Power estimate for a friends 289

[SadbutTrue]

It has:
289
.030 over
TRW pistions, 11:1
Roush World Products heads
Unknown cam, probably matches intake for rpm range... so say Compcams 284H
Torker II intake
Holley 750 DP
MSD 6AL
Headers - i think 1 3/4"
3" pipes into flows, dump

pic attached (edit: nevermind i lied)

 

[12sec67]

hard to say.....approx 300 at the wheels with a good cam and head porting.

exhaust is little too big! and trw's are heavy mothers, but strong!

 

[SadbutTrue]

hard to say.....approx 300 at the wheels with a good cam and head porting.

exhaust is little too big! and trw's are heavy mothers, but strong!

only 300 at the wheels with both of the above? Well... i guess the P.O. did lie when he said he estimated it had 450... Is there any minor detailing that could drastically change things? Like if the exhaust was 2.5"?

It has a toploader 4 speed too.

 

[GaPonyFarm]

only 300 at the wheels with both of the above? Well... i guess the P.O. did lie when he said he estimated it had 450... Is there any minor detailing that could drastically change things? Like if the exhaust was 2.5"?

It has a toploader 4 speed too.

I'd say 300 rwhp is extremely hopeful, probably closer to 250. This engine is way over carbureted and I'm no fan of the Torker II. Personally, I'd go with the Edelbrock RPM intake, holley 600 carb, and 2 1/2" pipes... You still won't be getting 400 at the rear, but you'll have a better matchup of components.

You will NEVER get 400 rwhp from that 289... not even close IMHO. That would require about 485hp at the crank! And if you do, you can kiss your crankshaft goodbye, along with your rearend, unless you've upgraded to a 9" posi with at least 31 spline axles. Good Luck though!

 

[Fostang]

To get 450 from that he's going to need way bigger heads I'm thinking at least 2.05 valved with some TEA porting on them mucho cam solid around .600 lift and 13.1 compression.

 

[SadbutTrue]

To get 450 from that he's going to need way bigger heads I'm thinking at least 2.05 valved with some TEA porting on them mucho cam solid around .600 lift and 13.1 compression.

Are these heads that poor? I had no idea. They may be slightly ported. What would 2.5" exhaust do to it? Like I said, we don't know exactly what cam he has in it, but its relatively hot. Judging on his intakes rpm range i used the 284 as an example.

What would this car, with 3.73, posi rear with kinda sticky tires and the aforementioned 4 speed run in the quarter? Its a 65 btw.

 

[D.Hearne]

I would also tend to agree on a 300 RWHP estimate. And also agree that a dual 3" exhaust is way overkill, 2.25" would be better. And that 750DP is also way too much carb. The 302 roller motor in my 89 Ranger had a similar cam, but a roller ( B303) heads were Canfields, compression was 9.8 to 1 and also had a Toploader 4 speed ( wide ratio) and 3.73 rear gears W/trac-loc and it would run high 13's ( this is a 3800 lb truck with driver) This motor was about 400 hp ( flywheel)

 

[none67]

well its hard to estimate the hp, but i can tell you that this thing is prolly made for high end... 750DP- really sloppy low end, nice high rpm power - 1 3/4 header with 3 inch exhaust- ouch, good bye torque

 

[SadbutTrue]

how much would he gain if he was using 2.5" pipes? He isn't sure on the size, he just said 3. I would bet on 2.5 in actuality. And yeah... the heads can't be that bad, are they?

 

[2bav8]

Not sure on the HP, but its less than my 5.7L

And we won't even mention torque curves...

 

[12sec67]

in short...
aftermarket aluminums would be better then the heads you have.
2.5" piping would work well up to 350rwhp-400rwhp.
you might want to go to a 650dp.

 

[SadbutTrue]

well, desktop dyno is giving 450 hp, 375 lb feet. Of course this is considering a run of the mill single plane (which i hear the torker II is not), wedge/pocket ported stock valve size heads (those seeme dlike the closest option), guessing the cam profile (though it doesn't seem to change much) and assuming the exhaust is optimal.

is it that far off

 

[GaPonyFarm]

Without having exacting specifications on your components, Desktop Dyno is useless. I ran more conservative items for what you had mentioned and was getting 260/243... So specifics do matter! I'm sure you're doing much better than 260, but you will never, ever, ever, get 450 hp out of that engine... never, without a blower.

Its not that your friend is using bad parts, its the way he's using them. Horsepower/Torque is built by matching components that work best together. You can get the biggest carb, hottest cam, and most expensive heads and end up with a real piece of crap.

You'll probably do 15's at the track...

 

[SadbutTrue]

Any suggestions on a part that might be out of sync with the rest of the combo? I know the heads aren't the best, nor is the intake.. but i wouldn't think that would hold him back over 100 horsepower or so. I also heard somewhere, might have been ratio411, say that 289s love overcarbing. Its also built for top end, hence the large carb, cam, and single plane.

For the record, i never thought it would approach 450. I realize thats a ton for a 289. One guy who just joined the forum though, his screenie is hot_rod something, has a 289 at 405 hp though with 351w heads, i believe. We were just trying to see where it was. I was expecting about 350 or so. Wish i had more exact cam, compression, exhaust and head specifications, but alas.

Thanks

 

[10secgoal]

Gapony is right. Parts have to match to really get the HP. And yes you can lose 100Hp with the wrong parts. Basically it boils down to.... Your heads and cam make all the power. The rest of the motor will compliment them. I would get a smaller carb 600-650. And definitely junk that torkerII. I had one then went to a rpm air gap. Outstanding difference.

 

[D.Hearne]

There's nothing wrong with Roush heads,( Jack Roush didn't get to where he is now by doing inferior heads) they're as good a head as most of the aluminum offerings. And they're not even close to breathing in terms of stock iron heads, they're way over that. And his 65 should have no problems with 12 sec quarters with that combo. All I was saying was I thought the 750 carb and 3 inch exhaust was overkill. The rest of his combo is right up to snuff.