What is the most HP you can get out of a naturally aspirated 351W

[69 Mach I]

The guy building my car proposes pulling the engine, hot tanking it, and rebuilding it with Windsor 200cc alum heads with 64cc combustion chambers that he will have ported and polished, a crane cam and speed demon carb to be matched after flowing the heads, forged Eagle IBeam rods, Probe flat top forged pistons, and new roller rockers. This will give me 10:1 cr. The engine is already bored .030 over and I have new coated Hedman long tube headers leading to an X pipe and flowmasters. They tell me I might expect about 385 flywheel HP. It seems to me that I could be getting more out of this engine but where and how?

Any ideas?

jS

[Tony Radford]

JS, you'd probably end up with a nice reliable street motor, but no where near the Windsor's max HP potential. Take it from me, stroking is where it's at. I was running a 400+HP Windsor (crank HP) and recently upgraded to a 427 Windsor stroker. WOW! A number of the Cobra guys here in the Atlanta area are running 396 Windsor strokers and love them. I wanted to match the badges and squeeze a few more HP. You should SERIOUSLY consider a stroker.

[69 Mach I]

I just spent 14 large on the car, another 7 for a global west stage 5 suspension (wilwood brakes, vintage 45 wheels, etc), nearly a grand on new tires, 1200 on a TCP manual rack, other nick nacks adding up to another thousand, then the new headers, new exhaust, and the labor to install all of the above. I still have to put this thing on a boat and pay the transport, taxes and duty on it when it gets here.

I'd stroke but I am seriously over budget and in deep serious with the wife. There is what I want and what I can afford to do. I have decided to get the best build possible there with the meager amount of money I have left to work with. Can I get over 400 hp out of the windsor without stroking, a blower, turbo, or NOS?

jS

[Ron61]

I can't tell you for certain that you can get over 400 horse out of what you are doing but I think it should be in a reasonable range. You never said if you are upgrading the intake manifold and if the car is to be just street driven or ran harder. A single plane intake will help but you will give up some low end torque and driveability. I don't know what kind of gas you have access to but if you could raise the compression a little that would help some but not a huge amount in your case. Since you don't plan to go the stroker route, I would hazard a guess that the engine builder is pretty much in the ball park with his power estimates.

Ron

[John McMahon]

Members of Club Cranky have 351Ws putting out 490HP to 600 HP.

If you put the time and effort into the top end, that is where you'll make most of your power....porting and polishing on a good set of aluminum heads and the correct intake.

...flow...flow...flow yer heads, gently down the stream, merrily, merrily...

[69 Mach I]

I should have mentioned that the car already has an edelbrock Torker II intake. The shop says it will spend a lot of time working on the heads. I don't know why I am fixated on 400 hp. It is just a number. What I really want is a 0-60 mph torque monster.

Whatever the outcome, I know that I will have a completely rebuilt engine that has been taken apart and reassembled by some real pros with top notch components. I might add a blower later on when I get some more money. Holley tells me I can use a 302 roots blower on my 351W if I use an adapter plate kit from PME.

thanks for the input so far.

[brainsboy]

You should be pretty close to what you want. I am assuming your using the worldproduct dart II heads or the roush, they are pretty good heads. With these heads you need to work on the intake ports, the exhausts flow pretty good with mild porting, once you put a little bit of work into the intakes they really come alive.

[John McMahon]

Mach,

400 HP should be easy to attain. I bought a stock bottom end 351W in eBay for my racer, with World Product aluminum heads. I took the Victor Jr intake from my old moder and it made 412HP on the dyno at the flywheel.

