a SEMI REASONABLE SBC RACE COMBO

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
basics, this engine would NOT be for anything but weekend bracket racing.
ideally youll find a 2400 lb- 2800 lb or lighter weight car.

keep in mind the higher the power to weight ratio and the better the suspension is tuned to allow
the tires to maintain great content traction, the better the car tends to perform,
reducing weight is generally more effective, than minimal increases in power.
(remember to install top quality disc brakes, and the largest tires you can afford in most applications,

consistent to the applications requirements.
remember that race car design is heavily dependent on getting the drive train gearing, matched too the tires, traction, use of the suspension, to maximize the power to weight ratio , and use of brakes and aerodynamics
the basics of a general race engine is to MAXIMIZE air flow rates, compression and displacement,

and DURABILITY, you need to finish a race to win it!
these choices linked below should max the power too weight ratio,
at a semi reasonable cost, using easily available ,
well matched, components.
getting to a 4 lb-to-5 lb per hp should not be all that difficult if proper choices are made,,

and this potentially will provide excellent performance.
heads
Brodix dragon slayer 225cc heads

http://www.jegs.com/i/Brodix/158/1321000/10002/-1

intake
edelbrock single plane

https://www.summitracing.com/parts/edl-2925/overview/


cam with matched solid roller lifters, tall valve covers a rocker girdle and 1.5:1 roller rockers
https://www.summitracing.com/parts/crn-118131

short block
https://www.summitracing.com/parts/drt-03124272

obviously headers and oil pan should match car its installed into,
a windage tray and 8 quart baffled oil pan would be generally required ,
and a 4.11:1 rear gear and a manual transmission, with a 3800 lb rated weber, zoom,
or hays, (good quality )11" clutch and a 36 lb billet steel flywheel.
IF you choose an auto trans youll want a 4000 rpm stall speed converter
youll want a decent ignition, you could go old school, with a vertex magneto ,
or the newer individual coil per cylinder , ignition preferred.
.042 quench,and about 11.3:1 compression, race octane fuel, mandatory.
Id use a properly jetted, 850 cfm holley carb.
Id use 1 3/4" long tube headers, ideally with 38" long primaries, and a 3.5" x 20" collector.
a combo like that should after correctly sorting it uot break into the 9's or at least very low 10s

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on most more modern cars theres no easy to access place to hook a tow strap
so if you intend to trailer and race any car it makes a great deal of sense to customize or bolt or weld on substantial loops or rings too the lower frame where a tow strap can be securely clipped in place to tow or secure the car too a trailer

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extended tow loops can be added too the forward and rear frame rails on the cars corners, by welding or bolting , to allow secure towing or tie downs on a trailer, these come in dozens of sizes and designs
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I've included these video links as all have useful info you'll use on most SBC builds
I'm constantly adding info links and useful info on the existing threads,
most of the time you may not notice the recently added info.
the whole web site is designed to allow you to rapidly find and use,that info.

info you would most likely have a more difficult time finding in any one location otherwise.
I'm trying to allow members to skip over the months/years of dealing with bad info, and wasted time we endured gaining experience,:facepalm::swearing:
most of us older guys went through gaining that experience, and knowledge through trial and error in the past
as in most cases it cost us both a ton of cash and years of dealing with less than ideal results,
so the web site is set up to allow readers who read threads and links to skip the B.S, and wasted cash. :like:
yes I'm well aware reading what looks like endless links sucks,
but you'll rapidly come to see the benefits if you stick to the research
 
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a few more helpful linked videos
keep in mind issues with valve train control, valve train geometry and incorrect clearance issues

are a very common source of problems
and you must supply a constant bath of pressurized oil to cool that valve train and bearings,
adding a 7-8 quart baffled oil pan may not seem all that exciting ,
but using one is going a long way toward reducing that engines chances of self destruction.


 
do your research carefully and talk to your local machinist about you project before you start spending money on parts and machine work!
one factor I really hate about building seriously competitive engines, at a reasonable price is both the required research, and it is that uncontrollable fact, that once you build a really good and cost effective combo, you could safely bet your next 5 pay checks, that inside of a year several of the components you tested and found matched well and you found that worked perfectly in that combo,
are going to be manufacturer discontinued or the price will go up 30%-50% and the part will have been modified in several ways so its no longer compatible, or it no longer fits etc.
I know I built several SBC, BBC, and early 392 hemi engines where I carefully listed, documented and tested combos,
and you go to duplicate it, and its impressive results, a year or two later and 1/3rd of the components and at least one or two of the vendors or manufacturers have recently gone out of business or they say the components are no longer being made.
and of course you spent a good deal of time getting the local machinist in your local machine shop, to do the machine work correctly,, only now you find that the skilled machinist has retired or quite or died, or that machine shop closed!
then you kick yourself because you could have purchased major components you used last year in any reasonable quantity
at 1/2 or 2/3rds the current price , and even at the new higher price the parts offered are not the same quality, or they are on a 4-5 month back order...and if you paid for the part and wait the 4-5 months it really takes 6-7 months to arrive, but your patient, knowing you have a killer combo,
a well proven set of well matched parts.... only to find...after having waited even at the new higher price the parts offered are not the same quality,
or the manufacturer substituted some "improved" non-compatible part to fill your order, or he failed to even read the order correctly, and you listed specific details like a SCAT 4340 steel crank with a 4.5" stroke BBC crank assembly with 4.5" forged pistons and 6.535" connecting rods
and you get a mix of eagle, manely and a selection of some chinese copy's of the part's you ordered (like a cast vs a 4340 forged crank,) and some moron on the service desk phone, who even if you are totally polite and fax him a copy of the order with the details typed on it in large print, pointing out the pistons have the wrong pin or compression height or diameter for the bore size you listed, or the ring's got substituted , and they are not compatible with the pistons shipped.
who won't give a refund, because "its all the same parts you ordered" :swearing: :facepalm:
then of course its was ordered as a BALANCED rotating assembly and its obviously a random selection of mis matched parts your machinist must clearance and balance if its even useable,

best advice always order direct from SCAT, or BRODIX, AFR, CROWER, LUNATI, or at least JEGS AND SUMMIT, as they have a decent track record ,many of the less well known vendors advertising on EBAY, simply have parts dropped shipped, and have little reason to give a crap, as they have your money, and would not know the difference between a 348 crank and a 482 BBC crank if their lives depended on guessing correctly.
 
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