TDI with a 4L65 automatic in a Jeep TJ

[mcneil]

I think I have my plan for the intake plumbing.

Something like this:

Except that my intercooler is from a Golf, and it's completely road-blasted and caked full of grime. When I tried to remove the IAT/MAP sensor to clean it up, the screws snapped off in the plastic. I'm considering switching to the later Passat intercooler, which looks this and is slightly larger.

I did some more measuring and abandoned the front mount IC idea. It's not impossible, it just means fabricating a flange to space the radiator back 4", and a custom IC is pretty expensive.

 

[mcneil]

Alternative plan.. this requires less fabrication work and uses an ALH type IC.

Too hot to be outside in the daylight this weekend, so I'm doing some reading on intercoolers. I found a lot of good info, particularly from some of the 1.8T guys. Seems like its easy to end up with a poorly designed core if you're not careful. I also found that the passat intercooler I had my eye on would be a tight squeeze in that location, hence the concept of going back to the OEM ALH IC.

 

[greengeeker]

I very much prefer your 2nd layout but you're still left with the issue of airflow on your intercooler. The natural flow path (in terms of high pressure regions to low pressure regions) is going to be from the engine compartment and up out the hood which would be pushing post radiator temp air through your intercooler. You'll be fighting a losing battle if you try push air down into the engine compartment especially if your electric radiator fan turns on. IMHO I would work hard on getting a FMIC in front of your radiator...I realize this is VERY difficult to package in any Jeep.

 

[mcneil]

I think I could do a FMIC if I could find a core that's around 18" high by 19-3/8" wide. That would fit right in front of the Jeep radiator, which has space to come back a few inches.
edit: inlet & outlet need to both be on the passenger side.. no room top or bottom. May be able to squeeze one pipe out the driver's side.
double edit: yep, if the pipe exits straight out the top third of the tank, it'll clear the fender. Also there's almost 23" of width available.

Kind of like this (in red, ignore the IC):

I just ran an errand in the Jetta with a thermocouple hanging in the breeze behind the radiator fan to see how hot the air is coming off the radiator. On a 95F day, I saw temps as high as 154F. That's pretty hot for an IC to swallow.

 

[greengeeker]

I put this guy in my TDI Ranger and modified it a little bit.

I'm sure you could find a slightly bigger FMIC if you wanted.

 

[joker5k1]

Im not sure if you are willing to modify you hood. However if you feel comfortable doing so you could add a top mount intercooler similar to a subaru like was done http://m.flickr.com/#/photos/10201173@N06/839232460/ sorry if linking is a no-no.

 

[mcneil]

Im not sure if you are willing to modify you hood. However if you feel comfortable doing so you could add a top mount intercooler similar to a subaru like was done http://m.flickr.com/#/photos/10201173@N06/839232460/ sorry if linking is a no-no.

I thought hard about top mount ICs for this - I called up a friend who has a couple All-Trac Celicas and a WRX for his thoughts on it. Both those cars have a good aero design to the front end, and the hood scoop location works. On the blunt-nosed jeep, air wants to exit any holes in the hood. Like greengeeker said, the fan just ends up fighting it.

I put this guy in my TDI Ranger and modified it a little bit.

I'm sure you could find a slightly bigger FMIC if you wanted.

How important do you think it is to have the radiator cooling fan sucking through the FMIC? I had been thinking about mounting the FMIC tight enough to the radiator that all air through the radiator goes through the FMIC first, and I only need one fan.

If I kept some more space between the FMIC and the radiator, I would have a lot more options on cores, bigger or smaller. Saab 9000 and Volvo 740 look like they have inlets/outlets in about the right spot.

 

[Whitbread]

What about this guy? Can be had on ebay for cheap. http://www.godspeedproject.com/Godspeed-Intercooler/v-mount-intercooler

 

[mcneil]

That may work, though as I was poking around today, it looks like something with both inlet & outlet on the driver's side would work better.

Also, I think I'm set on a FMIC at this point. I've been measuring 70F temp rises in the air blowing across the radiator in my jetta. Too hot for an intercooler.

I'm going to try and see if I can fit the OEM intercooler in as a front mount. Since I already have one, it'll save me time & money, and if I can stuff that big 3.5" thick core in there, I can upgrade to a Godspeed or Treadstone later.

 

[mcneil]

FMIC plan in the works:

Some silicone 90s & 45s are showing up today.. if everything fits, I'll start working on a bracket.

