Thread: What engine do I have?

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I'm a long time lurker, but I think I may never have posted before.

I recently bought a '32 Ford roadster. SBC/TH350 combo. I need to find out what engine is in this so I can decide where to go with hop up parts. I assume this started life as a simple 290HP 350 ci engine, but that's a blind assumption. It's got a Victor Jr intake manifold with what I believe to be a 650 Holly 4bbl. Block hugger headers, 2 inch dual exhaust with Flowmasters. No crossover pipe. HEI ignition.

That's probably more intake manifold than I'd have picked, but I own it and it looks great. The motor feels and sounds fairly low compression to me, and the cam sounds stock, but again that's just a guess. The car runs fairly well, but any motor can push a 2000 lb car pretty well. I want to hot rod the engine but I need to know what I'm starting with.

Should I look for serial numbers? Do a compression test? Where do I start?

Thanks in advance...

Glad to see you participating. Numbers from the block and heads will be a good start.

In addition to the casting numbers Mikey referred to there is also a pad on the passenger front edge of the block just at the block deck. If the block wasn't deck milled there should be some stamped numbers there. The basic casting may be appropriate for a variety of engine configurations so those stamped numbers, when decoded, will give further clarification. All that being said, these engines are so prone to modification that the original data can be rendered of minimal value. A partial tear down and inspection may end up the best solution depending on how committed to accuracy you are.

Punch the numbers you glean into Google/Bing and all sorts of info will pop up.

Thanks for the add'l. information.... "Bobby"!

Originally Posted by 34_40

Thanks for the add'l. information.... "Bobby"!

...........

Thanks for the replies. I guess I'm most curious about the compression ratio at this point. Can I just do a compression check to figure out where I'm at? I'm at 6000 ft so I guess any given compression ratio will yield a bit lower actual pressure? How much difference in cylinder pressure is there between say 8:1 and 9:1 ratios?

Originally Posted by ocezam

Thanks for the replies. I guess I'm most curious about the compression ratio at this point. Can I just do a compression check to figure out where I'm at? I'm at 6000 ft so I guess any given compression ratio will yield a bit lower actual pressure? Hoe much difference in cylinder pressure is there between say 8:1 and 9:1 ratios?

Depends on the camshaft intake closing point. If the 8.0:1 motor had a short cam and the 9.0:1 motor had a longer cam, the 8.0:1 motor could show more pressure on a compression gauge because the intake valve closed earlier, trapping more mixture in the cylinder. The only way I know to find the static compression ratio of a motor is by using all the data to figure it mathematically. You need 5 values, cylinder volume, combustion chamber volume, piston crown volume, piston deck height volume and head gasket volume.

To begin understanding cams and how they work, start with reading the thoughts of a brilliant cam designer, Dimitri Elgin.....
http://www.crankshaftcoalition.com/w..._Dimitri_Elgin

Here's another wiki article that I wrote that gets into matching up of cams with different static compression ratios....
http://www.crankshaftcoalition.com/w..._compatibility

Another article I wrote deals with properly adjusting the valves....
http://www.crankshaftcoalition.com/w...stment_SBC/BBC

The Victor Jr. intake is rated to operate between 3500 and 8000 rpm's, so it is not the street-friendly intake that you need. Building a motor is a matter of choosing a combination of parts that contribute to a certain end product, so seeing a Victor Jr on a street motor would tell me that the builder had no clue. The other thing that's not helping with horsepower on the street is the shorty headers. Sling that junk over the fence and install a set of equal-length, long-tube headers with an H or X pipe imediately after the collectors.

Now, I'm wonderin' what's inside the motor?
This is the main reason that I will never purchase a motor that is together. In every case, I'll buy parts and engineer the build myself. You may or may not have that expertise, but you can certainly learn.

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Yeah, I understand the difference between static and dynamic compression ratio via the cam. I just wasn't thinking the situation thru, thanks.

I'm also aware of the Victor Jr's less than ideal street specs. I'd have never chosen it. That said, the car really does well off idle. It's hard to keep the tires from breaking loose.

I guess I'll end up taking the heads off and figuring it out. Will be a while though, having too much fun with the car as is. Probably a good winter project.

Thanks for all the help.

Is there any way you can contact the builder or the previous owner?

Originally Posted by rumrumm

Is there any way you can contact the builder or the previous owner?

I've been working on that, no luck yet.

Thanks for all the replies!

Originally Posted by ocezam

I've been working on that, no luck yet.

Gone to Aruba, spending your money.

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