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89 RAM 50 4g swap "Validation Plan"

PLDSM

Proven Member
306
295
Dec 8, 2013
Warren, Michigan
WOW.. just wow.. I think this is one of the best truck builds ive seen.. I have a few questions... what rear wheel size did u go with? what was the 8.8 out of and how much did u cut off to narrow it? im building a 86 MM with just a small 4g61T. evo 3 16g setup..I also have a 8.8 from a 87 t-bird. cant wait to see the numbers on this beast..
If I remember correctly I cut off 2 7/8 from the driver side in order to be able to use the same axle shaft that was on the passenger side.

Axle came out a ford explore sport. Diff cover from an explorer as well however earlier 2000's when they went to a irda style diff. Can find them in any local junk yards. Just rear the tag on the diff cover to see 8.8, 3.73 lsd. To get correct pinion angle you will need to cut the old perches off the axles and weld new ones on. You can make your own if you have access to steel or a good place to buy from is ruff stuff specialties.

Wheels are from summit. 15x8, 5.5" backspacing. Tires are 275/50/15 nitto nt555r II's.

Good luck with your build. If you ever have questions just pm me.
 

PLDSM

Proven Member
306
295
Dec 8, 2013
Warren, Michigan
Dyno day!

Well as fast as it was put up on the dyno it was taken off the same time. Drove the truck handful of times with decent load all around the city and even to the dyno facility. As soon as the truck was strapped in and ready for some pulls it started to overheating when trying to do WOT pulls. Tried a couple things to see if it made any difference on the rollers but sadly nothing helped. (Burped coolant again and again, took out thermostat to rule out being stuck, turned on the interior cab heater and roasted my ass off in the truck(core not clogged)), stacked a ton of fans in front of the truck (too bad there is a big ass intercooler giving a little restriction). Not much more could be done so I drove it home, never got over 200 degrees driving home but for some strange reason in the shop it would run hot at idle and even hotter with load.

To do:
For sure going to run a compression test and leakdown test (no coolant or oil mixing seen in either resivour or pan), possibly the China pay half rad is no good or fan not flowing enough cfms??. If boost and leakdown test don't show negative results then I will try to swap to a better name brand radiator and fan setup I can pull off one of my other cars and go from there.

I can see coolant flow so I can easily rule out the water pump being the culprit.

Headgasket? I sure as hell hope not. Doesn't burn any coolant, no loss of coolant in resivour and no mixing but I guess leakdown should point us in the right direction.

Stay tuned for what's to come.

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mattp_65

Supporting Member
507
153
Aug 16, 2004
Granite Falls, Washington
I think I had similar issues with my Ebay half rad on my 4G63LUV. But it would run hot with load of any kind so I swapped to a late 60s mustang radiator.
I dont think I shared on my thread that I swapped radiators (I dont know why LOL). https://www.dsmtuners.com/threads/78-chevy-luv-build-w-4g63t.513590/page-2
But here I had the small half rad and on page 3 I have the bigger and more efficient mustang rad.
Get a bigger rad and you should be fine. Great build btw!
 

PLDSM

Proven Member
306
295
Dec 8, 2013
Warren, Michigan
I think I had similar issues with my Ebay half rad on my 4G63LUV. But it would run hot with load of any kind so I swapped to a late 60s mustang radiator.
I dont think I shared on my thread that I swapped radiators (I dont know why LOL). https://www.dsmtuners.com/threads/78-chevy-luv-build-w-4g63t.513590/page-2
But here I had the small half rad and on page 3 I have the bigger and more efficient mustang rad.
Get a bigger rad and you should be fine. Great build btw!
Thanks for the input! That's the route I was thinking of going. Before I did the full build I had a sbc radiator and it never went over 190, ever since the switch it has just been giving me issues. Worst part is the way i did the intercooler piping and how the intake manifold sits i can only get away with x amount of space for a radiator. Makes me feel better that you chimed in because I always expect the worst.

Love your build man! Very unique.
 

Mech Addict

Supporting Member
1,104
511
Jun 9, 2019
Jackson, Wyoming
Frustrating time for a setback, that's for sure. Hot at idle is a what makes me agree with PLDSM; radiator (and/or fan) is not shedding enough heat. It shouldn't have been generating more than a stock motor below 1,000 rpm. I guess the shop didn't want you to run a garden hose over the radiator while making pulls.
 

