Chamge to Ti intakes and 50 degree seats?

[gregsdart]

I have a 549 cubic inch dodge running Indy 572-13 cnc385 heads, 15/1 compression on injected methanol. Intake valve lift is gross .868, .020 lash, and i checked deflection with race springs and see .030 loss of lift in running state. The motor made 982 hp at 7600 rpm.
My question is, with a head limited combo like this, what gains could be expected going from a 2.30 stainless valve to a Titanium valve, as well as possibly changing seat angles for further gains. I am guessing i could still retain the stainless exhaust since rpm will be kept below 7800 rpm max. Do i have to have different seats put in for the change?

[mt-engines]

Do a 2.350 intake 50 seat with the supported bowl work.

That thing runs pretty good from what I've seen.

[gregsdart]

Thanks. Initial test runs show the dyno was, if anything, conservative. So i am hoping someone can give me an idea of performance gains i may see from this possible upgrade. I am guessing just eight valves plus bowl work and seat prep may run $2000?

[Dave B]

I have a 549 cubic inch dodge running Indy 572-13 cnc385 heads, 15/1 compression on injected methanol. Intake valve lift is gross .868, .020 lash, and i checked deflection with race springs and see .030 loss of lift in running state. The motor made 982 hp at 7600 rpm.
My question is, with a head limited combo like this, what gains could be expected going from a 2.30 stainless valve to a Titanium valve, as well as possibly changing seat angles for further gains. I am guessing i could still retain the stainless exhaust since rpm will be kept below 7800 rpm max. Do i have to have different seats put in for the change?

If you dont raise the rpm ,i doubt you see anything.Allot of expense for little gain imo.

[Dave B]

i know several people that have done same thing and saw nothing. I would fix both valves and bump rpm up to 82-8300 .Bigger valve is no garuntee for gain if everything in intake tract not designed for it.

[mag2555]

With that rpm range of less then 8000 and if you are not running such yet you might want to look into conical springs.
You would benefit from many things + it’s said the lighter springs and far smaller retainer can come very close to equaling the weight reduction of a titanium valve.

[ClassAct]

I have a 549 cubic inch dodge running Indy 572-13 cnc385 heads, 15/1 compression on injected methanol. Intake valve lift is gross .868, .020 lash, and i checked deflection with race springs and see .030 loss of lift in running state. The motor made 982 hp at 7600 rpm.
My question is, with a head limited combo like this, what gains could be expected going from a 2.30 stainless valve to a Titanium valve, as well as possibly changing seat angles for further gains. I am guessing i could still retain the stainless exhaust since rpm will be kept below 7800 rpm max. Do i have to have different seats put in for the change?

If I were you, I’d switch to Ti valves, up the RPM and use a 55 degree seat.

[Dave B]

i would spend 2k on your car. You should be running 8.30s now with that kinda power. My brothers sbc car runs 8.30s at 2885 and it made 947 on dyno.

[Rick!]

Wallace calculators don’t support the stated 986hp, more like 920ish.
You’ll need around an extra 60hp to run low 8.40s or like Dave mentioned, an improved setup.
You state the RPM limit is 7800? What parts are limiting the rpm?
Do you have a non-hero timeslip you can post? How about the dyno sheet?
Running a single Ron’s toilet?
Tunnel ram or single plane intake? Tunnel ram is worth about 35-40hp on a big cube BBM.
Whose cam? Specs?
Torqueflite or PG? RPM drop at shift? Convertor stall?
660-1320 MPH gain?

[mt-engines]

Wallace calculators don’t support the stated 986hp, more like 920ish.
You’ll need around an extra 60hp to run low 8.40s or like Dave mentioned, an improved setup.
You state the RPM limit is 7800? What parts are limiting the rpm?
Do you have a non-hero timeslip you can post? How about the dyno sheet?
Running a single Ron’s toilet?
Tunnel ram or single plane intake? Tunnel ram is worth about 35-40hp on a big cube BBM.
Whose cam? Specs?
Torqueflite or PG? RPM drop at shift? Convertor stall?
660-1320 MPH gain?

The air up here isn't the greatest.. only in the spring or fall you might run close to the corrected number

[mt-engines]

With that rpm range of less then 8000 and if you are not running such yet you might want to look into conical springs.
You would benefit from many things + it’s said the lighter springs and far smaller retainer can come very close to equaling the weight reduction of a titanium valve.

NO!

[gregsdart]

The reason i believe it is putting out what it dynoed, is something i didn't mention. I use a Deadenbear CC1 box, and had a 2 second setting in a lockout circiut. So when it was supposed to shift at 7600 at 1.5 seconds, it was delayed for .5 seconds and the data logger shows .4 seconds on the rev limiter at 8,000 rpm, not pulling. Still, it ran 5.47 at 128.65 mph in the 1/8th, with a soft low rpm leave, 1.224 60 ft. So i am not worried. Not to mention the DA was over 2000 ft.
I only have an 8:50 cert as well .my guess is it will need to be shortshifted a fair amount. BIR in minnesota can be a stickler for rules.
Keeping rpm down is a choice, no real problems, all good parts and i would like them to last a bit.

[Dave B]

If it will go 8000 and not gain it sounds like you have a cork in your intake tract. Lighter valve or bigger valve will not fix that. What happens to port speed with bigger valve? i would check over what you have going from plenum on down. But again your power and et/ mph do not come close to matching! We run in midwest air also. 2000 ft is awesome air. Da is not our issue its the shitty wgs.

[Dave B]

With that rpm range of less then 8000 and if you are not running such yet you might want to look into conical springs.
You would benefit from many things + it’s said the lighter springs and far smaller retainer can come very close to equaling the weight reduction of a titanium valve.

NO!

Ya no "comical" springs. lmao...But i love coming to mn to run . St louis or kansas in summer / almost always 35-50 wgs worse

[Dave B]

And maybe im way off base here. I have never chamged to ti valves, i will look into that.