1990 Dodge D50 (Mighty Max) 2.4L 2WD Project

poorboyj · Post by **poorboyj** » Sun Jan 16, 2005 3:27 pm

This is a long overdue post. I’m not sure if this is DSM Tech, Fabrication, or Other Vehicle Tech (Mod’s feel free to move this). I got this truck Jan. 2004; it always smoked due to a cracked head. Finally, April 2004, I decided to replace the head with a 4G63 head and ECU, at the same time, add a 20G turbo and limited slip rear differential. Project was completed and drivable Jan. 2, 2005.

Bolting the 4G63 head on the 4G64 block was the most straight forward part of this project. I used a 1994 Galant head gasket and timing belt, with DSM head bolts. Some of the problems I encountered were thermostat housing relocation to the front of the head, DSM front case and timing gears (since the Galant & DSM belt is wider than the truck’s original SOHC belt), relocation of the throttle body to the “other” side of the cyclone manifold, swapping fuel feed and return on rail, and of course splicing the DSM ECU into the truck’s harness.

A note on wiring: If I had to do this again, I would just ditch the stock truck harness and use a complete DSM harness. But, I do appreciate the experience of learning the ins and outs of the DSM EFI system I gained from this.

Here are a few pictures of this burnout machine. Next items are to replace the fuel pump with a Denso (drop in? maybe, maybe not), mount the power steering pump, and replace the now slipping clutch. You’ll see this thing at Norwalk, August 2005 (possibly for sale).

<a href='http://www.v8eaters.com/uploaded/jays/turbotruck219.JPG' target='_blank'>http://www.v8eaters.com/uploaded/jays/t ... 219.JPG</a>
<a href='http://www.v8eaters.com/uploaded/jays/turbotruck054.JPG' target='_blank'>http://www.v8eaters.com/uploaded/jays/t ... 054.JPG</a>
<a href='http://www.v8eaters.com/uploaded/jays/turbotruck127.JPG' target='_blank'>http://www.v8eaters.com/uploaded/jays/t ... 127.JPG</a>
Front Mounted Water Outlet - Not the most effecient, but what could I do?!
<a href='http://www.v8eaters.com/uploaded/jays/turbotruck052.jpg' target='_blank'>http://www.v8eaters.com/uploaded/jays/t ... 052.jpg</a>
<a href='http://www.v8eaters.com/uploaded/jays/t ... let086.JPG' target='_blank'>http://www.v8eaters.com/uploaded/jays/t ... 086.JPG</a>
<a href='http://www.v8eaters.com/uploaded/jays/turbotruck151.JPG' target='_blank'>http://www.v8eaters.com/uploaded/jays/t ... 151.JPG</a>

Jay

Mike · Post by **Mike** » Sun Jan 16, 2005 11:42 pm

How much boost are you planning to run on the stock internals? I have a 93 Mighty Max with a 90 block, balancer shafts eliminated, new belt, tensioner, gaskets, DXD clutch and pressure plate, machined flywheel, new pilot bearing and throwout bearing. I almost had the transmission in when I realized I installed the clutch fork backwards, and without enough clearance to punch out the pins to remove it. When I finally get this completed there is going to be one hell of a peg leg in front of my work.

Post by **DJpowerHaus** » Mon Jan 17, 2005 5:39 pm

Wow... both 90 blocks. I got the same 2.4 block .. same year from WickedTSI. poorboyj... I saw this truck on DSMtuners I think. Its pretty neat. If you want to make a write up of this thing I'd love to put it on the site. I actually have another persons build up that I need to post already. I've really been getting behind on the site.

Mike.. what do you think of that DXD clutch? I love mine. How'd you find out about them?

Mike · Post by **Mike** » Mon Jan 17, 2005 11:44 pm

You recommended it to me, remember? Anyways I should find out how I like it Wednesday. The six puck clutch disk looks aggressive. Also a couple friends want to race when I'm done: a 1.6L Miata and an S14, both stock. I think I can take the Miata at least. I have a lot of free time between now and Wednesday to make a few modifications...

Mike · Post by **Mike** » Thu Jan 20, 2005 1:54 am

I'm have some problems with the flywheel. The motor I bought was originally out of an automatic and used a spacer with longer bolts between the flywheel and the crankshaft. Well I couldn't use the automatic flywheel, so the yard gave me a manual 6 bolt flywheel that supposedly works, but I didn't ask what it came from. I tried eliminating the spacer and but when you tighten down the flywheel, the engine will not turn over. So I put the spacer back in but now I had to use the automatic flywheel bolts which are longer. Well, they don't seem to be long enough as I found out by stripping the threads off of two of them. It seems the flywheel given to me has a different offset than what I'm supposed to have. If I use longer bolts, will the the transmission still fit it? Anyone run into this problem?

poorboyj · Post by **poorboyj** » Fri Jan 21, 2005 8:50 am

Guys,
I am having a hard to visualizing this cam gear thing. Does anyone have a picture showing the differences between the Galant DOHC cam gears and DSM ones? I’d like to use what I have, so where should the new marks go? I am thinking both the cams need retarded (counterclockwise) 1 tooth. Is this correct?

