Fox What to do with heads

Bullitt347

I have been doing it wrong this whole time
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? I feel like I'm giving up a lot of power as I'm losing compression with the aluminum heads.

Thanks for all the help.
All things being equal, you will ALWAYS make more power with aluminum heads. The compression loss from the aluminum heads would have to significant to see a power drop off. Never mind the 50+ lb advantage the aluminum heads give.
 
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TOOLOW91

If you're the village idiot what's that make me?
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All things being equal, you will ALWAYS make more power with aluminum heads. The compression loss from the aluminum heads would have to significant to see a power drop off. Never mind the 50+ lb advantage the aluminum heads give.
Thank you . He could prob mill 3-4cc out of the chamber and be ahead
 
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Jimmer009

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Yea stock fuel pump. That will change this winter. I think I'm just going with a Turbo build. I have some experience with them I had a b5 s4 and really liked it. And it sounds like a fun winter project.
 

FastDriver

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Unless something's mechanically wrong, leave what you have in there. Jimmer, go down the turbo path if you want to, I have 2 turbo foxes, but have the whole plan ready to execute before you tear the car apart. Most turbo projects end with a sold car that's still on blocks. That said, if you have a complete solution before you start, understand the full cost and labor requirement before you get to work, then 500 hp (at crank or tires) is definitely doable.

Some people put a lot of money into a stroker kit, super duper heads/cam/intake etc... The truth with an intercooled turbo car is that at 15psi on pump gas, you can turn a 250 rwhp car into a 500 rwhp car, as long as you have the tune and fuel system to support it. Further, the stock block is never going to be reliable beyond that power level, regardless of the rotating assembly, or block reinforcement. So, when turboing I'm the biggest fan of keeping the H/C/I combo simple and putting your time/effort/money into getting the turbo kit right. Plus, it makes it a lot cheaper to replace the shortblock when it's just the stocker, not anything special.
 
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CAMTWO1070

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From what I see you are missing the camshaft specs and type plus from what I remember from when I was looking for heads for my 408w extreme torquer low rpm low buck project out of the box all of their sbf heads have a .550" max lift and rev to 5500rpm's max and are for flat tappet camshafts only too like my Edelbrock E-Street heads so if you wanna run a roller cam larger than .550" lift or even rev higher than 5500rpm's Id go with better heads...
 
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A couple of thoughts; first you may want to sell the Speedmaster heads and buy better ones. They barely flow better than stock cast iron GT40's.
View: https://youtu.be/BU2zuT4eoWk
Secondly, if you put those heads with a 2.02 valve and an X303 cam on a stock piston, I'm betting you have some bent intake valves which are leaving you with the disappointing power levels from what you were expecting. With a 500hp goal I'd recommend you go with a 408W with a good set of heads (AFR or TrickFlow) and a XFI-236 Comp. cam. This combo should give you around 530 flywheel hp with a Performer RPM intake or around 550 with a Victor Jr. If you want to stay with the 302 block, a 347 strocker kit is in order :)
 

2000xp8

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Interesting video, so speedmaster heads are really pro comp heads?
At first thought, i figured if he already has aluminum heads, send them out, valve job, milling etc.
Now knowing they are pro comp, sell them.
If that video is correct and the aluminum is of poor quality, i'm sure that's not good for stuffing boost into them.

IMO, Forget about the turbo setup, me personally i don't ever see a turbo setup as something that should be done on a fixed budget, because there is about zero chance the budget holds.
 
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rednotch

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Yes speed master and pro comp are the same thing....the majority of there stuff is garbage. There's a few China sbf sourced heads and if there decent they get rebranded like crazy , only 3 I would use, is the dart 180 clone. That's the casting afr uses as the enforcer.

Promaxx sells the other 2 but others have as well. The maxx series is mostly an edelbrock clone. The same basic casting was used for the sbf heads lmr/sve used to sell and had a few as cast options.

