How To: Build your own 4.0L turbo Cummins (Beware...170+ pics)

[Boostwerks.com]

Boostwerks-
How does your MAP sensor do when it see boost? It is only a 1 bar map sensor. What reading soes it send to the ecu under boost?
How do you stay in open loop when under boost? Do you control/limit the O2 sensor?
What is your IAT? under boost, as read by the OBD?

The map sensor does fine. The AEM has a voltage "clamp" that only allows the factory ECU to see the maximum voltage it would see normally N/A at WOT...IE the nominal atmospheric pressure at your altitude. In this way the factory ECU has no idea it's seeing boost. This is also why the AEM has it's own MAP sensor.

My 99 uses TPS and map sensor data to determine when to go into open loop just like it would normally. The ECU is almost always in open loop under boost. When it does however see boost in closed loop, it is usually due to low throttle conditions. In this case the O2 sensor offset comes into play along with the compensated fuel table to enrichen to roughly 13:1.

As for IAT's I'm honestly not sure. It's been a long time since I did a log of them. I'll try to get some readings for ya here soon. :thumbup:

 

[CobraMarty]

Thanks.

 

[Boostwerks.com]

More Updates!

A couple months ago I started to notice an exhaust "tick" noise coming from the engine bay. At first I thought maybe one of the V-band clamps had loosened up on the down pipe, but everything checked out. I've been waiting for an opportunity to tear into it to figure out what was leaking, and finally got my chance last weekend. What I found was 3 of the bottom manifold bolts had loosened up enough to allow the exhaust gases to burn out the graphite material of the gasket I used. Also the heat expansion of the manifold had gouged the graphite causing the bolts to loose their tension.

Lesson learned? DO NOT use a graphite faced gasket! Talking with the 4.0L experts at Hesco, we developed a plan to eliminate the gasket completely. We decided to use Permatex's high temp copper RTV around the exhaust ports, and an anerobic liquid gasket for the intake manifold. In addition to the sealants, I replaced all of the bolts with chromoly studs from ARP and mil spec lock nuts to ensure everything keeps it's tension.

The good news is that other than the gasket going to hell, everything else seems to be holding up just fine. While I was in there though, I fabbed in some new upper shock mounts that increase overall travel by about 3 inches and allow a regular eyelet style shock. I had thought about trying to make these to sell, but after the install I'm not so sure. To cut out the area in the body is a HUGE pita if you don't have access to a plasma. Also there are several weird angles in the factory sheetmetal that just make it hard to position the mount. After about 10 hours of cutting, cusing, grinding, yelling, drinking, cutting, yelling and welding I finally had one side done.

The Turbo looks fantastic inside and out and has zero shaft play.

 

[Boostwerks.com]

Sorry for the pic randomness... Uploading more as I type...

 

[Boostwerks.com]

For some reason my last batch of pics didn't save to my phone, so I'll need to snap them again tomorrow.

I should also mention the shock mounts arn't finished quite yet. I'm going to box in the sides and finish the rosettes at work. My little pos mig just doesn't have the heat to get a good bead down on 3/16" plate.

 

[XJCasper]

Do you have a part number on those bolts?

 

[Boostwerks.com]

Do you have a part number on those bolts?

94358A330
Mcmaster PN: 94358A330

They're not exactly cheap unfortunetly.

http://www.mcmaster.com/WebParts/Co...arsetind=1&ScreenWidth=1440&McMMainWidth=1356

 

[Boostwerks.com]

More pixs...

Permatex's anerobic sealer ready to go...

Everything back together with the WJ PS pump.

finish welding the brackets and some droop shots. For reference I'm running 12" Travel Bilsteins @ about 5" of lift. Approximately 4.5" of uptravel.

Maxed out the heims so we threw on some misalignment spacers.

Shot of the back:

DS angle still looks pretty good

Back on all 4's...

All I can say is that I love it. No more exhaust tick, and it rides like a caddy.

Up next is a valve body upgrade thanks to child9, and then...the dyno :O

 

[XJCasper]

Thank you. Yes, ARP is spendy, but I want to make sure I get any issues handled out ahead of time. Thats why it is taking my parts purchasing for this, so long.


Dyno, yes please.

 

[Rockdrummer93]

If you don't mind me asking.. what wilwood calibers are you using. and how did you mount them. Did you have to change or alter the knuckle or mounting location. Or was it a direct bolt up? what else did you need to make them work? any info would help thanks! oh and great build btw.

 

[merdock69]

Did you put anything on the head side threads of the studs when you installed them? Or did you just install them dry?

