AAZ – Water Meth, Exhaust, Injectors and Chinese Turbos & Manifold

[edb1984]

Hi All

After a few years of tinkering on 8V petrol VW engines, mostly K-Jet I have swapped over to dirty diesels and have just installed a AAZ into my MK1 Caddy so have some questions while I learn more about the older Diesels so bear with me.

Engine came to me already partly modified by previous owners, from taking a good look over it its got a PD130 intake, intercooler, K14 turbo, boost pin swapped out and although I haven’t checked yet I am pretty sure the governor has been modified too as fuelling doesn’t feel like its backing off.
The engine runs well - currently running at 16PSI on the turbo but after 3500K its just blowing hot air and loosing pressure and boost drops down progressively etc and EGT is raising substantially so have to back off on the pedal.

I am wanting to get some more power out of it, I don’t have the cash or time at the moment to post the pump over for a Giles mod although I hope that will come in the winter when it’s put to bed until next year, currently it feels as if its running about 100BHP, would be nice to get that up to the 130-140 mark if possible – I have got it booked in at the rolling road at the end of next month so fingers crossed for the results.

So in the meantime I am thinking I might make a few changes and want some advice if possible? – appreciate some of these questions have been asked before but some posts date back to almost 20 years ago so would appreciate some new answers if possible thanks 😊

What I am thinking I would like to do;
•   Go through the “Make your 1.9 faster” list of changes from this website although I expect most have already been done to this engine.
•   Swap turbo out for something larger with more puff to it that can keep up with the engine and keep the temps down a bit. – I understand this will change the spool time and don’t mind sacrificing a bit of time for a more substantial cool boost higher up the rev range
o   What “Off the shelf” turbos would you recommend that are readily available in the UK?
o   What exhaust manifold or adapter would you recommend? – interested to hear what others have used with larger or more efficient modern turbos to get them to fit right.
o   I have been looking at the maxpeedingrods generic “Universal” turbos, have had a few friends install them lately with good results – I understand it’s a gamble with the quality control, but I don’t mind that.

•   Injectors – wasn’t planning on changing until pump is done – do you agree?
•   2.5” stainless turboback exhaust
•   AEM Water Meth injection (Already got one left over from another project) – worth installing on a IDI? If anything I was hoping it would help with temps but would be interested to hear opinions.
•   ARP head bolts, but for sub 150BHP would I be okay with stock on the bottom end or would you recommend ARP mains as well?

thanks for any and all input 😊