Is this to much flow for a 346?

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Dec 23, 2002 | 12:54 AM

Jev3520

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Is this to much flow for a 346?

Heads were flowed on a SF 600 @28" h2o w/ 2.055/1.60 Ferra valves. Heads flow: Int .200-127 .300-190 .400-241 .500-277 .550-289 .600-296 Exh. .200-99 .300-143 .400-176 .500-201 .550-209 .600-215...
and r the valves to big for a 346???

Dec 23, 2002 | 06:40 AM

10secondZ

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From: Lake mary, (Orlando) FL

Re: Is this to much flow for a 346?

the valve's are fine and the flow is perfect..just make sure you have a sufficiant cam and those heads should be milled .030 if they are not already milled...then yes you will be just fine with a 346 <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

Dec 23, 2002 | 10:28 AM

1CAMWNDR

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Re: Is this to much flow for a 346?

There is no such thing as too much head flow. Just not enough cam/motor to use the head. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
I believe that was a quote from SAM instructor Jud Massingale. <img border="0" alt="[Driving]" title="" src="graemlins/gr_driving3.gif" />

Dec 23, 2002 | 03:35 PM

Fenris Ulf

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Re: Is this to much flow for a 346?

Your low and midlift numbers are a little weak, and no there is no such thing as heads that flow too well <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

Dec 23, 2002 | 07:57 PM

Brian Tooley Racing

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From: Bardstown, KY

Re: Is this to much flow for a 346?

Has anyone had idle issues that had heads with 2.055 and 1.60 valves? We have had customers that went to smaller valve heads and fixed their idle problems. Maybe I'll start a thread on it.

Brian

Dec 23, 2002 | 09:56 PM

99 Black Bird T/A

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Re: Is this to much flow for a 346?

<blockquote>quote:<hr />Originally posted by Jev3520:
Heads were flowed on a SF 600 @28" h2o w/ 2.055/1.60 Ferra valves. Heads flow: Int .200-127 .300-190 .400-241 .500-277 .550-289 .600-296 Exh. .200-99 .300-143 .400-176 .500-201 .550-209 .600-215...
and r the valves to big for a 346???<hr /></blockquote>Personally, I think the flow numbers are a little low for using 2.055 valves. If you can get someone to look at them that knows LS1 heads, you might be able to tweak a little more out of them. Remember the valve job is just as (or more) important than the port work. My guess is, like Fennis suggested, is the mid range could be improved.

Dec 24, 2002 | 12:21 AM

John B

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From: Phoenix, AZ

Re: Is this to much flow for a 346?

<blockquote>quote:<hr /> Has anyone had idle issues that had heads with 2.055 and 1.60 valves? <hr /></blockquote>I have the MTI S2 heads with these valves and with my B1 cam (221°/221°, 0.559"/0.559", 114°) it purrs like a kitten whether cold or warm <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

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Dec 24, 2002 | 09:28 PM

Jason99T/A

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Re: Is this to much flow for a 346?

<blockquote>quote:<hr />Originally posted by HITMANSS:
You can't measure velocity on a flow bench. <hr /></blockquote>Actually, you can. As long as your flowbench is equipped with a velocity probe. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> Pretty neat little tool. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

Dec 25, 2002 | 01:32 AM

#10

Fenris Ulf

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Re: Is this to much flow for a 346?

<blockquote>quote:<hr />Originally posted by HITMANSS:
For all those who are saying there is no such thing as heads that flow too well, you are dead wrong. I can't tell you how many times I've seen this happen --- the flow #'s are great but the real-world performance sucks.

You can't measure velocity on a flow bench. If your ports are too large for your combo, the flow numbers will look great, but TQ and throttle response will be poor.<hr /></blockquote>Most heads like the ones you described are either hogged out or have trouble keeping a uniform cross-sectional velocity. The tell-tale signs of this or often overlooked by those preoccupied with flow numbers at lifts their cams will never reach <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

Dec 27, 2002 | 02:20 AM

#11

2000RATA

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From: KS

Re: Is this to much flow for a 346?

Those numbers are a little weak especially for the larger valves thar were used. I'm getting much better numbers with 2.02's and 1.57's.

Dec 27, 2002 | 08:24 AM

#12

HITMANSS

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Re: Is this to much flow for a 346?

<blockquote>quote:<hr />Originally posted by Jason99T/A:
 <blockquote>quote:<hr />Originally posted by HITMANSS:
You can't measure velocity on a flow bench. <hr /></blockquote>Actually, you can. As long as your flowbench is equipped with a velocity probe. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> Pretty neat little tool. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> <hr /></blockquote>Didn't know that --- sounds neat. Never seen any published #'s though.

*****

I also think the flow #'s posted are a bit on the low side, especially below .500". Were these heads flowed w/ an LS6 intake attached? Was there a 6" pipe on the exhaust?

[ December 27, 2002, 09:14 AM: Message edited by: HITMANSS ]