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Discussion Starter #1
Hi guys. I'm building my first turbo car. My intent is to turbo a bone stock '94 GT minus emissions equipment. I'll be installing a larger in take pump, blow thru MAF and 80lb injectors. I've read and heard that I should run head studs and better valve springs in the E7 heads. I've also read that the heads can still lift with studs and that the stock valve springs are fine. The engine has 53k original miles for reference.
 

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IMO, springs are cheap and easy to upgrade. Better to do it now vs when you have too b/c the springs can't hold the extra pressure from boost trying to keep them open.
Remember, if the spring is installed with a seat pressure of 90psi and you run 10psi of boost the spring essentially has 80psi of seat pressure under boost...

ks
 

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Discussion Starter #3
IMO, springs are cheap and easy to upgrade. Better to do it now vs when you have too b/c the springs can't hold the extra pressure from boost trying to keep them open.
Remember, if the spring is installed with a seat pressure of 90psi and you run 10psi of boost the spring essentially has 80psi of seat pressure under boost...

ks
Hi Kevin. I guess at that point; I might as well purchase cheap aluminum heads. Then comes head studs, rockers, gaskets and larger rocker studs. It never ends. Lol.
 

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You can get better springs for the stock cam specs from Alex's Parts for like $150 bucks or less. More is you want to spend more. As for head studs, how much boost will you be running? If the heads are on and don't need to come off, leave it be. If they have to come off for head gaskets later, put them in then. You can install the springs with the heads on the car with the air compressor/spark plug adapter tool.
 

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LOL... If you plan to upgrade later then.... =)

ks
 

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Discussion Starter #6
You can get better springs for the stock cam specs from Alex's Parts for like $150 bucks or less. More is you want to spend more. As for head studs, how much boost will you be running? If the heads are on and don't need to come off, leave it be. If they have to come off for head gaskets later, put them in then. You can install the springs with the heads on the car with the air compressor/spark plug adapter tool.
I've dealt with Alex before. I'll give him a call. He always has sound advice.
 

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Discussion Starter #8
I'm thinking 10-12 psi. I've never boosted before so I have a lot to learn.
 

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I'm thinking 10-12 psi. I've never boosted before so I have a lot to learn.
I’ve been down this road before just as your are. You can put studs in without pulling the heads off, drain the coolant and do one at a time then re torque everything. Springs are a good idea but if your using stock cam I’d run it and save my money for now. I’d start at 10 pounds of boost and see how that works out. Let me know if you have any other questions


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I’ve been down this road before just as your are. You can put studs in without pulling the heads off, drain the coolant and do one at a time then re torque everything. Springs are a good idea but if your using stock cam I’d run it and save my money for now. I’d start at 10 pounds of boost and see how that works out. Let me know if you have any other questions


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Thank you. Are you recommending studs? I'm not sure and it's been a long day. Lol
 

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IMO, springs are cheap and easy to upgrade. Better to do it now vs when you have too b/c the springs can't hold the extra pressure from boost trying to keep them open.
Remember, if the spring is installed with a seat pressure of 90psi and you run 10psi of boost the spring essentially has 80psi of seat pressure under boost...

ks
It's actually less. It is the square inch of the valve diameter minus the diameter of the stem.
 

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It's actually less. It is the square inch of the valve diameter minus the diameter of the stem.
I know...that's why I said "essentially".
 

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Discussion Starter #13
I remember now why some say not to use head studs on an untouched stock engine. The concern is the studs altering the bores when tightened. If one were to have the block machined; a torque plate and studs would be used to machine the bores correctly. No? I would assume that Ford has the bores set up for the factory head bolts tightened to spec. Studs have more clamping force but they pull on the block as well as the heads.
Thoughts?
 

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What are you doing for engine management? 80lb injectors are way overkill and you will just be hurting your ability to tune at idle. I had 42lb injectors on a gt40p head car with Edelbrock intake and larger throttle body, I was close to maxing them at 10-12 psi but you will be down a fair amount of power from that. Make sure you put in a larger fuel pump than stock as well. 255lph will be fine and is drop in.

I never had an issue with valve springs but lifting the heads was an issue so I'd recommend studs.
 

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As soon as you see “cheap heads” being talked about

its pretty obvious this will not turn out well, and tuning has not even been thought about
 
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Discussion Starter #16
What are you doing for engine management? 80lb injectors are way overkill and you will just be hurting your ability to tune at idle. I had 42lb injectors on a gt40p head car with Edelbrock intake and larger throttle body, I was close to maxing them at 10-12 psi but you will be down a fair amount of power from that. Make sure you put in a larger fuel pump than stock as well. 255lph will be fine and is drop in.

I never had an issue with valve springs but lifting the heads was an issue so I'd recommend studs.
You might want to do some research on tuning as well as on Deka 80lb injectors. These injectors will not effect tuning in a negative way.
 

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Discussion Starter #17
As soon as you see “cheap heads” being talked about

its pretty obvious this will not turn out well, and tuning has not even been thought about
Please tell me about your personal experience with Promaxx heads. I'll be glad to tell you about my negative experience with my out of the box AFR 185's.

How did you conclude that tuning hasn't been thought about?
 

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Ford built a sloppy 302 that lasts, because it's a sloppy engine. There is no thought about studs or bolts when machining these 30 years ago. Some of the production machine work that was done was definitely done by stevie wonder. Tolerance is all over the place. Put studs in it
 

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Discussion Starter #19
Ford built a sloppy 302 that lasts, because it's a sloppy engine. There is no thought about studs or bolts when machining these 30 years ago. Some of the production machine work that was done was definitely done by stevie wonder. Tolerance is all over the place. Put studs in it
Studs it is. Thanks Woody.
 

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You might want to do some research on tuning as well as on Deka 80lb injectors. These injectors will not effect tuning in a negative way.
I built my ECU from bare components and tuned it myself, I know a little about tuning.

Its simple, there is X resolution available for tuning injector pulsewidth. At low rpm low load you need a very small amount of fuel. When you get injectors that are double the size you need you half the resolution you have to tune with. At high rpm that's not an issue, but at low rpm that's the difference between a stable idle and the surging bucking nightmare so many guys fight. The majority of tuners focus on peak numbers and ignore drivability.

Newer injectors do have much better pintles that improve the fuel atomization compared to the old ford green tops but there is zero benefit in going double the size you need. Search for "fuel injectors too big" and you will see dozens of people explaining this.
 
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