Our SBB 300

Discussion in 'Small Block Tech' started by MarkusM, Oct 20, 2018.

  1. MarkusM

    MarkusM Active Member

    OK, this is a stock 300 in a Chevrolet Corvair Truck as mid engine. The Trans is a ST400.
    I only adjusted the timing a bit for better idle and starting. The carb is a Rochester 2GC from a 66-67 Pontiac.

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    We bought a 1964 300 engine with aluminium heads and intake to save some weight on the front suspension. So in the next weeks I plan to take the 1964 engine apart, the pre owner told us that that one rod is damaged.
    I will check the heads and 2bbl intake, maybe do some porting. We get the original 1964 carb with it so we will use this one. I want to learn more about the Rochester 2bbl, so I will take the Pontiac version apart, clean it and see what tuning options I have.

    I have a AED 650 HO carb on my Chevy. I changed the high speed air bleeds (I cut a thread in to do this), idle air bleeds, changed the main jets and idle feed restrictor too. I'm using an Innovate O2 sensor on our cars for tuning.
    So I want to use it to tune the 300 too.

    I also want to change the distributor from stock points to electronic. I also have experience in recurving the timing.
     
    Last edited: Oct 21, 2018
    Dano likes this.
  2. MarkusM

    MarkusM Active Member

    More pics

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  3. MarkusM

    MarkusM Active Member

    I found the engine code. LL = 1965 std engine. After getting the headers off I found the code. By the way there was no gasket between headers and head.

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  4. ssmock

    ssmock Well-Known Member

    The 300 engine in 64 had water choke Rochester crabs, both 2 and 4 barrel. At least on the Skylark and Specials. A one year only system along with the aluminum intake and heads. Guess that system didn't work so well. I did change to a single wire Electric Limited points conversion kit about two years ago with no problems. Works well.
    Would be interested in what options you find on tuning / improving the Rochester 2bbl crabs.
     
  5. DEADMANSCURVE

    DEADMANSCURVE my first word : truck

    cool . appreciate the way different approach . how's about a few pics of the overall project - exterior , etc .
    yeah i was gonna say that kinda looks like a '65 motor ? if so better except for the weight - IMO .
    if any questions , ask away . sorta the measure twice , cut once rule .
     
  6. MarkusM

    MarkusM Active Member

    http://www.v8buick.com/index.php?threads/hi-from-germany.339073/ here you go.
     
  7. Jim Blackwood

    Jim Blackwood Well-Known Member

    I just bought the '67 version of that engine. It's a good candidate for an engine swap into an MGB and easily puts that car into Muscle car territory since the vehicle weight with it can be at 2500 lbs or less. The engine fits easily, later cars were designed for the Rover version of the 215 and the hood will close on it if properly done. Plus things like bellhousings are easier to find and cheaper. Reliability and engine life is way better than any of the Rovers or 215s and headers are an off-the-shelf item.

    You wouldn't normally go looking for a 2bbl engine of course, but here again there are advantages. Because the CR is 9:1 it can burn regular and get reasonable economy. Or it is a good candidate for forced induction (not much room for a turbo though). Or, a head swap can bump it up to something in the 11-11.5 range depending on head gaskets. Of course there you take a hit on the valve and runner size unless you go with the TA Rover heads but even so the 4.6L Rover heads aren't horrendous, just 2 steps down from what's on there already. Realistically the power would probably stay about the same but the weight would go down.

    So speaking of weight. The iron heads weigh 52.5 lbs more than the aluminum ones. I've not pulled the intake yet but let's say that adds another 25 lbs or so, give it a round number of 75. The 300 with alloy heads and intake weighs 50 lbs more than the stock 4 cylinder engine that the car comes with, and the car will easily accommodate an extra hundred pounds on the front end, we proved that with the 455 swap. So what I'm saying is that where the desirable thing with a Skylark is to pull the 300 and install a 350 or a 455, one of the best uses for the old 300 is to put it in a late model (rubber bumper) MGB. It's pretty much a perfect match.

    Jim
     
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  8. MarkusM

    MarkusM Active Member

    Good Information.
    The Corvair Rampside truck was an rear engine version like Porsche or VW Van. So the front end was never constructed for the weight of an engine.
    But in the late 60's and early 70' some Hot Rodders used this front end in Hot Rods, so there are better bushings and coil springs available. Shocks are the same like in my 55 Chevy, so there are good performance shocks available.

    The plan was to save weight with the aluminium parts, than rebuilding the front end so it can handle the weight of the engine.
    The engine is very high mounted in the rails and front crossmember, I will made new mounts to mount the engine lower.
     
  9. OddfireV6

    OddfireV6 Active Member

    Somebody put a Buick V8 in a Corvair. I find that hilarious.
     
  10. Jim Blackwood

    Jim Blackwood Well-Known Member

    Actually not all that uncommon back in the day. The 215 was a favorite for Corvairs and VW bugs due to the light weight. In my home town of 2500 there was a guy with a 215 Bug. He needed wheelie bars on it. Pretty wild to see him leaving the high school lot headed down Main St with the bumper dragging the ground. Midships SBC Corvair conversions were popular too.

    Jim
     
  11. MarkusM

    MarkusM Active Member

    We got a 1964 300 with aluminium heads and 2bbl intake.

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    I disassembled the engine.

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    When I got the valves out they looked like this.

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    I cleaned them up a bit.

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  12. Jim Blackwood

    Jim Blackwood Well-Known Member

    That's a pretty good find. 9:1 CR which is decent enough, will run well on a big 2bbl. 4bbl intakes are still around. Excellent candidate for forced induction. How's the valve stem clearance?

    Jim
     
  13. MarkusM

    MarkusM Active Member

    I removed the markings to get a smooth surface
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    Next step is to clean the head and get the valves back in.
     
  14. MarkusM

    MarkusM Active Member

    I started cleaning the heads, it is work in progress.
    I'm waiting for the header flange to port match these two parts.
    Maybe I will do a port match on the intake side too.
    There was much carbon everywhere and you can see some very small rough spots.

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  15. MarkusM

    MarkusM Active Member

    Intake port matching

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  16. 64 skylark mike

    64 skylark mike Well-Known Member

    Looks like your 64 engine came out of an A/C car. Corvair pickup looks cool!

    My wife had a '64 Corvair Monza convertible when we got married, fun little car. Good luck with your project.

    My '64 Skylark had a 300 2bbl in it when I got it. I rebuilt the carb once, seemed pretty simple as I remember, got a rebuild kit from NAPA.
     

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