331 cam
 

I purchased a Dart 4.00 bore Aluminum block to have an open track/ street motor built for my FIA.

331
10:1
7000 rpm
Solid Roller
Weber 48 IDA
AFR 195 Heads
Jesel Valve Train
Eagle Forged Lower

I took a look at the specs for the Inglese Weber cams and have spoken to Comp Cams about grinding a solid roller for the Webers. The tech said they were unable to reproduce the hydraulic spec for the solid as he uses a different cook book to build solids.

He wants to use the XR280 as the basis for the new cam.

242-248 0.608-0.614 115°

For comparison => Inglese Stage 2

222-224 0.571-0.565 115°

Is the increased duration and lift of any concern with respect to the Webers?

x-cliff

The extra lift is desired, but a 20 deg duration difference is huge. You also don't want a huge duration split because it increases overlap.

It would be best to contact an engine builder for the cam. Ive never had much faith in tech guys.

I can have Comp Cams custom grind any cam for me, with me picking the lobes. A solid roller with similar performance characteristics can be made, with adjustments for lash. Of course a solid roller would have the potential for more aggressive lobes and possibly more power.

Have not talked to the builder yet - gathering info so I can intelligently talk to him. Appreciate the input.

chr

Just curious...why not a hydraulic roller for your application?

- Allen.

I want to run it hard.
I want to drive it home
I want to build in the spirit of the 289
I am inspired by the original blueprint

I toasted a 351 Hyd a couple of weeks ago and never got it to the track. I want to move power a little higher and try to carry momentum. How high can you safely rev a hyd.

I have know idea what was in mine. It was weak.

Gotcha...just wondering...

I think 6500 is about the conventional max for a Hyd valvetrain. Wouldn't want to sustain that speed though, but your bottom end is pretty stout.. I just have a normal 2-bolt main 302 block, Scat Crank and 347 stroker kit so I'm running a CompCams Hyd grind for the 302hypo firing order rather than the 289 firing order....supposed to be more balanced. Heads are Dart Pro1 170s...I have IDA's on mine.

- Allen.

Your firing order is interesting - thanks

What specs did you use on your Cam? How high do you spin the 347?

Can you share some numbers -

What is the maximum duration you would run with 48's?

What do you consider as the maximum separation (split) for duration?

x-chr

Call Jim Inglese. He is the best one to advise you. Ask and then follow his advice! He is truly the master. I speak from experience. You can find him here:

Home

I already purchased the 48's. I did not purchase from Jim. I am not comfortable asking him for tech since I did not purchase from him. I have read all he has on his site.

I'm interested in guy's that have built and run them (SB with 48). I have searched for the original 289 specs out of interest, but have not been able to find them.

chr

This sounds like it will be a great engine.
Some will smile when I ask this question ;) ....what final drive gearing are you going to use?
Cheers,
Glen

Yep, that's the best approach.

You're going to want a mix of the two cams that you listed. The 222/224 cam won't get you to 7000, but I would consider it more correct on the duration split. The 242/248 cam has a bit more duration than you need, and I think it would have too much overlap for the Webers. The LSA is correct for both cams, 112-114 is usually the sweet spot.

Lift should match the capability of the cylinder heads.

Comp has a myriad of solid roller or solid flat tappet lobes to get you anywhere you want to be.

My hyd roller cam is a CompCams 35-518-8

Specs are .555 - .565 224, 232 and 112 Lobe Separation

I've been known to use the entire 6500rpm...don't spend a lot of time up there, but the webers take it up there quickly.

Have fun!

- Allen.

Sorry, just saw this...

If you want to make peak power at 7000, it's a little different than being able to pull to 7000. What are your exact goals?

For a split, I would consider 2-4 degrees optimal.

AFAIK, the specs you want don't exist in an off the shelf solid roller cam. I'v searched, and haven't been able to find one from any manufacturer.

The wide LSA is important for Webers, or any IR intake system. That keeps overlap to a minimum. Since you don't have a common plenum, the overlap will create the fuel cloud from reversion.

