Removed one of the heads to see what was underneath,and took some quick measurements.Did not have the best equipment and it is cold here now so the measures are approx.
I have low comp.pistons.
The syl.bore I measured to 3,86".Did not measure for any ovality.No scratches that I could feel.
Intake valve 2"
Exhaust valve 1,62
Camshaft I do not know how to identify this.
If I decide, to build this engine to hi-comp spec.,are there any other parts that has to be replaced.
The intake and carb.of course.
image.jpg

 

Is this a 307? If your measurements are accurate, it is already .060" over and I wouldn't try to bore it any further. The only pistons you will find are cast pistons and they are all low compression. You can go custom to get a high compression forged piston.

Those valve sizes sound like big valve small block heads. I would be surprised if they fit in the 307 bore but with a .060" over block they might squeeze in there. You probably have combustion chamber overlap on the bore if these are 350 heads.

Stock 307 valves are 1.75 and1.50. What number is on the heads? Is there an "A" with the number? Is it smaller than the number or the same size?

I have never heard of a L65.

 

What letter is cast on the top of the block behind the timing cover? And what letter are the heads?

Did you mean L69; that is the 66 "track pack". Otherwise your bore sounds like a 68-69 400ci G block. However the G would have C heads with 2.07" intake, 1.625" exhaust valves. I think you have a 400 G block with small valve C heads.

 

Looking at the picture again, I believe those ARE high compression pistons. Low compression have way deeper dish.
High comp 455 factory piston:

 

Yeah, I didn't think of the small bore 400.

 

It may be wrong to call it an L65 engine.It is a 68 442 with the L65 (Turnpike cruiser) option.400 cid engine,low comp. pistons,2"intake valves and a 2 port carb.Might be other differences too? I am considering rebuilding it to high comp.specs,and asking for advice on this project?

 

I don't think there are any high compression pistons available for that engine. Most likely you will have to go with custom pistons.

Only other thing you can do is find factory pistons or mill the heads for compression.

 

Well,do not know what you consider high compression,but a regular 442 has
10,5:1 while mine has 9,0:1.What I meant was changing to the standard 442 pistons.

 

My mistake, sir. I forgot about the turnpike. I've been working on a couple 455's lately and its been a while since I've been into the 400G. I forgot the the high comp 400's had flat tops.


I'm not sure if there is a replacement flat top piston available for the 400G. However the .040" Speed Pro with .040" gasket on my engine came out to be 9.75:1. Your results could be different based on deck height, head gasket, and head volume.

 

Supercars unlimited has them:

http://www.supercarsunlimited.com/Pistons-i105.aspx

 

Havent been much work on the car lately,too cold and going to stay cold for a while according too the forecasts.
Dont have the service manual infront of me,but remember reading something
that struck me as odd.
It says not to deglaze the cylinderwalls if you change pistons.
This is written somewere in the engine section.
Thought honing to a crosspattern was the way to go.

 

Another thing I would like to know.
C heads with 2" vs. 2,072" intake valves,the larger seems to be standard 442.
Can the heads with the smaller valves be converted to the fit the larger ones?

 

No problem. Machinist will cut seats to new valve size.

 

Do you have high octane fuel available to run higher compression? Don't build for over 9:1 unless you ave 95-100 octane fuel.

The TC pkg is actually cleverly engineered, and you would do well to leave it alone.

These jokers think a '68 442 has a 350 engine?
http://www.ebay.com/itm/Sealed-Power...bbce5f&vxp=mtr


These hosers think it should have a 455:
http://www.ebay.com/itm/TRW-Oldsmobi...5904c9&vxp=mtr

it gets better
these guys sell 8 pistons, for your V6
http://www.ebay.com/itm/Set-of-8-NOS...ed90ef&vxp=mtr

The '68 442 with the rare straight-6 Chevy engine
http://www.ebay.com/itm/Set-of-6-NOS...e67c2f&vxp=mtr

The bullshed and misinformation just gets worse and worse over time.
In a few years, we'll have folks advertising Ford parts as correct for the 442.

Here's a REAL RARITY- accurately described Oldsmobile G400 pistons
forged
std bore size- if your bores are not scratched, good for you
dirt cheap at $350 the set
did I mention *FORGED* stronger than stock?
will require much larger wall clearance, a good excuse to hone your cylinders afresh.
http://www.ebay.com/itm/FORGED-Pisto...71e3b2&vxp=mtr

Another set, and they ship to Europe
http://www.ebay.com/itm/Oldsmobile-p...15d80e&vxp=mtr

Your cam will be Id'd by the notches and chamfers on the front surface. See the chart in the Chassis Service Manual. Buy one and/or join the FREE organization WildAboutCars.com where you can view what you need for free. If you are not already a member, WHY ARE YOU WAITING??? This goes for ALL READERS OF THIS....

 

They already do.

Rocker arms.

Kinda, sorta, Ford 460 rear main seal.

 

We still have 98 unleaded here.What do you US guys use?
Cant you get additives to prevent self ignition?

The cam seems to be the same as in the regular 442 engines.
Already member of WAC.

 

Well, yah, but those FIT and WORK right.

I defy you to use a 455 or 350 piston on a factory '68 442 engine.

Or, 8 pistons in your I6.

 

Your 98 octane isn't the same as our 98 octane.

 

Who cares what they originally fit? As long as a part can be modified to work right.......who cares what it was originally made for?

 

Which one is the best,yours or ours?

There is no octane in the fuel here anymore,but what the call 98 octane nowadays,is supposed to resist self ignition like fuel made of 98% octane.

 

The octane ratings in Europe are different the US

98 octane Europe = 93 octane US Still a high octane by today's standards

 

My point exactly.
I have run 10.25:1 engines, and they really do NOT like 93 USA octane.

They do however love 100 octane airplane fuel and 110 octane race fuel, even at 25% with 75% 93 pump gas.

So, again, if you have a 9:1 Turnpike cruiser pkg, a well designed and engineered combination... fix it up and enjoy it as is. Easy to operate on pump gas, and not really that much less performance than the 2.07" valve 10:1 engine... all else being equal.

 

image.jpg

And the reason for this is?

 

Image is too dark, can't see any detail
Use better lighting
automatic camera settings maybe?

What is it, a carboned up head? The one whitish valve?

Looks fairly normal to me for an old used engine.

 

Bad picture.Sorry about that.
I was wondering why that one exhaust valve is white?j