Build me a motor!!!

[shortbed70]

Now that I have your attention, give me your ideas on a high winding sb...
I'm thinking 5.3 LS
Or 350 block, 307 crank, 327 pistons and some compression!!
Now this isn't for a truck or the street but I would like it to run on 91 but race fuel and spray aren't out of the picture... I'm on a budget too...
I have to buy the LS but have some parts for the other motor...

5.3 carbed with a 100 shot?
331 11-1 sbc /na

Going in a 95 camaro..
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[Super73]

You are leaving a lot of power on the table with a 5.3 bore spacing. You can get the same rpm's from an LS3 block and the much better 4.08" bore spacing.

Heck, you can even run 8,000-8,500rpm with a well prepped 4.0" crank.

Why limit yourself to a 5.3 liter when you can build a 418" motor with the above specs?


The thing you need know is more about the heads, cam and intake. A Nice set of AFR 245's with a good sized solid roller and single plain intake will get you there.


Oh wait, you are on a budget.. That just killed your high RPM rever. You are better off sticking to a hyd motor and 7,500 rpm. With that you can find a set of good heads for a 3.905 bore. That would be your best budget option.

[djracer]

Ok Shon you may have lost him. You lost me. LOL I know you know the Ls stuff does he need to start with a 6.0 liter motor or what?

[shortbed70]

Originally Posted by Super73

You are leaving a lot of power on the table with a 5.3 bore spacing. You can get the same rpm's from an LS3 block and the much better 4.08" bore spacing.

Heck, you can even run 8,000-8,500rpm with a well prepped 4.0" crank.

Why limit yourself to a 5.3 liter when you can build a 418" motor with the above specs?


The thing you need know is more about the heads, cam and intake. A Nice set of AFR 245's with a good sized solid roller and single plain intake will get you there.


Oh wait, you are on a budget.. That just killed your high RPM rever. You are better off sticking to a hyd motor and 7,500 rpm. With that you can find a set of good heads for a 3.905 bore. That would be your best budget option.

Lol!!!

Originally Posted by djracer

Ok Shon you may have lost him. You lost me. LOL I know you know the Ls stuff does he need to start with a 6.0 liter motor or what?

I have a buddy says he could find me a 5.3 for under $500 but idk about the 6.0. I was actually wanting a 6.0 but don't know if I can get one or not.
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[Super73]

I was recomending you start with a new LS3/L92 block ($1400ish). They come from the factory with a 4.065" bore and can be taken out to 4.08" safely.

Here are factory bore specs:
4.8 / 5.3 = 3.78"
5.7 = 3.899
6.0 / LS2 = 4.0"
LS3 / L92 = 4.065"

The problem with the smaller bore blocks is they tend to shroud the intake valve and do not allow for maximum air flow. With a NA motor it can reduce power fairly dramatically. You are much better off starting with a 6.0 block, it's cousin the LS2 which is an alum block or its big mean uncle, the LS3 / L92 in alum.


If it is RPM you are after, a stock 3.622 crank will go upwards of 8,500 when balanced. Even the Callies 4" cranks will go 8,000+ when balanced. All I am getting at is don't limit yourself to a small cubic inch motor thinking you can't push a bigger motor to the same rpm.

To get the RPM, you are going to need the heads and valvetrain to do it. I would feel safe spinning a hyd cam to 7,500 (I have heard rumors of the CTS-V class racing taking hyd rollers to 9,000 but I don't know the truth behind it). If your after 8,000+ rpm, you are probably going to want a solid roller set up. Be prepared to open your wallet.

I hope that helped..

[shortbed70]

Well I'll tell you this, I'm LS stupid! I haven't played with these motors at all so when I wanted a high winding motor I was referring mostly to the gen 1 I'm used too with the destroked high comp like the old 302 sbc. If I go LS its going to have to stay mostly stock due to buying cost and changing from gen 2 to LS underhood...if I go LS probably put a cam/head combo on it and be done.. Thanks for the info now I just need to start getting parts...
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[Super73]

If you are staying NA with an LS, find a 6.0 block. It's worth the extra few hundred dollars for the power gain you will see, let alone the drivability. 5.3 to 6.0 = 13% increase in cubic inches.

The added inches + Unshrouding of the valve + Ability to tame the same sized cam (or run a bigger one) = Much happiness!!

[shortbed70]

Ok I'm on the hunt to see what I can find local... Thanks guys... Hey super73 how's your truck going?
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[Super73]

Still at the chassis shop, but it is getting lighter and going to go faster