PLDSM

Proven Member
306
295
Dec 8, 2013
Warren, Michigan
Frustrating time for a setback, that's for sure. Hot at idle is a what makes me agree with PLDSM; radiator (and/or fan) is not shedding enough heat. It shouldn't have been generating more than a stock motor below 1,000 rpm. I guess the shop didn't want you to run a garden hose over the radiator while making pulls.
Haha, yea definitely not an approved process at they dyno facility. I'm going to play around to see if the mishimoto half rad works with the derale fan. This is more to test the theory of if there are any major Interna design differences for flow and heat exchange for future reference if not then will get a bigger one and modify the Intercooler routing and coolant routing.
 

PLDSM

Proven Member
306
295
Dec 8, 2013
Warren, Michigan
Got pretty tied up with work and the kids but the truck is back and ready for the dyno again. Got the new radiator and fan setup installed, new coolant pipe made, coil pack location changed and we figured we would swap out throttle bodies since the response of the old setup wasnt to our likings. Dyno day part 2 will be 10/11/22.

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PLDSM

Proven Member
306
295
Dec 8, 2013
Warren, Michigan
I like the Radiator! Also the coolant pipe, want to make me one too? :)
Mine was a cut down oem eclipse water pipe to make it fit ok.
Your suggestion worked and the radiator fit pretty well after I cut out the lower mount I made for the other half rad.

Sure, I don't mind. Send me a pm and we can work out the details. Replicating this one or even adding to it for your setup is easy.
 

mattp_65

Supporting Member
507
153
Aug 16, 2004
Granite Falls, Washington
Another suggestion if you want to get rid of a rad cap is to use a mid-90s hyundai sonata thermostat housing.
Part number from Dorman

902-5108​

I also used the hole to hold my Fan temp thermo switch to run my fans. Switch is set @ 180degs (down fall is can't be turned on manually by ECMLink).

1665005459624.png


Hard to tell...this is what it looks like
1665005756198.png
 

PLDSM

Proven Member
306
295
Dec 8, 2013
Warren, Michigan
Another suggestion if you want to get rid of a rad cap is to use a mid-90s hyundai sonata thermostat housing.
Part number from Dorman

902-5108​

I also used the hole to hold my Fan temp thermo switch to run my fans. Switch is set @ 180degs (down fall is can't be turned on manually by ECMLink).

View attachment 675439

Hard to tell...this is what it looks like
View attachment 675440

Very good suggestion and I appreciate it. I ended up using a higher pressure cap in the rear and a lower pressure cap on the radiator side just for this cause. I rather have it leak out at the radiator then at the back of the engine by the firewall. Original plan was to use a slim billet block but went against that since it would have deleted the thermostat.. don't have a thermostat in at the moment but that's a different topic LOL. The thermo housing your pointing out is a great way to remove having 2 rad caps and reducing another potential failure/leak path and I like it. Got to love the impact hyundai/Kia parts provide for dsms and evos.

I have a 190 thermo switch in my housing but I also tied in a toggle switch just in case the actual sensor fails. I'm on megasquirt so in the same boat with being able to power on certain features.
 

PLDSM

Proven Member
306
295
Dec 8, 2013
Warren, Michigan
Back to the dyno we went. Got some pretty good pulls in today, but with the good comes the bad.. As soon as we put the truck on the rollers the wideband sensor decided to die (good thing i brought a spare with me), then just as we started turning it up to a decent powerband the rear tail seal decided it did not want to hold the fluid in the trans anymore and started pouring out. But onto the good news. Truck made 490 to the rear tire at 21 lbs of boost. Very conservative timing on pump gas.

 

PLDSM

Proven Member
306
295
Dec 8, 2013
Warren, Michigan
If only it was as easy as a tailshaft seal..... got the truck back up on the wheel cribs and noticed that the tailshaft bushing pushed out based the seal.. never have I ever seen something like this.
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20221016_124014.jpg
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Was able to get the tailshaft housing off to assess why the bushing/bearing spun and pushed out past the seal.. didn't have much luck finding the exact replacement however the th350 one caught my eye since I am actually using that tailshaft seal.. so I may have to brake hone out the bore ever so slightly to get the new busing in.. more to come.

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PLDSM

Proven Member
306
295
Dec 8, 2013
Warren, Michigan
Got the tailshaft situation all buttoned up, ended up having to brake hone the new bushing in order to get the appropriate oil clearance to the yoke.

Mission eliminate crank case pressure is a go as well.. ended up getting a sealed catchcan setup for a super good deal. All that was left was to bend a bracket for the unit as well as weld on the fittings to the air intake.

20221031_201532.jpg
 

PLDSM

Proven Member
306
295
Dec 8, 2013
Warren, Michigan
Finally getting there.. got the idle all set up, megasquirt give us a he'll of antime with the idc setting, so let's just say we are not utilizing that function and truck still starts and drives great. Got into some shenanigans last night of us taking turns driving the truck which was a great feeling and also got the 2 step all set up on the conservative side.

 
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