Thread: 1969 350 5.7 small block but which one is it??

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i got a 69 small block chevy out of the camaro but dont know which it is? the 250bhp.......255bhp......300bhp ?

its defo not the 300 lol....its pi$$ slow....so slow im questioning if its a 350 at all......does anyone know what a 350 5.7 should do 1/4 mile /0-60 in a 77 camaro car?

because the engine sounds smooth and powerful on when car in nuetral lol but soon as you gear it up its like its pulling two trucks? whats with that...

At the time of manufacture, Chevrolet stamped a number on the block deck. You can find it just in front of the passenger side cylinder head, probably under the alternator. That number will give you the skinny on the origin of the motor. If you don't know how to run it down, post it up here and one of us will help you.

If the block has ever been decked at a machine shop, the number will have been cut off and you're outa luck.

I think I'd start with the basics and do a compression test on the motor. Warm the motor up, remove all spark plugs, wire the throttle blades wide open, disable the coil and do a compression test on all cylinders.
http://www.search-autoparts.com/sear...l.jsp?id=16170

Edit: I see you have already posted CHN on another thread and it doesn't come up in the lists I looked at. I'll keep looking for you. Are you sure it's CHN? Here's a page showing where to find ALL the numbers on a small block Chevy....
http://www.73-87.com/chevy_ids/sbcid2.htm

It could be a 262, 267, 283, 305, 307, 327, 350 or 400.

Use this list of number locations to try to chase it down further, particularly cylinder head casting numbers under the valve covers and the casting number on the back of the block at the driver's side (well, driver's side in the U.S.)....
http://www.73-87.com/chevy_ids/sbcid2.htm

You said you feel robbed......

Well, here's the NADA value on the car in US$. The current conversion factor dollars to pounds is 0.607, so the low retail figure of US$ 4,150 would equate to L2519. Looks like you paid L2160 for it, so I wouldn't necessarily feel robbed if I were you.
http://www.nadaguides.com/default.as...9&z=85283&da=1

ohh no...ive just realised that it also could be the CHH 307 with just 115BHP


engine number is CHH which covers BOTH 1978 350 170bhp and 1973 307 115BHP

its certainly not good!!!

ok...what im now assuming is it IS in fact a 1973 307 with 115 bhp....

they only ever made 2 CHH letters.

1st is the above mentioned coming with a TH trans

2nd is a 1978 350 170 bhp with an auto trans

ok....

so.... this engine in the car reads CHH on the engine and it has a TH350 trans.

therfore it HAS to be the 307 right?

However....ive just got onto the bloke who sold me the car and he told me that because the camaro was originally a 4.1 straight 6 with a th350 trans

so he said this bolted straight on to the V8...now i am confused!!!

The only way to really tell - is the casting number. This example is a BB, but your number should be in the same general vicinity. The diagram shows all possible locations as "2", "2A", and "3" (picture shows location "2").

You've already identified the engine suffix code, i.e., CCH as a 307 or 350.

Give a look - maybe with a mirror - and let us know what you find. If it's a 307, don't completely despair. There's hope to get you a bit more snap - but not as much as we can find inside a 350.

Here's hoping it's a 350!
Glenn

thanks for that.....if i fail to be able to find thats number....

would it be a lil easier to remove valve cover for head casting?

research tells me....if its a 307 the numbers will be either.....

1968-73 3932373
1968-73 3931633

or if its a 359 it should read one of these......

1973-80 340292
1969-79 3986330
1978-80 460703
1969-79 376495

but where? and how do i remove valve cover please?

The valve covers are the rocker covers. There are 4 bolts, 7/16" socket typically takes them off nicely. Be prepared to replace the gasket - if they're cork - they'll be buggered and not seal again. If they're rubber, you may get away with re-use, but I'd replace them.

The pictures below show several small block head types. Your's will probably look similar to the top photo (with all the valves and rockers in place of course). The number will be a six, seven, (or possibly eight like the 14014416 in the picture) digit number. Write them down and give us a shout..

Glenn

spot on......il be having a look at that....the rocker cover gasket is weeping a little oil anyway,so shouldnt make that much difference if i take it off to have a look.

looking at the engine from the front, is it the cover on the left hand side or the right of the carb?

or doesnt it matter? i appreciate all your help.

Both cylinder heads will have casting numbers. Pull both covers and check both numbers to insure they are the same.

Ok, got some news to go on,

I havent took the covers off yet as my gaskets wont b here until 2moro,however.

The numbers on the block read as....

3970010 and jst b4 that it says GM 46.

3970010....302.....69....4-bolt mains...Z-28 Camaro
3970010....327.....69....2-bolt mains...Trucks and industrial
3970010....350...69-80...2 or 4-bolt mains
http://www.mortec.com/castnum.htm

That’s good news. As mentioned above, this number is associated with 302, 327 and 350 motors – all of which can be screamin’ fast. Now we need to find out why this Camaro of yours is a slug.

While I appreciate your zeal to jump in and figure this one out – it may be in your best interest to find a real Chevy mechanic shop in London and have them at least perform a high level diagnostic on what’s up with your engine.

It may be a simple issue, like timing being off or a vacuum leak at the base of the carburetor. It could be compression related, i.e., bad rings or valves.

If you’re set on doing this yourself, here are the steps I would follow:

1. Purchase a manual covering the above mentioned engines – if you can’t find one locally, go to amazon.com and order this one: http://www.themotorbookstore.com/camarors.html
This will become your constant companion and source of lots of vital information.

2. Perform a basic tune up with new spark plugs, air filter, distributer rotor and distributer cap. Set your timing at 8 degrees with the vacuum disconnected (and plugged) from the distributer. When you have the cap off the distributer, make sure the mechanical components of the vacuum advance are free and rotate easily.

3. With the engine off, make sure all of the carburetor linkages work smoothly and that the secondaries open up.

4. With the engine running, check for vacuum leaks. This may be accomplished by spraying carburetor cleaner at the base of the carburetor and along the intake manifold where it bolts to the heads. Any change in RPM indicates a leak and that will definitely hurt your performance.

If the above steps don’t restore some real zip to your engine – it may be time to go a bit deeper and perform a compression check as per the advice of Techinspector above.

Have fun and let us know what you’re doing.
Glenn

good stuff, thanks...........

so il take off the rockers tommorro and see what they reveal.

i would like to narrow it down to which engine i got.

the suffix number only covers 307 and 350. does this mean its a 350?

tell you what i was thinking with this puzzle.

originally the car had a 4.1 straight 6 in it because this boddy is a 77 camaro LT.

the guy tells me he took the straight 6 out and droped in a 350.

now with the LTs diff ratio being suited for the straight 6

surley this could be the problem with it now having a v8 with more power? ?

ratio is wrong?

he also told me hes using the original trans TH350 from the straight 6

so basically all in all, its a v8 running thru a straight 6 trans and rear axle ratio.

maybe the problem?