I've decided against switching to a 350 for the time being, so now I'm going to do some minor upgrades to the 305. First and foremost, I have an 89 Firebird Formula with an LB9, 700R4 trans, and 2.73 stock rear end.

Also, I'll be swapping my entire rear end to a 3.55 Ford 9". After some new bearings and the posi unit put into it, should be good to go.

Now, I plan on running everything stock, except exhaust, rear end, and cam. Maybe a custom air box too. Sould be getting the rear end prepped to go in about a week from now, so I'm moving onto upgrading the cam. This is what I'm looking at:

http://www.compcams.com/Company/CC/c...?csid=208&sb=0



I know I'll need to switch from factory 1.5:1 rockers to 1.6:1, and new springs. Will this cam work? If not, can someone nudge me into the general direction? Keep in mind I have factory heads. I also have the resources to get a chip programmed. The car is not a Daily Driver, but I do take it out a few times a week just to cruise around. I also want to race it on a regular basis. Also, what sort of times do you guys think it'll be capable of, with just a new cam + 3.55 rear gear?

Finally, might be looking into making a custom air box. But I don't even know where to start. Any suggestions? This is the space I have now with the stock removed:

 

A 9" is overkill for the LB9. It uses up more HP than a 10-bolt & well built 10-bolt will live up to a LB9, even with slicks & drag strip launches. I wouldn't spend the $ on a 9", if you are going to keep the LB9. Even if you plan on upgrading later, a 9" is overkill to be spending $ on right now.

 

I should have mentioned, the 9" is the full rear end assembly, and I'm buying it off a friend for $50. I was originally planning on buying a 3.42 Richmond, but that's $300 for ring&pinion + install kit. If I buy the 9" 3.55, all I need is new bearings. The rear end is good, friend is only getting rid of it because he went to a 4.56.

 

Use the money you were going to spend on the 9" rear end on a better induction set up to help feed the engine some air for that cam. And buy some header's to exhaust the fumes that cam will make. You'll be a lot happier with those 2 additions than an overkill rear end sucking power out of your new cam to turn the wheels. If you check the pinion angle and set up of your current rear end against the ford 9" one, you'll start to see where that power will get wasted.

 

Speaking of cams, do you think that one will work? Also that leads me to the air box question. From the pics I posted, you can see there isn't much room. Where should I go with it?

 

Also should mention, I plan on porting the heads eventually. Most likely this winter. I mainly chose the 9" because it's really cheap, and it has a good gear for both street and racing use. I'm aiming for 13s on the track. Need to get rid of the stock 2.73 gear one way or another.