HDI 90 INTERCOOLER FITTED

[lazarus79]

Hi as the title says, yesterday i fitted a 110 intercooler to my 90 and can confirm the following results;

Increase in power between 1,500 and 3,000 rpm,
No real increase/decrease in fuel consumption,
No smoking/overfuelling etc
Slight uneven tickover at cold start in morning that goes after about 30 secs.

If anyone is interested I can post a walkthrough on how to do it, its not quite as simple as you may think!

I did this with a view to remap soon, but can confirm it works fine without. Also the 90's boost is not variable by remap, so looking to fit a "doors" system to do that too. I think with the boost raised the results may be more impressive.

[john1412]

very good any pics ? what way did you run the piping from the turbo to the intercooler ? and did you use pipes from a 110 model?

[lazarus79]

110 pipes with some mods ! as i said if people would like i can do a walkthro with pics?

[omega]

110 pipes with some mods ! as i said if people would like i can do a walkthro with pics?

sounds good lets see how its done then please

[lazarus79]

ok so admins it wont let me attatch photos? says "sorry the board attchment quota has been reached" ? I have resized them down to fairly small?

ok well i used the print out that has been posted on here before for the pipes and intercooler. Mine is a later 406 hdi and so has the butterfly valve on the intake pipe so need to make sure whichever system you have you get the same to replace.

To start with I took a grinder to the plastic that covers where the intercooler should go, leaving a nice opening for it. The rubber stoppers are already there at the bottom of this (next to the rad) then i fitted the intercooler straight in no problem.

The intercooler has a vacuum hose at the top which you dont need on a 90 so i blanked this off with a screw and some blue sealer, but i dare say this would be a good place to run a boost guage off if you so wanted. I attached the top mount of the intercooler with a zip tie.

Working at the top for now, I took off the elbow from the right hand side of the intake manifold and replaced it with the new one i had from the 110. (bends forwards not down) then the butterfly valve and then the new pipe to to top of the intercooler also off a 110. The butterfly valve has a vacuum pipe that runs to the boost solenoid on the scuttle. The 90's hose wont reach where the 110's butterfly is so I had to buy a new longer pipe.

Working at the bottom I took off the mountings for the power steering pipe that runs under the engine, and removed the no longer needed intake pipe that runs from the output of the turbo to the old elbow on the intake manifold.

Next bit was tricky.... It seems the turbo of the 110 exits at a different angle to the 90 and so the small rubber hose that connects the solid plastic pipe that runs under the engine to the turbo would not surfice. So I went to a scrappy and bought for a fiver a rad hose the same bore size with a 45 degree angle that was slightly longer (cut it to size). I Connected this to the turbo exit, then to the solid turbo pipe that runs under the engine, then the rubber "s" shape hose which connected to the bottom of the intercooler.

Lastly I zip tied up the power steering pipe that runs under the engine and cut the right hand side of the engine cover so it would fit on with the new intercooler pipe.

Job done!

So to summise: (hopefully we can get pics sorted somehow)

you need:

110 INTERCOOLER
110 TOP HOSE
110 BUTTERFLY VALVE (LATER MODELS)
110 INTAKE ELBOW
110 LOWER INTERCOOLER "S" SHAPE HOSE
110 LOWER INTERCOOLER PLASTIC SOLID HOSE
LONGER VACUUM HOSE FOR BUTTERFLY VALVE ON TOP
LONGER HOSE FROM TURBO OUTLET TO LOWER PLASTIC PIPE (PREF WITH 45 DEGREE BEND)
SCREW AND SEALER TO BLOCK UP TOP OF INTERCOOLER
ZIP TIES!

I bought all of the above for under £100 delivered

Hope it helps, hopefully get pics up with advice on how!

[steve_earwig]

I was expecting no change at all but nice to know there are gains to be had. I'm thinking yours is a Siemen's so not remappable, what's this "door's" system? I would Google it but I think I'd end up in B&Q...

Edit: You need a photobucket account, you upload the pics to that and then it'll give you links for noticeboard/forums. 640x480 is a good size for the forum as even Welly will be able to see them on his black and white set Photobucket can resize for you, mine is set (I'm not sure how I did it, perhaps it's the default ) so it resizes when I upload them.

