Which Heads Would You Use?

mustangsteve · 08-05-2007, 10:26 AM

I'am looking to upgrade the top end of my 347 and like to know what you guys would run.

Currently I'am useing FMS GT40 Heads and Upper and Lower GT40 as well. I have 1.6 Rocker Arms and Cam is a Eldgen Stage II, ( 112 degree center lobe,... 222 intake.... 232 Exhaust.... .514 Intake .534 Exhaust )...

I plan on useing this Cam, But not sure which heads to go with.....I'am looking at:
AFR 185's..... Trick-Flow R Series....

I know I would like to use the Box Style Intake offered by Trick Flow and may have to go with the Trick Flow Heads in order to use this Intake unless you can use with other heads. On Summit's website it tells you for use with the R Series Heads.

I'am not sure which heads are better and one may not be but I'am looking for the one that will work best with my combo.

Also have to say that this is not just a track car, more time on the road than the track.

QWKSNKE · 08-05-2007, 10:32 AM

Unless you are running aftermarket pistons that are 'cut' for TFS heads (valve positioning) , then you can't run them with that big of a cam. If that is the case then I would use AFR 185's.

1Quik85GT · 08-05-2007, 01:39 PM

Are you using cast Gt-40s..if so, and not ported i will buy them

CrazyInBlack · 08-05-2007, 02:30 PM

Quote:

Originally Posted by 1Quik85GT

Are you using cast Gt-40s..if so, and not ported i will buy them

crap you beat me to it

or if they are ported ill take'um

mustangsteve · 08-05-2007, 03:28 PM

Quote:

Originally Posted by QWKSNKE

Unless you are running aftermarket pistons that are 'cut' for TFS heads (valve positioning) , then you can't run them with that big of a cam. If that is the case then I would use AFR 185's.

Yes I'am useing Aftermarket Pistons... They are Forged Probe Pistons..Part Number 10668-030 and they have a deep dish..

mustangsteve · 08-05-2007, 03:31 PM

Quote:

Originally Posted by 1Quik85GT

Are you using cast Gt-40s..if so, and not ported i will buy them

They are Aluminum GT40's Part number M-6049-Y303....

CrazyInBlack · 08-05-2007, 03:33 PM

Quote:

Originally Posted by mustangsteve

They are Aluminum GT40's Part number M-6049-Y303....

I did not know they came in aluminum, are they aftermarket?

QWKSNKE · 08-05-2007, 04:50 PM

Quote:

Originally Posted by CrazyInBlack

I did not know they came in aluminum, are they aftermarket?

There are 3 different aluminum GT40 heads Spence. Y303's, X303's, and I think Z303's.

MustangSteve.. Do you recall how much dish you have on your pistons?

I personally would still choose the AFR's but if you feel confident that piston to valve would be ok, then the TFS heads would be good too. Just depends on what kinda of deal you can get either head for

coupe · 08-05-2007, 04:53 PM

Steve, I would honestly take a look at having the GT40's ported by someone who knows. It's not a bad head. Are there better? Yes. AFR is definitely better. But I would save the $1300 for some other things. I think with some cleanup, the GT40 heads can work okay for a street/strip 347.

And I believe the Trick Flow "R" heads are way more than you'll ever need. The box intake will work with any sbf head except yates-style.

You would do well on your 347 with a Holley Systemax or the Trick Flow R-series manifold like ItalianLX uses on his 418.

QWKSNKE · 08-05-2007, 08:36 PM

Quote:

Originally Posted by coupe

You would do well on your 347 with a Holley Systemax or the Trick Flow R-series manifold like ItalianLX uses on his 418.

I agree and would like to throw the Performer RPMII intake as an option too. If this is a street car, I don't think you would be with the "streetable power" loss that would occur with a box style intake

08-05-2007, 10:26 AM	#1
mustangsteve Member Join Date: Dec 2006 Location: McCalla, Alabama Posts: 30	Which Heads Would You Use? I'am looking to upgrade the top end of my 347 and like to know what you guys would run. Currently I'am useing FMS GT40 Heads and Upper and Lower GT40 as well. I have 1.6 Rocker Arms and Cam is a Eldgen Stage II, ( 112 degree center lobe,... 222 intake.... 232 Exhaust.... .514 Intake .534 Exhaust )... I plan on useing this Cam, But not sure which heads to go with.....I'am looking at: AFR 185's..... Trick-Flow R Series.... I know I would like to use the Box Style Intake offered by Trick Flow and may have to go with the Trick Flow Heads in order to use this Intake unless you can use with other heads. On Summit's website it tells you for use with the R Series Heads. I'am not sure which heads are better and one may not be but I'am looking for the one that will work best with my combo. Also have to say that this is not just a track car, more time on the road than the track.

08-05-2007, 10:32 AM	#2
QWKSNKE 3v's are slow Join Date: Dec 2004 Location: Here and There Posts: 17,152	Unless you are running aftermarket pistons that are 'cut' for TFS heads (valve positioning) , then you can't run them with that big of a cam. If that is the case then I would use AFR 185's. __________________ 2009 Porsche Carrera S 2008 ///AMG C63.. Eurocharge Tune. RIP 2019 AMG GLC43..wife's 03 F250 SD.. Edge Evo, AFE Stage 1 CAI 08 GT. JBA axle back, FRPP springs, FRPP swaybars.. daughter's 01 Cobra vert... wife's I need a new toy

08-05-2007, 04:53 PM	#9
coupe Super Moderator Join Date: Dec 2004 Posts: 6,313	Steve, I would honestly take a look at having the GT40's ported by someone who knows. It's not a bad head. Are there better? Yes. AFR is definitely better. But I would save the $1300 for some other things. I think with some cleanup, the GT40 heads can work okay for a street/strip 347. And I believe the Trick Flow "R" heads are way more than you'll ever need. The box intake will work with any sbf head except yates-style. You would do well on your 347 with a Holley Systemax or the Trick Flow R-series manifold like ItalianLX uses on his 418. __________________ " If you can't explain it simply, you don't understand it well enough. " - Albert Einstein

08-05-2007, 01:39 PM	#3
1Quik85GT Senior Member Join Date: Apr 2005 Posts: 895	Are you using cast Gt-40s..if so, and not ported i will buy them