i have a 84 z28 with a 305. it is a new rebuild bored fifty over, with a mild cam, edelbrock performer intake and an edl perf. 750 cfm carb. any help on what hp could be would help. it is connected to a 5 speed. i would also like to know what gears are on this car. i believe they are stock.

 

Without headers your motor isn't going to benefit too much from the cam. I would say 20-25 hp over stock, depending on the lift of your cam. Isn't 750 cfm a bit much for a slightly modded 305?

 

I'd say 170hp at the wheels.
My 86 LG4 got a huge boost in power when I added the Edelbrock 1406 600cfm carb to it. Had stock manifolds and exhaust. Ran a 14.94 @91.67mph.

I have a 5 speed as well.

Car is now a 305 TPI with headers, 3" Exhaust, cam, and other mods. I expect 300hp and 344 ft/lbs of torque at the flywheel.
I will find out soon enough when I take her to the dyno.

 

Too much carb. I personally feel that in mildly modified engines ,stock manifolds with free flow exhaust are just as effective as cheap headers.If you have a tach you can figuare yur rear gear by using RPM x Tire Dia. / MPH x336. You need to pocket port your heads to allow your mods to work.

 

There's no way a free flow exhaust can help when you got those restrictive manifolds on with a restrictive Y-pipe.

 

if your car is an origianal L69 HO car, you have 3.73 gears with your 5 speed. i suggest getting headers too, what are your cam specs? these 305s can be made to run.

 

I said in a mildly modified car and cheap headers,I've seen independent test that confrimed it. The off the shelf headers produced 12 more hp at 5800 rpm's than stock dual manifolds with the same pipes and muffelers as the headers.

 

I took my car out for a drive down the street today with open headers. First time I've driven her in 8 months.
Man was she quick, and loud as heck too.

So much torque, breaks my 275/40/17 tires loose without a problem.

I was a very happy camper today. Now I just need to get my y-pipe made and the rest of my 3" exhaust attached.