proud owner of a 1967 mustang need to know about super charging

1967 blackjack · 09-20-2009

hi I am the proud owner of a 1967 mustang with the 289 stock motor no performance parts I am rebuilding the motor and I am thinking of superchargering it. is a stock 302 crank strong enough to hold up to a supercharger and what about rods what do i need

**stlwagon** · 09-20-2009

Welcome to AFM... Let's look in here for answers.

Jonk67 · 09-20-2009

Not an engine builder but for boost I think it depends on how much psi of boost you plan to run the motor at. If you're staying modest streetable the stock crank may hold up, I'd have the rods shot peened I believe it is and use ARP rod bolts in place of the stockers. An engine girdle may be in order also but that's debateable, I read that it only keeps the parts in one place when the mains break...

Be sure to get forged pistons and pay attention to your compression ratio, it needs to be low ~9:1 or lower to avoid detonation.
You will also need a blow through carb. unless you're going EFI.

I would buy a book on superchargers at Barnes&Noble etc. and start reading or speak to a reputable engine shop before buying parts or prepping the block.
What heads are you running? You didn't give much info on the engine.
Jon

1967 blackjack · 09-21-2009

Well I cant tell you much. All I know is that it is the base 289 not the high output motor I pulled some information off the intake first line is 289 E-236-A second line is H E-236-A if that means anything. I have done slight modifications to the car nothing to the engine yet and a better question is could a stock 302 crank hold up a super charger and yet live a long life like 200,000 miles and I am thinking about running stock heads but getting a valve job

Jonk67 · 09-22-2009

Yes I think a stock crank could survive on minimal boost, reconditioned of course (micropolished, chamfered) and if you keep the compression down and don't push the engine (lot of 1/8mi., 1/4mi. runs, hardest racing on an engine) you may squeeze 100K+. Couldn't say if it would go 200K or not.
You'll be choking the engine if you keep the stock heads, they have emissions bumps in the exhaust ports that ruin flow and the passages are small. An engine is a big air pump - air in > air out. With the SC you'll be forcing more air in faster but not be able to get it out, I would guess you would burn valves pretty quick or blow the rings from the back pressure. Imagine training to run a marathon for a year and then breathing through a straw while running.
There are numbers cast into the engine to tell you the basic year, they're on a ridge just above the oil pan all the way to the rear on the pass. side. You have to take the starter to see them and probably have to clean them off with degreaser and a toothbrush. All you need to see is the first 2 characters C6='66, C7 = '67, etc.
Jon