[V-8]

Hey 69 Mach I;
Mine old combo was:750 holley dp,victor jr intake,TFS tw heads,9.3:1 comp ratio,speed pro forged pistons 13cc cup,Comp Cams Xtreme energy cam 541-544,240-246 0.050,110lsa,Crane roller rockers,SPEED PRO rings,DUI ignitionstock crank,block,rods.
Weight of the car 3222+200.Rear ratio 4.11 8inc.Convertor 2500 stall.Tires 245/60/14.0-60mph 4.9sec 0-400m 13.02s 115 mil.Dyno 380hp 5800rpm,501nm torque 3800rpm.No slicks!
When i use 200hp nos cheater plate shot with this combo i was faster than HONDA CBR 600F

[V-8]

After that combo i changed some parts:10.5:1 comp ratio ROSS pistons.Comp cams mech roller cam 242-248 0.050,608-614 lift,110 lsa. 245/45/17 Kumho radials,3.55 rear gear.Weight of the car 3322+200+250pounds.0-60 foot 2.52 0-60mil 5.1s,0-400m 12.7s.No slicks!

[Ron61]

Mach,

I just received my March issue of Hot Rod and was reading their article about the cars to be used for the new Starsky and Hutch movie being shot. This is from page 22. Bob Lambeck assembled two Windsor V-8s bored .040 over for 360 CI. He used scat forged crank and rods, SRP aluminum pistons, Edelbrock RPM Air Gap dual-plane intake, Edelbrock Performer heads with a Holly 750 carb. Comp Cams hydraulic roller cam and MSD ignition and 9.7 compression the engines made 435 horsepower. So you should have no problem at all getting your 400 plus horsepower.

Ron

[RACER X #99]

Just to answer you most hp question.
The Nascar cup guys are getting over 700 hp and some are claiming almost 800 hp. Of course these are not exactly 351 W's and they all are 358 ci. They are definately not streetable.
Cranky

[Ron61]

Cranky,

Now that Union 76 has stopped supplying NASCAR with gas, what brand do you use? All I seem to be able to find around here is the Unical and they tell me their 110 is the same as the Union 76 was. Have you used both and did you notice any real difference in them?

Ron

[John McMahon]

Ron,

Race gas is race gas...as long as the octane is there, who cares?

[Roscoe]

Those 600 hp Club Cranky moders are Dart Blocks. I guess you could get that much out of a modified stock engine but I wouldn't push it too much.

Roscoe

[Excaliber]

Do you think the Dart block helps gain horse power? I would think the Dart block is more about increased strength and durability.

As far as cubic inches go: I would NOT want my 351W taken to the extreme of 427 cid. Thats really pushing the envelope of durability.

Ernie

[scottj]

Originally posted by Excaliber


Do you think the Dart block helps gain horse power? I would think the Dart block is more about increased strength and durability.

Ernie

Ernie,

Yes, stronger blocks will increase HP. Joe Sherman, winner of the 2002 Engine Masters, has done extensive dyno testing on this subject. The Motown block he used to win the E/M competition is good for 20 hp over a weaker stock block with no other changes.

One of the reasons the aluminum Ford (small block) makes more HP than the aluminum Chevy is because it is stronger. Development of the Chevy was driven by Sprint Car racing to be very lightweight where Ford's development wasn't. This is according to Jim Kuntz- Kuntz and Co.
Scott

[Excaliber]

Scottj,,,,,,very interesting! I wonder if it has to do with being able to hold better more accurate clearances under the high rpm/stress of big horse power?

As for NASCAR gasoline, I thought they were running "pump" gas, not "racing" gas? I don't know about the mainland but there is NO place you can buy "pump gas" here that is over 101 octane. I heard a "rumor" that you could buy 101, but I've never seen it! 94 is about tops.

Ernie

[scottj]

Originally posted by Excaliber


Scottj,,,,,,very interesting! I wonder if it has to do with being able to hold better more accurate clearances under the high rpm/stress of big horse power?

Ernie

Yes it is, although Sherman's winning engine only turned 6500rpm. It did make 605 hp from 366 cid, flat tappet, on pump gas.

[RACER X #99]

The Nascar Cup cars use 110 octane leaded gas. That is the same stuff that I use.
For a while the Craftsman truck series were running 9-1 motors making less hp but able to run pump gas.

Everybody that I talk to running 10.5 and higher and doing track time is running race gas.

I know their are lots of guys running 10.5 with pump gas and thay say their engine runs great. THEY AIN"T WORKING THEIR ENGINES.


Cranky