B3 For Dirt Oval Track Racing

[lrcboi]

Heya all,

im new to this forum so a big hi

anyways im done a bit of searching for info and not found so much

Requirements for minisprint (scaled down sprintcar with small car engine)

1300cc or less
more than 4 valves per cylinder you have to be 1200cc
single camshaft only
no fuel injection turbo supercharger or water injection
must be carbied

any modifications

i have a b3 engine at the moment an 8v carby im looking to build up

i plan to run methanol with side draughts with a direct drive from the clutch to quick change rearend

my questions

1. Will the b3 block take an other B series heads? that are sohv 8valve or 12valve NOT 16VALVE

2. I heared that all b3s have forged rods and crankshaft and run 9.7:1 CR is this true?

3. If i can use a different head b6? with methanol and good porting polishing and racing cam how many rpm will the rods, crank and head assembly take? if not very much suggestions are welcome

4. Using methanol and maybe a larger head b5 b6 how much CR is possible?
and where are the best places to make it up ? plane head or deck block ?

5. Dizzy upgrades ? we have the engine positioned north south and the dzzy is pretty much between my legs lol are there any alternatives? or upgrades that are shorter? will probably use MSD ignition box 6AL or something

6. Header size suited to the engine to get the most out of it mid to high range?

7. can somebody give me a ball park figure for hp and tq say with a larger head and agressive porting race cam 12:1 CR custom sied headers side draughts like 32mm maybe 40mm not sure uprated ignition methanol ?

Cheers

[oxbrain]

How close are they inspecting? The b6 block is identical on the outside, but bored out larger. That'll get you a lot more power. Make it sound like a strained out b3, but don't do the expensive work.

1. You might be able to fit a 8v B6 head on the b3 block. I've never tried it to see if everything lines up. The issue would probably be the cooling jacket holes, which might need some grinding or filling.

5. The distributors are all going to be about the same length. I think the efi festiva unit is the most compact.

6. This will depend a lot on what redline you can get, I'd keep it pretty small. At 6000rpm you're only moving about .3 cfm.

7. I don't think anyone has built a very extreme b3 before, so you're breaking new ground. It's just so easy to run a b6 as a cheater motor instead.

[SimonTuffGuy]

I know of a member on the board that does oval dirt racing... He's installed a B6 and plays it off as a stock engine...

[oxbrain]

Everyone I've spoken with seems ready to believe a festiva only weighs 1300-1400 lbs to start, and they know they can remove 200-300 lbs of shit from their car. They just assume the power boost is because the festiva is so light and tiny, when it's actually heavier than a stripped CRX.

[lrcboi]

thanks for the help yea its really strict aye and we are 1 of 4 main racecar builders in NZ so we cant really cheat

can anybody answer 2,3 and 4 ?

im going to use b6 8v head