What engine should I build?
Thread Starter
Burning Brakes
Joined: Jul 2002
Posts: 1,126
Likes: 99
From: Nova Scotia
What engine should I build?
I can't decide what to start with for my engine. Im thinkig either starting with a gm 502 short block, or a 454 block bored 30 over with a 4.25 stroker crank to make a 489. I dont know how strong the bottom end is on the 502, and also the pistons would give me a pretty low CR. but the bigger bore would help it breathe better and the shorter stroke would help it rev easier. Either way Im thinking of building to rev to 6500 rpm, so peak hp around 6k, and Im hoping for around 600-650 hp its going to be mostly for the street with the occasional trip to the drag strip. Any suggestions or advice appreciated. thanks
One gear at a time
Joined: Aug 2003
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CI 8-9-10 Veteran
St. Jude Donor '07-'08-'09
I built a 496 for my girlfriend's Malibu. I viewed the project this way: Since I had a 454 core, I decided to build it. If I was planning to buy a new block, I would definitely go with the 502 block. I got my rotating assembly from Speed-O-Motive. The stroker kit, with longer rods and forged 10.2 : 1 pistons only cost a couple hundred more than re-using my crank rods and ordering new pistons. Good luck.
Race Director
Joined: Jan 2000
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From: Corsicana, Tx
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Just go ahead and build a 540. Doesn't cost anymore. If you are having to buy a block it changes everything. If you already have one...might as well use it. From the dyno tests I've seen (real ones..not magazine ones or DD2000 ones) the increased breathing of the 502/540 large bore really helps. On identical 496/502's..the 502 will be up approx-25-30hp over the 496.
ML67 here on the Forum has a set of forged flat top SRP pistons for a 540 that would be a cheap way to get started.
Just make sure you select heads that can feed them. Don't go too weenie....it will make a big 'ole truck motor! Heads that were designed for a 396/427 will runout of air fast if you add another 100-150 or so cubes to the mix!
JIM
ML67 here on the Forum has a set of forged flat top SRP pistons for a 540 that would be a cheap way to get started.
Just make sure you select heads that can feed them. Don't go too weenie....it will make a big 'ole truck motor! Heads that were designed for a 396/427 will runout of air fast if you add another 100-150 or so cubes to the mix!
JIM
