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Cracked Big Block


Well-known member
Jul 3, 2001
Auburndale, Florida
1969 Killer Shark
I did some horse trading and sweat equity to obtain the 454 short block for my 69 project. It is nothing really special other than having a steel crank.

I noticed when trying to mount it on my engine stand that the far low driver side trans mount bolt hole (right next to the oil filter casting) is cracked off. You can see the inside edge of the thread and the outside is missing. There is not enough meat there to run a bolt through.

Is this common? Can it be welded?

Any suggestions?
Hey Chris, your machine shop can do this NP. I've tried to weld cast iron before without much success.
Good News!

Dropped the block off last night and it went to the "expert" welder today.

They decided to weld in a stud to the block in place of the original threaded hole.

This should work fine and not cause any other problems.

Next stop-the machine shop.

Hope to have the short block together soon.

550 hsp, here I come.


Youre in for some 'oh babies' when you get that 550 h.p. to the road ! I did a major engine buildup last winter on mine - went from 390 stock h.p. to 540 + h.p. (torque at 540 +). Its great having L 88 performance - actually a tad scary at times.

Bon appetite !


If you saw my latest post, I am all of a sudden stuck on the fence. I plan on putting the BB in the car. However, I have a ready to go super nice high output, high tech roller small block just collecting dust in the garage. If I throw that in, I might be driving this thing in 4-6 months. I could work out the bugs, then throw the bb in later.

On the flip side, spend the bucks, finish the BB and delay my project 4 to 6 more months.

I am trying to stay patient and take my time. There is a plus and minus either way. However, the more I think about it, I just won't be happy unless the BB is in the car.

You give me more inspiration to go with the BB.

There wont be any comparison between your SB roller motor to a BB motor with 550 ponies. Theres other benefits too besides the ground pounding torque : the sound, the asthetics, the nostalgia, the resale value, and the 'name' !

Rumpity Rump,


I am actually calling Edelbrock today to go over the parts one more time before making my order.

They ran 547 hsp with their heads and cam using the Pro-Flow EFI on a 502 Chevy Crate Motor.

They built a .060 over 454 with the same cam and heads running a carb at 539 hsp.

Since I have the 454 which is already .030 over, and plan on running the EFI, I need to speak direct with them to get the best matching components.

They have a new head out for the 454 oval port with only 100 cc chamber vs. the 110 on the other head. This would help me bump up a little more than the 9.6:1 as adverstised. However, they are not in stock right now. That may be fine as it will still be sometime until the car is 100% ready to drop in the motor.

After I get the rest of the details, I will have to run the budget one more time.

I have the entire Edelbrock Package consisting of : Thier cam (.553 lift), RPM Oval Port Alum. Heads, RPM AIr Gap Intake, Timing Chain . What i noticed immediately versus the old iron original heads. is how much more air the engine flows - id say at least another 35% ! Feeling the exhaust at the Tips , it is pushing much harder now. Thier chart says im at 540 h.p/539 Torque BUT that is using thier 750 cfm carb - im using a Speed Demon 850 dp with mech sec. Carb with insulator and cold air from the L 88 hood . I expect my actual h.p. to be closer to 575 . (I think i could have even used a 950 cfm carb , as i had to bump up the jets in the 850 Carb to #85 for pri. and sec. and bump up the discharge nozzles 3 sizes, in addition). Thats how much more airflow the Alum. Heads and Intake contribute . The car is the fastest car i have ever been in and that includes a 2000 C5 4 speed, a 1965 429 Ford Galaxy with 411 gears, 1971 440/6 Pak Plymouth GTX, and 1969 BB Camaro 4 speed built by a Prof. Racer. Surprisingly, i still get 11-12 mph around town if i stay on the Carb primaries . The Block is the original and houses 11-1 CR SpeedPro Forged Pistons with new rings, hi perf. oil pump, and all new lifters.

I cant think of anything else i want to do to the motor - i love it exactly the way it is now. Eventually , when i need a new cam, ill go for a hydraulic roller with roller lifters.

Email me when you take the 502 out for your first spin ! I think that EFI is going to be a real plus .


Excellent. Knowning that you have been there and done it is a great confidence booster.

You should be making more power based on the fact you have 2 points higher compression and more fuel than the test engine.

Do you know the part number on those speed pro pistons? I am looking at the TRW L2399F that would push 10.2:1 with the new 100 cc head and Felpro head gasket. However, the TRW is heavy at 679 grams. Did you deck the block at all?

My Edelbrock Catalog says something about there being a clearance problem with the spark plugs when running high compression pistons. Did you run into anything there?

The Electronic Fuel Injection Pro Flo system includes a 1,000 CFM throttle body. However, that is dry vs. wet as in the measurement on a carb. They say it is good for 600 hsp and they have been testing it up to 700. Very expensive, but I am better with electronics than carbs.

I already ran the extra hard fuel line before dropping the body on. This allows me to have a feed, return, and vacuum vent. I plan on trying to mount a charcol canister in the rear of the car as with sidepipes, I don't have any hot mufflers to worry about back there. Plus, it should cut down on fuel smell when it is in the garage.

I would like to know more about your car. Are you running roller rockers? Power brakes? I was told the tall valve covers are a big problem. Any insight there?

I appreciate anything you can share with me.


I had no clearance problem on my plugs. Use Champions RC plugs - theyre .230 inches shorter. Edelbrock recommends them too. I didnt deck the block and i dont know if it was done prior to me buying the car. I didnt do the bottom end..only the top end. Yes, i have Comp. Cams roller rockers 1.7 ratio . My standard valve covers fit ok, and thats with using positive locking rocker arm nuts (which are bigger- it must be very close though)

Ill email you a few pics i just got on my vette.


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