400hp SB, to go the 289 or 302 route?

Lately I have been thinking of doing a number on a SBF for street duty, but I wanna be in the 400fwhp range. As things are now I can either go with a 1986 302 to get the job done, or a 66' 289. For the most part all the internals will be stock, but in either case I will buy a set of forged pistons as both motors would need to be "freshened up". Here is where my choices get difficult - heads will most likely be TFS TW, AFR's are more than I want to spend... The exhaust on my car is up to the job, and on the intake side it will either be a weiand stealth/demon carb combo or Edelbrock Pro Flo EFI. My major difficulty is in displacement and cams. If I use the 302 I'll use a hydro roller and probably have a total displacement of 306cui, if I go the 289 route I'll do a 15 thou overbore, and go the way of a solid cam (roller, I think?). Any input is appreaciated, but as things are now I feel the 289 would really lack in the low end grunt to make the HP quotea - As I'm sure a few of us have 'been there, done that' I'm curious to hear your views.

always take the cubic inches, it will make it easier.

I've always though that if you have identical builds on a 289 and 302, they will both make about identical horsepower, but the 289 will do it at about 500rpm higher, and thus will make a little less torque. But that slight lack of torque would be made up for with slightly lower rearend gears, so either way it's a wash. I went the 289 route just because I had a hard-on for old-school horsepower. But if I didn't have any preference between either, and was just looking for the easiest way to get the most power, I'd go the roller block 302.
When I first started my buildup I was looking to hit the 400hp mark.. but the more I got into it the more I realized that 350-370hp was probably a lot more realistic for a street machine. To wring out that last 30-50hp, I would've had to go with a bigger intake, bigger cam, and bigger heads, and would've lost a lot of power below 4000rpm.
For you to hit the 400hp mark, you're probably gonna have to spin a 302 up to 6500-7000 rpm, so you might want to at least look into getting some good aftermarket connecting rods and a good crank. When you've already got over $5K into an engine, and extra ~$500 for a good bottom-end is cheap insurance in my mind.
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For what it's worth, I agree with motorhead. That 400 (w/o NOS) is really pushing the 302 platform into race territory. Forged cranks are the way to go there, maybe a Scat. This little 302 is made to hum versus grunt. Short stroke is just that way.

89 GT mustang long block (used)
Edelbrock Performer RPM heads, some porting, all ports and bowls smoothed.
1.90 intake valve size
1.60 exhaust size
RPM intake
650 Speed Demon, 78`s front, 88`s back
JBA shorty`s, 2.5" exhaust, Dr. gas "X"
Windage tray
stock oil pump
serpentine w/ underdrive pullys
cam is middle of the road
.540 @.220 in.
.566 @.224 ex.
110 lobe seperation

Best pull on the dyno netted 344.1 at the tires, which is about 400 or so at the flywheel. Nothing race about this setup. All the stuff just seems to work well together.
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Damn Nastystang, 344 at the rears? I'd say that's probably more in the 420hp range! You're right too, that looks like it should be a pretty streetable setup. I honestly don't know WHAT my engine is putting to the ground, both dyno programs I have estimate it at about 370hp... but they also estimate your setup at ~375hp @ 6500, so who knows...
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joe sherman did one like what youre trying to do a few years ago...made 404hp. it was a 306 with 289 rods.ported 289 heads with 1.90s and 1.60s...and a hydraulic isky 280 mega cam, and a victor jr intake, 750 holley. it was in an article in one of the car magazines. hope that helps. Duke

I gotta say I'm really agreeing with you on this one. I like the 302 route because I can go with a hydro roller which is great for power up to 6000rpm - this I like. Also it being a street motor the 289 has alot less practical rpm band use because of its higher winding nature, and in turn greater stress on the bottom end. As well 400fwhp may have been a little excessive for sure, but I'm confident if I pick a COMPLETE PACKAGE i.e cam, torque converter, rear gears, etc. it should be a real nice runner and not too hard on the factory bottom end. But make no mistake I might yet get a set of eagle rods and a nice crank as Motorhead said "just for cheap insurance". And as 67 Stang said in a few more words "there's no replacement for displacement"[img]/phpBB/images/smiles/icon_biggrin.gif[/img]

<font size=-1>[ This Message was edited by: 2FST4U on 3/15/03 6:30am ]</font>

nastystang,
Do you remember what rpm your peak power was at? I plan on running a 224-230 108ls, I would like mine to be at 6100.

the sherman article can be found at fletch's carburated 5.0 page