[Welly]

I'm amazed that this mod has increased performance because all the tuners out there would have said no

I stood and spoke to a techy guy at the NEC's AutoSport show once (from that place who developed the Rallying TDi Golf - can't remember who) and he said adding an intercooler would do nothing without the extra fuel delivery. Basically all you are doing is cooling the intake air (which would indeed be slightly more dense with more oxygen content) I'd wager that in winter the subsequent over-cooling may make it smoke more by quenching the combustion process. The ideal intake air temp for a Diesel is about 15 deg C (which is what you'd get at the moment).

I'm glad you're pleased with the work and pleased you shared the results with the forum.

*finishes eating humble pie*

[CountryPug]

Awesome, can't wait to see some pics.

I love it when a plan comes together

[lazarus79]

hey everyone...

the gains are not massive but are there. Yes its the siemens system. I looked into it, some places can do it on the bench but i found a place (Ajec Racing) where i used to work who looked it up on his software and quoted back to me the ecu number etc and said yes no problem? we shall see!! he quoted me this "doors" system says he has done it b4. When he looked up the system he told me everything he could tune and boost wasnt one of them.

I think the gains are prolly cos traditionally the colder the air the more dense. When i studied the higher mechanics course (NVQ3) the theories are there and "hilliers" talks about it a great deal.

You guys may know the 406 system far better then me however, but I would have thought the ecu would refuel dependant upon what it had anyway, an example of this is after you have disconnected the battery for over 30 mins the ecu resets to actory and the car runs worse for a bit.

Anyhoos, It seems to be working, but dont expect big gains until remaps etc etc, i'll keep you posted if he turns round and says cant do it !! hahaha A major reason for me fitting the cooler was off to malaga in it hopefully next month and thought it may help, and for £100 and the experience of fittin it, why not?! lol

[lazarus79]

oh and i would have said that more colder denser air required less fuelling hence we thought possible smoking which it isnt yet?

[Welly]

Once the air has passed over the incoming air mass meter the ECU doesn't know what happens to it next and it won't know that you've cooled it further, there's no Oxygen sensor in the exhaust to do a final check of the process.

The ECU looks at Air Mass, coolant temp and throttle position to determine how much fuel to put in (unless I'm missing something).

I'm no expert on HDi fuelling by any means but it won't react like a petrol does.

I be interested in your remap soon

[lazarus79]

yes i agree that would make sense. seems a little on the basic side!! yeah will keep you posted, just gotta save some pennies. Maybe he was just chattin poop, but seemed to know what he was on about and its a rolling road centre so will get a print out.

[swiss]

Basic theory is, of course, more air + more fuel = more power. Adding simply one or the other probably isn't going to achieve very much, as supported by the evidence of the OP's observations.

Having said that supplying more air may well lead to more efficient combustion, leading in turn to a little more power. This is one of the objectives of forced induction in the first place.

But as has been said, to really make use of the extra air you're gonna want more fuel. Which is why all you lot with HDIs bought the wrong car, 'cos if you had proper engines (ie. TDis) you could do it yerselves with spanners instead of electrickery ^_^

Nice job on fitting the IC though, it's been talked to death 'round these parts.

[lazarus79]

Ok so here are the photos:



This is the new vacuum hose from the solenoid on the right of the scuttle that goes to the new butterfly valve on the intake pipe


This is the top of the intercooler complete with zip tie on top mount and screw to blank off vacuum hose (any vacuum related product could connect here)


View from the top of the engine with the cover off


This is the new 110's replacement elbow on the right of the intake manifold and you can just see the butterfly valve at the end which connects to the solenoid above


This is the most important one, you are looking at the bottom of the turbo under the car. You can just see the new rubber hose i got from a scrappy that is longer then the original and has a slight curve in it. you can just see at the other end of it the solid plastic pipe that goes underneath the engine sump which then in turn connects to the rubber "s" shape one and then to the bottom of the 'cooler.

If anyone has the link for the technical diagram thats on here of the parts you need i guess here would be a good place to put it to illustrate what im on about!!

[steve_earwig]

I think that'll be these:
DW10TD


DW10ATED