[Dragncar]

We can discuss that here so it stays out of Pauls 455 HO build thread.

86azbird, I used to drive it to the track. Since I went to solid roller I just trailer it. Did not want to buy full 3" ex if I just race it. I have broken 3-4 9" rear ends and axles since so at this point its a pump gas strip car.

[tom s]

on the street 2000-2500.Tom

[grandam1979]

5500-6000

[slowbird]

6000-6200 with our 197 HO heads
5700-6000 with or 62 heads

[form74]

5500 to 5800 6X-4 Heads

[Scott Stoneburg]

474 with ported iron D port....6500.

[Steve C.]

1969 #16 d-ports
4.210" stroke
462 cid
TH400 / 4.33 / 28" tire / About 3790 lb race weight at the time

The last time it was on the track was in 2000 with those heads and that combo. At that time foot brake at about 1500 rpm. The converter would flash to about 4200 rpm and we used a 6200 rpm shift chip in the shift light for both shift points. By the time you factor in the human reaction time to the shift light and the transmission makes the actual shift the engines rpm is well into where it made its peak power which was at 6400 rpm for that specific combo. We tried other shift points but this seemed to work out good and we didn't beat the motor up too bad. The shift light came on just before we reach the traps and it would go thru the lights at about 6500 rpm, maybe a little higher.

1.51 60-ft.
10.79 ET
124.96 mph


.

[Half-Inch Stud]

Could shift 1-2 at 5200 for best ET,
2-3 seemed to want 5200 too, but not sensitive.

The 10" Converter being 2800-3200 made the shift point favor early for best ET

[Stan Weiss]

The only way asking where someone is shift at, makes any sense is if you also know what they are running for a camshaft.

Call up your camshaft guru. Ask about making peak HP @ 6800 RPM with 220 peak intake cfm @ 10:1 CR in your 455 and see what he says. If he does not lol then the camshaft specs he gives will scare you.

Stan

[Dragncar]

Originally Posted by Stan Weiss

The only way asking where someone is shift at, makes any sense is if you also know what they are running for a camshaft.

Call up your camshaft guru. Ask about making peak HP @ 6800 RPM with 220 peak intake cfm @ 10:1 CR in your 455 and see what he says. If he does not lol then the camshaft specs he gives will scare you.

Stan

Da+%m right.

[Dragncar]

To be fair one of the reasons I shift the old dog a bit early is well, its a old dog. Lots and lot and lots of runs. If I shift near 6 it ends up crossing the line well over 6500. If I shift about 5600-5800 it crosses the line around 6200.
If the tach spends too much time well past 6K I am gritting my teeth at the end. So far its been indestructible. Broke converters, T400s and 9" rears and billet axles. I am either going to ring and bearing it with a RAIVish hyd roller I have and make a street engine out of it with ex manifolds (79 TA) Or if the bores sonic check, hard block and see if it cleans up at .065. Doubtful then try .070 . Its .060 right now. 70 HO block and 197s.
I will inspect and post pics of what it looks like inside when I tear it down. But I want to keep it running right now so I can dial in the carb and check tranny functions after I pull down the T400 and check out clearances/seals and such. Have it all ready for the 461 High Port engine.

I think if I had good light pistons and rings to go with new valve springs it would like to be shifted @6100 as Brians 197 HO does.

Thanks for all the input on 455 shift points, keep em coming.

[steve25]

Looking for where to shift the motor without stating if the heads are ported and what Intake system is on the car along with what Cam is in the motor duration wise is a full on waste of time!

If your looking for shift points in regards to bottom end durability then that's a different story?

[Steve C.]

"Looking for where to shift the motor without stating if the heads are ported and what Intake system is on the car along with what Cam is in the motor duration wise is a full on waste of time!"

I thinking similar as I was typing my response above. But I did not want to clutter the post with engine details. As a simple example, the intake manifold I was going to mention it. Not that engine but as an example on another combo on the dyno we saw a 200 rpm difference in peak power rpm between a Performer RPM intake and a Victor intake, peak power at 5800 vs 6000 rpm. Others have seen even wider spreads.