Thanks,

 

[CobraMarty]

I don't remember and can't find it, but did you have to 'clamp' the map sensor?

 

[bpas328xi]

The map sensor does fine. The AEM has a voltage "clamp" that only allows the factory ECU to see the maximum voltage it would see normally N/A at WOT...IE the nominal atmospheric pressure at your altitude. In this way the factory ECU has no idea it's seeing boost. This is also why the AEM has it's own MAP sensor.

I don't remember and can't find it, but did you have to 'clamp' the map sensor?

Lol. :doh:

 

[Boostwerks.com]

So I found out the hard way, that if your going to replace the bolts with the ARP studs, you should also replace the two factory studs at each end of the head as well. :smsoap:

After work one night, I decided to pop to the hood and check things out eventhough everything was working great. This is what I found:

The stud had sheared off roughly 1/8" below the surface of the head. Ok, no biggie. So I drilled a hole in the remaining peice and tried a helical extractor (EZout). The extractor ended up shearing off in the stud... :rattle:Upon closer inspection of the broken stud, it looks like it was improperly manufactured due the "grainy" appearance of the fracture surface. If the stud broke due to being overloaded or sheared by the manifold it would have had a smooth surface.

So after some hard head-to-wall knock outs, I regained my chi and decided to order a new head. After looking at the options, I decided to try out the new 0331 casting everyone's been talking about instead of getting my 0630 rebuilt. This way I could run the MLS manifold gasket as well as get the strongest casting out there. The only downside is the smaller exhaust ports but with a turbo it's not much of a concern.

I ordered the head from J&C off Ebay and it came quick and in perfect shape. Since I couldn't really find a good review of the head, I decided to take some time and look it over as well as snap some pics to share. Overall I was really impressed with the quality of the casting and machine work. The casting is much nicer compared to my factory head, and is indeed thicker in several key areas. There is no roughness in any of the ports and no signs of mold deterioration. The combustion chambers all look the same and I'm sure would CC within a resectable range. The only work I did was to deburr the sharp edges to help fight against preignition. The exhaust valves are stainless and should hold up just fine to the heat.

Center web of my old 0630 compared to the new casting:

Intake Ports. Notice the smooth walls

Exhaust Ports:

 

[derrickdrew17]

Hmm... well good luck on that Head with its casting numbers. Unless its made by some one else other than who Chrysler got theirs from lol, They are known to crack

 

[Boostwerks.com]

I tore everything back down and cleaned up the deck surfaces. Thankfully the pistons and cylinder walls all looked great.

While I was in there I also checked the lifters to see if any were stuck or had unusual wear. I was honestly surprised to see that all 12 lifters we're in perfect shape with absolutely no signs of lobe wear. Obviously I will continue to use the high zinc amsoil I have been running.

I upgraded to the VR MLS gasket while I was at it. Before I threw it on, I gave it a couple shots of copper coat. This has been something I've always done when building motors as it helps prevent hot spots and fills small imperfections in the head and block surfaces.

Back on with new head bolts and all ARP manifold studs. I had also thought about going with ARP head studs while I was in there, but opted for the bolts since I won't be pushing the stock bottom end any further than I already have.

I forgot to get a completed picture, but I finished everything up last weekend and everythings been doing fine. I havn't noticed any difference in spool up, but I have noticed a good increase in low end torque due to the slight bump in compression. All in all, it sucked another $800 from my wallet but at least it turned out to be an upgrade. J.E.E.P.

 

[Boostwerks.com]

Hmm... well good luck on that Head with its casting numbers. Unless its made by some one else other than who Chrysler got theirs from lol, They are known to crack

please read :kissyou: This is an aftermarket replacement 0331 casting head. It does not have the 0331 #'s.

 

[derrickdrew17]

please read :kissyou: This is an aftermarket replacement 0331 casting head. It does not have the 0331 #'s.

Ahh got ya... well sweet setup IMO

 

[merdock69]

Just thought I'd mention that if you're thinking about doing the exhaust stud replacement along with a gibson header then you need to make sure and get a slightly shorter stud for at least the #4 (front to back) lower stud to ensure it clears the primary and you're able to get the washer and nut on after the manifold is in place. Otherwise you'll have the pull the manifold off slightly to slip them on and will end up having to use an open end wrench to tighten it (ask me how I know.)

I used the copper RTV & anerobic sealer on my intake and exhaust manifolds as well and it has worked well so far.

 

[merdock69]

Boostwerks, did you end up not going back with the copper RTV and anerobic flange sealer when you re-assembled? I notice in these new pictures you have a metal plate gasket. If you did switch, I'm curious why and what you went with this last time.

Thanks,