The other head they have the x series it is mostly an afr205 clone, but can be order with smaller as cast ports, its becoming like the afr enforcer head, in the way everyone is starting to private label it.. Flotek sold it as the 2005 hammer head, dart is now hawking it as the Shp 205.. Yep even dart is doing the China head deal now... It's probably the best " budget " head a DIY guy building a decent set up not using a stock bottom end could pick up right now.

View: https://www.youtube.com/watch?v=qifIFi3icN8
 
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Yep, I'm embarassed to admit it, but I tried a set of Speedmasters. They took soooo much work to get decent numbers out of them... I could have bought a good set of heads for less money than I had to invest into them. Not to mention the pending sense of doom you feel on every pass crossing your fingers that they don't fail.
 
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2000xp8

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Yep, I'm embarassed to admit it, but I tried a set of Speedmasters. They took soooo much work to get decent numbers out of them... I could have bought a good set of heads for less money than I had to invest into them. Not to mention the pending sense of doom you feel on every pass crossing your fingers that they don't fail.
You aren't the only one that has bought those heads or others like them, you just may be the first around here to admit you bought them and they were crap.
 

Jimmer009

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Sorry I didn't get back to you guys for awhile. I guess I need to look for better heads. I got a good deal these heads. So I'm not out much. So does anyone have a set of heads for sale??? I have a 351w block. But it needs everything as I cleaned it using electrologists. But I can do it all in house. Just need to get past Xmas
 

Jimmer009

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Jan 4, 2022
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Sorry I didn't get back to you guys for awhile. I guess I need to look for better heads. I got a good deal these heads. So I'm not out much. So does anyone have a set of heads for sale??? I have a 351w block. But it needs everything as I cleaned it using electrologists. But I can do it all in house. Just need to get past Xmas
And another thing, I don't plan to stay in budget, and I'll never sell the car. Unless I could go directly and buy a better foxbody.

I'm gonna do a compression check this week and I'll report the numbers. I hate to say it's a bent valve as it runs good. I really am leaning more on the intake being restriction. I see there cheap heads, I wish I got better ones. But I'm gonna keep my eyes open for a deal on a better set.

Either way I go on the build turbo or n/a, it will be ready for the spring. But I do agree with spending the money on 351w. It's just turbo is cheaper I need all new bearings and freeze plugs before I even start with the cool parts.
 

Jimmer009

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Jan 4, 2022
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And another thing, I don't plan to stay in budget, and I'll never sell the car. Unless I could go directly and buy a better foxbody.

I'm gonna do a compression check this week and I'll report the numbers. I hate to say it's a bent valve as it runs good. I really am leaning more on the intake being restriction. I see there cheap heads, I wish I got better ones. But I'm gonna keep my eyes open for a deal on a better set.

Either way I go on the build turbo or n/a, it will be ready for the spring. But I do agree with spending the money on 351w. It's just turbo is cheaper I need all new bearings and freeze plugs before I even start with the cool parts.
And another thing, I don't plan to stay in budget, and I'll never sell the car. Unless I could go directly and buy a better foxbody.

I'm gonna do a compression check this week and I'll report the numbers. I hate to say it's a bent valve as it runs good. I really am leaning more on the intake being restriction. I see there cheap heads, I wish I got better ones. But I'm gonna keep my eyes open for a deal on a better set.

Either way I go on the build turbo or n/a, it will be ready for the spring. But I do agree with spending the money on 351w. It's just turbo is cheaper I need all new bearings and freeze plugs before I even start with the cool parts.
So I did the compression check. I did do the motor cold. And I did the fuel pump off and work. All cylinders ranged from 110-130. I had the also tested the valve springs. Coil bind is .575, 300lbs cracking pressure and 150 compression. I think my restriction is just my intake. Tmoss or trick flow will probably be my next step.

I do think the xcam is not the best for what I want to do. It moves the power curve and the lost torque makes it feel doggy. Especially with a restrictive intake.