I rtan a cam similar to this one (hydraulic roller) in my 427W. It makes great power, and pulls like a freight train all the way to red line. It makes power pretty much everywhere.

Use caution with your head selection. I'm using some Dart Pro-1 195 heads. They have a 2.02" intake valve. A couple of years ago I tried a set of Brodix heads, with 2.08" valves. I lost all my low end torque. The intake was too big for the throttle body, and the intake charge lost it's velocity. The intake valve should not be larger than your carb/TB bore.

Your carb bores are 48mm. Your intake valves are 50mm. You might have a mis-match there. The blades and other stuff do take up some space, so you might be OK. If you haven't purchased your heads yet, you might reconsider that choice.

7000 is a marker for strength, but I would like to be able to safely pull perhaps 6300 (6400 would be very happy). I looked at mean piston speed data and I was around 3500 at 6400 where 4000 was the max for a performance engine (not race). I want to build something strong - it is rather expensive for me, so it needs to last some. 7000 is a valve train goal. We will limit it once we see the dyno.

Here is some data on the 289. 301 @ 5900

Hi-Po 289 Shelby 289 Gains
RPM HP TQ HP TQ HP TQ
2600 121 245 132 266 11 21
2900 136 246 147 267 9 21
3200 159 261 174 285 15 24
3500 185 277 198 297 13 20
3800 207 286 221 306 14 20
4100 224 287 240 307 16 20
4400 240 286 259 309 19 23
4700 253 283 277 309 24 26
5000 262 275 287 301 25 26
5300 269 267 296 293 27 26
5600 272 255 300 281 28 26
5900 273 243 301 268 28 25


My understanding is Shelby Factory cars made as high as 380 hp. How high were they turning those? I assume they were using most of it. We know they were were capable of 150.

My car is running 3.54 JAG. I am concerned with the 3550 strength, but I'll fix it when I get there.

100 @ 4500

133.6 mph @ 6000
135.9 mph @ 6100
138.1 mph @ 6200
140.3 mph @ 6300
142.5 mph @ 6400
144.8 mph @ 6500

4th - plenty for me - Can only imagine what it is going to feel like. :) I plan to use aluminum fly wheel. I want it to rev quickly, throttle match easily, and feel very connected to the steering and suspension. I have not run the lower gearbox ratios.

It occurs to me Shelby had to engineer around the Webers and Cam?

The 5.0 Mustang drag race guys have been spinning their engines to 7000 rpms for years using the stock factory hydraulic roller lifters from Ford with little to no problems.....
You can get 6500 rpms out of a hydraulic roller set-up easily....You will not be staying at 7000 rpms very long, most likely once you hit that number, you'll be shifting...
I wouldn't hesitate to go with a hydraulic roller set-up instead of a solid cam set-up for your intended use....
Little to no maintence and easier on parts, also larger selections of cams to pick from.......

Just my 2 cents on the subject.....

David

For a 6500 peak on a solid roller for your application, I would use the Comp Cams Xtreme Energy lobes. They are aggressive enough for power, but not aggressive enough to cause valvetrain issues.

How efficient the cam is depends on how well the heads flow, so with a decent head, I would go with something like a 230/234 @ .050", 112 LSA, .561/.561" with a 1.7 RR.

Those lobes work really well but aren't spring eaters or valvetrain breakers.

I would personally rethink the Eagle bottom end and use the Scat crank and rods. Mahle makes a really light piston for this application that's already coated and has a thinner ring pack. Good stuff.

An aluminum flywheel works well with the road race applications, but keep in mind that an aluminum flywheel will make a high strung engine a little harder to drive on the street, and the result is having to slip the clutch more to get the car going.

Wow - thank you for reminding me of this. I read this and did not apply - I will. Exactly the reason I am here. My builder does not know Webers - the Cam specs freaked him out.

If it is to be - it is up to me.

I appreciate your input.

chr

I hear you loud and clear - I am committed to solid.

x-chr