'69 351W build up options

[Steve]

I bought this 1969 351W for a few bucks since it was a great deal. I have been kicking around the idea of a 408 but also want to explore the option of building it up for the race class I will be moving into in the near future. Instead of going with C3 heads and such

Here's the rules...

9.5 lbs per rw horsepower
9.0 lbs per rw torks
Car will weigh 3050 or so with driver and a full tank
This means I can run 321 rwhp and 338 rwtks
Using a 15% drivetrain loss through a T5 and 8.8 --> 369 fwhp, 388 fwtorks

Any aluminum heads
Any type of cam
Any ignition
Any intake
Any exhaust

Obviously it won't take much to get there with a 351. I may need 6300 revs to keep the gearing I have.

What parts do you recommend?

Use the stock crank?
Eagle SIR I beam rods?
Which heads to make this power level? TFS too much?
Which intake?
Which carb?
Which cam?
Should I go with any block mods (ie girdle, 4 bolt mains)?

[Old Man]

This is a basic setup. For any class racing I would like to see more information, where do you want the tq range, what fuel is used, ect to pick carb and cam.
I would also recommend SRP type pistons to match your choice of fuel.


Use the stock crank? Yes
Eagle SIR I beam rods? Good choice
Which heads to make this power level? TFS too much? Very good choice
Which intake? RPM Air Gap
Which carb? 650-750 depends on use
Which cam? Need to know more about the intended use
Should I go with any block mods (ie girdle, 4 bolt mains) Your block is good to 600+fwpp, no mods needed

[Steve]

The fuel will be 92 or 93 octane. I can go with higher but keeping operating costs lower is a plus, no E85 allowed. I was thinking 10 to 1 compression and a hydraulic roller.

I would like the hp and torque curve to be a flat as possible, maximizing area under the curve. Peaky would be bad. There seems to be a way to figure out the perfect curve and the guys who have gone through the work (spent the bucks) to determine it, guard that secret. I need the engine to pull from as low as 2500 rpm in really slow corners and pull until 6200 or so rpm. Maybe a custom cam is in order. I just don't want to buy too much head, intake and carb and have to restrict back down.

[tls90lx]

Id go w/ a prosystems carb, TFS head, and a Jay Allen Cam

[theduckylittle]

I'm just doing some thinking out loud, it's very realistic that I should just STFU and go sit back in my 2300 corner.

Is a 351 really the best way to go? 400+ Cubes is nice, and I can definitely see where it might let you get away is a very dependable budget race engine, but the 351W does add quite a bit of weight right over the nose. It's also taller than a 302-based engine raising the front-ends center of gravity.

I'm just wondering if something like a 331 setup to have the snot rev'd out of it might be better for your intended application.

On Edit: Also, the 331 could have two rev-limits built into it, one for when you're dyno'd by the racing body and the other for when you're actually racing.

[Old Man]

I'm just doing some thinking out loud, it's very realistic that I should just STFU and go sit back in my 2300 corner.

Is a 351 really the best way to go? 400+ Cubes is nice, and I can definitely see where it might let you get away is a very dependable budget race engine, but the 351W does add quite a bit of weight right over the nose. It's also taller than a 302-based engine raising the front-ends center of gravity.

I'm just wondering if something like a 331 setup to have the snot rev'd out of it might be better for your intended application.

On Edit: Also, the 331 could have two rev-limits built into it, one for when you're dyno'd by the racing body and the other for when you're actually racing.

GO BACK TO YOUR 2300 HAIR DRYER CORNER.

You are correct the 351 will add about 50lbs to the front end. There are a lot of ways to cut weight up front if you want to correct this. A K member with lowering motor mounts set back 1" comes to mind.

You do not have to rev the snot out of a 331 to get 350+-hp 6200-6400 should do it. You will loss some low end Tq.

2 rev limiters would be cheating if you get caught.

[theduckylittle]

GO BACK TO YOUR 2300 HAIR DRYER CORNER.

I probably should ... I really need my new header to come in so I can bolt the new engine in before the white shit hits.

You are correct the 351 will add about 50lbs to the front end. There are a lot of ways to cut weight up front if you want to correct this. A K member with lowering motor mounts set back 1" comes to mind.

You do not have to rev the snot out of a 331 to get 350+-hp 6200-6400 should do it. You will loss some low end Tq.

The K-member also helps without the extra 50 lbs of the 351. I just figured the extra R's help with stretching out the gearing, add in some long rods and some AFR's and you could get a decently wide power band out of the 331.

2 rev limiters would be cheating if you get caught.

"What do you mean I can't change the pill?"

-Duck

[mg72]

Mildly ported Windsor Jr heads and an off the shelf comp cams split duration cam would probably be the most cost effective package. You would only want about 270 cfm intake/210 cfm exhaust flow and that would net you the 400/400 with a table top torque curve in your range. Agreed on the air gap intake and I'd say a 650dp holley over a larger carb.

[mg72]

Id go w/ a prosystems carb, TFS head, and a Jay Allen Cam

That combo would probably overshoot the required specs depending on the cam. I'd bet that would be hard to keep that combo under 450hp.

[Old Man]

That combo would probably overshoot the required specs depending on the cam. I'd bet that would be hard to keep that combo under 450hp.

That would depend on what you the Jay you want from the cam.

[Mullet Tuner]

Why not a stock LS1? It should drop a solid 75-100 lbs off of the front of the car.

[Old Man]

Why not a stock LS1? It should drop a solid 75-100 lbs off of the front of the car.

GO BACK TO YOUR LS1 CORNER.

[Steve]

Why not a stock LS1? It should drop a solid 75-100 lbs off of the front of the car.

Probably going to be illegal in the near future. There are LS1 foxes in the class right now.

FVCK It, this thing is going to be a 500+ hp 408. kinda seems like a 360 hp 351 is a waste of a '69 block.

[Mullet Tuner]

Probably going to be illegal in the near future. There are LS1 foxes in the class right now.

FVCK It, this thing is going to be a 500+ hp 408. kinda seems like a 360 hp 351 is a waste of a '69 block.

[Old Man]

Probably going to be illegal in the near future. There are LS1 foxes in the class right now.

FVCK It, this thing is going to be a 500+ hp 408. kinda seems like a 360 hp 351 is a waste of a '69 block.

Damn, I have to agree with kinda? If you want a 500hp 393, or a 408 rotating assembly let me know.