building a 466 bbf for mud racing what do you think of this...

bigunitmudracing Wed 13 Jul 2011 - 0:10

I am building a street stock race engine and have to pull vacuum..

.030 over probe pistons, c9 rods with arp bolts, c9 crank ground .010/.010, balanced lower end.
comp cam.. extream 4x4
real nice truck heads, fresh valve job and new valve springs.
preformer intake and a 750 edlebrock carb...

any tips for more power?

rmcomprandy Wed 13 Jul 2011 - 0:31

It all depends upon the rules you need to follow and whether or not you want to win or keep it a dual-purpose truck and simply compete ... use as much compression ratio as you are able to use for starters.

schmitty Wed 13 Jul 2011 - 0:36

X2 on what Randy said. Compression is your friend when needing vacuum. Cool

bigunitmudracing Wed 13 Jul 2011 - 10:55

cam
262h
gross valve lift . Intake .514/ exh..524
dusration @50. 218/226

e7 heads off of a truck , no porting or polishing allowed.. just a full valve job and comp 926-16 valve springs..

probe flat top pistons

dfree383 Wed 13 Jul 2011 - 10:57

get some early small chamber heads and get some one to grind you a custom shaft for the application. You need more compression.......

Talk with someone like randy about some heads, theirs more to be had with in the rules only stating no porting and polishing, if your looking to be compeditive.

lghting94 Wed 13 Jul 2011 - 15:12

Can you post your actual rules so everyone can see where there may be room for interpitation. This will allow better answers also.

bigunitmudracing Wed 13 Jul 2011 - 16:57

Headers allowed with max 1 7/8 size tubes.

4. Mufflers must be bell shape and glass packs allowed, no cutting of mufflers.

5. Any external modification allowed: any single carbureted intake, carburetor, and ignition.

6. Factory fuel injection allowed.

7. Any factory production (truck, van or suv) heads are allowed. No after market performance heads.

8. Engine block and lower end must be stock for year, make, and model. Can check by 8th V.I.N. number.

9. No high performance engines.

10. No internal engine mods, aka timing gears, if found will have to bump up a class.

11. Engine may have maximum overbore of .060. Piston and piston height to be stock configuration, Deck height to piston must remain stock.

12. Engine must remain in stock position.

13. Engine must pull 15" of vacuum at 900 RPM. Can and will be checked at random. If fail bump a class.

14. No porting, polishing, or grinding of any kind on heads. Maximum valve diameter must be stock according to casting numbers on stock heads.

15. Pistons to be flat top or dish according to year, model, and make. No domed pistons.

16. Any radiator may be used in stock position only. No cutting of hoods.

17. Converters and clutches must be stock for vehicle.

18. Gas only, no nitrous or alcohol.

dfree383 Wed 13 Jul 2011 - 17:06

Get Early heads (C8,C9 or Dove), Angle Mill (Get the chamber as small as reasonably possible) , Bowl Hog and Proper Valve job (Not just a generic 3 angle), SS Valve, "0" deck the block.

With a stock type FT pistion you should be able to get in the 12:1 range (This will help you vac readings and make power)

Get a cam ground for the application (This is very, very Important)

Use a Performer RPM and a 950 hp carb.

Get Headers and have the "Stock" convertor Restalled........ Talk with a convertor company and who ever you have grind the cam.

Ignition will also be very important, it can make or break a Vac rule motor.

IcallhimGeorge Wed 13 Jul 2011 - 18:32

Dont take offense but who wrote these rules? Sounds like a backwoods "I really dont know whats going on" tech sheet. How is the tech guy going know if you have ported heads, oversize valves, .080 overbore etc unless you agree for your engine to be torn down?

Ive got a local track with similar rules and its laughable at best. The "tech guy" knows about as much about racing as I do about flying airplanes.

#9 makes me laugh. At what point does an engine become a high performance engine?

rmcomprandy Wed 13 Jul 2011 - 20:33

bigunitmudracing wrote: Headers allowed with max 1 7/8 size tubes.

