about that though... I haven't heard of anyone managing to remap the digi ignition curve using the original ECU. It'll probably be good as it is anyway. Which cam did you go for?
Going for the 268, i think. there's one on ebay i think i'm getting. apparently there isn't that much difference, but i'd rather have it come 'on cam' a bit earlier tbh, i don't usually go above 5k, town driving and all that, so ideally i need the optimum power between 2.5k and 5.5k RPM, i think the 268 tails off at about 6, so that should be perfect. Should work well with my Vagobonds head which arrived yesterday and looks the business.
Sure... did you go for bigger exhaust valves, which will help a 2.0 rev a bit more? If not, then the 268 will definitely match the power band of the engine a bit better. If you're contemplating a used cam, be very careful, and get measurements and pictures of the cam lobes to check for wear. Philip Walker on here sells Newman Cams (and other stuff) on ebay as PW Motorsport. You won't have any problems with his stuff... it's generally all brand new.
On the gasket issue nobody ever seems to mention piston quench (I've recently worked on a Chevy V8 and lots of books/websites bang on about it quite a lot). From this I thought thicker head gaskets were a bad idea. I know there's not much in the size difference between fibre and metal gaskets but could it make the difference between a pinking engine or not ?
Stacking metal gaskets is a tried & tested method of dropping the compression, so a thicker gasket should work as well. However it would drop it too much in this application, I think its more for turboing n/a lumps! I've never heard of piston quench before, will have to read up on it
piston quench, i've heard of that... its something to do with the piston 'squashing' the mixture against the cylinder head or something, i remember reading about it in the standard abrasives porting/polishing guide. I think i'll definitely go for the fibre gasket. mikehorsb: i didn't go for the bigger exhaust valves, no. just a stage 1 port/polish by Vagobonds, through a contact on here. Head looks great, and besides the usual porting/flowing work and valve de-shrouding it's also sporting multi angle valve seats. I was very keen to get this done, as i've heard this gives awesome gains. bought the 268 cam now, so we'll see what thats like when it arrives! i'm getting itchy to start this now! Just got to buy my last few things, headgasket, PB manifold gaskets, engine oil etc etc and i should be ready to go! think i'll post some pics when i start it!
