305 to 427

[80sman]

In a week or so I will be getting the engine out and open it up. I will keep you guys posted. Thanks for the help

 

[WFO]

427s and 454s have the same bore but different cranks. The 396s and 427s use the same crank which is externally balanced while the 454s are internally balanced.

You've got that backwards.
454s and small block 400s are the ones that are externally balanced.

 

[RanchWelder]

Compre-HENDING STANDARD AND REVERSE ROTATION MARINE​

https://enginepro.com/understanding-standard-and-reverse-rotation-marine/

 

[80sman]

I haven't forgotten I've just been to busy. Got the engine out about a month ago and tonight finally opened it up a little bit. Some photos I had taken including the cam specs I could make. All the measurements were made straight off the cam, first 2 sets for the lsa and lobe lift were with the degree wheel set close to TDC but figured that didnt matter since I wasn't degreeing the cam. I also swapped to a different dial indicator since it wasn't providing similar results. Second set I believe to be more accurate. First time I measured I set the dial indicator to 0 and when I measured the next lobe I didn't turn the dial just moved it around on the head to try to maintain a more accurate measurement. For the lift not sure why I put a degree symbol instead of a decimal.

One of the photos there's some rust and unsure what to do about it. Wipe it off and see how it looks? It is a flat-tappet so it's fussy on how smooth it is. It does have solid lifters. We figured the engine only has about 2-3 races on it but was put together with new and used parts.

I've yet to pull the oil pan, I need to put it on a engine stand first.

For a torque converter what stall should it have?
Intake lift .329
Exhaust lift .339
LSA 109 ish

 

[80sman]

Don't accuse me for my setup, that's all I had. Im more a machinist then a engine builder

 

[xm20k]

So that's
.559 intake
.576 exhaust
with the stock 1.7 BBC rocker ratio

It's bigger than stock but not by much as far as a BBC goes. But not sure what cast heads will support either. Probably wouldn't need much stall maybe 2500 to keep it from trying to lunge thru the brakes at a stop light.

My .550 lift 242 duration 107 lobe sep. stock bottom end 350 ran a 2500-2800 off the shelf converter with no issues.

 

[80sman]

How did you figure that based on the specs I gave you?

What would you do about the rust?

 

[xm20k]

How did you figure that based on the specs I gave you?

What would you do about the rust?

Lift is height of lobe above base circle (your numbers) X rocker ratio which by the picks appear to be stock with upgraded hardware.

Works the other way around as well to check for lobe wear, example mine are .600 lift with a 1.5 ratio rocker which makes the actual lobe .400 so like you did I could run my dial thru the lifter bores or use a micrometer if it's outside the engine and check for any with a bunch of excess wear. Or find the lift of a mystery cam.

As for the rust if it's just surface id lube it and run it but if it's starting to pit the surface, I'd source another with what I was planning to do with the engine in mind.

I'd also roll it over and look in the bottom end at main and rod bearings before I did anything else.

 

[Rustisbest]

What's the duration measure at .050?

 

[xm20k]

Ah yes roll it to .050 note the degree spin it up over the lobe till it drops back to .050 and note the degree there's your duration.

 

[Rustisbest]

And that gives you the whole story not just a couple chapters

 

[80sman]

Ah yes roll it to .050 note the degree spin it up over the lobe till it drops back to .050 and note the degree there's your duration.

Ill have to figure that out Monday. Will both intake and exhaust lobes be symmetrical?

 

[xm20k]

Ill have to figure that out Monday. Will both intake and exhaust lobes be symmetrical?

Sometimes they are sometimes not, both of my cams are but a lot are split lift and duration.

 

[80sman]

Update, I measured for duration but cant find the paper I wrote it on but 45* and 170* something is what I think of. Near positive on the 45 but not the 170.

I've pulled the pan off and found some more rust but it all wipes off with my finger. Im thinking just put it together and run it.

 

[Ricko1966]

In a week or so I will be getting the engine out and open it up. I will keep you guys posted. Thanks for the help

@txaggie Has your accessory brackets click @txaggie and start a conversation with him