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Engine E7 Valve Spring Upgrade Suggestions.

  • Thread starter Thread starter Coniac
  • Start date Start date Mar 13, 2014

Coniac

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Mar 13, 2014
#1
  • Mar 13, 2014
  • #1
Got a 87 with unknown miles. About to throw some 1.7 rockers on there to go with the E303 cam.

The heads are ported e7 steel heads what would be a decent set of vavle springs to get?
I've read that the trick flow TFS-2500100 can be a good choice.

Any other suggestions? ?
 

2000xp8

SN Certified Technician
Aug 8, 2003
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#2
  • Mar 13, 2014
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Before you go to far with this project, what exactly do you know about the port work on the heads?
 

mikestang63

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Aug 27, 2012
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Mar 13, 2014
#3
  • Mar 13, 2014
  • #3
Unless you are in love with those heads or running Trophy Stock, I wouldn't invest a dime in E7's.
 
Reactions: GoldenEagle91 and 2000xp8

2000xp8

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#4
  • Mar 13, 2014
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mikestang63 said:
Unless you are in love with those heads or running Trophy Stock, I wouldn't invest a dime in E7's.
Click to expand...
Agreed.
I figured i'd ask on the off chance he had some that were documented to be well ported.

Realistically i too wouldn't dream of spending any time or money on a cam or springs for e7's.
If they were really ported right, whoever did it probably would of changed the springs already.
 

7991LXnSHO

wanna catch the space herp
10 Year Member
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Mar 13, 2014
#5
  • Mar 13, 2014
  • #5
Let's say the heads were free or are for a stock appearing class. Can we answer the spring question?
 

Grabbin' Asphalt

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Mar 14, 2014
#6
  • Mar 14, 2014
  • #6
For approximately your extra .535 lift from .498 with 1.7 rollers the Gt40 springs are within the specs. Some like them, some don't but your lift is not so extreme so either kit would work fine IMO.
 

Coniac

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Mar 14, 2014
#7
  • Mar 14, 2014
  • #7
Cam is in the car already. Was going to change the heads to gt40 heads but didn't because the e7 looked ported so it's the same stock gt40 ported e7.
It's a boost car so I'm not worried too much about heads I can still make the power I want.

I have new 1.7 rockers laying around I figured that would help a bit so I just wanted to freshen up the springs.

If it wasn't a stock block I would get better heads but with my setup it's a waste of money.
 

Grabbin' Asphalt

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#8
  • Mar 14, 2014
  • #8
If I'm "ADDing" to normal NA use, blower, n02, .... then if it were me I would make darn sure the springs can handle the extra load response etc, ....get better ones than what I just said IMO.
 

Coniac

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Mar 14, 2014
#9
  • Mar 14, 2014
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So what should I get then? Thanks
 

Grabbin' Asphalt

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#10
  • Mar 14, 2014
  • #10
Call comp cams and see what they say.
 

A5literMan

At least it is lumpy...
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Jul 30, 2011
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Mar 14, 2014
#11
  • Mar 14, 2014
  • #11
I've been running stock remanufactured springs on my e7's with 1.6 rr/e303 for 3 years. Not exactly the same so don't know how much help this is. I'm with Grabbin' call Comp or another cam manufacture for their recommendation.
 

2000xp8

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#12
  • Mar 14, 2014
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I ran a cam close to an E with 1.7's and the valves floated.
My stupidity for even putting a cam in there with E7's.
 

7991LXnSHO

wanna catch the space herp
10 Year Member
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Mar 16, 2014
#13
  • Mar 16, 2014
  • #13
Someone must have upgraded the springs when porting my E7s and putting in the cam. I have all the supporting parts for an eventual head upgrade on already, and it sure out scoots a stock head and cam motor. I am looking forward to TFS or AFR heads someday. With well ported E7s, I do not think GT40p's would be worth the time.
 

2000xp8

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Mar 16, 2014
#14
  • Mar 16, 2014
  • #14
7991LXnSHO said:
With well ported E7s, I do not think GT40p's would be worth the time.
Click to expand...
Look up powerheads and thumpers.
Those are well ported professionally done E7's. The power heads are actually Cnc'ed.
They also produce less power than stock gt40 irons or P's, which is why you no longer hear about them around here anymore. The firestone tire disaster was the best thing that ever happened to the mustang hot rodder. Pretty much put an unlimited supply of gt40 heads on the market.

But if you must, i'm pretty sure springs that go gt40 heads will also work on E7's. Just do a little more research, info has got to be somewhere around here. Or check into what powerheads or thumper used.
 
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