Building a cheap SBC...help me plan

Hyper piston seem to have problems with anything over 36 deg advance. There been many reports of the whole top cracking off in the 1st ring land. Last year or so there was a guy on the WAR board who was just starting out and got a "Rebuilt" distributor from a nat chain store Next week he roasted the motor. He found a shop with an old SUN distributor machine turned out the max deg setting was 42deg.

Many people like to just weld the advance, but then they complain of burning up starter and hard starts...WTF. Have it set up with light advance springs so full timing come in at 2500rpm and 32-34 max spot weld and file the slots if needed. Some shops use little clips in the slots but spot weld it better. Remember good crank and all the other goodies do nothing if you can't acuritly fire the mixture.

Oh did they put in no MARINE intakes? There are a few stock chevy high raise 2brl intakes for boats but most tracks ban them. If you are going to run a 2brl give Dayton Umholtz a phone call. I know he was booked soild a few months ago but he builds some nice carbs and he'll tell you upfront if what you have is going to work or not. http://www.kineticperformance.net/ I've never used him myself but i've tuned cars with his stuff and he does some mighty fine work. Talked with him a few time on the phone too. He's 1 of two people i'd trust with carbs the other ( Eral Parker Jr.) is no longer working on carbs.

44

I've never seen a street stock type motor break pistons at 40 degrees. Sounds like another problem.

If you set up the dist. at 40 (or whatever), install a toggle switch on the ignition so that once it's turning over, hit the ignition, and it'll fire right up. You can also run the weights and springs, and set your total with a good timing light so it's all in around 3000 RPM

No significant gain .060" compared to .030", but it doesn't cost anymore, so you might as well do it while you'r in there.

Don't think there's any gain with 2.02 valves over the 1.94 at those RPM's, but I could be wrong. For a beginner/midpack car, I don't think it matters.

If you need help with the cam, let me know. Cams are my thing.

We ran a long 3/8 with good bank, but had to run auto trans. We ran 1st gear.

Your local spring/parts supplier will probably tell you what everybody is running, but I'll be it's 1000-1200 lbs front springs and 200 lbs rear +/-

44Dwarf wrote: ...Have it set up with light advance springs... ...MARINE intakes... ...Dayton Umholtz... 44

Thanks for that info!

I don't see in the rules where marine intakes are ruled out. If I come across a good deal on one, it would be worth giving a try (though here in the midwest, I don't figure I'll be finding one in the junkyard, necessarily).

They'd probably come up with a "Clem Rule" if I did that and did well ;).

I'll keep that carburetor builder in mind. I figure I'll put something together myself or get a used one for cost...but eventually, I'll probably want "good stuff."

Clem

zomby woof wrote: ... If you set up the dist. at 40 (or whatever), install a toggle switch on the ignition so that once it's turning over, hit the ignition, and it'll fire right up. You can also run the weights and springs, and set your total with a good timing light so it's all in around 3000 RPM Don't think there's any gain with 2.02 valves over the 1.94 at those RPM's, but I could be wrong. For a beginner/midpack car, I don't think it matters. If you need help with the cam, let me know. Cams are my thing. We ran a long 3/8 with good bank, but had to run auto trans. We ran 1st gear. Your local spring/parts supplier will probably tell you what everybody is running, but I'll be it's 1000-1200 lbs front springs and 200 lbs rear +/-

Wow...thanks again!

I'll keep all the timing info in mind...I hadn't even thought about turning on the ignition once the engine was cranking (duh!).

Nice to be grounded in reality. .08 in valve diameter isn't going to be a discernable difference to a beginner and/or a miser.

I'll definitely hit you up for cam advice when this starts to happen (warning...that is likely to be a year or 3 from now ;)).

I see...running in other than 1:1 on the trans. I hadn't thought too much about that either. I used to run in 2nd a long time ago.

I haven't decided auto or manual yet, but I'll go manual when I can (there's quite a bit of cost involved in bellhousings and throwout bearings and clutch and such).

That's an awesome starting point on springs...thanks!

Clem

Camel hump heads are worthless. If anyone wants to prove me wrong, make me an offer before I throw out the set of them i have.

