Carbureted LSX forum - Carb'd LS build for dirt track (lots of pics)

Thought I'd share some pics and story of my engine build. Short story: Built last year as a 402, this engine was ran for a few races in a USMTS style modified and one race in my dirt late model. Had some oil control issues that resulted in needing a fresh block (got the mains a little hot). Since the motor was apart I decided to upgrade a few things like a bigger bore, some cyl. head work, better intake, better carb, etc. So here it is, all 408ci of it, 13.5:1 compression, solid roller, distributor conversion. I have to admit I'm pretty stoked about it and can't wait to get it in the car. Bring on the pics!

Cutting the deck a little:
http://i186.photobucket.com/albums/x27/stephens56/444-1.jpg

Crank and cam and timing components in:
http://i186.photobucket.com/albums/x27/stephens56/459-1.jpg

Full custom RaceTec pistons with dome to match my heads combustion chamber:
http://i186.photobucket.com/albums/x27/stephens56/462-1.jpg

Rod assemblies ready to go:
http://i186.photobucket.com/albums/x27/stephens56/463-1.jpg

All in:
http://i186.photobucket.com/albums/x27/stephens56/465-1.jpg

Oh yeah! :
http://i186.photobucket.com/albums/x27/stephens56/466-1.jpg

Bottom end all buttoned up:
http://i186.photobucket.com/albums/x27/stephens56/468-1.jpg

The start of a custom 50* intake valve job:
http://i186.photobucket.com/albums/x27/stephens56/375-1.jpg

Another shot of the intake cut:
http://i186.photobucket.com/albums/x27/stephens56/379-1.jpg

Heads ready to go together:
http://i186.photobucket.com/albums/x27/stephens56/432-1.jpg

Measuring valve spring height:
http://i186.photobucket.com/albums/x27/stephens56/428-1.jpg

Heads assembled and ready to install:
http://i186.photobucket.com/albums/x27/stephens56/437-1.jpg

The icing on top:
http://i186.photobucket.com/albums/x27/stephens56/445-1.jpg

Heads and lifter valley cover on:
http://i186.photobucket.com/albums/x27/stephens56/469-1.jpg

A quick shot of my stainless cross-over set up:
http://i186.photobucket.com/albums/x27/stephens56/482-1.jpg

All dressed out and ready to fight:
http://i186.photobucket.com/albums/x27/stephens56/478-1.jpg

On the run stand with the headers that fit my race car:
http://i186.photobucket.com/albums/x27/stephens56/490-1.jpg

For those of you not familiar with circle track stuff this is a shot of the magnesium bellhousing with its rear mounted starter. The flywheel is very small (6 1/4" in diameter) and only weighs a couple of pounds, makes for wicked throttle response. The flywheel also has a cogged belt drive on it to run a belt driven power steering/fuel pump that mounts on the bracket on the upper left of the bell.
http://i186.photobucket.com/albums/x27/stephens56/485-1.jpg

So that's it, I hate to take a WAG at a horsepower number, but it should be enough for a 2200lb car.

Enjoy the pics!

Nice pics, in for the rest of the build. What kind of car is this going in? What trans?

2008 Rayburn with a BERT 2-speed trans. This pic was before going to a special "topless" race.

http://i186.photobucket.com/albums/x27/stephens56/2011%20Late%20Model/042.jpg

Awesome!

Thanks for the pics. Better than watching powerblock.

Is coil on plug (with MSD box) not allowed?

looks good!

Is coil on plug (with MSD box) not allowed?

Engine rules for this class of car are pretty loose but typically say "must be distributor fired" or "only one ignition coil allowed". Most common engine combination is a 410-430ci (a lot are spread bore spacing blocks) with any head allowed as long as it's 2 valve per cylinder and one spark plug per cylinder, 750-850hp is what the good ones are making and cost upwards of $40K.

So how much HP you think? You think you will be competetive power wise?

I really hate to guess, but it has enough cam, compression and cylinder head to make around 650 at the crank ( I think). A wheel hp number would be hard to guess because these cars' drivelines are so different from a street car. Will it be enough for the series I'm going to run with? On a small track, maybe. On a bigger half-mile or a fast 3/8 mile track, I probably don't stand a chance at the top 5.

Im building one for a ump modified very similar to your combo, are you on gas or alcohol? I am also curious about your oiling problems, I currently have a kevko circle track pan, afco deck mount cooler, cvr remote filter boss with a melling pump.

Im building one for a ump modified very similar to your combo, are you on gas or alcohol? I am also curious about your oiling problems, I currently have a kevko circle track pan, afco deck mount cooler, cvr remote filter boss with a melling pump.


I believe it was a combination of things: main clearances were too tight, a Melling 10296 pump (ran the pan dry), thin rings, and a rear main seal leak that didn't leak until high RPMs. So the new combination has .0035 clearance at the mains, a Melling 10295 pump, a custom 1/16, 1/16, 3/16 ring set, and I made an alignment sleeve for the rear cover so the seal has a perfect fit. If I had to do it again I'd run oil restricted pushrods too, but I was already invested in a nice set of Mantons this time. I also have the Kevko pan but with a FSR oil cooler I bought from Mullins, it was designed for a wet sump applicaton. If you run a stock block you shouldn't have any oil drain back issues, but if you get a LSX block you'll have to modify the valley area somehow to add some return holes because the valley will hold a LOT of oil. I'm on gas with this engine. I was on a half-mile turning 7500, that's why I think it ran the pan dry with the high volume pump. I've since re-routed the oil filter adapter and the cooler lines, made them a little longer to add some capacity to the system. It's got 9 quarts total in it now.

btt.....

