Progress Thread Finally got a new truck

1.7 rockers will work for a bit more fun?? Reading about it some say its good, others say way too minor. How much fun karthief?
Not much really but it would be better than throw'n money away on those bare castings, the whole point is to save up for better stuff, look, I've been agonizing over installing a set of 'p' heads or going with aluminium heads, I using the 'p' heads because they are basically new, I had them on another engine so I know how to make the spark plug angle problem work and I know I'll not be racing hemi chargers with it. But it will be 'fun'.
 
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Some people claim just a set of 1.7 rockers gets 10-15 hp. I would consider it for 180 bucks . You dont have to tear the engine down that way. Plus you gets added smoothness and breath ability.
 
I’d hold out for a complete set of 3 bar heads. The 4 bar (GT-40P’s) have a different spark angle that can make header and plug wire fit problematic.

As I said before, just did a GT-40, explorer intake, b cam combo on a friends car. It’s a great, proven combination. Will it make the same power as an aluminum head? Of course not. But it’s a proven 280 rwhp combo. That’s a lot of fun in a foxbody.
280 is not bad at all - that's about 100HP more than stock. On a fox, that could get you into trouble in a hurry.
 
I think there is some overly optimistic estimates here.

280rwhp is very unlikely with gt40 iron parts.
You can probably expect 250rwhp to 265rwhp.
An improvement? Yeah, worth the effort of stripping the engine all the way down, i don't think so.

1.7 rockers on stock heads will do almost nothing.
I know, i've done it. I wouldn't waste my time or money.
Especially since most cams are designed for the use of 1.6's, so if you change the heads and cam later, they may not be of use.

IMO, look for deals on better parts (such as aluminum heads) as you find them. I'd say most of us at one time or another collected parts. You don't "need" them right now. If it takes a year, it takes a year, the good news is that you won't have to do it twice.
 
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I rememeber when I was hell-bent on my GT40P combo with TFS1 cam. Once I started gathering all the little parts, and looking at the cost of new springs and having a valve job done on the 40P's, it just wasn't worth it for the amount of work and the meager HP gain.

Don't get me wrong, I still think GT40/Cobra/common cam is a pretty basic combo, but to make it worthwhile you almost need to slap that combo together on a motor you don't care about and call it a day. If you are going to go through the trouble of a meticulous rebuild, use better parts.


But this is one of those things where everyone will have a different opinion on. I built my motor with my parts for my reasons. Your reasons might be different. I would say though try and find a good head, and then build around that.
 
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I think the main driver here is budget. It can be done right for around $1000. The key is finding heads that don’t need work as that would blow the budget. Here’s how we did it.

Explorer Intake $50
Explorer TB $40
GT40 heads (3 bar) $300
Trick Flow spring kit $170
Hardened push rods $110
B303 cam $100
New timing chain $44
Cobra 1.7 roller rockers $160
SN95 valve covers $80

Thats $1054. Done right. No tall valve covers. No intake spacer. No hood clearance issues. Proper rocker geometry and a OEM baffled PVC system.

I can understand wanting only to do it once and waiting for used aluminum heads. I have no dog in this fight. Too each his own. My friend was on a very tight budget and this is how we did it.
 
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I would love to get a nice set of AL Heads and do it once. I know that there is a pretty good difference between those and cast iron GT40 heads. I do have an Explorer intake I pulled from a pull and pay a few years back, and have a TFS1 cam in the works. I haven't been in any major rush to do this swap, just something Id like to do in the near future. This is something I don't want to have to do twice. I understand that there are many variables that go along with making a decision on what parts to use. Simply put, when and if I get this done I want this engine to be reliable, street friendly and perform well. Im not looking to get into a headache of cheap/mismatched parts that will make me suffer and regret my decision. What would be a good head to start with @Mustang5L5?
 