Thanks,
Jay White

peregrine · Post by **peregrine** » Fri Jan 21, 2005 7:02 pm

that thermostat housing is a great idea for a race car but for a street driven vehicle you really want to have crossflow through the head. if i were you i would get ready for overheating problems and a warped head. im currently working on a low profile adaptor that you can use a thermostat with. i just need to cut my stock housing so i can have a template and im procrastinating on that one

Mike · Post by **Mike** » Sat Jan 22, 2005 2:33 am

I solved the flywheel problem. Today I noticed that the driveplate on the back of the engine is about twice as thick on the autos as the manual. So I swapped on the manual drive plate and the engine turned like butter.

Should be able to drive it tonight.

Mike · Post by **Mike** » Fri Jan 28, 2005 2:04 am

A few questions about the truck poorboyj.

What LSD did you use, a 4x4? Front or rear? How did that go? Did you see if it was also possible to swap hubs with discs?

How about the instrument cluster, does that work with the DSM ECU? What about the knock sensor?

I assume you have the sport model with a tach, power steering, bucket seats, right? How's the steering? I have the manual rack and it feels like a boat compared to the DSM.

For DJ: I've been using the truck as my daily driver since Monday and the clutch feels great. At first it felt like my slipping DSM clutch, but I just had to make some adjustments to the cable and it was fine. Although there's not a whole lot of room for adjustment, I was almost all the way to the firewall. There is a small amount of chatter when engaging at idle speed, but I assume that's normal for a six puck. Probably have to adjust it again in a week after I break it in.

poorboyj · Post by **poorboyj** » Fri Jan 28, 2005 11:13 am

</div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (Mike @ Jan 28 2005, 07:04 AM)</td></tr><tr><td id='QUOTE'> A few questions about the truck poorboyj.

What LSD did you use, a 4x4? Front or rear? How did that go? Did you see if it was also possible to swap hubs with discs?

How about the instrument cluster, does that work with the DSM ECU? What about the knock sensor?

I assume you have the sport model with a tach, power steering, bucket seats, right? How's the steering? I have the manual rack and it feels like a boat compared to the DSM. [/quote]
I actually got this LSD on Ebay. It says 1988 Dakota/D50 Posi on the side with a paint marker. The install went beautifully, a straight up swap, about 2 hours with bleeding the brakes. I don't know about a rear disc swap, it can't really be a big deal on a truck.

Since I left the truck harness in place and just spliced in/added the DSM wires & sensors, the instrument cluster works, but I have no tach, and I need to find out why. There is a provision for the knock sensor on the side of the block.

Yes, I have the SE model. I have the power steering pump still in the engine bay, but I need to find a way to get it bolted up and working again. No PS sucks, especially when you still have the power rack and everything. Work in progress.

I will caution you guys, I believe my compression ratio is close to 12:1. A big miscalculation/over-look on my part. I get part throttle knock on 93 octane. I'm going to try a few things with timing and fuel, but static compression was 260 psi!!!

Jay

Mike · Post by **Mike** » Fri Jan 28, 2005 4:01 pm

Not sure if this will help you or not, but while researching how to swap an instrument cluster into my truck, there is a noise filter on the passenger firewall that is supposed to suppress needle spikes and such. Maybe the DSM tach works on a different frequency, and the filter is blocking it out? Try disconnecting the filter and hooking the tach up directly and see if it works. The tach will work without the filter.

Sounds like a race gas engine. You're going to need a set of pistons from what I can tell, and if you're going to go that far, you might as well do a complete build.

Post by **DJpowerHaus** » Sat Jan 29, 2005 11:33 pm

I knew a honda guy that went turbo and used 2 head gaskets on top of each other to lower the compression.

Mike · Post by **Mike** » Sun Jan 30, 2005 4:12 pm

That sounds like you could blow the gaskets real easy that way. You can buy thicker metal headgaskets and also modify clearances on the head, but I still don't think you'd end up being able to run 93 octane. You need about 8.5:1 compression for that.

poorboyj · Post by **poorboyj** » Tue Feb 01, 2005 2:26 pm

Well, according to my latest calculations, I'd need a .180" thick head gasket to get to get to 8.5:1. Any of you guys have exerience with water/meth injection? Would it get me close to where I want to be?

Thanks,
Jay

Post by **DJpowerHaus** » Tue Feb 01, 2005 5:12 pm

That's probably something better posted on DSM boards. Maybe some rally guys have tried it. Try the www.specialstage.com forums.

Mike · Post by **Mike** » Wed Feb 02, 2005 1:45 pm

I hear you can obtain cometic gaskets an any size you specify. For reference, a stock head gasket has a thickness of .054.