Big Block options? DOHC?
09-28-2003, 09:51 PM
#1
Burning Brakes
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Big Block options? DOHC?
Hey gang--
I have been looking at big blocks as an alternative to my twin turbo LT1 idea, and have found some pretty interesting buildups. Of particular interest was an article in the August 2003 issue of Hot Rod magazine. On page 18, it talked about a guy named Pete Aardema that took an aluminum BBC and bolted on a set of Porsche V8 DOHC heads. It's fuel injected and 440 CID. It makes 550 ft-lbs. at only 2500 RPM! Anyone else ever heard of this being done? I am interested in building a big block (probably from a Merlin aluminum block), but I must admit that I am ignorant in the big block arena. Can anyone offer suggestions as to the approach to building a BBC, parts that are of good quality, etc? I am just wondering if it would be a legitimate alternative to a twin turbo 350. I definitely want fuel injection, and shooting for 600+ hp with decent street manners. Thanks for the help!
I have been looking at big blocks as an alternative to my twin turbo LT1 idea, and have found some pretty interesting buildups. Of particular interest was an article in the August 2003 issue of Hot Rod magazine. On page 18, it talked about a guy named Pete Aardema that took an aluminum BBC and bolted on a set of Porsche V8 DOHC heads. It's fuel injected and 440 CID. It makes 550 ft-lbs. at only 2500 RPM! Anyone else ever heard of this being done? I am interested in building a big block (probably from a Merlin aluminum block), but I must admit that I am ignorant in the big block arena. Can anyone offer suggestions as to the approach to building a BBC, parts that are of good quality, etc? I am just wondering if it would be a legitimate alternative to a twin turbo 350. I definitely want fuel injection, and shooting for 600+ hp with decent street manners. Thanks for the help!
09-29-2003, 05:05 PM
#2
Melting Slicks
Re: Big Block options? DOHC? (Last Ride)
600+ horsepower with decent street manners is almost an oxymoron. If you want decent street manners, you should be more concerned about torque rather than horsepower. The more torque you can get at as low an RPM as possible is the general rule of thumb for decent street manners.
That being said, it's hard to beat the new Chevy 502 crate motor. Gobs of low end torque, and close to 600 lb-ft of torque without much trouble, and on pump gas. Problem is, they don't make an aluminum 502 that I know of. You can still get an iron big block Chevy close to the weight of a small block with prodigious use of aluminum components, such as heads, intake, water pump...things like that.
I have heard that the ZL1 has been reborn in limited numbers, but with 454 cubic inches instead of 427. It's not cheap, and I'm sure the line is long, but you should probably look into it on GM's Performance Parts website, or perhaps Scoggin Dickey's site.
Anyway back to the engine formula. I'd suggest oval port heads for your street friendly engine. A recent article compared oval ports to rectangle ports, and at all points below 6500 rpm, the oval port heads were vastly superior. If you were going all out for a racing motor, with pure top end, then sure, the rectangles would get the nod, but why throw away free torque over bragging rights? Let the other guy brag all day that his big block has the hugest most wildly ported rectangle heads. Talk's cheap, torque is what pulls ahead.
For the fuelie set up, once again, check out GMPP or Scoggin Dickey and see what they have. The 502 has a nice FI set up which resembles the old L98, but larger. It's kind of a tuned port type set up, and that type of fuel injection (or a tunnel ram type configuration) will probably work best for you.
If you really want your cake and eat it too, and are like me...just have to have your rpm's for those "special moments", then drop compression down to 8.5 and run a whipple charger or a nice size centrifugal supercharger. You'll still have nice torque, the natural talent of big blocks, but you'll also have some really gut wrenching midrange and top end.
Just don't expect good gas mileage. Not with a performance big block!
[Modified by Bearcat, 3:08 PM 9/29/2003]
That being said, it's hard to beat the new Chevy 502 crate motor. Gobs of low end torque, and close to 600 lb-ft of torque without much trouble, and on pump gas. Problem is, they don't make an aluminum 502 that I know of. You can still get an iron big block Chevy close to the weight of a small block with prodigious use of aluminum components, such as heads, intake, water pump...things like that.
I have heard that the ZL1 has been reborn in limited numbers, but with 454 cubic inches instead of 427. It's not cheap, and I'm sure the line is long, but you should probably look into it on GM's Performance Parts website, or perhaps Scoggin Dickey's site.
Anyway back to the engine formula. I'd suggest oval port heads for your street friendly engine. A recent article compared oval ports to rectangle ports, and at all points below 6500 rpm, the oval port heads were vastly superior. If you were going all out for a racing motor, with pure top end, then sure, the rectangles would get the nod, but why throw away free torque over bragging rights? Let the other guy brag all day that his big block has the hugest most wildly ported rectangle heads. Talk's cheap, torque is what pulls ahead.
For the fuelie set up, once again, check out GMPP or Scoggin Dickey and see what they have. The 502 has a nice FI set up which resembles the old L98, but larger. It's kind of a tuned port type set up, and that type of fuel injection (or a tunnel ram type configuration) will probably work best for you.
If you really want your cake and eat it too, and are like me...just have to have your rpm's for those "special moments", then drop compression down to 8.5 and run a whipple charger or a nice size centrifugal supercharger. You'll still have nice torque, the natural talent of big blocks, but you'll also have some really gut wrenching midrange and top end.
Just don't expect good gas mileage. Not with a performance big block!
[Modified by Bearcat, 3:08 PM 9/29/2003]
10-01-2003, 02:35 AM
#3
Melting Slicks
Re: Big Block options? DOHC? (Bearcat)
FYI, I had trouble finding either website that I mentioned above. Try GM Goodwrench. I've found several links there.
The 502, by the way, is on sale for $6800 bucks for the long block. This is with 8.75:1 compression, so it's immediately blower-friendly. I'd suspect cast pistons though, so keep boost down to 6 pounds or so. And expect amazing torque.
Not bad, $6800 bucks. Try building a performance big block as cheap as that!
The 502, by the way, is on sale for $6800 bucks for the long block. This is with 8.75:1 compression, so it's immediately blower-friendly. I'd suspect cast pistons though, so keep boost down to 6 pounds or so. And expect amazing torque.
Not bad, $6800 bucks. Try building a performance big block as cheap as that!