Where are you at? I know of at least one set of explorer heads that need no work (already worked over) you could pickup.
In reality those bare heads are parking stops, cores. Only reason to use explorer heads would be they need no work and almost free.
If it's a cruiser and just for fun stick some 1.7 roller rocker on the e7s and save your money for some aluminium heads.
I’m not opposed to using the right set of GT40 heads of that will help me save some cash and throw me back in the seat a little more. :burnout: @General karthief
 
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Have you checked out that thread I linked? Page 5 contains a video about selecting the proper cam shaft. Since it seems you've already selected a cam, the video can still be relevant concerning heads, you'll want to match flow numbers to your cam. That cam has an advertised max lift of roughly .500, so you'll want good flow at that lift number on both sides. And again, as referenced in that thread and the heads I'm eye balling, Pro Maxx heads can be had for <$1k and flow well at those numbers. There is also someone here on the forums who has vouched for them so far. But those Pro Maxx's have been on sale in the recent past and could be had for around $800. I'm hoping they'll have a Black Friday special and drop to that price again now that I have the disposable income.

I have Trick Flow Twisted Wedges on my Cobra II with a cam that's meant more for low end torque (as per the manufacturer's description) and they perform well (as you'd expect from Trick Flow....). But you're going to spend more for them. The Pro Maxx is advertised to flow the same on the intake side at .500 and slightly better on the exhaust at .500 than the TW's. They are advertised to flow better than Edelbrocks as well. Just something to chew on.
 
What's your ultimate goal?

I run the TFS170's just because it's a reputable head, and the canted head design would work with the stock pistons. I did have to change springs to work with my cam, so something to consider based on your cam choice. They pop up used but the issue with used heads is you should really have them gone through. At that point, you are at the price of a new set. Some will even argue that a set of heads out of the box also need to be gone through.

Once you go down the rabbithole...
 
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What's your ultimate goal?

I run the TFS170's just because it's a reputable head, and the canted head design would work with the stock pistons. I did have to change springs to work with my cam, so something to consider based on your cam choice. They pop up used but the issue with used heads is you should really have them gone through. At that point, you are at the price of a new set. Some will even argue that a set of heads out of the box also need to be gone through.

Once you go down the rabbithole...

If i was to pick between NIB heads and valve jobbed used heads at the same total cost, unless there was visible damage to the used ones, i may pick the used ones.
Valve jobbed heads with bowl clean up almost always come out 10 to 15rwhp higher.
If someone is worried about the springs (i doubt with tfs stage one there is a real worry), just buy the track heat version.

People keep mentioning Pro Max heads. But nobody includes any proof of value.
Kind of mind boggling that people even suggest them when literally nobody knows how good they really are.

Don't ignore X heads, the can usually be had cheap.
Valve job them and they will perform very well.
Be nice to do an all ford racing parts build on a clean unmolested foxbody.
 
People keep mentioning Pro Max heads. But nobody includes any proof of value.
Kind of mind boggling that people even suggest them when literally nobody knows how good they really are.

From my thread that I referenced on the last page:

I'm more than happy with my promaxx heads. The local guy around here that ports everyones heads (not just some guy, he's a pro) looked them over and thought they were very good. Castings look much better than edelebrock heads. I was very impressed. Check your springs if you get them as we thought they were a bit light. They are performing good for me on a stock bottom end with a blower at around 10psi. I will be doing a new 347 bottom end this winter. I may have them ported a bit, although the guy said they dont need much work to improve whats already there
You're right though, I have no first hand experience with them. But if their numbers hold true they don't seem like they'd be horrible for <$1000. It's enough for me to give them a shot and I think that anyone on a budget might want to consider them as well. Financially, <$1000 compared to >$1300 for TF's seems to be worth the look. There are other options as well. FloTeks, for example, have been run in a magazine comparison and had pretty good marks there. Again, that link is also in that thread. You can get Floteks for <$1000 as well, but on paper they don't perform as well as the Pro Maxx heads. And since hardly anyone has spoken up about them to give them a "yay" or a "nay" most everything said about them is hearsay, so all we have to go from is what they've advertised. :shrug:
 
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Have you checked out that thread I linked? Page 5 contains a video about selecting the proper cam shaft. Since it seems you've already selected a cam, the video can still be relevant concerning heads, you'll want to match flow numbers to your cam. That cam has an advertised max lift of roughly .500, so you'll want good flow at that lift number on both sides. And again, as referenced in that thread and the heads I'm eye balling, Pro Maxx heads can be had for <$1k and flow well at those numbers. There is also someone here on the forums who has vouched for them so far. But those Pro Maxx's have been on sale in the recent past and could be had for around $800. I'm hoping they'll have a Black Friday special and drop to that price again now that I have the disposable income.

