Thread: Stock bottom end breaking point

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What is the most power you can safely put to a rebuilt 77 350. The crank and rods are stock and the pistons are a cast dish type.

What do you have in mind, Josh? It sounds like you have stock crank, rods and - even with a .060 over pistons it would be hard to imagine an issue with "too much" power.

What are your plans for the heads, cam, intake and induction?

Nitrous?

Give us a bit more to work with..

Regards,
Glenn

Well for now I have engine quest vortec heads with 1.94and 1.5s unported, 1.6/1 roller rockers, elgin 327/350 horse cam, performer rpm, holley 700 double pumper, Jegs street spark hei. The shop who built it told me that the engine made around 10 to 1 compression. The engine has like 30 miles on it. The reason I ask how much power the bottom end can take is because later on, after I upgrade the t5, I will probably want to have some head work done and possibly a bigger cam. I just don't want my engine to fail prematurely.

with a dish piston heads would have to be less then 64 CCs . just did them same build as what you have used about the same cam was a erson and used the speed pros hyper flat tops with the pbm thunder heads up grade to arp rod bolts .nice mild build .i would say were your weak link is the cast pistons they will not like to much of a beating if you put any power adders the hypers will take abit more .used a set on a 350 with a B&M mega blower with 10 of boost many years ago they held up for the beating and was a stock rod 350

What do you think would be the most horsepower my bottom end could handle?

the cast piston i would not push past 350hp or abit more BUT you should ask for how long ? with no power adders. and one bad tune up and they are gone .but i only use cast piston s for very mild builds.claimers hypers are not that much money . not ez to say you get past the pistons the big ends of the rods could move up grade past that your crank could be the weak link then the block your trying to put power thru a stock block but how well it was machined and put together as all plays in to it .would i build a cast pistons engine and put power adders on it NO .you never said that your trying to make for HP?

Well, it started out as a motor for a daily driver for a truck I had. I sold the truck and put the motor in a camaro I got for 400 bucks and a t5 I got real cheap. I bet my motor makes around 350 as it sits. I was just wondering for future reference what my options were. I am new to engines and did not want to go all out the first time around.

Concur w/Pat. Cast pistons good for about +/-350. Keith Black Hypereutectic Pistons start at about $200 a set and are a better choice with forged pistons being the best, but at over double the cost.

That said, your driving style/habits wll be the largest factor here. Good driving - longer life. High RPM launches and power shifts - shorter life and more likely to see the cast pistons fail.

well the one i just built was thinking should make 375 hp and that has hypers look around the mahle hyper piston .mahle make a great piston and price good. speed pros there others i used alot of speed pros i like the piston better then some others but now there made in inda you have to look them over good .but like any thing it all should be check out

Thanks for the comments guys. But ya know, if I was going to change pistons, I would probably do more mods. since this motor is in my car and running. I would want to take advantage of having the motor out.

well do what you like .if the caster come apart you can throw the hole thing out and start over what other mods ??

The best thing you can do for your current engine is keep the rpms down.......no 6 thousand rpm runs.......more than likely your not making anymore power at that rpm than at 5500 max.
The rpms will do the most wear on the engine,with high rpms your more likely to blow than lower rpms.
I have a 5.0 mustang and keep the revs at about 5000,it might make a few more horses at 5500 or 6000 ,but it`s a 1986 with over 200,000 miles on it and it still passes emissions.Been runnin the snot out of it for years and its still runs great.........if it blows it will not run at all.

Save the all out runs for a forged piston and crank motor with good rods in it and high flowing heads,I would run that motor as is and get another engine for a performance build,considering you will only basically be using the block from that motor,those heads are going to max at about 400 hp anyway,no use spending any more money on them and no use putting a forged bottom end under them.
That would be my plan of attack.

Thanks Shawn, thats what I was needing to hear. I needed to know if I would plan on enhancing this motor or build another one.