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Steve1968LS2
07-16-2008, 06:39 PM
As a possibility to power my Track Rat project... :naughty:


I was Turn Key Engines building the 427 LS engine for the Project American Heros Camaro and saw they have PALLETS of 5.3 ALUMINUM blocks. Litterally dozens of them.

So we started chatting and decided it would be cool if we could come up with a budget minded high-reving 302ish displacement engine.

Would be super lightweight and to keep the cost down would use all GM stuff except maybe the pistons (since we would bore the block).
4.8 crank and rods then top it off with an LS6 intake. If we choose the cam right I'm thinking 500hp isn't out of the question.

I've been considering a 5.3 but hated the idea of the heavy iron block.

Thoughts?

skeeters65
07-16-2008, 06:41 PM
Are most 5.3 blocks steel or aluminum??

Which cars came with which??

Thanks

WS6
07-16-2008, 06:42 PM
Not bad. There way a company that built a 302 oh 8 years ago now. M something was their name and they put it in a 4th gen trans am racer.

I'd just build the snot out of the AL 5.3 since people don't think they can spin or make power. Modern 327 if you will. There is not reason a 5.3 won't spin to 7k or higher if you want to push it.

PonchoJohn
07-16-2008, 06:43 PM
Interesting idea.
I'm not super knowledgable on the LSx stuff, but isn't the 4.8 crank stroke and rod length different than all the rest?
If so, wouldn't the piston be pretty TallxWide?

WS6
07-16-2008, 06:43 PM
Are most 5.3 blocks steel or aluminum??

Which cars came with which??

Thanks

Most are cast iron but they started making aluminum ones in quantity with the Impala SS, Monte Carlo SS, Buick Rainier, and now trucks have aluminum 5.3s. I think those started in 05 or 06 though.

WS6
07-16-2008, 06:45 PM
Interesting idea.
I'm not super knowledgable on the LSx stuff, but isn't the 4.8 crank stroke and rod length different than all the rest?
If so, wouldn't the piston be pretty TallxWide?

Correct 5.3, 5.7, and 6.0 all have the same rod and crank dimensions. 4.8 has smaller crank.

You could get out of hand and make the engine very over square (bigger piston than stroke length) but those engines love rev's. If the block and components can handle it, it's not a bad way to go.

Steve1968LS2
07-16-2008, 06:48 PM
Not bad. There way a company that built a 302 oh 8 years ago now. M something was their name and they put it in a 4th gen trans am racer.

I'd just build the snot out of the AL 5.3 since people don't think they can spin or make power. Modern 327 if you will. There is not reason a 5.3 won't spin to 7k or higher if you want to push it.

Well a company in the midwest did it for GM called Westech. It was in a pewter 4th gen Camaro.

I know I could just do the 5.3 but I was trying to think of something different.

I will use the 5.3 aluminum block... the question is how.. hmmm

Steve1968LS2
07-16-2008, 06:51 PM
A 4.8 crank, rods and pistons would make something like a 297cui if you went 60 over it would be around a 305-307

That's just off the top of my head, I would have to crunch numbers.

Excited now that I found some 5.3 alum blocks. I think budget wise it could be a real doable deal.

WS6
07-16-2008, 07:04 PM
check it out Steve. I found this while googling info on the 302 Trans Am I mentioned.

http://www.pro-touring.com/forum/showthread.php?t=20495

Van B
07-16-2008, 07:17 PM
Well a company in the midwest did it for GM called Westech. It was in a pewter 4th gen Camaro.

I know I could just do the 5.3 but I was trying to think of something different.

I will use the 5.3 aluminum block... the question is how.. hmmm

The "other" Westech, just down the road from me in Silver Lake, WI. I think they built it for Power Tour a number of years ago.

I like the 302 idea.

compos mentis
07-16-2008, 07:28 PM
Andrew B and I suggested to you several months ago the 4.00" x 3.00" setup like the Daytona Prototype cars use.

Another forum member here knew I was interested in a high winding destroked LS motor. He was talking to Mast Motorsports about it and wrote me this.

'I just got off the phone with the guys over at Mast. There ECM offers a ton of stuff I've been looking for in the tuning setup, while maintaining almost all of the GM driver friendly gas mileage bits as well... The VVT is fully variable for the 62 degrees of camshaft movement. They've been focused on big power and flat torque arks with normal RPM's, but he told me they've never gotten a motor to use the full 62 degrees of adjustment in the camshaft. 10,000 RPM in a streetable LS motor ...'

