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-   -   2.19 intake in Speedmaster heads? (https://forums.maxperformanceinc.com/forums/showthread.php?t=855437)

Murf 12-23-2021 10:38 AM

2.19 intake in Speedmaster heads?
 
Merry Christmas everyone!

I ask about 2.19 intake valves in another thread but it was in a thread with a different title so I thought I’d ask again. By the way, thanks to Steve25 for the replies!

I have bare Speedmaster heads that I’m going to buy valves for after the holidays. I don’t have an engine plan set in stone. I do have the following parts.

Hyd roller 236 / 242 .600 lift on 122

Performer RPM, Torker II or a Speedmaster single plane that looks kinda like a worked over Street Dominator.

No short block stuff yet but thinking 470-490 cubes.

So, at what point does the larger valve help? Is there a downside to having the larger valve, if it’s not need for the rest of the combo?
I’m sorry my question is so vague. I’m just trying to understand at what level the bigger valve would be helpful.

Thanks
Murf

PAUL K 12-23-2021 10:44 AM

Merry Christmas!

Valve shrouding. If it's a factory block we like to use 2.11 to 2.15 intake valves. The bigger valve gives bigger flow numbers but we haven't found a performance increase on a standard E-head when used on a factory block.

pastry_chef 12-23-2021 10:56 AM

I can tell you concerning E-heads.. On a 4.185 bore, SD Dave insisted that 2.19 intake valve was better than 2.11

Skip Fix 12-23-2021 11:31 AM

4 Attachment(s)
Here is a picture of a 72CC E head with a 2.15 cardboard cutout and a Butler head gasket and another with a 2.12 Manley after a little clearancing. And a blue FelPro.

tom s 12-23-2021 11:40 AM

Is the Felpro more of a generic gasket to allow valve reliefs for early valve angle heads?Tom

Steve C. 12-23-2021 12:06 PM

What performance level are you seeking ?

Butler routinely uses a 2.11 valves on his Edelbrock 315 cfm heads.
And here Dave states a 2.11 or 2.19 option on his 315 cfm head, with his higher flowing 325 cfm head using the larger 2.19 valve.

http://www.sdperformance.com/listPro...?categoryID=25

Years ago I used 2.150 titanium valves in a set of Edelbrock heads that approached 330 cfm. This was a 4.165 bore on a factory block. The lighter valve only because it was for a 7000 rpm combo.


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Steve C. 12-23-2021 12:33 PM

Related....

"We found that moving the intake valve close to the bore centerline to reduce shrouding significantly improves high-lift airflow, while allowing for the use of even larger-diameter intake valves."

This involved in the Edelbrock High-Flow Victor-Series Cylinder Head For The Pontiac .

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Skip Fix 12-23-2021 01:58 PM

Tom I'm not sure on the Felpro how it fits the chamfers in the blocks. That is the 1016 gasket. 4.3 diameter .

Steve C. 12-23-2021 02:57 PM

Using custom pistons or off the shelf pistons ? What size valve reliefs ?

Note this comment:

"Same as our 325 CNC but with 2.11 valves for valve pocket clearance when needed"

https://butlerperformance.com/i-2445...tegory:1394343


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Murf 12-23-2021 04:10 PM

[QUOTE=Steve C.;6304837]What performance level are you seeking ?

Butler routinely uses a 2.11 valves on his Edelbrock 315 cfm heads.
And here Dave states a 2.11 or 2.19 option on his 315 cfm head, with his higher flowing 325 cfm head using the larger 2.19 valve.

http://www.sdperformance.com/listPro...?categoryID=25

Years ago I used 2.150 titanium valves in a set of Edelbrock heads that approached 330 cfm. This was a 4.165 bore on a factory block. The lighter valve only because it was for a 7000 rpm combo.


.[/QUOTE

Steve, I don’t really have a horsepower level in mind but plan on using that 236 / 242 cam I mentioned. I assume I would not see any advantage with that cam. I was just wondering if since I have to buy valves anyway, it would be a good idea in case I wanted to do something later on.

