Thanks Ted, that’s some good info!

I’ll keep in mind valve float up around 5500.

The edlebrock carb is a new performer 14063. It seem pretty good but I wouldn’t mind some o2 sensors to get it right. I’ll make sure I’ve got a handful of bits and pieces for tuning. I’ll have a look at the secondary’s weights, thanks for that tip.

It might be a while until dyno day but I’ll post up the results.


Thanks, Dennis.

56 F100 - 272 Y Block
NSW, Australia.

My two cents worth here.
 
The bottom end is more than capable of running up to 6500 rpm when all is correct in that area but head/intake flow and valve train will be your limiting factors.  Dead stock 2V engines were typically peaked out at 4500 rpm and would eventually go to 5000 rpm if just staying in the throttle before valve float set in.  In your case, I suspect that your engine will be peaking at 5400-5500 rpm with the camshaft you have selected along with the other parts.  As a general rule, the 2.02 inch intake valves are not as good at producing low end power in those small bores as the 1.92-1.95” valves but can understand using the larger valves when trying to salvage the existing valve seats.  Intake valve shrouding tends to be more of a power deterrent than whatever is gained by increasing the actual valve size and especially when dealing with the smaller 272 bore sizes.
 
While the Carter and Edelbrock carbs can be counted on in cranking up and idling just fine, they can be finicky in getting the tune just right for making those peak power numbers.  You will need a collection of jets and metering rods on hand to make adjustments during the dyno session.  Keep in mind that those carburetors are fuel pressure sensitive and may require some float adjustments to compensate for your particular fuel pressure.  Having a wide band oxygen sensor hooked up will speed up the tune up process versus just reading the spark plugs.
 
Consider removing some weight from the secondary counter balance weights to allow the secondaries to open a little earlier.  I do that using a scale to measure first the overall weight of the counter balance weights and then take the same amount off of each weight.  If you have one of the newer Edelbrock AVS carburetors, those do have externally adjustable secondaries and eliminates the need to pull the cover off of the carb to manually modify the secondary opening rate.
 
My estimate for rear wheel horsepower will be 200-210.

Lorena, Texas (South of Waco)

With the engine as is, what would you estimate the safe max rpm? After a bit of reading it seems like 5000-5500rpm max is the limit for safety. What are the limiting factors? Is it the just weight of the rotational mass and the lack of roller rockers, roller cam for the Y block?

What is likely to happen if revved up to 6000rpm frequently? (Don’t worry, I keep it below 5000rpm)


Thanks, Dennis.

56 F100 - 272 Y Block
NSW, Australia.

Drylakes, blacktie- thanks for that estimation. I’ll be sure to post the results. I just have to find a tuner with experience tuning carburetors on the dyno, not too many here in Australia unless you’re in the know.

Cliff- thanks mate, so happy with the heads now!


Thanks, Dennis.

56 F100 - 272 Y Block
NSW, Australia.

I was thinking 250, so we're probably in the ballpark.

Good job

I’ll venture a guess of 245 HP at the crank. A stock 272 was 182 so a 90 hp gain would be quite an achievement so I’ll say a + 63..not on a chassis dyno. That will be lower.
Don’t let the rear wheel dyno numbers be the know all to end all. Many are disappointed when they see the number. Unless you are building a racing engine, drivability it what its all about and y-blocks have always been very good driving and cruising engines. I can kick mine in the butt and see a true 100 mph but 2200-2500 and the freeway keeps up with any crowd I’m running.

56 Vic, B'Ville 200 MPH Club Member, So Cal.

Thanks Phill, that’s good to hear as the whole build I’ve been a bit disappointed that I couldn’t get my hands on a 292. I felt like I’ve been missing out on extra displacement.


RB, thanks. I tried to use the best stuff I could afford. I have other goodies like melling oil pump with heavy duty shaft, tubular push rods, new valve train, ARP rod bolts, ARP main studs, ARP head studs, the pistons are forged (only because they were the only ones they had left).

Joe- thanks, that sounds promising. I think I would like a bit more compression like 9.5:1 but I think I’ll just leave it as it is for now. This is the first engine I have rebuilt and had no idea about compression ratio until I had a lot of the parts already. It will be chassis dyno.
I’m already planning my next Y build. I’m thinking a blown (low boost 5-7 psi) 272 as I already have an old 272 with ecz-a or ecz-c heads. I’m thinking I’ll keep it simple and use the original heads and use oversized exhaust valves, factory cam and just give it a good going through. I just re- read the thread about the twin turbo Y and it got me all excited about boost.


55blacktie- it’s all real. The engine is in my 59 F100 running and driving. The 2.02sbc valves fit good, just had to take .060 off the top of the stem to get them the same length as the factory y valves. Cliff, one of the fellas on here put me onto the 2.02 SBC valves (thanks Cliff). The first machinist did such a bad job that I had no other choice to run over sized intake valves by the time I went to the 2nd shop.


Thanks, Dennis.

56 F100 - 272 Y Block
NSW, Australia.

Agree , a 1.92 or 1.94 valve will more than supply enough air for a 272

Is your build hypothetical, or have you actually acquired all of the listed parts for your build? If you are going to use 2.02 intake valves, you may have to notch your cylinders to prevent shrouding/clearance issues. I think the 2.02s would be more suitable for a larger-displacement engine.