Okay last time I have 74 mav grabber with .30 302, long tubes, dual 2.25 inch exaust, 600 cfm holley with 289 eldbrock intake manif, stock heads and cam, msd distributer, aod tranny, hood scoop, 8.25 inch posi. HOW MUCH HP DO I HAVE ????
re yes i have yea i actually changed a lot of things to specify exactly what i have like stock heads and cam. This will allow anyone to specificly and precisely tell me how much hp i have without asking me a question about motor etc..... I appreciate the concern. thanks
There is no way for someone to precisely tell you how much horsepower you have without putting the engine or the car on a dyno. And even then the results can very between dyno's, state of tune and conditions. Another option is to run the car on a track and calculate the horsepower based on it's performance. Even then you have variables such as traction and weather conditions that can alter the results. Sorry but any answer that you receive to this post will simply be a best guess.
bingo just go out and have fun , who cares about numbers or you could take it out to total performace( i think the have a dyno) in mt airy , see what you get out of it
posi The previous owner made a "custom driveshaft" and he said 8.25 posi which I dont know how but i do know it has some form of posi
Using stock 302 heads, 8.5 compression, and the mildest cam I could, my desktop dyno said 236 hp. Keep in mind, this is with optimal tuning and a cam with about .035 more lift than stock. A '66 289 4v was rated at 225 hp and the '68 302 4v was rated at 230 hp. But they had a lot more compression than a mid 70's 302. You will make of some of that up with the headers and exhaust. I would guess you have about 220 hp at the flywheel. This may be more if your compression is higher. Like the others said, your AOD is gonna eat up a lot of hp on a rear wheel dyno. I bet you would only show 165 rwhp. The real questions you should ask are: 1. Does it run well? 2. Is the power where I can use it? 3. Does the power level match the intended use? My stock 302 Mav ran great with just a holley 500 2 barrel, dual exhaust, and a good tune. It would light up the tires at will and would chirp the tires going into second with a stock c-4 and 2.75 gears. Top end was 120+ and it got decent mileage on the highway. The horsepower on paper was low, but it was well tuned.
his .030 bore probably translated to a bump over stock compression but the stock heads and cam are really going to choke any other mods to the motor. the tall deck block and large combustion chambers means a lack in compression, plus its breathing through small stock '74 valves and the equally weak cam. all those external bolt on, carb, intake, headers... they really dont mean much if the engine isnt breathing
I'll spin the magic wheel!! Wow 500 HP!! Come on, how do you expect anyone to know the HP of your engine? There are so many factors involved, spend the money and goto a dyno and find the real numbers.
re dave All im looking for is a rought estimate. I dont intend to waste money on dyno now when i can do it later with all the add ons.
Cheapest way to get a ball park is to take it to the track.....make some passes, then use an "online" formula to get an idea. Get some time slips and I can get you in the ballpark of horsepower.