4. Mufflers must be bell shape and glass packs allowed, no cutting of mufflers.

5. Any external modification allowed: any single carbureted intake, carburetor, and ignition.

6. Factory fuel injection allowed.

7. Any factory production (truck, van or suv) heads are allowed. No after market performance heads.

8. Engine block and lower end must be stock for year, make, and model. Can check by 8th V.I.N. number.

9. No high performance engines.

10. No internal engine mods, aka timing gears, if found will have to bump up a class.

11. Engine may have maximum overbore of .060. Piston and piston height to be stock configuration, Deck height to piston must remain stock.

12. Engine must remain in stock position.

13. Engine must pull 15" of vacuum at 900 RPM. Can and will be checked at random. If fail bump a class.

14. No porting, polishing, or grinding of any kind on heads. Maximum valve diameter must be stock according to casting numbers on stock heads.

15. Pistons to be flat top or dish according to year, model, and make. No domed pistons.

16. Any radiator may be used in stock position only. No cutting of hoods.

17. Converters and clutches must be stock for vehicle.

18. Gas only, no nitrous or alcohol.

What year is your vehicle...?
You're already "cheatin" so you may as well do it right.
You say you have "flat top" pistons; only in a 429...?
By those rules you CAN'T use anything except a STOCK camshaft with STOCK timing gears.

As has been eluded to ... what is their enforcement like and what do they do to police this stuff...?

Just about any racing type organization wil say nothing about anybody cheating as long as they finish at the bottom of the heap. Start winning all the time and you better be legal.

IcallhimGeorge Wed 13 Jul 2011 - 20:47

around here if you are accused of cheating - having an engine that doesnt meet spec, yet pulls required vacuum
the person accusing you must put up $250. The accused can either take the $250 and tear his engine down or forfeit winnings in his class and have the $250 donated to the track. If the accused was not cheating (everything is within class rules) he keeps the winnings and the $250.

Winnings on most sanctioned tracks are $1000/1st $500/2nd and $300/3rd unless its something special or theres an usually high number of trucks running that class.

Regardless its never been enough for me to pull the heads and oil pan off a muddy ass motor just to prove a $250+winnings point.

The non-sanctioned tracks will have similar rules to what you posted and every non-sanctioned track will have different rules. The "tech guy" will usually be a pool boy or short order cook monday-friday and has absolutely no clue what hes looking at let alone know how to work a compression tester or vacuum gauge.

Id keep the externals looking pretty much stock and let the internals eat.

bigunitmudracing Thu 14 Jul 2011 - 0:39

lol... well this is the best part!!!!
i took 3rd in Baraga and payout pas $13 and i paid $25 to race that class
in Champion i took 2nd and the payout was $16 again i paid $25 to enter the class
and in Sanborn i took 2nd also and the payout was $87 and i paid $20 to enter that class
This is all races from this season...

and that was with a dish piston motor that is no longer with us...LOL..

I belive i am still racing and i was the tech guy for a while, we have a bore scope but i am the only tech who has ever used it..
I am no longer a tech guy.

Its racing so push the limits a little... I'll never let anyone tear me donw for what the payouts are....

dfree383 Thu 14 Jul 2011 - 8:20

soooo...... 472", Flat top, Angle mill and Bowl hog a set of early heads, get a custom cam groung to make the Vac, Performer RPM, 950 HP and headers....... Then lift to just squeak by for the win or second a few times..... you should be good for a few seasons untill the figure it out....if they ever do. Laughing

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building a 466 bbf for mud racing what do you think of this...

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Re: building a 466 bbf for mud racing what do you think of this...

Re: building a 466 bbf for mud racing what do you think of this...

Re: building a 466 bbf for mud racing what do you think of this...

Re: building a 466 bbf for mud racing what do you think of this...

Re: building a 466 bbf for mud racing what do you think of this...

Re: building a 466 bbf for mud racing what do you think of this...