First, always easy to armchair, and we aren't writing your checks LOL. Always need to remember that these are the days...when could you bolt together mostly off the shelf parts for 650 HP in an FE. It's a cool engine and I am not throwing stones in any way
However, I would like to clarify a couple after your response
1 - My comments are only to throw out ideas because you mentioned you would have liked to see 700 HP, nothing else
2 - I have never seen 660s not make HP over 1850s, even on smaller engines So my thought goes to two things, either bad 660s, or the ignition. Not a curve issue, but maybe a bit of a ignition problem that wouldn't let more cyl fill do it's thing. Just a thought, too bad the 750s couldn't make it on their, I think it would have liked it. Something to look at would be a close look at the curve/numbers to see if it was getting funky up top. Could even be a valve bounce or float that is acting like a governor. Just a thought without seeing the sheets
3 - The cam discussion wouldn't have revved it higher (unless you wanted that). TFS behave differently than other heads. The intake port is real good for it's size. However, a second part of it being good is it's small and reacts quickly, it doesn't need or want a ton of overlap to pull it along using the exhaust pulse. So you can spread the centers and they are happier (wider LSA) . The exhaust on an TFS though is good, but not as good as the intake, so they tend to like more duration to empty the cylinder. So lets say you used the exhaust same intake lobe, but more exhaust lobe and spread them, you'd likely make more power everywhere, not really an RPM increase.
Would those changes reach 700 hp? I think so but, it really depends on the intake too, it may need some rubbing. However, I am not a tunnel ram guy, but I do like playing with runner length math and what you are seeing makes sense...more torque for a given flow. That being said, I think there is more in that bad boy
Again, no negatives, as I said, when you can run gallons of fuel through the dyno, not break and then go racing with over 650 HP, that's a good one. Just bench racing based on your 700 HP comment
Ross, we're good. It's all good discussion material. I still cringed every pull, but it all ended well. Heck we tend to put a bunch of pulls on them. Can't recall if it was the original 496 or the previous build that we put 34 pulls on it!! Then raced it carefree. Good builder, good parts and some good luck thrown in.
I've had the dream of putting a TR on the car for a few years. Jay made it possible. After reading his book and the slight chance of an increase in power added to the "want to buy" thought.
When it all fell together this winter I went for it. Here it is, dynoed, and are my dreams fulfilled? Ya, mostly. Did I want to see a 20+ HP increase? Sure. Did I see it? Sorta, only through the middle but not like I imagined it. Jays book was WRONG!!!!!...........................LOL!!! ( Sorry, just had to throw that out there. No blame at anyone!!).
I thought the motor made 675 before, but it was 665, so it was going to take 30+ to get that 700 mark. My mistake(should have dug out the dyno sheet sooner). Like I mentioned Jay's motor did crack the 700 mark and was "sorta similar" to what I have. He did run 660's and then 860 center squirters and I think the big ones topped the 700 but he said it was kinda ratty down low. So, that is where my dream of 700 came from. I know it was a stretch. When the peak was down I was really bummed, but after looking at the curve and seeing the substantial increases I was a bit more relieved after throwing all this money and time at it.
I too would have assumed the 660s would make an improvement. Maybe they could have if we spent more time on them. There again, we were kinda limited due to scheduling and I went into with that in mind and it was well known to everyone. Run any carbs I can get rounded up, but then time became an issue and if we wanted to get it done with the 8 gals of fuel, we had to narrow our field of vision. My nasty old 1850s have served me well for decades, so I choose to stick with them.
As for power curve, there was a little dippty doo after it peaked. With adjustments we gotten it to flatten out, but not raise overall power. Was not an issue with tunnelwedge using same distributor and shops MSD box. Not saying it couldn't be ignition, but the parts used had no issues previously.
Cam: Like mentioned, this motor was not built to run the TR. Improvements can be found, someday.
People are often shocked when I tell them they need to go smaller on the camshaft but a lot of guys over-cam with modern heads. I bet the overlap on that cam with the .050" durations being as high as they are, coupled with a 107 lobe center, is probably at 100° or more.
If you decide you want to tinker at the end of this season, get in touch with me. Catch me in a good mood and I may even float you a cam to try....
Something to think about. Thank you for the offer. Time will tell this year.
My only hope(to save money LOL) is I could reuse my existing springs if they are up to the task. If not, I guess at that time the heads would have to come off and I would then port the adapter to the heads and the TR to the adapter.
Not sure if a lot of people on here watch the engine masters program, I subscribe to the Motor Trend deal just so I can see those episodes. They have a recent episode where Frieburger puts a tunnel ram on his big block chevy for aesthetic purposes. The results were almost exactly as you describe above. Fatter torque curve and power down low, loss of power at the very peak. Might be interesting for you to watch if you haven't seen it yet.
The crusher camaro? I think I saw that? I've watch a lot of those Engine master videos(though not a member). Always very good, solid information, not BS or sales pitches.
The thing is, at least from what I remember growing up, a TR was all about high rpm power. It seems backwards to see it make power down low. But remember the Mopar cross ram with 3 ft long runners in a regular car. So going by that, you would know that it was not really a high rpm intake. More about torque.