I have Trick Flow Twisted Wedges on my Cobra II with a cam that's meant more for low end torque (as per the manufacturer's description) and they perform well (as you'd expect from Trick Flow....). But you're going to spend more for them. The Pro Maxx is advertised to flow the same on the intake side at .500 and slightly better on the exhaust at .500 than the TW's. They are advertised to flow better than Edelbrocks as well. Just something to chew on.
Ill read through that tonight @LILCBRA, thanks for attaching that. I need to read up on this stuff a little more. Way too many variables.
 
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The gt40/explorer intake + a letter cam is old school but it works for scoot'n around town and having fun, add a 355 gear and it's a dependable combo that's fun to drive.
Engine masters has a dyno test on a sbf comparing iron vrs aluminium heads, it shows where the gains are and in reality on a street car/ mild build it's not a huge difference.
I look at torque numbers, that's what rule the streets,
 
The gt40/explorer intake + a letter cam is old school but it works for scoot'n around town and having fun, add a 355 gear and it's a dependable combo that's fun to drive.
Engine masters has a dyno test on a sbf comparing iron vrs aluminium heads, it shows where the gains are and in reality on a street car/ mild build it's not a huge difference.
I look at torque numbers, that's what rule the streets,
This has kinda been my whole plan going along. I don’t mind the old school approach. Back in the day that’s what all the guys I’ve been around did. I don’t think there is anything wrong with that, plus, it won’t break the bank, too much. You said it best @General karthief, scootin around town and having fun with some added power is what I’m looking for. Is it me, why is that combo frowned upon these days? Probably because there is always something better, right?
 
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I don’t mind the old school approach. ...... Is it me, why is that combo frowned upon these days? Probably because there is always something better, right?

You hit the nail on the head right there. It seems most people want to suggest the biggest and baddest when something lesser than that will work for the intentions of the person wanting to do it. Obviously you want to get the best that you can afford, that's really what the goal is. If you don't want to drop $1k - $2k on a set of heads, then it's all about finding the best performing set you can find in the price range you're looking to spend. Don't want to spend $1k on the whole combo? Then you're looking at sweat equity on E7s or Explorer GT40s to reign in the costs. There's really nothing wrong with any approach you choose.... :shrug:
 
Because 'race car'
Like the 'big and little' wheel/tire combo, fat back tires and skinny front runners look 'race car' cool till you have to make a hard turn and brake at the same time, that will pucker your butt and make it hard to pull the upholstery outta your azz.
The main problem with the letter cams is what made them so cool at idle, the rowdy idle sounded cool but you had to jack it up to 900-1000 rpms to keep em ffom stalling (most times) then the car would buck when trying to schlep around a parking lot in first gear under 1500 rpms. Some say this can be 'tuned out with a chip' and likely was done back in the day. The new modern cams are ground for idle quality and better performance mid range,
Again it's all in the plan of the build, technology has produced better cams/heads and intakes, the important thing is to be realistic with what you are going to do with the car.
When asked most people will tell you it's a street/strip car. It's got to be one or the other, it rarely works well both ways.
 
GT40 heads + a newer cam grind then for driveability? Sure you aren't getting the absolute max POWA, but I wonder if the extra power is only available at the top end - where you spend little of your time and can go directly to jail if you get caught.

Myself, I'd be happy with 270 and ecstatic with 300 RWHP. That's plenty for the street in a car that weighs nothing and has no driver aids to pull your ass out of the sling when you screw up. Most of these 500+ HP factory cars only exist because of electronics that keep people out of the concrete dividing walls.

If you get really bored, you can always spray it. I've always wanted to spray a car.