Gordz32
07-16-2008, 07:40 PM
Dooooo It. Theres nothing like a super high winding small block. There hasn't been much done by way of the LSX crowd and for you ( and your resources) It would def. be something different. Oh and maybe slap a turbo on on there for extra coolness. :6gears: :yeah:

Steve1968LS2
07-16-2008, 07:41 PM
Yea, but I was having a hard time finding an alum 5.3 that wasn't stupid price. Now I have a plethora of virgin blocks, so the idea is once again alive. :)

compos mentis
07-16-2008, 07:56 PM
Another guy who works with engine builders doing these smaller LS motors wrote me this.

"There are probably used (billet) cranks available for a reasonable price. They tend to use fresh rotating parts for the 24 hour race, even though I don't ever
recall hearing of a crank failure."

slowcamaro
07-16-2008, 08:05 PM
my friend plans on doing similar for a CP autocross car where hes limited to 310 cubes(i think) before taking a weight penalty.

andrewb70
07-16-2008, 09:19 PM
http://www.westechauto.com/

The 5.3L bores are just too small. Stephen, if you're going to do this, do it right. LS2 4" bore block, billet 3" stroker crank. This is a track car. The engine needs to live!

Andrew

P.S. Answer your PMs...LOL

Damn True
07-16-2008, 10:10 PM
I like the idea.

Andrew, why is the bore such a factor?

EFI69Cam
07-17-2008, 05:04 AM
I like the idea.

Andrew, why is the bore such a factor?



On the top end a bigger bore allows bigger valves and less turbulence from the air hitting the cylinder wall.
The over square concept that ws6 mentioned is when the bore/stroke ratio is >1 4/3 is the b/s for the orginal 302.
A shorter stroke is supposed to rev better as it allows a longer rod and less friction from piston movement.

With the deck height of the LS1 block easily allowing a 6.2 rod and modern connecting rods and cranks it is easy to build a shortblock were the rev limit on the reciprocating assembly is way higher than what the valvetrain can handle reliably. In other words you are leaving power on the table not putting in the longest stroke crank you can fit. Building a 302 would be cool from a nostalgia standpoint but fairly useless in terms of efficient use of build dollars.

Tony_SS
07-17-2008, 05:12 AM
Steve I like the idea.. Doing more with less is always interesting.

Phil at BRP HotRods seems to know a great deal out the LS series - maybe he will chime in.

WS6
07-17-2008, 05:38 AM
MMS, Morgan Motorsports was the company that built the 4th gen Trans Am racer that had a 302 in it that I was referring to. It just so happens that it was a white with single blue stripe Trans Am just like the 70-72 TA. I don't even know if MMS is around anymore.

Steve1968LS2
07-17-2008, 05:53 AM
http://www.westechauto.com/

The 5.3L bores are just too small. Stephen, if you're going to do this, do it right. LS2 4" bore block, billet 3" stroker crank. This is a track car. The engine needs to live!

Andrew

P.S. Answer your PMs...LOL

5.3 alum blocks have very thick sleeves and can easily be bored 60 over. In fact I've heard they can be made into a 5.7 but I would have to confirm.

Again, I want to try something different. Where's the story value if I just do whats been done a bunch. If it fails on the dyno I can always stroke it up in displacement. That's why I'm stating the engine portion of the car early, so I have time to tweak the plan.

andrewb70
07-17-2008, 05:56 AM
Andrew, why is the bore such a factor?

What EFI69 said. Another factor is that a larger bore provides a greater area against which the expanding gases of combustions can act against.

The problem with stroker cranks in LSx engines is that the cylinder liners are too short. One of the "dirty little" secrets that people rarely talk about. With 4" or more stroke cranks only about 1 inch of the top of the piston is supported by the bore at BDC. While these engines are all the rage, I'll pass, unless the engine is based on an LS7 block or resleeved.

Andrew

andrewb70
07-17-2008, 06:07 AM
5.3 alum blocks have very thick sleeves and can easily be bored 60 over. In fact I've heard they can be made into a 5.7 but I would have to confirm.

Again, I want to try something different. Where's the story value if I just do whats been done a bunch. If it fails on the dyno I can always stroke it up in displacement. That's why I'm stating the engine portion of the car early, so I have time to tweak the plan.

LOL...You probably heard it from me. I got a 5.3L aluminum block engine in the fall of 2006. It was going to be a budget turbo engine for the RX7. The sleeves on a 5.3L have the same O.D. as the 5.7L sleeves. So yes, you can easily have the 5.3L bored and make it into a 5.7L LSx. What is so different about that?