Clem, if you ever get this thing done, let me know. First, I'd be curious what your dyno numbers would be. Second, by the time you're done the girls might be old enough that I could get away occasionally and help with the car.

hypers are sensitive to ring end gap, 2barrel intake off early 70's bus, has canada cast into the top of it, a set of scat rods are only 200 (beats the heck out of stock rods with good rod bolts) my personal choice for cam would be in the range of .450 to.480 lift with 220 to 236 duration (at .050) gear it to turn about 6200 to 6500 side note my claimer 350 engines used a 400 flex plate, i then neutral balanced the rotating assy with the 350 balancer, the claim rule let you keep the flywheel, i had 2 claimed, and the new owners never could get the "shake" out of them

Travis_K wrote: Camel hump heads are worthless. If anyone wants to prove me wrong, make me an offer before I throw out the set of them i have.

I'll give you 1 penny plus shipping...

Unless shipping costs more than $50...then I'm out ;)

but I'm also quite serious.

Uh...yeah...really.

Clem

stroker wrote: Clem, if you ever get this thing done, let me know. First, I'd be curious what your dyno numbers would be. Second, by the time you're done the girls might be old enough that I could get away occasionally and help with the car.

I will bring a 12 of Schlitz to your place any night I don't have my kids just to hang out...like NOW.

but yeah...there will be no dyno, but there will be lots of fun involved in putting this mess together.

I have a strong lead on a chassis (roller) to build, and a lot of "trading fodder" to get this thing rolling.

What you can do is keep your eyes out for stuff like wheels, 3 speed trannies, 9" ford rears and/or gears, 2bbl carbs, etc.

Seriously, we should get together.

Ok...I'm stoked about racing!

Clem

warpedredneck wrote: hypers are sensitive to ring end gap, 2barrel intake off early 70's bus, has canada cast into the top of it, a set of scat rods are only 200 (beats the heck out of stock rods with good rod bolts) my personal choice for cam would be in the range of .450 to.480 lift with 220 to 236 duration (at .050) gear it to turn about 6200 to 6500 side note my claimer 350 engines used a 400 flex plate, i then neutral balanced the rotating assy with the 350 balancer, the claim rule let you keep the flywheel, i had 2 claimed, and the new owners never could get the "shake" out of them

sneaky.. that's a good way to keep people from wanting to ever claim your motor or to get beat by your own motor after it gets claimed.

So...

Any advice on if I should run a solid or hydralic cam/lifter setup?

Thanks, Clem

Solid will allow you to run a more aggressive lobe, but it's not absolutely needed for the RPM's you'll be running. Use what you can get cheap in the .480"-.500" lift range, and 230-240 duration @ .050". The lesser duration with hyd / the more with solid.

If you want to send me boxes to put them in, $5 plus shipping and they are yours. lol

One of the tracks we used to run had a cast iron exhaust rule. The hot setup for a SBC was a set of marine exhaust manifolds. Chet Herbert makes an excellent hydraulic cam for not much money, that also worked very well. Running an automatic will suck more power from you than a stick, but if required by the rules, decide if you're going to run a powerglide or a turbo 350. If you go with a powerglide, use an aluminum one from a six cylinder. The gear ratio for first will give you a slight advantage over someone with the same rear gear set. Powerglides are getting harder to find though, the drag guys swallow up all they can find. If you have to run stock springs(and no load bolts) find some station wagon or truck springs that fit and cut them down to stiffen the RF. Usually stock rears will work adequately in the back on dirt. Scrounge some decent heavy duty shocks(again ,pick-ups). A well handling car is much more important than a higher powered one. Make good friends with the local junkyard- they'll be priceless. Buy a tire groover and do your own. All the power in the world won't be worth a hill of beans if you can't get any bite. You're putting the horse before the cart, though. Learn some basic chassis setup and driving, then you can add power. Just my 2 cents from many years of expensive lessons.

minimac wrote: All the power in the world won't be worth a hill of beans if you can't get any bite. You're putting the horse before the cart, though. Learn some basic chassis setup and driving, then you can add power. Just my 2 cents from many years of expensive lessons.

I think you're surmising that I'm placing lots of weight on having a good engine before worrying about handling. I'm very sorry if I led you to believe that...because it's the furthest thing from the truth. I know first hand that handling is very important (I also know that dirt track racing can be a series of short drag races).

I don't think making sure I have an engine that will stay together is bad. Truthfully, I may start with a junkyard stocker...but soon after I want something ROCK SOLID and with enough power to have fun.

I'm pretty confident I'll pick up the knack of setting up a dirt circle car pretty quick. I'm already good at road race cars...so it'll come quickly to me.

