cam specs for 406, thoughts?

[samadhi]

rhs 200cc heads
750 double pumper on air gap rpm intake


Spec card
part #: 35-000-8 engine: Ford 351 windsor
grinding instructions 1
"" "" 2
"" "" 3
grind #: Fw 3017f /3038f hr112.0
spc inst 1:
Spc inst 2:
J. Diam: Std int exh
valve adjustment hyd hyd
gross valve lift .580 .577
duration @ .006
tappet lift 286 294
valve timing open close
@ .050 int 10 46
exh 57 5
specs for cam inst. @ 108.0 centerline
int exh
duration @ .050 236.00 242.00
lobe lift .363 .361
lobe separation 112.0 firing order std
rocker arm ratio 1.60 1.60 req

[Gordon Levy]

It will run good but it will be a little soft at the bottom. You neally need to port that intake to the heads or use a Victor Jr intake. The heads will out flow the unported RPM air gap intake. You may also want to think about a 650 carb instead of a 750. The 650 will have better drivavility than the 750 but the 750 will more more top end power.

[samadhi]

Hey Gord, thanks for the response.

I plan or porting the intake, the gasket set I got is going to require porting on both the head and intake side. The heads have had some port work done on them, just gasket matching left.

Maybe I will look at a 650, should I stay with a dp?

I am most interested in driveability.

How soft are we talking?

[Bob Cowan]

Should make good power in the lupper to mid range, and even some pretty decent power in the bottom end. Remember that a stroker makes a big cam seem "smaller", so it won't be as bad as you think.

Not sure about the intake, though. I'm thinking the manifold and carb might be a smidgen on the small side.

The if you have the heads set up for a hydraulic roller, you should be fine. But if it's set up for a flat tappet, then you valve lift is right at the edge of acceptable. I would disassemble the heads completely, and check every spring with a micrometer.

If you have 58cc combustion chambers, be sure and calculate the dynamic compression very carefully. The intake valve closes sorta early, which is good. Good pressure makes good power. But you don't want too much pressure.

[Gordon Levy]

If you already have the 750 then use it.

[samadhi]

no 750 yet, so it's an option.

I've told my engine builder your opinion and he now thinks that comps recommendation is a bit big.

I suppose he'll call again tomorrow.

Any good/bad choices you guys have tried?

Thanks!

[Gordon Levy]

That's smaller than most of the cams I use.

[samadhi]

The above cam vs the xe282hr so many seem to be using?

I want a choppy idle and smooth driving off the line.

I saw a tv show, muscle cars maybe, where they compared an air gap to a Vic jr and the difference was 2hp or less all the way.

Should I look at a 650 dp?

If like to only buy these engine parts once.

Thanks for the input.

[Gordon Levy]

You will like that cam you posted. The 750 carb will be fine. The flow bench number between the RPM and Jr are very different. I would be surprised that unported versions would be close to the victor jr.

[samadhi]

Thanks Gordon.

The ports on the intake and heads seem to be very close in size. To be honest I'll have to port both to match the gasket but they practically line right up.

Being a rookie I may be missing something, I'm likely missing lots!

Cheers!
Vic

[Gordon Levy]

They really aren't. The unported RPM matches a Felpro 1250 and the Victor Jr matches a 1262.

[samadhi]

My engine builder obviously ordered the wrong gasket, it's much larger than the rhs port although the packaging does say sbf ford rhs heads.

Heads intake measures 1 3/16 x 1 15/16
intake measures 1 1/16 x 1 5/8

heads are an 1/8 bigger all the way around so I stand corrected.

I'll port them and order a new set of gaskets, so a felpro 1250?


another $50 down the drain.

So to review:
original cam okay
stay with the 750 double pumper
port intake
purchase new gaskets.

The new canadian 50 dollar bills have a clear plastic section. Really hard to flush down the toilet I bet, thank god for this project or I wouldn't know what to do with my money!

[Gordon Levy]

There is a steel core version of the felpro 1262 that would work well for your engine.

[samadhi]

The 1250 no?

I looked at the gasket that my builder purchased and its slightly larger than the 1262, good thing I hadn't port matched it yet. I thought that was going to be a lot of aluminum on the floor.

[Gordon Levy]

He could have got a 1262R which is the intake gaskets used for most of the 225 cnc heads out there.

[samadhi]

Okay.

So that gasket in bigger than the ports on both the intake and heads, I port match both the heads and intake to match the gasket, yes?

That's what I think I'm supposed to do.

The gasket my builder purchased is a Flatout gasket 8011, its 1.29 x 2.12

I wonder if I need to put it in the toilet also.

[samadhi]

One more question: which of those 2 cams we've talked about is 'bigger'?

Thanks
Vic

[Gordon Levy]

The 282 is bigger. The profile you listed is going to make some good power.

[samadhi]

Its almost funny that I know so little, I assumed the opposite.

Which would you choose for a rough idle, street able car?

[Gordon Levy]

Both will have very aggressive idles and will be streetable but they will be happier at higher revs. I don't think you will be disappointed.