 

[toohighpsi]

Just an opinion, but if you are going to the trouble to relocate the radiator back to give yourself some front mount room, I would go with a much larger and more efficient core. There are plenty of cheap options for sourcing one, and you really can do a lot better than the small oem vw ones. Keeping that intake air cool will make more consistent power, and lower smoke and egts. You're going to be working that tdi a bit harder than its stock application, the aerodynamics of that Jeep are going to keep you in quite a bit of boost at highway speeds. I would suggest finding something like an Isuzu NPR core, or one of the universal bar and plate types on ebay. The bigger and heavier the better as far as intercoolers go, that way you have a lot of thermal mass to soak up the heat when you really get on the boost.

Project is looking great so far, I've been following along for awhile. I've got an AHU sitting in the corner of the shop, and have daydreamed about putting it in a YJ for awhile now.

Putting this monster in a 2012 GTI right now at the shop:

 

[mcneil]

Just an opinion, but if you are going to the trouble to relocate the radiator back to give yourself some front mount room, I would go with a much larger and more efficient core. There are plenty of cheap options for sourcing one, and you really can do a lot better than the small oem vw ones. Keeping that intake air cool will make more consistent power, and lower smoke and egts. You're going to be working that tdi a bit harder than its stock application, the aerodynamics of that Jeep are going to keep you in quite a bit of boost at highway speeds. I would suggest finding something like an Isuzu NPR core, or one of the universal bar and plate types on ebay. The bigger and heavier the better as far as intercoolers go, that way you have a lot of thermal mass to soak up the heat when you really get on the boost.

Someday, someday.. with my radiator spaced back, I'll be able to run just about any FMIC.

It looks like the TJ radiator can come back about 3" without interference, except for a little corner next to the steering shaft which is easy to trim up.

I just finished the bracket for the stock intercooler yesterday. No pictures, because it is the ugliest bracket I have ever made. My temporary wood block on the radiator is tig welded fab-art compared to this abomination. But it does the job, and it was done in 2 hours.

I'm putting more effort into the radiator spacing brackets, because those will stay when I go to a better intercooler.

 

[mcneil]

Some pictures of the ugly bracket

Two 1.5" x 3" sections of tube space the radiator back to clear the FMIC.
3" push back is the farthest you can go on the TJ before interference with steering parts, PS lines, or coolant resevoir. But 3" is enough for any type of core you might want to run

The only squeeze point is around the stock airbox, and I'm still not sure I'm going to use it.

But with a bit of trimming I should be able to clear a 2" dia pipe through here:

Several boxes of pipe & couplers are on order, so this should come together over the next few weeks.

 

[mcneil]

Made a bit of progress on the intercooler piping. The box of pipe has been cut to size, now I just need to find what we did with the bead roller at work.

I used aluminum tube for most of the plumbing, but the section that goes through my radiator spacer is stainless. I punched through the c-channel with a hole saw then welded the pipe to the channel - makes a nice sturdy anchor point for the rest of the plumbing

Still have the stock jeep airbox in there.

Intercooler up front. That one stock hose is actually really convenient if you have to make a short radius 90 deg bend. I still need to order another silicone 90.

Top view.. it will get a little more crowded once I put the pipe sections in.

Should have the pipe sections beaded this week sometime, then I'll be done with IC & intake.

 

[jimbote]

kudos for going the extra mile and putting the IC up front, your IAT's will thank you

 

[greengeeker]

Really cool that your pipes pass through your radiator spacer! Keep up the good work.

 

[mcneil]

kudos for going the extra mile and putting the IC up front, your IAT's will thank you

All it took was a 2' length of 3" box tube sawn in half. The Jeep sheetmetal has some good attachment points, I'll get some better pictures of that later.

 

[mcneil]

Really cool that your pipes pass through your radiator spacer! Keep up the good work.

Here's what that spacer looks like with the pipes going through it:

The harbor freight crimper trick for beading intercooler pipe works pretty well. Just chop off the end of the $5 HF lineman's crimpers, polish them up, and you can form a bead by walking them around the pipe.

Here's the intercooler piping route. Stretch your imagination and pretend that's a huge FMIC there instead of the smog-required OEM one. I'd say there's no reason not to put the IC up front on a jeep swap. And if you're not in California, there's no good reason to use the OEM one. It uses all 3" of the radiator spacing and is still tight.

I also got the heater hard line fixed up. Cut & welded the nipple to shorten the pipe, and brazed a plug the unused port.

