matt smash

Hi I'm trying to figure out how much power I can possibly get out of my motor. I am sticking with this motor, as I have spent alot of time etc. On it already.The following email sent to AFR gives insight to what I'm thinking about:
“
PURPOSE
Purpose.......... Street Only

INTEREST
Interest..........Chevy Small Block

ENGINE
Type Of Head..........Stock
Displacement..........305.38 in3
Bore..........3.73
Stroke..........3.48
Piston Type..........Flat
Desired Compression Ratio..........9.5:1
Combustion Chamber Volume..........625.53
RMP Range Start..........Idle
RMP Range End..........6000
RPM Range Max..........7000

INDUCTION
Induction..........Carburetor

MANIFOLD
Manifold Brand..........Edlebrock
Manifold Manufacturer's Model..........71014
Manifold Type..........Dual Plane

POWER ADDERS
Power Adders..........No

CAMSHAFT
Inatake Lift..........0.495
Intake Duration (adv)..........270
Intake Duration @0.050..........218
Exhaust Lift..........0.502
Exhaust Duration (adv)..........276
Exhaust Duration @0.050..........224
Camshaft..........Roller - Hydraulic

IGNITION
Ignition Manufacturer..........HEI
Digital Ignition Box..........No

EXHAUST
Head Pipe Diameter..........1 58 primary tubes jegs
Muffler Type..........Street
Exhaust Type..........Shorty Headers

DUEL TYPE
Fuel Type..........Pump Gas

VEHICLE
Vehicle Make..........Chevrolet
Vehicle Model..........Camaro Iroc z
Vehicle Year..........1986
Vehicle Weight..........est. 3500

TRANSMISSION
Transmission..........700-R4
Rear End Gear Ratio..........2.73
Rear End Tire Diameter..........16 tires
Number Of Gears..........4
Transmission Type..........Automatic
Stall Converter.............2800

Additional Comments.......Various techs have informed me I could get anywhere from
320 - 330 hp as the motor is right now. Current compression is 9.3:1.
Just got done with this build and all the ports have been matched
pistons as well. Will eventually change rear end gears. Camshaft its
COMP CAMS 08-422-8 the complete cam kit and their rocker arms. I am
not certain on the piston type. NOTE: THIS BLOCK was originally an EFI
out of an 88 with an M5 trans behind it.
"
What should I expect from the engine as it is right now?


This power # is for bhp. CAM may be good up to 6000rpm (add 500 according to Comp since its a 305. This will be a daily driven car.

Is that enough hp. (keeping in mind it's a street car)

five7kid

iTrader: (14)

The intake manifold drops off at 5500 RPMs. Winding it any tighter than that will not increase power. So, you might be in the 300-HP range now at best.

"Street only"

"400 HP" (Can we assume you mean gross at the crank?)

"Dual plane intake"

"305 cubic inches"

These things just don't go together without a power adder.

matt smash

What are you meaning about the "street only" comment. Is 300 hp a good amount for this car.

This will be my everyday car. And my carb is a Holley 570 street avenger which allows up to 300hp. So I'd be happy with that.

I was wondering what difference AFR heads would make.

Procharger told me they have an application I can get and should expect up to 550hp, which I find hard to believe.

If you can please clarify that would be great

NagleMac

iTrader: (1)

I believe that building a 305 with that much power will not be a very streetable car. I would NOT buy afr heads for a 305. If youre set on changing heads get a cheapo pair of "made in china" heads because AFRs will be a huge waste of money.

Adding a procharger with your compression that high is probably not a good idea, especially with stock internals.

Im not telling you to ditch the 305, but definetly don't waste your money on heads like that because you'll never use them to their full capacity

matt smash

Thanks for the input NagleMac. The heads I have are stock, but they've been machined and matched to have the least restriction possible. I just don't hear much of a 300hp 305 and have yet to fire her up.(still dealing with car's wiring harness) I guess I'm just afraid of being disappointed after all that work.

