Sorry for any confusion; yes, my rocker ratio tests were pre-Victor heads. Thx

No gains at the track, but there were some gains on the dyno as I recall? 5-10hp??

It was with my old ported '452' OEM heads, where I went from 1.5s I&E to 1.6s I&E and saw zip / nada / zilch show up at the track. I was really expecting some improvement, but... nope. It's not apples to apples, but it's at least one experience where more ratio got me nuttin'.

Intake-only 1.6s did show something like 5 HP w/ the Stage VIs on the dyno, but I ended up sticking with 1.5s on both I&E once the engine went into the car. The 1.5s went with the Stage VIs when they were sold.

When buying new rockers for the Victors, I went w/ 1.6s to go along with the switch to a solid roller. Fully loaded against a "real" spring they're 1.54-1.55 with a net (after lash) lift of ~ .650" w/ the RX roller.

Which brand rockers Brad? Got to say Dwayne is real close or spot on with the clearances he listed with retarding my cam per degrees. I over shot the 106 install degree and landed on 108. At 108 I measured .054 and .065 on intake and exhaust with .020 lash in each. I still have a 1.6/1.5 rocker combo. My math tells me it will be very close on both valves at 106. I’m sure it will take the 1.5 on the intake to get to an acceptable clearance. Hope to get more time this weekend.

I've used a number of different rocker brands and types. IIRC, the all 1.5s vs all 1.6s test used Rocker Arm Specialists 1.5 stainless-steel rollers and Crane "Gold" 1.6 aluminum.

The Stage VIs used Hughes (formerly Probe Industries) standard-offset 1.5 and 1.6 rockers.

The Victors have Hughes Victor-specific intake & standard exhaust 1.6 rockers.

The only ones I have pics of are the rockers on the Victors. The exhausts are their current "channeled" standard-offset style, while the intakes are their earlier "full body" .600"-offset style.

Ok, thanks for posting.

I wonder why you are having clearance issues? I run a lot more lift and don't have any clearance issues. 268@.050 exhaust is 27x @.050. .465 lobe with 1.6 rockers. With the victor heads you will want to run as much lift as possible.Have you considered cutting the valve reliefs deeper? https://www.lindytools.com/ihpc

On 440 -1 heads. They start life at 75cc?, Max stated cut is down to 62cc. But as Dwayne pointed out to me, work on the heads can alter how much would have to come off to get to 62cc. In my case it ended up being too much for high (15/1) compression, and i had to have a head welded and fixed. Now i have what i consider to be the ultimate set of moderate compression heads! Someday maybe on a BIG pumpgas street motor😁
So if you plan on buying new 440-1 heads, mike the deck thickness, and only cut them half of what it would take to get to 62cc. I think that would be . 040. Now you have a set of heads that can survive refinishing the decks more than once. At a multiple of cuts totaling . 080, they might not like super high compression or heavy doses of nitrous.

I would have to check my notes, but I thought I had .035 cut from the head and I used a .042 head gasket in place of the old .052. I use icon pistons. Evidently they don’t have deep notches. Something else odd I found while decreeing cam, when I installed straight up, dot to dot, the exhaust valve ran right into the piston. It did not do that at any other point , A4, A2 or R4.

You need deeper valve reliefs.You may be lift limited regardless of cylinder head choice.What is your current combo? Weight, gear, cubic inch, converter, et, mph etc. I know you and others have not been happy with the Victor heads. My father in law and I have had the opposite. His has been an over achiever from day 1.

Just checked my notes and i had .045 taken off heads. Chambers are now 67cc. Icon pistons have a 12cc dish. Its a 511 with 12.5:1 static. Heads are cnc ported with an intake port size of 330cc. They flow 278@.400 and 356@.700 intake and 203@.400 and 254@.700 exhaust. 2" headers with 3.5 short exhaust. 727/8" 5400 flash, foot brake, 4.10/28" tire 3480# race weight. I currently run a Indy T ram, but previously ran a 1100 Dominator which ran a best at that time of 10.06@134.

Just found the piston specs. Valve notches are .215/2.30 intake and .199/1.88 on exhaust. Pistons have .002 positive deck.

Just my thinking on the subject. Look at the total flow sheet find out where the max flow is then use a lift of .050 more.

And if your not going to do that, then an extra .030 or .040 lift from a 1.6 I don't think amounts to anything at the track.

And max lift has nothing to do with p/v clearance. They are closest at opening/closing points Valve timing (duration/centerlining) is the key player here. I am also surprised you are having this much trouble with 269 degrees.

I have been using a 1.6 on the intake only. I now do not have the clearance, so a 1.5 is in order, but was curious to any real performance loss doing that. Head max flow is at .700. With a 1.6 rocker my true lift with 1243 springs and lashed .020 is .665 and with a 1.5 will be .625.

I would love to see what would happen if you put an Isky RR735 rollercam in it. The cam is 278/288/110 . Intake lift is . 735 with a 1.5 rocker, lash was(?) .026 . .200 diration was close to 200 on intake, but it needs good valve springs. Not sure how much overkill i had, but i used Comp 947 tripples at 330 on the seat. Up the compression somehow to as much as you can run, and mid nines at 3500 lbs could happen. That cam was making 800 hp by 5700 rpm in a 4.5 bore 528 at 13.5 compression and peaked at 847 at 6900. I was using 1.55 Jesel rockers and . 043 rings, which from what i understand make a difference . But i like the power curve on that cam. It didn't seem to want more converter than about 5200 to 5600.

There wouldn’t be enough clearance for that cam. My old flat tappet 270/276-110 had .118 on the intake and .140 I think on the exhaust. I am a bit surprised this mild roller swallowed up all the clearances. That solid flat tappet was installed at 105.5.

Was that .118/.140 figure measured before or after the heads were milled.045”?

Your old SFT lobe vs a moderately fast SR lobe of the same duration @.050”.......... the SR would only have about .015” more lobe lift at TDC with both installed at 106.

With the new cam installed at 106, what is the lobe lift at TDC?

The roller lobe I was using for comparison would be .154”

Here’s a dumb question.........
You’re not trying to degree the new cam and check for clearances with a flat faced lifter, are you?

The .118 measure was after decking the heads and using a .042 gasket. My lobe lift is .430 giving me .665 with .020 lash on a 1.6 rocker at max open. Yes I am using roller lifters for measuring. I still have not ordered new pushrods yet, so I have been using the old flat tappet pushrods to measure. They are 9” long, too long as I have the adjusters almost all the way out to fit for measuring. Does this upset the measure at all?