But anyway...I can't groove tires. I pretty much have to run street tires. but that's OK because they'll last forever if I stay out of other people's fenders.

Well...I picked up my first of a couple of $50 engine cores this past weekend.

it's a one piece Rear Main Seal (RMS) bock with heads off of something older. I haven't done much except retrieve it and set it on a stand at this piont.

PO said it smoked but ran fine...sometimes fouled a plug.

I figure it's a good candidate to tear down and rebuild without going full out doing a full out "blue print" on it. Bore/hone, check the clearances on the bearings, bolt it back together with new pistons/rings/bearings/gaskets/cam/lifters/springs, and use it.

It'll be a while before I get around to it...but I'm excited to have it.

The other $50 core engine (GM Goodwrench Mexico-made replacement engine that has been sitting outside for a long time) should come home in the next week.

Between the two, I'm guessing I can come up with at least one good engine.

Clem

a bit off-topic but still reasonably relevant, is there anything performance-wise that can be done to a 305 during the course of a block-up rebuild? not necessarily aftermarket stuff, just parts from other SBCs that might be compatible with a 305 block/heads? this is in a '83 Caprice Classic that currently has a pretty bad piston knock and is in desperate need of a rebuild for the customer (tech center project car, the cat who owns it wants to swap in a 350 but we have to use the 305 if we can save it. not to say we can't spruce it up a bit in the process though...)

The prevailing wisdom on 305s is that if it has to come out of the car...and you're thinking about performance, you are money ahead to just put a 350 back in its place.

That is...all the same stuff that works on 305s works better on 350s and the 350 parts are cheaper.

Generally folks cite the smaller bore as the culprit for the 305's inability to respond as well to the same modifications. The smaller bore "shrouds the valves" such that airflow is limited...again, according to prevailing wisdom. I'm not an expert on this, but it passes the logic test.

All that said...pretty much anything you could do to a 350 you can do to a 305. Cam, headers, port/polish heads, etc. It can't hurt, really, in my opinion...it just won't help as much as it would on a 350.

I wish the 305 was a more accepted perfomance engine (because there are megatons of them out there)...but the fact that it is universally rejected probably stems from valid reasoning.

Clem

I literally could not get a 12 pack of Hamm's or Schlitz beer for a rebuildable core 305 engine I had. I gave it away to a vo-tech type teacher for use in the classroom, though.

hm, I'm almost hoping that it would be money ahead to find a junkyard 350SBC or even a junkyard LS1/slushbox combo out of a wrecked Camaro, since the guy wants to drop in a 350 anyway

Instead of Camaro/Firebird LS1s, it will probably be a lot cheaper to look at LSx-based truck engines. A stock 5.3L out of a late model pickup will be so far ahead of any 305 GM ever made he'll be more than happy with the performance. The only issue, typically, is the trucks have taller intake manifolds, but that's fixable with stock Camaro parts. Wikipedia can help you sort out what's engines went in what.

Sorry, I forgot to include the link originally:

Wikipedia LSx Page

Bob

I have ran a lot of sbc the best one I ever had was a 350 bored over 30 with flat tops a rowdy cam... MSD and double hump heads ported and polished.

I've always desperately wanted a destroker with an insanely high stall that made people's ears bleed and other racers knees weak.

I always spend too much on parts... Feel free to PM me for my phone number if you want me to empty your wallet.

Lot of good advice here already so I'll just add my 2 cents. For the carbs, If you run an Motorcraft 2150, Here is the list of CFM's. It's helpful when you are looking for one from the yard. They use to have a no holley rule in IMCA

The number can be found on the side of the float bowl, right behind the accelerator pump rod, inside of a circle.

Number = CFM .98 = 190 1.01 = 240 1.02 = 245 1.08 = 287 1.14 = 300 1.21 = 351 1.23 = 356 1.33 = 424

One thing that is often overlooked is the gearing and revs. I know when I started working on my first Hobby stock, the gearing was all wrong and the owner said he never even looked into it. Once I did the math and got the right gears in the car he picked up .5 seconds a lap.

three year old zombie thread...

did this ever get on the track, and if so, how did it go?

I have not put it together or had it on the track. I have been slowly gathering parts. I have a used-up roller chassis/body, a transmission, a steel bellhousing, and a few other little things.

Other projects have kept me from spending time or money on this one...but it may come together some day. Or...it may get traded off in favor of something else...who knows.

I do have the trailer almost ready to go though