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Gt40p's and E303 cam

  • Thread starter Thread starter justhereforinfo
  • Start date Start date Sep 15, 2008
J

justhereforinfo

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#1
  • Sep 15, 2008
  • #1
Im about to install a set up GT40p heads. I'm currently running an E303 cam, I have no idea what heads are in the car, but their cast iron and suck, so im not sure of the valve train and wouldnt be supprised if the springs dont match the cams lift. (new car)

I believe the E cam has a .495 lift. If so, is that too much for the GT40p's springs?

I can get a set of 1.6 roller rockers, will that help? Or do I need new springs to run this combo?
 

cenok is family

15 Year Member
Jun 25, 2003
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Sep 15, 2008
#2
  • Sep 15, 2008
  • #2
E cam has .498 lift. if your heads are cast iron, they're probably just stock e7's. if you just pulled the heads from an explorer, they have either .450 or .500 lift springs, i can't remember. either way, i'd swap them out with a better set because you'll be running them to their max. factory stamped rockers are 1.6 as well, so it wouldn't change anything with your lift.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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Sep 15, 2008
#3
  • Sep 15, 2008
  • #3
I keep promoting this combo because I think it's a great budget combo

GT-40P's with TFS upgraded valve springs

TFS stage 1 cam
 
J

justhereforinfo

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#4
  • Sep 15, 2008
  • #4
Do you have a link?
 
J

justhereforinfo

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#5
  • Sep 15, 2008
  • #5
Like this?
VALVE SPRING UPGRADE KIT, SMALL BLOCK FORD WITH OE STYLE CAST IRON HEADS MUSTANG
 

TomCat

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Sep 16, 2008
#6
  • Sep 16, 2008
  • #6
Might as well check the heads you've got for any common casting marks, just to be sure. If they're the E7s, you'll love the switch to the Ps
Like people have said, grab the upgrade valve spring kit from TFS, better safe than sorry.
 

85_SS_302_Coupe

it sucks (I know) to be on the receiving end
15 Year Member
Nov 11, 2003
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Sep 16, 2008
#7
  • Sep 16, 2008
  • #7
Mustang5L5 said:
I keep promoting this combo because I think it's a great budget combo

GT-40P's with TFS upgraded valve springs

TFS stage 1 cam
Click to expand...


I think this is like the 3rd time i've come in and seconded this statement


I've heard that even the stock Explorer cam is "too much" for the stock springs.
 
J

justhereforinfo

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#8
  • Sep 16, 2008
  • #8
Everyone keeps saying "stock springs". Are the Gt40p springs the same as the stock E7's springs?

What kind of markings would I find on stock heads? Or how would I tell what these are?
 

85_SS_302_Coupe

it sucks (I know) to be on the receiving end
15 Year Member
Nov 11, 2003
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Sep 16, 2008
#9
  • Sep 16, 2008
  • #9
justhereforinfo said:
Everyone keeps saying "stock springs". Are the Gt40p springs the same as the stock E7's springs?

What kind of markings would I find on stock heads? Or how would I tell what these are?
Click to expand...


Well, even if they are the same (which i'm almost certain they're not) as E7's, you don't wanna run any kind of cam with decent lift on them anyways. The stock Mustang cam is .444 lift, and i'm willing to bet the stock valve springs are just addequite for that cam. The Explorer engines weren't put together for high RPM, they were built for torque to move the big slug around. The way i see it, people get valve float with aftermarket cams on stock Mustang springs, and you know the Explorer springs can't be any better.
 
J

justhereforinfo

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Jul 15, 2008
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#10
  • Sep 16, 2008
  • #10
Thanks guys, I'll go with this combo and let you know the results in a few weeks.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,216
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Sep 16, 2008
#11
  • Sep 16, 2008
  • #11
Here's the cam

ROLLER CAMSHAFT, TRACK HEAT - 5.0L/5.8L STAGE 1 MUSTANG


And you have already listed the springs which i beleive work onthe GT-40P. I know they work on E7's as i installed a set.


Gt-40P's, TFS Stake 1 cam, an intake manifold and 65mm TB and supporting mods is a nice little capable combo.

Remember you will need P-specific headers as well. The FMS headers are a great header to run
 

Mr. Rustypwnz

Advanced Member
Jun 1, 2005
1,761
63
69
indianapolis/ valdosta ga
Sep 17, 2008
#12
  • Sep 17, 2008
  • #12
Everyone keeps saying "stock springs". Are the Gt40p springs the same as the stock E7's springs?

What kind of markings would I find on stock heads? Or how would I tell what these are?
Click to expand...

no P heads max out around .450 lift, get either the tfs spring kit or the crane kit, they both kick ass..

ive had a p head/bcam/explorer intake combo and it ran very hard to say the least, 20mpg and would beat a stock ls1 with a good driver.. I think I had like under $500 in it..
awesome power for the money!!
 

Joe Jr.

Founding Member
Nov 16, 2001
207
5
19
Longmont area of Colorado
Sep 17, 2008
#13
  • Sep 17, 2008
  • #13
Good info. guys! I just bought some P's also, and have been contemplating the trick flow cam and springs. I have to work over the heads a little at least tho and the cobra manifold......i can hardly wait..
 
J

justhereforinfo

New Member
Jul 15, 2008
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Sep 17, 2008
#14
  • Sep 17, 2008
  • #14
Will these rockers work with my setup? Are they interchangeable?





Stock Gt40p's




I'll be using a TFS stage 1 cam(.510 lift), TFS spring upgrade (.542 max lift), these 1.6 rr's, and Gt40p heads. Along with all the other usual bolt ons and a 130ish wet shot. Sound good?
 

RYC CUKR

Founding Member
May 19, 2002
1,437
1
38
Orlando
Sep 18, 2008
#15
  • Sep 18, 2008
  • #15
I run a GT40p/TFS1/Track heat intake combo in my 93 along with a set of 4.10s. With a AOD with only a shift kit, meaning still running the stock converter, it runs 14.0s@100mph. Keep in mind this a a full weight AOD GT vert. About the heaviest fox body that you can get. Put a 100 shot on it and it goes 12.7s@109.

And I used the TFS spring kit for Ford iron heads.
 

5.0Torx

Active Member
Dec 30, 2007
252
3
29
Sep 18, 2008
#16
  • Sep 18, 2008
  • #16
im in pretty much the same boat. i bought an exploder motor from a JY for $350 and am just waiting for the cashflow and mustang-downtime to do the swap!

good luck, lemme know how it goes!
 
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