My TIG welding is getting better. I think I'm ready to try aluminum intercooler tube.. which is good, since I have a weld I have to make (see the blue tape in the above pics of the pipe routing).

Was there two different o-ring sizes for the hard pipe? This o-ring didn't work, so I tried the rectangular shaped one.. didn't work either. I'm going to try trimming down the rectangular and seeing if that works.

 

[greengeeker]

Yes, two different "widths" for those orings.

 

[mcneil]

Yes, two different "widths" for those orings.

Aha, got it. I had one in my kit that fit.

Also, we setup a powder coating area at work, so I tried that out for the first time last night. Definitely better than paint, though I need to work on getting better coverage.

 

[jimbote]

one man show!!.... great work ... i really dig the spacer/bulkhead intercooler pipe pass through .... and the lineman plier bead roller trick is pure genius !

 

[mcneil]

one man show!!.... great work ... i really dig the spacer/bulkhead intercooler pipe pass through .... and the lineman plier bead roller trick is pure genius !

Did I mention we have a buffing wheel at work

Pipe from the turbo outlet needed a reducer welded onto it.. this was my first attempted at TIG'ing aluminum tube.
(PS: this is the better side of the bead)

 

[mcneil]

I didn't touch the jeep this weekend, instead I gave my daily driver some much needed attention. All the PM basics plus new headlight lenses, new chin spoiler, and a ilovetacotaco intercooler.

 

[mcneil]

Here's something I should have done with the body off - modify the firewall for more clearance. I was halfway through CAD design of a vac pump block-off plate when my cheapness kicked in and I decided I didn't want to fork over $300 for a reliable electric vac pump. I had some time today so I tore into the firewall and made room for the pump. Only needed about 1-2", and there's plenty of space between the firewall and the HVAC box.

Now to go buy a 5 gallon bucket of seam sealer. Ended up being much uglier than I wanted, since my welder was refusing to run .023" wire, and I had to do it with .030".

Also, I ended up going with a ALH-auto coolant flange, it fits nicely. After the welding, I got that and the rest of the coolant hard line attachments buttoned up.

 

[mcneil]

Looking at the vac pump, and thinking about how much, or even if, I want to modify it.

Is the check valve built into the nipple, or is that just a filter in there?

I'm thinking about replacing that nipple with an elbow fitting instead. Clearance is still real tight back there even after the sheet metal work.

 

[greengeeker]

Yes, there is just a check valve underneath the nipple. Might be a good idea to remove that failure point anyway - the aluminum around the base of the nipple wears/loosens up over time and you lose compression on the gasket resulting in low vacuum levels.

 

[mcneil]

I think I'm going to be ok with just a rubber elbow on the nipple for now, but it's going to rub the body under high flex so I'll have to modify the pump later.

I took a break from the firewall clearance issues and worked up some brackets and lines. Dipstick mounting bracket and power steering line - I got some braze-on 6 AN male fittings. They make life easier than the flares, since most of the pre-made AN hoses come with female ends.

 

[mcneil]

I've got the PS pressure hose on order. I found a AN adapter for the VW banjo bolt fitting - basically it adapts from the 16mm thread with a washer seal to a 6-AN male. Thank you VW for conveniently locating the PS pump on the same side of the motor as the jeep steering box.

Didn't get much else done this week as I had another jeep to work on:

My 2 yr old daughter went as a jeep for halloween - the roll bars are actually the shoulder straps.

 

[mcneil]

I'm going to be controlling the gauges with an Arduino and a Melexis 10407 gauge driver. This is my first serious microcontroller project, so expect some learning & evolution. The way it works, the Arduino will read analog values from sensors or other inputs and write a command to the Melexis over a SPI bus. The Melexis generates the appropriate PWM signals to move the needles to the commanded locations.

The idea is that I can bolt the instrument cluster back into the dash without having to mess with any of the wiring for lights or turn signals. Anytime I need to make a calibration change, I just reprogram the Arduino. The only other wiring I have to do is the check-engine light, which thanks to Jimbote is pretty easy.

100 mph yeah!

Let's see if videos work:

 

[mcneil]

Turns out that the automatic water outlet on the head still has a tube in an impossible location, even after my firewall mods. I cleaned up the old water neck and made a block off plate for the heater line. I'll tee the heater line off the other hose at some point.

I'm really enjoying this powder coating thing, if you can't tell.