Oh yeah. The actual compression of my motor according to GM is 9.3:1

If anyone has anything to say please feel free and thanks for the feedback

NagleMac

iTrader: (1)

Thats the main reason I wouldn't get top of the line heads like AFRs, because the only thing you'll get out of them is disappointment. Don't get me wrong, those stock heads are junk, but there's no reason to but something like AFR's, trickflow's, etc. I would buy cheap bare heads, and use quality springs, valves, etc.

matt smash

Ok. I'm using Comp Cams lifters, springs, rockers, retainers, and timing chain. (Their whole kit). After reading what you said, the only thing that will get me to do any more head work is if I luck up on bare aluminium heads.

Thanks

robertfrank

iTrader: (27)

If you're dead set on building a 305 just find a set of ZZ4/aluminum L98 heads and do a mild port job on them. Or find a set of Vortecs and mill them down with a matching intake. Honestly I went down the "I only want to build my 305 for 300hp" road and while it made for a fun car, I wish I wouldnt have wasted my time on it. Please take some advice from someone that has been there. Just find a 350 and start from there. I promise you you'll be happier that you did.

matt smash

Thanks robertfrank. I actually am done with all the engine work. I just have some wiring to figure out. I just didn't expect to go so far with this and wanted to see if there was anything more I could possibly do.

blaze15301

I drive a 83 with a 350 with about 375hp its great for the street.I have lots of power when i want it and i dont do to bad on gas.

five7kid

iTrader: (14)

I see you modified your original 400 HP goal. Which begs to ask how you came up with that number.

300 HP is a very good amount for that car. Especially if you've never driven a 3rd gen with 300 HP.

300 HP 305 would be much more streetable than a 400 HP 305 (assuming no power adder).

Wouldn't be my choice, but probably okay.

Not hard to believe. But, you'd better have a stout lower end (forged everything).

Orr89RocZ

iTrader: (20)

Afr doesnt make a head to fit a 305 anymore. Too large valves

You want ported vortecs ported 113's or trickflow 175 small bores

Or find a set of race saver 305 class brodix or all pros

Cam it up, more lift and better intake, better headers. Should get well over 300 there

Ozz1967

iTrader: (4)

World Products makes a set of Torquer 305 heads that are supposedly pretty good for a 305.

You can also look at Super Chevy Magazine 350hp 305 for inspiration.

mcafee89formula

Forged all lower end. New aluminum heads with all the goodies. Hot cams H beam rods, a set of Mahle or JP Pistons. Then I'd get a ported edeldbrock intake manifold. Then your gonna get a twin turbo setup. Intercooler, blow offs, the whole works. OR you could slap a good ol American magnacharger or vortec supercharger on it and that otta give you close to 550hp at the wheels. Throw in a bottle of NOS and you'll eat most f-bodies for breakfast. BUT before you do all that have your block baked, fluxed, and bored 30 over and have your 2 bolt splayed to a 4 bolt with a one piece rear main seal for lower maintenance. Bad way to blow about 15 grand. I'd start with an L98 block and splay it into 4 bolt and build from there and go STROKER!!!!

Sent from my iPhone using IB AutoGroup

matt smash

Thanks for all the feedback. This is my first car (of course not the only thing I've driven) I've driven more powerful cars but keep in mind I'm driving this every day and at age 22 I still have plenty of time to put in another motor some years down the road. Let's see 383 maybe 402 lol. I'll see if I'm still up (or able) for that when I cross that path.

matt smash

Five7kid. I read from a post somewhere someone got 400hp, which is where my thoughts of those crazy numbers came from. I was originally on a budget so I stuck with this 305 that I was told was rebuilt when uhh got the car. Rebuilt my a$$. I had to replace the bearings and hand polish the crank. Took the stock heads and cleaned & machined all the journals as best as I could. Also had the pistons cleaned up. For the whole comp cam kit & roller rockers, etc. No longer stock. However I am greatful to have this. I'll see if I can get a pic on here.

matt smash

Hope this worked. My first time attempting to get photos on here via photobucket

five7kid

iTrader: (14)

I can't see them.

I usually load them from a non-mobile computer, seems to work better.

Restrorob

iTrader: (7)

Here ya go Matt...... SUEWEEET !!!

















I wouldn't want the job of keep'n it cleaned......

matt smash

Thanks bro! I appreciate it

Everyone have an awesome Thanksgiving

-Matt