J10Mike

Again, more pics...

J10Mike

Pic modified down pipe.. And, still not finished with the upgrade.

oliver foster

Watching along here...
What sort of gearing are you running with those 35 inch tires?

J10Mike

Running 4.10s. Thanks.

J10Mike

Almost finished. Just need to clamp down the down pipe and modify exhaust.

J10Mike

All done. I guess I better get the good beer for the exhaust guy. Because, that weld job he did on the down pipe was right on the money. It mated up with the rest of the exhaust system perfectly. I can't ask for a better fit. And, even with the heat shield, I have just more than an inch of clearance from the firewall.
I haven't driven it yet. Got a family function to go to tonight and have to get cleaned up. Will take it out for a spin tomorrow.

oliver foster

Nice!
I like the cut down 6 BT exhaust manifold you have been running as well. If I was to do a 4 BT swap I would do the same trick on the manifold.
Another vote for the good beer for the exhaust guy.

J10Mike

Yep, that guy is getting some good beer.

J10Mike

Drive test completed and it appears the turbo upgrade was successful. It does seem to have more pep. Boost level went from max 12 psi (H1C) to 22 psi (Super HX30w). I'll push it again to see if boost will go higher.
And, here's the interesting thing. EGTs went from 1100 * at 70 MPH (H1C) to between 1000* & 1050* at 70 MPH (Super HX30w). It didn't hit 1100* until I got up to 75 MPH. Before and after tests were on the same stretch of level highway.
And yes, I did remove the silencer ring. So, it's a whistlin'
I'm a happy guy on Father's Day.

J10Mike

Well, after checking out all kinds of intercoolers online, I stumbled upon what I was looking for. A 1st gen Dodge CTD intercooler. When I bought the down pipe from a local guy a few months back, his parting words were, "give me a call if you need any other parts".
So, I sent him a text Friday morning. He had a good 1st gen intercooler and all the piping laying around for a very reasonable price. I didn't hesitate...I picked it up Saturday.

So, now I'm curious to know if anybody here has modified their 70s Dodge truck core support to fit a Dodge 1st gen intercooler?

Mike

J10Mike

OMG...My 4bt gots some power now. It's hard to believe it's the same engine. I turned up the VE pump...Adjusted fuel pin to steepest facing front of vehicle. Turned star wheel 2 full turns clockwise. And, turned up fuel screw 1.5 turns. I did not touch the smoke screw. That sure did wake up the Super HX30w. Just unbelievable performance increase.

I got home from the test drive, pulled into the garage, and thought...I'm not done. So, I took it out for another spin. It's really fun to drive now. Especially with the top off.

As for statistics...Boost still only maxed out at 23 PSI. EGTs were 1050* at 65 MPH, 1100* at 70 MPH, and 1150* at 75 MPH. That's on the same stretch of level highway as before. Unfortunately, it looks like that intercooler will be needed. Chugging up some steep grades with a heavy foot brought the EGTs up close to 1400*. I backed off the throttle a little bit to get it below 1300*. So, the intercooler is the next upgrade. But, what was good is that before the turbo upgrade, I would have to drop down to 2nd gear to get up those same steep grades. Now, I went up those grades in Drive and the speed was still increasing.

I'm definitely very happy with this turbo upgrade and turning up the VE pump.

oliver foster

Great to hear!
That 1st gen intercooler should be easy to fit behind a '70 grill.
I have seen the much bigger 2nd gen intercooler fit behind the '70s grilles [other than the 77 and 78 grilles] with the large turn signals that would interfere with the intercooler itself.

I tried to mock up the 2nd gen intercooler with my '78 grill for my 2wd 12V RC build. Getting the grille over it would require heavy cutting and re-working to the back of those turn signals.

J10Mike

Thanks Oliver. While I'm modifying the core support for the IC, I do want to rework the Intrepid electric fans to get the fan shroud closer to the radiator. Also, remove the a/c condenser since it doesn't have a/c anymore, making more room for the IC.
Move the Temp sending unit to the rear of the 4bt, and move the electric fan sensor to the fitting vacated by the Temp sending unit.
I just want to make sure I'm getting an accurate reading for the Temp gauge and the right temp to activate the electric fans.
Maybe some day, I'll be finished...

J10Mike

Took a long road trip in the RC over this weekend. Finally, some real hand calculated MPG numbers using GPS speedometer/tripometer. 90% highway doing 65 to 70 MPH.

4bt, 46rh, 4.10s, on 35s. 19.25 MPG.

I was hoping for at least 20 MPG. But, close enough. Maybe had I had 3.54 gearing. Oh well.

At least it's better than the 9 MPG I was getting with the old 360.

J10Mike

Received the new M3 fuel pin today and it took all of about 8 minutes to get it installed. Took it for a spin. Again, what another positive difference in performance. I believe I chirped the rear tires going from 1st to 2nd gear. I actually didn't hear a chirp. I just felt the loss of traction during the shift. The new Super HX30w turbo spools that quickly now. I still can't believe the power I'm getting out of this 4 cylinder diesel engine. It's like decent V8 power. Of course, not as quick as my Hemi Charger. But, nice power for a 41 year old 4bt powered truck.
I wonder what the HP and torque has increased to.

In the pic, stock fuel pin on the left. New M3 fuel pin on the right.

While I was at it, I also replaced the squeaking belt tensioner tonight as well. No more squeaks...