Any plans to put it on an engine dyno? I think it should be well over 700 for sure if the heads are done right, and the cam is right.......

Any plans to put it on an engine dyno? I think it should be well over 700 for sure if the heads are done right, and the cam is right.......


No plans at all for it, I have it listed for sale here and on several sites, the car too. I want to get something I can race more often and closer to home. I'll probably go back to a stock car class, there's some races around here I've always wanted to run in.

Where do you run at? Ive got a grt and im wanting to do a ls motor really bad but my local track doesn't allow them yet.

Where do you run at? Ive got a grt and im wanting to do a ls motor really bad but my local track doesn't allow them yet.

I'm in eastern Oklahoma, not too many places to run a LM around here. I've thought about getting a modified, but they cost just as much to run as the LM and the engine rules are tailored to the Brodix spec head engines. Why won't your track allow the 'LS'?

The track promoter doesn't accept change... Theyre are probly over 100 sport mods around the area (central nebraska) but he won't get the class at our track yet. I'm thinking about getting a ls for a few special shows that come through though. How do you like running with one? Is there alot of guys running them around that area?

No sportmods local here either, even though one of the best builders in the country (Big Chief chassis) lives just up the road from here. I like the power of the 'LS', I was able to run down the front straight with 2-time IMCA Natl. Champ Justin Wells at the start of a heat race, but he daylighted me through turn 1 & 2. I got some chassis work to do.......

Did you build it or who did?

I think it is BS the rednecks will not allow the LS with stock heads and a MSD ignition. It is cheaper than going SBC, last longer and the SB Chevy is getting harder to find in decent shape. Not to mention they won't hold rpm without arp bolts and supporting mods.

Guess they will have no choice eventually. 5.3 are everywhere and highly capable. Not to mention the 4.8 will spin 7800 with no problem with a cam and springs.

Just haters.

Did you build it or who did?

Yep, I built it after-hours in the shop.

how much you asking for the engine without distributor drive setup?
Beaudacious

how much you asking for the engine without distributor drive setup?
Beaudacious


It kinda has to have it, there's no reluctor wheel on the crank and all the sensor holes are plugged.

Id put a full MSD crank trigger setup with belt driven distributor on. So how much?
Just like my buddy's car
Beaudacious

I'm in the process of putting an LS motor together for a UMP modified. I know I have to run a distributor but I'm not sure which way to go. The belt driven? Or buy the front cover and run the ford distributor? Neither way is cheap. Which is better?

Pretty gnarly looking, dirt racing is fun bc there ain't no lifting of the gas lol

I'm in the process of putting an LS motor together for a UMP modified. I know I have to run a distributor but I'm not sure which way to go. The belt driven? Or buy the front cover and run the ford distributor? Neither way is cheap. Which is better?
I would go belt drive dist ,way better setup

Why is it way better ? Also whats it cost ? Whats needed ?

IWhy is it way better ? Also whats it cost ? Whats needed ?

I've seen a couple instances where the Spud on the cam came free and did some damage in the front dist app . Plus the belt drive setup works well in high rpm apps and under lots of up and down abuse.

Thats the steam line I'm getting ready to do....just need to pick up some 1/4" tubing.

you should port match the intake to heads. im sure that is worth a little bit. i saw someone who did a port match for his vic jr to his heads and it was RETARDED how off it was


super bad ass btw

13:1 compression on a ls, wow. I bet you want have any problem keeping up with bigger SBC engines.

Awsome to see an LS in modified. Hope it takes off in dirt track. What kind of valve train are you running?

Nice work on the steam pipes. Curious... I read that it's best to run it to the top of the cold side of the radiator so all the steam goes somewhere. Running it to the top of the water pump can allow any steam to collect in the pipe... any experience with this?

I ask because I'm about to put a carb'd LSX in my father's Panoz and am having a new dual pass radiator built with a provision for the steam pipe vs. just putting it to the water pump as others have.

Nice work on the steam pipes. Curious... I read that it's best to run it to the top of the cold side of the radiator so all the steam goes somewhere. Running it to the top of the water pump can allow any steam to collect in the pipe... any experience with this?

I ask because I'm about to put a carb'd LSX in my father's Panoz and am having a new dual pass radiator built with a provision for the steam pipe vs. just putting it to the water pump as others have.

Some say there is no steam, its just a vent line to allow the coolant to fill all the ports so no air is trapped.

As for where the line gets hooked...I think on the suction side of the pump is just fine.

Interesting... always heard them referred to as steam pipes used to get any air created out of the heads from hot spots when racing. If there is no steam then plumbing to the water pump would be fine, but if that were the case then there'd be no reason to have the older style LS1 pipe that uses all four ports.

We also did another LS for a dirt car, a Super Stock is what we call them around here, a 3000lb 2nd-gen Camaro. It was a 427 in a LSX block with a set of worked over iron heads, solid roller valvetrain, Super Victor, distributor cover with a DUI HEI in it. We plugged the vent ports in the corners of the heads, ran no water crossover what-so-ever, had ZERO issues. I think the whole steam thing is over rated.

I think for dirt track racing the distributor conversion cover is better because everything is contained inside, versus a belt drive where everything is exposed to potential rocks and debris from the track. Drag racing would be a different story though.

My complete engine is for sale, BTW.