Here are some pictures from the disassembly:

http://www.pro-touring.com/%7Eandrewb/CRW_1613.jpg


http://www.pro-touring.com/~andrewb/CRW_1621.jpg


http://www.pro-touring.com/~andrewb/CRW_1626.jpg


http://www.pro-touring.com/~andrewb/CRW_1645.jpg


http://www.pro-touring.com/~andrewb/CRW_1654.jpg



Andrew

Steve1968LS2
07-17-2008, 06:26 AM
LOL...You probably heard it from me. I got a 5.3L aluminum block engine in the fall of 2006. It was going to be a budget turbo engine for the RX7. The sleeves on a 5.3L have the same O.D. as the 5.7L sleeves. So yes, you can easily have the 5.3L bored and make it into a 5.7L LSx. What is so different about that?

Andrew

There's nothing different about that. I was just making a point about how thick the sleeves are on an alum 5.3 block :)

I could just build it as a 5.3 which would be pretty much a modern all aluminum 327. Hell, with my resources I could build it both ways just for giggles and education.

Like I said, if I just build what's been done a dozen times then how much value would that story have? I would rather experiment for you guys. So, we will build two engines. On a standard stroke 5.3 and the other a deStroked 5.3 with an overbore to get it to the 302 range. Thoughts?

Steve1968LS2
07-17-2008, 06:27 AM
By the way Andrew.. you should do freelance work in regards to tech stories. You take better technical photos than most of the freelancers I work with.

andrewb70
07-17-2008, 06:35 AM
By the way Andrew.. you should do freelance work in regards to tech stories. You take better technical photos than most of the freelancers I work with.

LOL....Thank you...Those photos were destined for a tech article, but the build never happened. You just gave me a great idea. still waiting for an answer to your PM...:bicycle:

Andrew

trapin
07-17-2008, 07:56 AM
I like the idea of the 5.3. There are so many of them out there that are available. It's time we found out what these little mills are capable of.

I have a 5.3 in my truck and I think for what it is it runs like a monster. I'd love to see what a cam, intake and exhaust would do for it.

Rick Dorion
07-17-2008, 08:30 AM
Didn't Jeff Smith (forgot which mag but probably CHP) build a supercharged 302 a long time ago for good mileage and insane power on a GenI? Now we could have a LS 302 and get it all.

Steve1968LS2
07-17-2008, 08:52 AM
Didn't Jeff Smith (forgot which mag but probably CHP) build a supercharged 302 a long time ago for good mileage and insane power on a GenI? Now we could have a LS 302 and get it all.

Yep, a destroked 302 with a turbo would be super cool. Just not sure I want to deal with a turbo (and it doesn't really fall in the budget catagory).

Damn True
07-17-2008, 09:08 AM
Didn't Jeff Smith (forgot which mag but probably CHP) build a supercharged 302 a long time ago for good mileage and insane power on a GenI? Now we could have a LS 302 and get it all.

That was a neat engine.

Rubes
07-17-2008, 09:09 AM
Yep, a destroked 302 with a turbo would be super cool. Just not sure I want to deal with a turbo (and it doesn't really fall in the budget catagory).
I've been considering this for a while...I got a pair of T-66's on the shelf waiting for something to go into. as if I need something else to do..thanx alot Steve:poke:

DJW32
07-17-2008, 09:31 AM
check it out Steve. I found this while googling info on the 302 Trans Am I mentioned.

http://www.pro-touring.com/forum/showthread.php?t=20495

Nineball did not like my idea of a de-stroked ls motor. After I figured the budget for that motor...I throw the idea away

DJW32
07-17-2008, 09:33 AM
Like I said, if I just build what's been done a dozen times then how much value would that story have? I would rather experiment for you guys. So, we will build two engines. On a standard stroke 5.3 and the other a deStroked 5.3 with an overbore to get it to the 302 range. Thoughts?

Do it!

Alan66ss
07-22-2008, 04:24 PM
Steve,

I have been thinking of doing this with my LS6. I would definitly be interested in the article. So go for it.

Alan

wedgehead
07-22-2008, 07:11 PM
We will keep an eye on this thread as we are going to put a 5.3 in my son's 78 T/A. The engines are easy to find cheap. Just priced one at a local yard for $600 48000 miles. I am looking at a 16 year old doesn't need LS1 power and I am hoping the 5.3 will get better miage as this is going to be his DD. He can change to a bigger engine later as all the adapting to the car will be done.