...this should...keep...them open... with...400+HP...you will need... ...roller block... ...transmission work/cooler... ...traction control...(f/c...t/b) ...tq. converter...(auto) ...tires/rims... ...radiator... ...gauges... ...fuel feed upgrade... ...etc./etc./etc. ...JMO...... Frank...:Handshake
THE first thing he'll need to achieve 400 hp with a 302/331/347 bottom end is aftermarket heads. Without that, it ain't gonna happen. As far as how stout the bottom end needs to be, the strength, lessens with the increase in cubic inches. The longer the stroke, the lower in the rpm range the horsepower will be made.
I love these threads where every poster has a different opinion. The amazing thing is that none are totally right or wrong. People have gotten different results with different combos. It's possible for him to get over 400 FWHP without aftermarket heads or spending over $7,000. It just won't be very streetable. A 302 that is bored .030., uses the first generation 351W heads (with a lot of porting), has a cam with a duration of around .294 or more and .550 lift or more, a high flow dual plane intake, and 750 cfm carb will get him close. But, to get over the 400 HP mark, and here's what really kills the "streetability", he will need a compression ratio of over 11 to 1. I ran this similar build in a 289 bored .060 in the '70s. However, 100+ octane gas was still available at the local gas station. I also ran a solid lifter cam and my vacuum sucked or should I say, didn't suck. No power brakes or A/C - the only vacuum needed was for the tranny. The good news is that with today's heads and roller cams, he can achieve over 400 FWHP, it be very streetable, pump gas friendly, and very dependable. It just won't be done on a shoestring budget. In fact, I don't think it can be done for much less than what this crate engine from Summit cost and it comes with 50,000 mile warranty. I'll bet this engine is close to Craig's and Frank's engines in HP numbers and cost. http://store.summitracing.com/partdetail.asp?part=MLL%2DBP3471CT&view=1&N=700+
IMO opinion...... I would run a 331 kit....... Great rod ratio..... any decent set of after market heads...... easy 400 plus hp..... unless you want mad rpms Hyd roller cams are easy to maintain and make great power......without all the duration...... roller rockers.......
Hydraulic rollers are good to 7500 rpms. Don't know about higher though. My 331's got a Z303 roller and stock style lifters (but they're Crane's) and it's been to 7500 many times. The stock lifters in my Ranger float at 6000.
I guess being a little on the cautious side I wouldn't recommend that high but 6800-7000 is no sweat with the right valve train components..... Mine floats the valves about 7200rpms with a E303 Ford factory lifters(new ones) but heavy retainers, and not so stiff valve springs... Since the all aluminum 347 clevor is gonna take a while to get done(read lotsa money and small budget) I decided I might try and pick up a Z cam port the heads/ shave them a tad more to get to 11 to 1 comp ratio add a victor jr intake and let her sing.... Hoping to get down in the high 11's all motor
Judging from watching the lifter retainer hardware cycle by turning everything on the engine stand, the Z303's lobe lift is about the limit for this stuff. The springs on the Canfield heads are the ones Canfield sold em with, I don't recall the exact specs, but the open pressure was around 350 lbs. I used the same set of heads on a 302 short block before the 331 but with a B303. It too would rev to 7500 without problems.
The 331 did 13.70's in the 3800 lb Ranger (Toploader 4 speed with a 3.73 rear, 28" tires) and so far with about 6 passes, it's gone 13.14@106 in the Comet. And I'm far from an expert in 1/4 mile driving. The 60' times were in the 2's, I've since swapped from the 3.40 geared 8" (with mismatched tires) to a 3.50 geared 9" with 265/50/15's, ain't had the chance to run it at the track again yet. I know there's more to come with it.
400 HP is my goal too. Although I'm going to spend the money on the bottom end (crank, pistons, rods) first. I want to use AFR 185cc heads but I can always put them on at a later time, with the engine in the car! These are all things to think about when building an engine. Because I am not a fan of pulling an engine in and out of a car, althought it will be alot easier now with the Mustang II installed! I want to do it one time and thats it. IM like you I dont have the money to buy spend on the rotating assembly now, but save up. Mixing more than one manufactor on anything with a build = headaches! I've learned save up and buy, dont mis-match! You'll spend more in the long run if you do. This from a 27 y/o who likes the least amount of stress in his life as possible!
For a street /strip engine the RPM is a bit high for the street. An engine that turns to 7500 won't idle at a speed that is below the 20 mph limit in some places with a 3.55 gear in it. It also has to be loping like it is only running on 3 of the 8 cylinders at idle speeds.It would seem to be a track car that you are going to try to drive on the street. It isn't going to get a high grade for manageable driving on the street. (assuming that the cam produces maximum HP at 7000 to 7500 RPM)
It can and will idle & drive comfortably and still pull to 7500. Mine did. My Ranger has 3.73's with a Toploader 4 speed and 28" tires. That ratio tranlates to 3.50-55's with 25-26" tires. All it takes is a roller cam.
I did say "assuming that the cam produces maximum HP at 7000 to 7500 RPM" There is a difference between pulling to that RPM and getting max HP at that RPM.
Now you're splitting hairs. Still no reason you can't have both the driveability and idle with a roller cammed 400 hp 302.
I made 496 hp at 7500 rpm with a stock bottom end, balanced with arp rod bolts, crane fireball heads and a solid lifter cam,and a set of used forged flatop pistons. over 100 pases and the bottom end looked like new. sold the eng several yrs ago, and last yr it surfaced still doing the job. the point is you don't have to spend lots of money to have a 400 hp reliable street eng.
