94 SR 3.8 DOHC Project

[Toasty]

This is super cool, I never did find that oil pan. I'll ask Kevin for you, I suspect it went on another engine just to cover a bottom end.

 

[Justice R]

This is super cool, I never did find that oil pan. I'll ask Kevin for you, I suspect it went on another engine just to cover a bottom end.

Thanks for lookin, it’s the last piece to the puzzle needed (I think)

 

[Justice R]

Ordered a bunch of parts and working on the heads in the meantime. All the valves in the SR heads were bent, so I ordered new valves and been lapping them in. One head done so far with another to go.





looks like I’ll need to grind out the thermostat housing port to match the SR water pipe upper connector the SOHC one interferes with the inner cam sprocket and points the radiator hose too far to the rear. Shouldn’t be too difficult.




going to use the updated larger oil hole lifters. Still need to clean them good and do the testing per the FSM.



everything looks really good on the bottom end so I’ll probably run it as is. It needs A good cleaning and some fresh paint.



Still need to figure out the oil pan, maybe go down to El Paso and see if we can find one down there with the smaller front saddle.

 

[CharlieNorth]

I need to refresh my memory but I think I am running the DOHC waterpump. I did not need to rework the outlet on top. I recall making a change to one radiator hose neck, welding involved but that would be due to the large aluminum radiator I run.

 

[Justice R]

I need to refresh my memory but I think I am running the DOHC waterpump. I did not need to rework the outlet on top. I recall making a change to one radiator hose neck, welding involved but that would be due to the large aluminum radiator I run.

I was hoping that the DOHC water pump would fit, but it wont. The holes in the block are a bit different and the bolt pattern on the ends near the ears of the pump slant differently. I’ll have to post a pic of them side by side.

 

[CharlieNorth]

I just spent some time in ASA parts book, There is early and late on the SR engine, but the later PN particularly the gasket shows interchange on most every V6.
We have dinner guests just arriving in their hellcat.

 

[Justice R]

I just spent some time in ASA parts book, There is early and late on the SR engine, but the later PN particularly the gasket shows interchange on most every V6.
We have dinner guests just arriving in there hellcat.

Yea, I took a second look last night, they definitely won’t interchange on this one. The bolt pattern is different and the back half is different in that it is in two pieces on the 94 SR while the newer pump back half is in one piece. The flange where the pump turns the port towards the front is smaller as well. This one is a 94 so it’s definitely an early DOHC. Maybe I need to go back to the junkyard and look at the 96 sr pump back half …

 

[Justice R]

Here’s the new style pump vs the old off the 94 SR.


you can see the old style is a little wider and bolt pattern difference. Also the port is different and slants to the left a little. Going to go see if we can get the correct parts off the 96 in the yard here in a bit.

 

[CharlieNorth]

Looks like a SOHC pump, books show 94 up to be the same, but I also see anomalies in the books

 

[Justice R]

Spent some time in the yard today, 96 SR pump was the same as the 94 SR. Not sure what the Missing link is. Tore the thermostat housing off a 3.5 SOHC gen 3 As well as I could see that it also has a two piece water pump back like the DOHC. l just took the gasket to check bolt pattern since I didn’t feel like removing the fan and all accessories to get the pump out. Checked when we got home and Gasket appears not to fit DOHC water pump back either, so looks like I’ll need to break out the die grinder.

 

[Justice R]

Looks like a SOHC pump, books show 94 up to be the same, but I also see anomalies in the books

Yes, the one on the left is the SOHC pump, which is the one that fit’s to the 3.8 block. Maybe there’s a magic back half that fits both the SOHC pump and DOHC thermostat housing assembly, but I can’t seem to find one. Even tried a KIA 3.5 DOHC.

 

[CharlieNorth]

Are you talking about mounting the pump to the block or the thermostat to the pump?

 

[Justice R]

Are you talking about mounting the pump to the block or the thermostat to the pump?

Both. The SOHC pump is the one that will mount to the 3.8 block. None of the DOHC thermostat housing parts will fit to the SOHC pump back half. The SOHC thermostat housing needs to be adapted to the DOHC water pipe as the SOHC pipe interferes with the cam sprocket. Shouldnt be too hard to adapt it one way or another as they are close. I’m going to move on and tackle that once I get the heads back on the block. Got one head ready and still need to reassemble the other one.

 

[Justice R]

We made some good progress here lately.

One of the valve covers looked like it had been eaten away by something caustic, I tried to buff it out with a wire wheel but it still looked booty. Couldn't handle looking at it so we pulled one off the 96 SR in the pick n pull. It was filthy but was nice once all the grease came off




new one is a lot better








wife pulling a thermostat housing off a gen 3 in the yard, it didn’t fit the 3.8 water pump though.


the block is cleaned up with a fresh coat of paint. Water and oil pumps are installed. The heads are just sitting here on the block for now. One more cleaning and they’ll get torqued down with new head bolts.

 

[CharlieNorth]

I just went through my photos from my DOHC swap and I used the full G2 SR waterpump, thermostat and piping. My build utilized an aftermarket all aluminum crossflow radiator as most all my swaps have.
If I recall I made minor changes to a radiator hose outlet to suit the change in radiator.
I have very few pictures of the work since it was done before I discovered the Wire.