1BDHWK

iTrader: (18)

It depends on your definition of N/A. If you are doing a basic N/A build, definitely go with aluminum if it's in the budget(hell, an AL block with do well with a normal shot of juice). If you are looking for a high hp/high rpm N/A build, I would look at an iron block to help prevent cylinder wall distorsion.

WKMCD

iTrader: (2)

It's only money...

It's going to be hard to get an "honest" 550RWHP out of a 403/408 without a single plane intake and a good size cam. I think you have more decisions to make than aluminum or iron.

BTW: I vote aluminum.

RENE'S RAGE

iTrader: (96)

That's what I was getting at. 550rwhp would be easier with a 416. Not much more for the LS3 block than the LS2 block.
You don't have to settle, just save.

02sslayer

iTrader: (4)

the 402 sounded good at first, but a larger cube ls3 is sounding better. so now im kinda thinking about a 418 or 427. im gonna go compare some prices

02sslayer

iTrader: (4)

i went on texas speed's site and did a camparison

these comparisons are for shortblocks.

402=$4100
408=$3850
418=$4900
427(ls3)=$5500
454=$6500

im kinda thinking that the 418ci is the most appealing for price and performance. however the 408 is also a great bargain for a budget build.

fatmat80

Depends on the purpose of the build. Depending on purpose of vehicle weight over the nose can be a problem. I would go with the 402 with the amountof info you have given. If I were you I would go a little bigger if you are staying NA like a 416 or 427.

Stage7

iTrader: (1)

Always go for the lightest and biggest that fits your application and budget. Ie: aluminum and max cubes you can afford. And have the right builder build it.

Gordon0652

iTrader: (4)

Lets stop talking about engine size for a few posts and lets talk about goals and the idea behind the build.
After that lets talk about budget.

02sslayer

iTrader: (4)

ok well my goals are to have a big motor that puts down about 550rwhp. it will be a street car with a good amount of track time. i also want to go with the b igger motor for more torque, as i will probly want to use a good size cam. i want to put afr's on whatever engine i choose.

Chevy2169

I'm in the same boat as you ^ right now. I really want to go with a 427 from va speed on a 20k budget. So I'm very interested in what you guys think as well.

kevin kuether

iTrader: (1)

When I was deciding what size motor to build I called some places that deal with mostly drag race setups. Same answer from all was the weight gained by an iron block will not hurt because you too much horsepower from cylinder wall distortion in an aluminum block. I was told the iron block will actually be faster. That is why most high horsepower engines still use a cast block. I'm sure this will turn into a big debate but I got the same answer every time so I went cast and will lose the weight somewhere else.

kevin kuether

iTrader: (1)

Sorry for typo. Should say lose too much horsepower.

Gordon0652

iTrader: (4)

You said big motor, so i am guessing with a bigger motor and making that power level you are going to stay N/A.
I would suggest a 416 LS3 because it is AL and will make that power with a nice budget.
If you want to really spend some money i would say LS7 427 or 440, that will make more than your power level.

Why AFR cylinder heads?

HoLLo

iTrader: (17)

I vote 402. Unless the iron block was practically stolen. I would love an aluminum 400+ci motor

02sslayer

iTrader: (4)

i am staying N/A, i want to go with afr's because if im gonna do this build i wana do it right. and afr makes some of the best heads.

ive been told that you cant run an ls7 motor in a 4th gen fbody cuz of the dry sump. if im gonna go real big i would go 454 all the way

Gordon0652

iTrader: (4)

First AFRs are good heads, but there are much better heads out there. (PI, WCCH...)
But then again its all based on opinion... but not really.

Also i am building a 440 LS7 in my T/A, you do not have to use a dry stump with an LS7 if it's built right, but you can in any car basically.

454s are alot of money if "done right"

You need to do a lot more research - a lot more.

Orange Juice

iTrader: (3)

Get in touch with a good builder and start planning, remember with the bigger cubes the power just comes that much easier. There is no problem using the ls7 block without the dry sump and with the larger bore compared to the ls3 they tend to let the motor breath better. As far a cost go my long block was very much a budget build, What gets expensive is upgrading your intake, fuel delivery, headers and cooling system. Not to mention transmission and rear end.
AFR heads were what I was originally going to go with because I had the intake set up for cathedral port heads, but my builder recommended the TFS 235's and they seem to be working alright.

litle88

iTrader: (20)

I know TFS heads are good because I had a set and I hated the fact that I milled them to 60cc's because now I cant use them on my 416 build. But I ran into the cnc'd and ported Ls3 heads from Lingenfelter that are a work of art and the flow numbers look about even with the other porters on here, I also saw ALOT of guys on the camaro5 site and they are making over 500 hp with decent sized cams and stock cubes. For 1600 assembled and shipped with the hollow intake valves and inconel exhaust valves, you cant beat it. So now I have to save for the FAST Ls3 intake and TB. I too am on a quest for 550hp minimum

COPO9560

If you use your LS1 block as a core, ERL's Superdeck can be had in 427 for about $6500. This includes billet caps, sleeves, ARP studs and high quality forged internals. Considering all your covers, sensors, wiring etc will fit when you get it back this might end up being lower cost than one would first think. The larger bore on sleeved engine will allow heads to breath better than the LS3 version as well.

02sslayer

iTrader: (4)

i couldnt agree more, i do need to do alot more research. thats why i dont plan on getting the build started for a couple years. as far as 454 gos, that would be my number one choice but money is really an issue for that. 6500 just for the shortblock, and i can acheive my goals with less than a 454.