Dose anyone know how much i can expect to get out of this combo?
8.5-1 compression,
perfomer intake,
stock c-heads
750 Q-jet
not sure what cam yet any ideas?
this is not a daily driver so i dont mind a rough idle
any ideas would help a lot this is my 1st BBO 455 build

 

300-350 maybe, can't put too much cam in it with only 8.5:1. Need 9.5 or better to really have it perform.

 

My advice is to build the engine around how much HP you want. That will determine what parts to use. If you dont have pistons yet should consider raising compression. I would hate to see C heads wasted on a low comp engine. Good luck, Rob

 

how do i raise the compression w/o new pistons? the heads are going to the machine shop as soon as they arriver here. the motor i got just got rebuilt 1000mi ago but the builder reused the stock pistons. i wanted to see if i can make about 400-500 hp . is this a crazy idea?

 

I don't think that would be possible with those stock pistons. Oldsmobile changed the CR on their engines by using different pistons so you don't have many options if you aren't going to change the pistons.

 

Is the engine out of the car? if so and you have the heads off already then now is the time to change the pistons to a higher compression forged piston. That's the only way your going to get there with out adders like nitrous, super charger, of turbo charging.

 

dang i thought that would be the answer. well i havent ruled out nitrous.the engine is still in the car running great . im waiting on the heads and intake. i might pull the engine and trans to do everything at once including a cam . any ideas on a camshaft ? i was looking at one from mondello (jm-20-22).

 

You'll need to cut them in excess of .060 to get anywhere near 9.5, which is what you'll need to be able to use enough cam to get you into the 400+ range. Not sure milling that much is a good idea.

You'll also need a flat tappet cam in the 240@ .050 range or a roller in the mid to upper 230's. Plus headers and good machine work. It can be done relatively easily, I made 465 running fat with stock C heads and a roller with a Performer. Just gotta have a plan.

 

ok thanks for the info. great help . ok well im choosing to change the pistons and do it right. im not so sharp with cam shaft selection so any help on that wouild be cool like what brand and model?

 

flat tappet? uhh not sure what that is sorry please explain. i feel really smart hahaha

 

Flat is a conventional cam/lifter, Solid or Hydraulic. Then you have Rollers, Solid or Hydraulic.

 

ohh ok thanks . probably stay with the flat. looks like a big cam . do i need to do anything secial to the valvetrain or can sock parts handel a cam like that? 240 @ .050 sounds fun

 

1. im working on a parts list so i can have all the parts in when the heads arrive. any ideas on the parts and what kind of work the machine shop needs to do to support 500hp would be helpful thanks

 

im now planning to upgrade to 9.5 pistons. any new ideas?

 

Yes if lift stays reasonable. 240 @ .050 will sound fun.

What octane fuels are available in Hawaii?

 

500hp may be a bit optimistic but main studs and ARP rod bolts are always a good idea. Proper bearing clearances will be important as well.

 

With stock low compression pistons? Yes......By the time you mill the heads enough to make any HP they will be worthless on any other motor......

I say run it like it is till the funds or motor says its time for a rebuild......

I would guess 275HP ........Still enough to smoke the tires at will if need be......

Reread the parts list.......

My combo..... http://72.22.90.30/phpBB2/viewtopic.php?t=12112

 

92octane is the highest we got

 

holyMan! BIGJERR your ride is killa! i want my car to do that.

 

what would reasonable lift be? sorry i really dont know too much about cams

 

I'm with Jerr, 275 HP.

 

Around .500.

I think he could do better than 275hp. You have to figure they were rated at 270 in '72. If you add headers and a little more cam, 300 isn't out of reach, even with only 8.5:1. JMO.