build vs crate

SS Shaun · #1 08-28-2012, 09:52 AM

well something i am going around talking with a friend of mine. i have a target goal of trying to get 400hp and anything over 400tq. I have a 454 right now that i know is a dog! after doing the calculations we figured its going to be in the mid 7.x:1 compression. which is going to be about 200-250-hp to maybe 300tq. So i told my friend we can make my 454 a very nice 496. so we went and did the math and matched everything to get me some real power out of it but the cost was more then getting a crate 496. On the flip side we calculated it will have over 500hp and over 500tq. but is it worth it for a street car? So i ask what would you guys do? build it the way you want it or just get a crate motor from jegs or summit?

carpoor · #2 08-28-2012, 10:11 AM

A few questions about your 454:

Is it healthy? As in... Checked the bearings? Leakdown and compression test?

If so, I would do a budget build. SFT cam, a set of closed chamber heads, and all the supporting mods. Don't get hung up on SCR, the DCR is important too. My 468 is only 9.65:1 SCR, but 8.57 DCR. It is going to have a wicked TQ curve for such a "stock" engine. You'll have the benefit of headers, roller rockers, and much better intake manifold.

Just food for thought...

Berg · #3 08-28-2012, 12:26 PM

I feel it all comes down to how much machine work you'd have to do- that's where a lot of the cost will be. You could also do a poor man's head swap and run the 100CC Gen 6 Vortec heads on you Mark IV 454 with dished or flat-top pistons. If you are in the neighborhood of 7.0:1 or 7.5:1 I'm going to venture to guess you have dished pistons. In this case, doing the head swap should put you around 9:1 and combined with a healthy camshaft and a nice intake and carb with HEI ignition I think you'd have a pretty powerful combo that would be totally streetable.
There is also the benefit of having a nice warranty that comes with a crate engine. Personally, I like the 454 HO crate engine from GMPP. Kind of hard to beat that deal!

Garyb · #4 08-30-2012, 01:01 PM

For me it would be a no brainer, i'd have it built locally. Mostly because the builder here does outstanding work. I had a pair of 781 heads done by them and was amazed at the quality.

carpoor · #5 08-30-2012, 01:51 PM

Just going to add my "crate engine" experience. I payed for what was supposed to be a quality engine from a well-known builder. What I ended up with was a steaming pile of crap. It lasted exactly 202 easy street miles, and 7 dyno pulls to get the tune right. When I called them for help, they wanted me to ship it back at my cost. And hold my engine for ransom if they deemed it was my fault. (mind you they machined & assembled it) I refused, and wanted to have it inspected locally by an impartial 3rd party - at my expense. They basically told me to shove it and called me a liar.

Since then, I have searched for a local guy that I could trust to farm out what I can't handle. Now, I have someone less than 20 miles away that will help me if needed. It's nice not having to travel 12+ hours to speak face to face with someone.

Just my $0.10...

P.S. - if you want to know who that "reputable engine builder" was, the initials S.S. should clue in at least 90% of you reading this.