Let me hear about your bracket race combinations

www.folkracecars.com. Check with them.

I run a 408 LS in my 77 Cutlass, Made 672 HP at the Crank. LS3 Heads, Victor Jr, 850 Holley on 110 octane. 12.5:1 Compression. What else do you want to know?

quote:

Originally posted by Racer442olds:
I run a 408 LS in my 77 Cutlass, Made 672 HP at the Crank. LS3 Heads, Victor Jr, 850 Holley on 110 octane. 12.5:1 Compression. What else do you want to know?

672hp at what rpm?
What was peak torque?
What does it run in 1/8'?
Race weight?
Rear gear?
Stall Rpm?

672hp at what rpm? 6600
What was peak torque? 581 at 4900
What does it run in 1/8'? 6.80s de-tuned due to suspension not being up to par. (went from 7.70s to this combo on a 9" tire. still learning)
Race weight? 3600lbs
Rear gear? 4.10
Stall Rpm? 5000?

Call Luke Siebert at Siebert Performance in Topeka KS. 785-286-6813. He specializes is LS engines

Wow 442,I'm surprised your dad let you put a Chevrolet motor in that lol

quote:

Originally posted by steely:
Wow 442,I'm surprised your dad let you put a Chevrolet motor in that lol

Scott I Assume? Dad went to a 468 BBC years ago in his 68 442. Last year was the first year on the LS powerplant in my 77. I had run a 455 Olds for the last 5 years

408 LS3 heads 12.5 compression 1050 dom. carb P/G 180 s/g gears 5.13 rear gear 31x14 Hoosier F/B leave at 3000 5.82 1/8 mile 118 mph 2620 lb with driver . Mark Sullens E-85 carb

my research to this point;

[NOTE: bracket race engine, no small tire, no grudge, no turbo, no NOS] a bracket race package capable of consistent and winning performance.

*With the above explanation, I am finding the cost about the same as a first generation small block.
*One thing I like, an LS3 aluminum factory block can be bought new for about $1600.00. This can make a good package that is about 80 pounds lighter than the first gen.
*The LS platform popularity is growing and the architecture of the LS has some advantages. Raised cam, accepts 4" stroke without modification, lots of parts on the market.

After 50 years of building and racing the original SBC, I have decided to make the change. I plan to build an LS3 aluminum block with LS3 worked heads. In addition, it will be carburated with the front mounted distributor option. Thus, allowing me to make some steps toward the modern while clinging to my carb.and distributor

Keep us informed. I know the LS engines get a bad rap for the following:

Cam bearing problems.
Oiling system problems above 7000.
Thrust bearing problems.
Stock roller rocker problems.

Curious to see how you deal with the above. Certainly there are people that know, maybe they will talk about it now, but years ago they didn't. Was like talking to fast Stock and Super Stock guys, they weren't giving-away any secrets.........

I was in the midst of tuning a newly built 406 LS, had about 200 miles on the engine when the cam bearings starting to seize on the street. Nothing special engine, made about 650hp at the time. That engine builder obviously didn't know the secrets to making those bearings stay-still.

Mike, I do not want to learn these engines by experiencing their weak points. It too expensive and too much time lost for an old man. I appreciate your feedback and will make every effort to avoid the pitfalls.

"Hopefully" enough LS engine are being raced successfully and the problems you experienced have been corrected.

Larry, I think Jeremy Falkenbach runs an LS motor in hiw white El Camino. You may want to check with him.

An L33 style engine that came in 05-07 GMC Sierra's and some other full size trucks is an all aluminum 5.3 option for the LS. It should be a much cheaper option than an LS3. I think a few guys around here have ran basically junk yard bottom ends with a bigger cam and alcohol carburetor - going low 6's in the 1/8 with a good amount of success.

What advantage are you hoping to have with the distributor over coil on plug?

no advantage with distributor and I may soften on my stance.

Larry, from what I have been told, if you bore and clean the block obviously the cam bearings have to be replaced. There is, or there was, something special about installing those cam bearings.

Not sure if it was just an issue with the 350-sized aluminum blocks, or if it included the cast iron 6.0 blocks and the newer 5.3 and 6.2 blocks......

Check-around. Seems like the people that were not complaining never touched the engine, only changed the cam, heads, and upgraded the rocker trunions or simply went to a shaft system, and kept the rpm below 6500.

I have seen really good success with the iron LSX block. Amazing the power on 93 unleaded, but the cost is through the roof just to run cheap gas.

As you have found, to spin a SBC to 7500+ making 700+hp, it is basically a wash between the two platforms.

I would love to do an engine like you are contemplating, but I too don't want to be my engine builders test mule...... My old school SBC stuff is just fine. Both cars are EFI so sticking an LS in there is no issue.

Most of the guys that run aluminum blocks with big power have them resleeved with Darton or something similar. From what I can tell, you can start with a 4.8L/5.3L block and go with bore of just over 4". If you have longer than stock sleeves installed, it keeps more of the piston skirt in the bore at BDC which can be an issue - can be done on some blocks but not others.
Piston squirters can be added for high temp/boosted applications.
Grab your wallet...

The LS platform is a near the top in my opinion.

Pros

Carburetor conversion intake is the same cost as a standard small block Chevy.

You can make well over 600 HP on a stock bottom end as long as you don't spin them above 6,500.

Bolts up to a standard GM transmission (PG, 350/400) with only a spacer or flexplate.

You can put the entire motor together with only a couple dabs of silicone in key areas.

There is no distributor to worry about and the ignition box is about the same price as standard unit.

You can use a BBC electric water pump with a set of adapters that cost ~$30.

The cam/crank sensors rarely fail and can be found at a local parts store readily.

Coil on plug actually provides a hotter spark due to lower duty cycle.

Cons

You will typically pay more for things like headers, rocker arms and oil pan for a given application.

Tack weld the reluctor ring to the crank, I've seen a bottom end wiped out from the ring coming lose on a Lunati crank. (Factory cranks are better on this.)

Oil pumps/pans are more expensive and a bit harder to install, take care of the o-ring on the oil pickup.

Aluminum blocks are typically junk after even a 0.01-0.02 overbore, stay away from these as you will likely get pinholes or cracks in the cylinder.

Higher RPM combinations tend to aerate the oil due to the oil pump and windage area design.

They take metric bolts and the head bolts are torque to yield unless replaced with aftermarket parts.

Thanks for that info Ryan.

Most of that I have been told by people running these engines.

They are great (the 4.8/5.3) to stick a turbo on and make stupid low-rpm power CHEAP! the small bore provides a lot of head gasket. Keep it below 20psi and they tend to live a long time.

But, for those of us that want to Bracket Race the thing week after week, putting 500+ passes on before a freshen, not sure if the aluminum block, or this type of engine without a lot of thought and attention to areas like the oil system above 6500, is really worth it.

How many people even Bracket Race with EFI? I have been since 1990, but I am still the oddball out there. Carbs gotta be 1000:1 if not more in Pro/Super Pro type cars. Street ET, well, there should be a LOT of EFI there, it is a "Street Class" afterall....