.

[HWYSTR455]

When I was still rowing gears with a Muncie, I shifted when it stopped pulling. On the 455 solid roller, mild ported '70 64 heads, that was roughly in the 5900-6300 range. The 400s I had went a little further, in the 62-6500 range.

If you're breaking 9" rears, you need better housings, not repurposed car or truck housings. I broke a few too until I went to Moser 9" setups. Last housing and axle setup I got, with 'mods', was in the $1100 range shipped.

The 461 solid roller shifted around 67-7200, higher if there was loss of traction or if doing a top end run.

.

[ponyakr]

Back when I ran cast rod 455's, I set the rev limiter at 5500. Shifted at 5000, on a normal pass. But, if it slipped a little off the line, would shift at 5400.

Sometimes I would shift higher, even with a good launch, then "pop the chute", just before crossing the finish line, in order to avoid a breakout, & outsmart a particularly competitive opponent, or someone I knew dialed soft & always tried to get to the line 1st. Won lots of races that way.

Most of those engines had unported big valve heads, like 16, 48, & 62. Most had 041 clone cam & Rhoads lifters, TH400 trans, 3.55-3.73 gears, & stock 13" converter.

I know these engines had nowhere near as much power as those mentioned in this thread. But, they had enuff torque to break a PG, a TH350, the int sprag in two TH400's, a BOP rear end, and an 8.5 rear end. Never broke an axle. That was probably because of using the 13" converters.

[PAUL K]

My ported SD-455 heads liked to be shifted at 6700 rpm on both gears.

[torqhead]

I shift at 6200, but as others said your shift point should be based on power produced which is controlled by engine combo, (
(cam,compression,head,intake,exhaust,etc).

[PAUL K]

Originally Posted by torqhead

I shift at 6200, but as others said your shift point should be based on power produced which is controlled by engine combo, (
(cam,compression,head,intake,exhaust,etc).

True..... also gearing and converter

[Dragncar]

Originally Posted by HWYSTR455

When I was still rowing gears with a Muncie, I shifted when it stopped pulling. On the 455 solid roller, mild ported '70 64 heads, that was roughly in the 5900-6300 range. The 400s I had went a little further, in the 62-6500 range.

If you're breaking 9" rears, you need better housings, not repurposed car or truck housings. I broke a few too until I went to Moser 9" setups. Last housing and axle setup I got, with 'mods', was in the $1100 range shipped.

The 461 solid roller shifted around 67-7200, higher if there was loss of traction or if doing a top end run.

.

The rear is a 59 truck unit with a full back brace. Tubes are like 1/4" wall. Stiff as can be. I bent the tubes forward before I welded the back brace on. I broke several posi units with no brace. And the Mack Williams billet axles were broke after the brace was installed. I have went to Moser 40 spline axles axles, Moser aluminum housing with the big Pro gear set and yoke.
Its hung on Alston 32" ladder bars. 1.43-45 60 foots which is better then the ET MPH show.
The converter is a PTC 9" that will stall up around 5500 but I launch at 3600 RPM.
I never liked the look of the Fab 9 housings unless a full race car.

[Dragncar]

I guess the point is that very few 455s with iron heads can pull serious RPM. Vast majority are D ports. A nice set might get 270cfm. Bore in kinda small, valves are a bit shrouded. Accelerating a crankshaft that is heavy, big bearings though pinched together ex ports is a tall order especially when you have a hard time getting air in the other side . Piston speed is very high.
Its not like you have a 454 with fat bore and 4" stroke and big square port heads to deal with.
I believe that more than a few are shifting them too high. Thats not to say people who know what they are doing should not spin them up.
But you can put a bunch of money into a iron headed pump gas 455 and most are better off shifting them sooner than you might think.

I started off with a set of well ported 197 HO heads, ported Warrior intake and custom solid flat tappet. Put some unported 96s on with hyd flat tapped then put the solid back in. Then had the HOs ported more and solid roller. Engines, valve springs ect last a long time if they are done right and you don't spin them to the max every time out.