Both cams are on the 106, trying to fool engine into thinking it has more compression than it does at 10.12:1, and 3000ft elevation. It is a pair of 1905 AVS 2 650's. Also have a pair of 1902 primary boosters coming to reduce the volume if this proves to be too much. I know some guys cringe at these carbs for tunnel rams, but I will try.
Ordered a new cam today for the W2 408
- Thread starter cpearce
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RAMM
Well-Known Member
Longer runners lower torque peak--just look at the cross ram stuff which is a tunnel ram laying down. The CSA and cylinder head characteristics dictate RPM first, camshaft/valvetrain second. That being said--W2 heads are very RPM capable-you will have no trouble. No comment on the cam I'll leave that to the cam grinder. J.Rob
Thanks, the tunnel ram is new turf for me. As for the cam, I respect your discretion.
512Stroker
We are all here because we are not all there.
If you like the hyd cam you have now and all you want is more rpm, just swap out the hyd rollers for a set of solid rollers.
The pushrod length will be longer and you may want a heavier spring.
The Holley Tunnel Ram doesn’t really have very long runners. Can you measure them & vs what you were running? I only have the MP Tunnel Ram version I can measure.
ValiantRacing
Well-Known Member
Chris at Bullet is very good at coming up with a cam for all different kinds of combos, he is the only one i talk to at Bullet, and that is all we use for cam grinders anymore.
Bakerlite
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Careful there, from what I understand, not all HYD profiles will take a solid roller.
And I'm going flat tappet to simplify things, not further complicate. I've seen the results of a roller lifter failure.
512Stroker
We are all here because we are not all there.
You do need to be curious
The cam manufacture can tell you if the cam profile is compatible, in my case it was, it's all about ramp speeds. Many members have done this successfully, Yellow Rose was the one who got me going on it.
Made one small spec change today, LSA from 106 to 108. This was done for the fact it is a 4 speed with a light flywheel, this and fine tuning should help dampen the pulses at low rpm in 1st gear. With the current cam, it occasionally started to buck in parking lots, requiring the feathering of clutch.
Tight 108-106, etc…. will do that. That’s why the after market makes cams at the 110 for automatic and manual cars alike.
That is good news, I was getting a little bit at very slow speeds with 3.23 and 3.09 first. I thought my flywheel was 18lbs by memory, but it has been a while since I looked, could be 20. Might also be the 23 degrees initial timing. Also changing to 3.73 gears.
Could be 18#s... Iam running 16 initial then it ramps up at 1200 rpm . I have a digital advance curve . Could be that .
A few things can cause bucking/surging. Too much timing, lean mixture.
Widening the LSA is the wrong way to reduce overlap; you reduce duration & keep the correct LSA.
D. Vizard has a veeeeeeeeeeeeery good you tube on this titled Fords 303 cams; sorry, do not know to link it, maybe somebody can.
Widening the LSA is the wrong way to reduce overlap; you reduce duration & keep the correct LSA.
D. Vizard has a veeeeeeeeeeeeery good you tube on this titled Fords 303 cams; sorry, do not know to link it, maybe somebody can.
Phreakish
Well-Known Member
TT5.9mag
Two atmospheres are better than one
I have no dog In the fight, but imo that’s another Vizard video that is hard to watch. He states what he is saying is fact, and it may be, but provides zero actual data to back up the claim. Show us some freakin numbers to back your claim.
I think David may be in early stages of dimensia. He seems to have a hard time completing thoughts .
It’s an issue from last brain surgeries
TT5.9mag
Two atmospheres are better than one
That’s very sad to hear. Hopefully it is not the case. Although I would like him to show maybe a dyno graph or two of back to back A to B comparison testing like Richard Holdener does. It puts credence to the claim.
K.O. SWINGER
Meeting in the alley since 1976
To me bucking would seem more of a gear ratio/converter problem then lobe separation angle thing.
The choppy idle of the 108-106-etc and not enough gas is the issue. Same as a stock engine would do but more violent and cranky. It just takes a hot minute to figure out and forget about it.
K.O. SWINGER
Meeting in the alley since 1976
Yeah somewhat but too tall of gear with a hi duration camshaft will also be a cranky setup equals bucking
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