RoadKill Garage 351c Build

 Common Chevrolet engine building takes an engine block and punches it out 0.030” but on our Cleveland cast iron blocks core shift makes this an unwise automatic approach. 

 My recent build was fine with just 10 over and that gave me 404ci.

20 over = 406ci

30 over = 408ci

 The less removed the more stout the block remains and should any mechanical issue damage a cylinder bore I will know there is still sufficient material to clean up a damaged bore rather than look for a new block  

Larry

Ah - that makes sense.  I wasn't thinking about bore size.

My numbered block was taken 30 over at some point, so I plan to retire it for later posterity instead of using it as the basis for a stroker.

I'm using the trick flow heads but no stroker kit.  The engine pulls hard but unfortunately I don't know HP numbers since its never been on a dyno.

Which volume intake runner version are you using?  There are three 225, 195, and 190.

Do you know what your static compression ratio is?

From memory which isn't always 100% these day.  I used the 195 and the static ratio is approximately 10:1.  I have all this info in a file including the cam specs etc. If you really need it.

I had a 393cuin with Comp Cams custom grind mechanical roller, grind 2314F/ 2318F, 250 - 258 @ 0.050, gross lift 0.640", lobe separation 110, cam in at 105.5. Used Scott Cook heads and dual plane intake, 640 hp @ 6,600 rpm, 537 lb-ft @ 5,800 rpm. This was also with Pantera Pat Mical headers. 11.2:1 compression ratio and ran on 93 octane. I idled it at ~ 850 rpm with 10 - 12 of vacuum, I was happy with the brakes. Up to you but I would not use a mechanical roller on the street, I broke a PAC conical valve spring with its no longer attached valve and later wiped a Manley Enduramax roller follower. It was good while it lasted, 21mpg on a run with FI and was fun.

Seems my engine output was slightly down in comparison with a smaller engine, smaller cam and lower rpm. Dyno headers gained ~34 hp over stock GTS headers on one run but I am not sure there was a good comparison run between Pat Micals, dyno and the GTS headers. My heads also had the incorrect exhaust valves which Scott said was bad. 

Waiting for a Tim Meyer aluminium block and using Scott's recommended roller hydraulic cam and use the correct valves. That one day will be dyno'd.

Good luck with your engine choice, there are many possibilities..

Trick flow 195
20 over
10.4 static...normal European petrol (94 Euro),
Ross custom pistons (20 over)
10 deg advance
dual air gap Edelbrock MODIFIED as Trick flow intake is higher so need to modify
Crane cam think 5900 max (nerver really get there), ok idle, need to check serial number)

tremendous power

I'm curious about the intake port location change on the Trickflow heads.  How did you have to modify the  Edelbrock air gap?

Do you have to machine stock type intakes or is it more of a port mismatch issue?

Trick flow intake ports per spec are a bit higher..(need to figure out how much).
I DID NOT do anything on the heads..as more precious..(smile). I modified the Edelbrock intake, is a bit tricky but via a tube cam could be done.

Modification just by fileing the upper portion of intake ports.  It is mainly on the top side as Heads are a bit up and intake hence too low/missmatch..The rest I did by playing with the gasket thickness. I did the gasked from scratch by special gasket paper..they come in different thicknesses.

 (I have digi cam pictures but hard to understand without lots of explain.)

(also you need to "Flatten" the carb side of intake by milling to make it "Flat" as original has an angle..then it fits the deck lit etc..). You Still need to modify the engine cover/the mesch metal thing..

FWIW, I agree with Larry. We both know a POCA member that had a stock Cleveland bored 0.040"-over, and a year later, the rings were still not seated. Due to 10:1 compression and thin walls, there was always blow-by from flexing cylinder walls. Please do not scrap more increasingly rare 351-C blocks by boring without first sonic checking cylinder walls! The 351-C is NOT a 350 Chevy!

Note also that in N. Nevada in the past year, we have had two separate examples of semi-pro built 427 stroker 351-Cs  that incessantly burned oil. With a 4" crank and stock height block, the wrist pin is forced to go thru the oil ring grooves, and both builders did NOT use a ring support rail (or the alternative- piston pin plugs). Without support, three piece oil rings will bend down at the big pin-hole from compression pressure on both sides, and open direct paths for cylinder wall oil leakage.

The result was a decent running engine that burned a quart of oil per 100 miles. After I found the ring support rails missing on one engine, the second owner pulled his engine and found the same thing (different shops did the work). Rebuilds with proper parts resulted in far more power, better gas mileage and oil use of a qt/2500 miles for both. Both owners are very pleased with their big engines correctly fixed by shops familiar with 351-C engines. I can't stress this enough- even if 351-Cs are from the '70s, they are NOT simple engines!

If your stroker burns lots of oil, look for that necessary oil ring support rail at the bottom of the piston ring oil grooves- they're really necessary for a 351-C with any crank over about 3.75" stroke!