Aluminum 427 Small Block Gen I
 

Ok, I have a question for those guys out there using a 427 SBC GEN I Block Iron or Aluminum. I am thinking about assembling an Aluminum 427 using either a Dart or World Block. This engine will be used as a daily driver and be taken on long trips, hopefully Power Tour. Can you guys give me some pros and cons to these blocks? I spoke with both tech departments and they both had good points to there products. The Dart seems to be the better block, however the Motownlite seems to be closer to a stock 400, which in the end could prove to be a better deal. The list kind of went like this.

Sorry Scott for the crude table.

.................................Dart............. ..........................Motownlite

Different Deck Heights....Yes.................................... ...No
Stock Oil Pan set up.......No (wide spread rail)................Yes....(Stock)
BBC Cam Core...............Yes............................ ...........No.....(Stock)
Stock Oil Filter..............No............................ ...........Yes.....(Stock)
Square Block................Yes.......................... .............No
Intake Height Stock.......No.................................... ....Yes....(Stock)
Stock Height Distributor..No................................... .....Yes....(Stock)
Special Head Studs........Yes.................................. .....No
Special Custom Cam.......Yes..................................... ..No Small Base Cir
Special Timing Gear........Yes................................... ....No
Weight.........................95 lbs...................................100 lbs
Billet Steel Splayed Mains.Yes......................................Yes
Material:.......................355-T6 aluminum....................357-T6 aluminum
Sleeve________________.250_______________________. 250" @ 4.155 bore
Raised Cam....................Yes........................ ..............No
Max Cubic Inch...............455 (4.185 x4.125)................434 (4.155 x 4.00)
Special Ribbing................No......................... ..............Yes

The thing that amazes me about these specs neither company thought about changing the lifter bores over to the new style (tall style) so you can use the new design lifters that are cheaper then the Retro Style lifters.

Please let me know your opinions and experiences. Thanks Guys! :D

every machinist and engine builder I've met prefers the Dart blocks over the World stuff. Nicer machining, less casting flash, better quality, and on and on.


Jody

Yea Jody that's what I've heard too, but it seems like it needs everything. Oil pan, special cam, special head bolts, special push rods ect...

Of those 2 blocks a would recommend a Dart,my personal favorite is Donovan.

Keep your tolerance tight so when it warms up to operating temp it's not to loose and rattle to death.

Has long as it's a stock spec block,everything will bolt on it,usaully when getting into the tall deck blocks is when the cam tunnel gets raised and the spread the pan rail out.

Donovan makes(used to sure to be honest) block that will except all the stock hardware

Hows the pricing of the Donovans?

About the same 3k give or take.I haven't priced a standard block in awhile.

Have you considerd Brodix?

You know I haven't. I need to look at them too. I seem to forget there are more then just 2 companys making thoses things.

Warhawk
 

Does it have to be Gen I?
World makes an aluminum LS series block called the Warhawk that accepts a 4.125" bore and costs less than the Gen I blocks. About $2K - $2500

Sorry, I confused the World aluminum block w/ GMPP's iron block. The World Block is $4K. Forget I was here. :_paranoid


Mal

The more I read on the net about aluminum the less I like it. I still want a SBC 427 though.

You can buy a used LS1 aluminum block for $200. :D

Have you thought about LS1-2 motors for your "street" car?? Same power, 1/4 the cost. Just an option??

Where?! :willy:
I just bought an iron LS1 block for $75. I would have jumped all over the aluminum one for $200. Lowest I have seen is for $500 and that was for a 5.3. :(


Mal

The best place are

Donovan
Brodix
Dart


I haven't used a Brodix block yet,put I use alot of there heads,and I have never seen any junk.

I have seen boat loads of bare ls1 bare blocks sell for the $200 range in the last couple years. This one below had much more with it. You can buy complete turn key motors with a trans for less then a Dart block, that's not bad for a block good to well beyond 1000 hp!! :D


http://cgi.ebay.com/ebaymotors/LS1-C...58102523QQrdZ1

If World products didn't make that Warlock I think it would be great,but I have seen to much WP junk.


I,m waiting on the new GMPP LSX steel block it will go to 511 inches,

Really an aluminum block on the street isn't needed,It's cool to say it's all aluminum,but a steel block will be useless.

If you were doing a BBC an aluminum block on the street would be worth to drop a 150 pds.

If you go the LSX route,a LS2 is the way to go, the casting are better than the LS1 block

An aluminum block can also be repaired, that is one big advantage!!

Yeah,maybe,many can't be saved,but if it's a street only car it shouldn't be blown up that bad.

LS1 blocks are bad about be junk when they blow up hard.i have only seen one or 2 be fixed when I sent them off

6 of 1, 1/2 dozen of another.

This type of talk doesn't flatter the aluminum block at all.

http://speedtalk.com/forum/viewtopic...2146&highlight

The Thrasher has a GM iron rocket block 427.

Here is a Brodix........
http://img.villagephotos.com/p/2005-...0/IMG_0826.JPG

That is VERY nice. I like it. Is everything standard on that as far as Distributor height intake height oil pan rail ect..? :D

that is beeyooteefull :hail:

Yes,including stock deck height but it's not a 427.

So what size is it? A 434 or bigger?

No it's 373,destroked 400.It is a twin turbo motor so no real need for big cubes.

You can easily make a 427" LS2 motor with an aluminum block. That will handle all the power you can throw at it. On top of that, an LS2 head with a little porting flows better then out of the box 18 degree heads...plus it's fuel injected!! :D

Do what LS2 out flow 18's,Ls2's won't flow 350 cfm ported,I have set of Brodix 18's that out of the box flow 350 cfm,no port work out of the box.

The Brodix 18's do not flow 350 out of the box, suppose it depends on whos flow bench. All would have to be done on the same bench.
My Dart 18's flowed 330/260 @ .700 lift out of the box. My TEA ported LS1 heads flow 317/255 at only .600 lift. That is as much or more then my $4000 Dart 18 degree heads, with a factory $200 set of heads and $1200 worthe of valves and porting!


LS6 heads with porting 346/270 @ only .600 lift on a cheapy factory head!!


YOU CANNOT BEAT THAT WITH A STICK! :unibrow: :willy:

Flowed them today at 700 lift they were 350/270.

So you gotta admit that the ls1 heads flow big time at only .600 lift for a head with a total investment of less then $1500 bucks!!

That's what I LOVE about LS1's! :yes:

They flow good,not bad for a street head. I have seen some killer LSX heads that flow low 400's.I did a friends Ls6 heads acouple years ago and they flowed 390 at 650.

I was just pointing out that while it is possilble to out flow out the box heads,it's going to take quit abit of port work on stock heads,Brodix heads IMO are the best for out of the box performance.and are the closet to advertised flow #'s I have seen.

Here's a Brodix block 427 we're doing for a 3rd gen Camaro. Standard everything on the block except the rocket block style oil pan. Off the shelf parts inside except for reduced base circle cam. Brodix gives you alot of options.

What's their pricing on a block?

Tom, why a reduced base circle, don't they raise the cam like a rocket block?? What is the deck height?

I think it was in the $4500 range. I'm not at the shop so I don't have the exact price.

We ordered standard cam location and standard deck to work with parts he already had.

I just checked online and it lists at $4399.

I paid $3995 for mine.

That sounds like a good price. I'm still torn though on whether to do an aluminum or not though. Everyone is saying that there can be a horsepower loss for the first couple of builds because of the sleeves moving around inside the block. Jonny does the car handle a ton better or do you not notice it?