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Author Topic:   Hobby stock engine build ideas?
posted June 29, 2003 09:50 PM
I need to build a engine for my IMCA hobby stock. we must use flattop pistons and maximum 360 cid. I would like to get some ideas on a good rotating assembly for around $1000. thanks

posted June 30, 2003 09:51 AM
starting from scratch:
scat crank ~$200-$250, scat 4130 i beam rods ~$200, speed pro hyper pistons ~$100-$140, clevite brgs ~$40, sealed power rings ~$40, balance job $150 that gets you good bottom end minus block for $750-820. Throw in a cam, cloyes roller chain, and a good block and you have what most of the top hobby cars at our track are running

posted June 30, 2003 04:56 PM
thanks thats what I was thinking.

posted June 30, 2003 09:59 PM
Originally posted by ohiodirt:
don't re-use stock rod bolts. i know, i know, you guys told me not to and i should have listened. now there is a huge hole in my oil pan and the rod is somewhere buried in the track. buy good rod bolts. just some advice.

Does it look anything like ours? It wasn't a stock rod bolt either.


[This message has been edited by dode (edited July 01, 2003).]

[This message has been edited by dode (edited July 01, 2003).]

posted July 01, 2003 07:44 PM
starting from scratch:
scat crank ~$200-$250, scat 4130 i beam rods ~$200, speed pro hyper pistons ~$100-$140, clevite brgs ~$40, sealed power rings ~$40, balance job $150 that gets you good bottom end minus block for $750-820. Throw in a cam, cloyes roller chain, and a good block and you have what most of the top hobby cars at our track are running

Add gaskets, boring, honing, what about cylinder head work? Will the heads accept the cam's lift, valve springs? Your over $1,000 and have a chinese crank and rods with passenger car load rated bearings. Not saying anything bad about that stuff,just not where I'd stick my money.


How do you know a rod bolt broke if you haven't even pulled the engine apart yet?

posted July 02, 2003 09:19 AM

If you read his post it says he was interested in a rotating assembly for around 1000. doesnt say anything about heads and machine work. Of course the total cost would be higher after getting a block and heads prepped and assembling it. As far as Chinese stuff goes remember this is a hobby stock engine, so basically a little more than a stock rebuild. There is no need to spend gobs of money on steel cranks and heavy duty rods or bearings. It will hold up fine, we have been running nearly the same combo in a 13:1 mod and turning 7200 with it and havent had any problems.

posted July 02, 2003 10:59 PM
rktpwrd I think they got a pretty good combo going for the money lets here where and how you would go different....Towman

posted July 03, 2003 12:19 AM
(A) Steel V-8 block, heads and intake only.
(B) Maximum 361 cubic inches (GM): 363 cubic inches (Ford): 370 cubic inches (Chrysler).
(C) Maximum compression ratio is 9.0 to 1. Flat top pistons only, no gas ported pistons.
(D) Cylinder heads must be unaltered approved OEM and minimum 76 cc combustion chamber. No Vortec heads, GM approved steel head numbers are - 267, 336, 339, 388, 393, 441, 445, 454, 487, 493, 545, 598, 624, 642, 862, 881, 882, 920, 991, 993, 997; Ford - no after market or W2 heads, 360 cubic inch heads only. No porting, polishing or alterations of any kind to heads, disqualification and $250 fine if illegal.
(E) Engine must appear strictly stock. GM with GM, Ford with Ford, Chrysler with Chrysler. No 400 or larger cubic inch parts allowed. Stroke must match block. Harmonic balancer may not be altered.
(F) Must have unaltered approved OEM cast iron two barrel intake. No porting, polishing or alterations of any kind to intake, disqualification and $250 fine if illegal.
(G) No full roller or roller tip rocker arms, roller lifters, or stud girdles. Studs may be pinned or use non-shouldered ***** -in type.
(H) Minimum two-core approved steel or aluminum radiator. No aluminum water **mps on G.M. cars. Steel or aluminum V-belt **lleys only. Overflow tubes must be directed to ground, between frame rails. Accumulators and Accusumps must be mounted under hood. Stock steel accessory brackets only.
(1) Compression ratio using Whistler and cubic inches using **mp.
(2) Visual inspection of part numbers, casting numbers and flat top pistons.
(A) $325 (U.S.) cash claim on engine, flywheel and balancing plates - $25 of this goes or wrecker **lling engine.
(B) Claim does not include - 1. Flywheel, 2. Clutch, 3. Pressure plate, 4. Bellhousing, 5. Valve cover breathers, 6. Carburetor, 7. Starter, 8. Motor mounts, 9. Sending units and switches for oil pressure and water temperature, 10. Fan and **lleys, 11. Clutch ball, 12. Clutch arm, 13. Throw-out bearing, 14. Dip stick, 15. Water **mp, 16. Fuel **mp, rod and plate, 17. Distributor, 18. Plug wires, 19. Water outlet and restrictor. EXHAUST MANIFOLD GOES WITH ENGINE.
NOTE: During engine claim, exhaust manifold must be **lled to inspect heads and one spark plug must be removed to check for flat top pistons prior to transfer of engine to claiming driver. If, at this time, heads or pistons are found illegal, claimed driver is disqualified and suspended from all I.M.C.A. sanctioned events until such time as a $250 fine is paid, for first offense. Claimer has option to accept or decline engine. If claimer declines, claim is not charged against him/her. Second offense penalties will be same as engine refusal, loss of all I.M.C.A. points, 30-day suspension and $1,000 fine.

