Forced upgrades

The past week or so I've been upgrading the lung capacity of my `70 Chevy pickup. This was necessitated by essentially destroying the original Rochester 2GV carburetor when I stripped out the jets in the upper housing. So if anyone needs a Rochester 2GV for parts let me know. The air cleaner, linkages, lower housing, etc. are in great shape. Heck you can even get the original cast iron intake manifold.

I didn't immediately give up on the original 2 barrel. But after a few days of Googling for a HeliCoil kit to repair the 1/4-32 threads I resigned to the fact that I'd have to order a new carb. I debated over whether to get another Rochester 2 barrel or upgrade to a 4 barrel. I liked the idea of a Rochester Quadrajet topping a 307, just like when I was 16 driving a 1983 Oldsmobile Delta 88.

This picture was taken before we donated the old girl to the Stafford High School Auto Shop. Keep in mind this picture was taken after my sister and brothers had ridden that poor Olds hard and put it up wet. But those stories are for another time...

Going the Rochester Quadrajet route proved to be expensive so I settled on an intake/carburetor combo from Summit Racing. It included:
  • Edelbrock 2101 aluminum intake
  • Edelbrock 1405 four barrel carburetor
  • Summit Racing air cleaner
  • Adapter plate and various hardware
In a few days all kinds of boxes arrived on my doorstep containing testosterone drenched performance parts. I immediately went to work removing the carburetor, distributor, coil, and the original intake. Here you can see the original cast iron unit in that gorgeous Chevy orange.

Next we drained the radiator to remove the upper radiator hose. Here the intake has been removed, revealing the valley of lifters.

Nothing left to do but scrape the old gasket surfaces and install the new one.

All was going smoothly until I stripped the holes for the thermostat housing. Do we see a pattern developing? Yes, I am using a torque wrench. Unfortunately I was using the shop manual that assumes a cast iron intake. I guess aluminum just won't tolerate 25 ft-lbs. No problem, I have some HeliCoils that will make it stronger than bare aluminum. Since I have no torques specs for aluminum I'll just cut the cast iron values in half. That ought to work right? Wrong. The Helicoils cut those fresh threads out. Dang, now I need a new intake.

The next day I called Summit Racing while waiting for Vista to finish an upgrade. The good people at Summit Racing said they'd ship one out that day. All I had to do was box up the damaged intake and wait for UPS to pick it up. Sweet! We're back in the game!

OK, note to self, only hand tight on the thermostat housing and use high temp RTV on both sides of the gasket. The next photo shows the Edelbrock 1405 sitting on top of the new intake. Yep, I opted for the electronic choke kit. Pray for no leaks!

Well that was too much to ask for. The thread sealant on the heater hose outlet wasn't holding up. And I'm not torquing it down any tighter! Time to drain the radiator and replace the thread sealer with teflon tape, lots of it.

The several wraps of teflon tape are holding up and the 307 is purring like a kitten. Now I just need to fabricate a new throttle rod assembly. The original was 1/4 inch and the Edelbrock is 1/2 inch. After a few minutes Googling I came upon a Ford enthusiast site that describes how to build your own. Time to order more parts and wait for the big brown truck.

Following's plans I built my own, and I must say it is pretty freakin cool. See for yourself.

So after many trips to auto parts and hardware stores and the internet I finally have a four barrel carburetor that can really feed those Hooker Super Comp headers.

There are still a few miscellaneous items to finish but I'm too busy test driving.


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