The deed is done.
Gen III Vortec, 4.8 liter (LR4, drive by cable) motor is on the way (!).
Why? To get the truck where I want it, I'd need to convert to fuel injection, redo the entire pass. side of the exhaust, upgrade the alternator, and likely rebuild the lower end and heads (valve seals, at least).
If I'm going to that much trouble, I might as well get a newer, low-mileage motor as well.
This motor has 84,xxx miles, and is out of a 2001 Silverado.
The truck, as of last night:
Battery is out, radiator is out,etc...making progress in 30 minutes increments. Such is life.
...
As a reminder, here's where we are: '87 FJ60 with a carb'd Chevy 305 V8 swapped in...using a Ranger Overdrive as part of the drivetrain conversion.
The Chevy bellhousing will bolt up to a LSx based motor, minus one bolt (a non-issue).
The flywheel is .400" further set in on your average LSx motor, as compared to a SBC, but there's a Sachs flywheel that is thicker, and makes up the difference: Part # NFW1050 (cheap, too - $70)
Will have to redo the motor mounts. Easy stuff.
But, I'd appreciate some input on a few other swap considerations from those "in the know". I've done a fair amount of research elsewhere, but it's time to read here (I know there a few recent swap threads with part #'s, etc...)
- Fuel Pump: External, Airtex E2000 (apparently a common Ford replacement - Readily available in case of breakdown) I think that's a no-brainer. Will likely run an all new feed line (AN?), and use the current feed as my return line (this motor has the regulator on the rail).
- Pilot Bearing: A usual 'old school trans' (Muncie, etc...) behind a LSx motor can use a Chevrolet Performance pilot bearing (#12557583)...I'm hoping my Ranger box has a similar shaft diameter where the pilot bearing engages it. I can measure once the SBC is out.
- Radiator: Hoses will be custom, pieced together from the parts store. The stock fan clutch should fit, but I'll need to build a shroud (did not have one before anyway). I'll add a secondary e-fan as well for the A/C.
- A/C: Hoses will likely be custom (again), as the custom set in there now (adapting a '99 Suburban compressor to the factory A/C setup) will probably not work. We'll see. I'm going to reuse the compressor on the new motor (and it's located on the pass. side bottom of the motor...whereas the current compressor is on the drivers side top). Might upgrade the condenser to a newer style as well (parallel flow).
...
So, hopefully it comes together in the next couple months.
You might be thinking WHY a 4.8? Well, it's rated at 270hp/295tq...the SBC in there now is probably 200/250 (on a good day), and stock power is 135/200.
So it's a huge upgrade over stock, and the limited TQ might help ward off breakage if I get an angry right foot.
I couldn't see spending nearly twice as much for a 6.0...and even the 5.3's were another $500 or more....for not much gain, in this application.
Plus, I should get pretty decent fuel economy with the smaller motor (which is important, in remote places or long highway drives).
Also: Reliability is paramount here, so I'm going to use stuff available at your average parts store over custom or specialty parts...if possible. If I break down 500 miles from home, I want to be able to source parts.
OK, I'm rambling now.
I'll update more as I go.
Thanks for reading.
- Brian