If your just starting out, go cheap. A stone stock good running engine, can actually compete, in the hobby class if everyone is playing by the rules. Dial the car in and get used to driving. It's cheaper to make mistakes and hurt a engine that you don't have any $$ into.

If your seriously looking to spend some money in a hobby engine. What dirtbuster stated is a pretty good deal, especially for new parts.

I'd probably just take a good running engine, hone it, polish the crank, open up the rod side clearances if needed.Set the quench to .035-.040 alot of times you can just use a fel-pro F1094 .015 thick steel shim head gasket,stock pistons seem to be .020 -.025 down in the hole, no need to deck the block then. Small solid cam, toss all the valve rotator retainers in the garbage, and add new valve retainers, locks, springs and seals. Back cut the stock valves. Cloyes chain also sounds good, degree camin with degree bushings if you need to. Hog out the exhaust manifolds, since I don't see anything in the rules about that. The aforementioned clevite bearings are also good. Speed pro, perfect circle file fit or cheaper sealed power rings seem to work great.

I'm a cheap *******, it will run with the rest of them. And if it gets claimed, you'll get your money back that you have invested in it with 0 to hardly any loss.

Just my opinion. Engine is only a part of the whole deal. Good luck!

[This message has been edited by rktpwrd (edited July 03, 2003).]

[This message has been edited by jammin (edited July 03, 2003).]

rico 08
posted July 03, 2003 08:34 AM
Running cheap parts can be fun,i ran a core engine once with only a small solid lift cam,new oil **mp,timing chain,the rest was just the way chevrolet built it,turned it 6200 'till the sludge in the motor(cleaned out all i could)got loosened up by racing and clogged the pickup to the oil **mp,i was running with a speedway 377 at the time.$100 engine lasted three races but could have been alot longer if i hot tanked it.

DMA Racing
posted July 03, 2003 08:56 PM
guy i know went to advance auto parts got a 350 long block,around 650.00 **t a 425 lift cam in it and raced two years with it.won a lot of races.

posted July 08, 2003 01:17 AM
remember the word HOBBY.
Keep it cheap, and it will be a hobby, not a job. Sooooo many racers make this distinct mistake and no longer enjoy our wonderful sport. Also remember how narrow of a tire we run. A nice stock bottom end will take what a 2barrel can throw at em.
For example. Stock chevy X rods are designed to handle 8500 rpm off of the shelf. try 9 grand and poof, but up til then, you're good. Keep your hobby stock a HOBBY, it'll be alot more fun, just as fast because you'll just learn how to drive a tamer engine. My big dog in the car now is actually little fun to drive, i liked the litte guy better, god knows i did better with it.....

posted July 13, 2003 07:58 AM
Great reply, skinney!!! It's suppose to be a hobby, most of the guys in west central Ohio have lost sight of that! By spending more and more they move the class up to another level for no more payout! Promoters win, drivers loose and it's our fault! Just my 2 cents...loojack

"loojackracing, a not for profit organization"

posted July 15, 2003 12:06 AM
hey loo jack welcome to how things are up in my neck of the woods a.k.a canada.... we had a class called the enduro class but well we had guy buyin use semi pro motors and kickin *** and well next thing you know the track gets ride of that class and well we are **** outta luck.. and well the class we get is like semi pro but closer to late model...

posted July 15, 2003 12:08 PM
hey loojack where do you race at? I go to Midway Speedway in Crooksville,Oh also ohiodirt where do you race.

[This message has been edited by mikehaze (edited July 15, 2003).]

posted July 16, 2003 08:09 PM
Hey Fomocosho,

We run a full balanced assembly from Eagle
had 46 nites on the set-up last yr and
never tore it down, re-ring and bearing this yr and have about 15 nites and 3 features on it. if it were me i would look into these packages. Your engine builder should now how to get a hold of one. He might not llike it because he cant do the rods and grind the crank but you cant beat the price..

Sir Rods
KB pistons
Eagle crank
clevite bearings
federul mogul rings

Price was around 6-700 total
through in machine work and your whole bottom end is $1000

posted July 16, 2003 09:07 PM
Thanks for all of the replies. Right now
I think Im going to go with a JR Motorsports classic rotating assembly. Hey Squid where did you get your Eagle rotating assembly? Has anyone else tried a kit from JR?

posted July 16, 2003 09:44 PM
they are some great guys used to be the top dogs at midwest motorsports but desided to start there own shop with jr motorsports in boone give kelly a call he can hook you up with what you need

posted July 17, 2003 11:39 PM
hey fomo

i run around southern MN and northern IA, but these kits are available straight from eagle. let me know were your from and i can really get a supplier for you. the guys that do our machine work i went to school with and help us out alot. just give me a holler

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