I hadn’t even given pistons a thought. Would they need to be different if a person was using what comes in a “generic” stroker kit?

Thanks!
Murf

Steve C. 12-23-2021 04:35 PM

"I assume I would not see any advantage with that cam"

I think most here would agree.

For interest, somewhat related since it's a similar cam:
http://www.sdperformance.com/newsStory.php?newsID=44

And the pistons...

"Would they need to be different if a person was using what comes in a “generic” stroker kit?"

I doubt it. But someone else can comment from experience, I use custom pistons.

And a fwiw, that Speedmaster single plane is in fact based off a worked over Holley Street Dominator intake. With proper port work and runner blending It can easily support 600 hp if desired.
Based on my experience with the Tomahawk intake ( same ), if ported it can can go as tall as a 2.300" port and leave about 0.125" above for gasket seal.


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steve25 12-23-2021 05:12 PM

My 2cents worth!
Unless your going to have a professional port your heads to make really good use of the 2.19” valve then I don’t see the point, especially since you can’t state a particular HP level your shooting for!

Look at it in these terms also, even when the RPM heads that have been cleaned up are fitted with a 2.15” valve and then have porting work done, they don’t start to show substantial flow gains until .550” lift, so another question that needs to now be asked is how much lift are you willing to run?

Also the more port volume above 215 CCs you put in the head, the more compression your going to need to not drop off torque numbers below 4000 rpm should that be a concern of yours!?

If you have a auto trans are you willing to run a converter that will flash to 4000 or 4200?

Jack P. 12-23-2021 05:14 PM

So what about the exhaust 1.66 valve these come with. Would the OP benefit from a 1.77 exhaust valve?

steve25 12-23-2021 05:19 PM

Depending on what his intake flow number end up being, then maybe he might need to do such!

A lot hinges on his compression ratio .

Skip Fix 12-23-2021 05:52 PM

FWIW my 500" IA motor has 2.11/1.66 valves in it and dynoed 695hp.

steve25 12-23-2021 06:33 PM

Skip, but what lift are you cranking on that?

Steve C. 12-23-2021 06:48 PM

Story time :)

About 20 years ago a local friend built his 'tractor motor' with a set of out-of-the box 87cc Edelbrock cylinder heads... with their huge no velocity port volume !

He did nothing to them except an inspection and clean up, then bolted them on. It used a 400 block with a 4.250 stroker kit, Performer RPM intake, 1-inch spacer and a Holley 750 vacuum secondary carburetor and headers.
He used a 236 degree hydraulic flat tappet cam, it had 0.542" valve lift with 1.6 rocker arms.

On the dyno it made 509 hp at 5200 rpm. Today that number is nothing to write home about !

But he had fun with it... at the time he had a beat up '73 Firebird with a TH400, stock converter and 3.08 gears. On his first outing ,with no hood on the car he drove it up to our local track and ran 12.36 at 113 mph.
No traction aids, and I don't remember the rear tires but he said 2's something 60-ft !


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steve25 12-23-2021 07:00 PM

So what’s your point with this when even if the 400 block still had its stock 4.120” bore that motor was/ is 453 cid?

If you want to get down to brass tacks here about what it seems your alluding to then here you ya folks go.
If your after the largest amount of high rpm hp your motor can produce then you want a intake port velocity between 300 and 350 FPS.

If you want a much wider power band ( especially with CIDs under 400 ) then you want a port air speed that’s much faster!

Skip Fix 12-23-2021 08:16 PM

1 Attachment(s)
0.660. Just saying adding a bigger valve might not be needed.

But my wife's little 5.3 Vortec has enough bottom end torque to pull a horse trailer easily with it's 199cc heads so must have some decent velocity! And has even smaller valves than the E head!

PAUL K 12-23-2021 08:36 PM

Quote:

Originally Posted by Jack P. (Post 6304919)
So what about the exhaust 1.66 valve these come with. Would the OP benefit from a 1.77 exhaust valve?

Doubtful


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