SUPER SIX HEADERS

Charrlie_S

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AJ, I know where you are coming from, and agree with your logic, but disagree with the method. The best bang for the buck in gaining performance form a slant is increase the compression ratio. The stock ratio was advertised at any where from 8.2 to 8.5 to 1. I can't tell you how many slant engines I have taken apart, and not a single one actually measured higher then 8.0 to 1. Most were in the 7.8- 7.9 to 1 area. You can mill the head to get around 10-1, but that is not feasible for a DD street engine. Mill to get between 8.5 and 9.0, and you gain torque throughout the RPM range, which also equates to more horse power. You will also gain MPG. no other changes are required. There is no downside to raising the CR within reason. And it can be done for less money then a converter (which CAN hurt MPG), or a gear change. Then any other mods, if wanted, will be more effective, also
 

Oldiron440

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I agree and I thought that was part of the plan or did I miss something.
 

AJ/FormS

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AJ, I know where you are coming from, and agree with your logic, but disagree with the method. The best bang for the buck in gaining performance form a slant is increase the compression ratio. The stock ratio was advertised at any where from 8.2 to 8.5 to 1. I can't tell you how many slant engines I have taken apart, and not a single one actually measured higher then 8.0 to 1. Most were in the 7.8- 7.9 to 1 area. You can mill the head to get around 10-1, but that is not feasible for a DD street engine. Mill to get between 8.5 and 9.0, and you gain torque throughout the RPM range, which also equates to more horse power. You will also gain MPG. no other changes are required. There is no downside to raising the CR within reason. And it can be done for less money then a converter (which CAN hurt MPG), or a gear change. Then any other mods, if wanted, will be more effective, also
Been there done that, gears and TC was better, by a ton. Gas mileage tanked but for performance, I didn't care,it wasn't my DD.
More compression with the SuperSix stuff and no TC/gears, was very disappointing. Comparitively speaking, compression on the start-line counts for almost nothing; you gotta get the revs up a little more than 1750.
The TC was awesome....The TC and gears doubly so.......Compression brought some mpgs back, even with the bigger cam.......My experience.But I wouldn't do it again. Three times with slantys and I'm done with them,forever.

Headers and duals will cost waaay more than a TC; you can probably get a TC and a used 7.25 case with SG and 3.55s for about the same amount.

If you want performance from 90hp, you gotta give something up......... unless you supercharge it, and then it drains your bank account.
 
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Oldiron440

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Been there done that, gears and TC was better, by a ton. Gas mileage tanked but for performance, I didn't care,it wasn't my DD.
More compression with the SuperSix stuff and no TC/gears, was very disappointing. Comparitively speaking, compression on the start-line counts for almost nothing; you gotta get the revs up a little more than 1750.
The TC was awesome....The TC and gears doubly so.......Compression brought some mpgs back, even with the bigger cam.......My experience.But I wouldn't do it again. Three times with slantys and I'm done with them,forever.

Headers and duals will cost waaay more than a TC; you can probably get a TC and a used 7.25 case with SG and 3.55s for about the same amount.
Your a crusty old fart, it's your way or no way. :)
 

Charrlie_S

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AJ, don't take this the wrong way, I'm not into a pissing match with you. We are both correct, but you are talking about fuel mileage not being an issue, and I am talking about a DD, where fuel mileage is an issue.
PS: I am/was a fan of the 7 1/4, but no longer. Getting hard to find parts, especially for the sure grip, and then they are pricey. Better to use a different rear completely. Might not be cheaper, but at least parts are available.
 

AJ/FormS

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Your a crusty old fart, it's your way or no way. :)
It's not that at all, I just hate to see a guy spend a G and then find out he spent it on the wrong thing, and still has to do the TC and gears thing, ........... I've been doing this for 50 years and I've made every mistake that can be made...... at least once,lol
 

AJ/FormS

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AJ, don't take this the wrong way, I'm not into a pissing match with you. We are both correct, but you are talking about fuel mileage not being an issue, and I am talking about a DD, where fuel mileage is an issue.
PS: I am/was a fan of the 7 1/4, but no longer. Getting hard to find parts, especially for the sure grip, and then they are pricey. Better to use a different rear completely. Might not be cheaper, but at least parts are available.
No offense taken,
 

Duke5A

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Dad did a Clifford build on a 258 Jeep six in a full size Cherokee. Ported head, big valves, 10:1, Clifford header and intake, cam also from Clifford. Ran good, but honestly, it was still a six. A dollar spent on a V8 goes twice as far.

I'm not trying to poo poo inline sixes. I'm actually in the planning stage of building a Ford 300 for my 1992 F-150. I want it to keep up with modern six bangers, but still have driver manors. I made up my mind it's going to be boosted, but I'm unsure of whether to super charge it or turbo - leaning on super charging.

Kind of unrelated...a buddy of mine has a 225 /6 aluminum block. Needs a sleeve, but I'm he'd be willing to part with it.
 

tallboy

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Done to my stock SuperSix '77 Wagon: One of the cheapest and most effective modifications, is to ditch that propeller in front of the engine! The fan runs at engine speed, and robs you of 5-7 hp. (it always scared the hell out of me when I leaned over it!) Replace the stock fan, and it's shroud if it has one - a simple bolt-off - with a used twin or single electric fan setup from any car with app. the same physical size radiator. Get a complete setup in a shroud, it doesn't matter if you choose a pull or push fan setup, but with the stock fan out of the way, there is plenty room behind the radiator. There are several ways to activate them, Summit, Jegs and others have lots of cheap temp. sensors and other hardware. With twin fans you can even have a two-stage activation, if you live in a hot climate. Use a relay that can take the current needed to activate the fan(s), preferably the one from the donor car.
Another low-priced boost is to replace the stock ignition - which really isn't very good - with an external GM HEI ignition module setup, an E-core coil, a set of good (Magnecore?) low-resistance spark plug cables and NGK UR45IX spark plugs (NGK#7559) with iridium center electrode. Then recurve the distributor by changing the springs for the advance weights. Those mods come at a low price. The ignition mods will probably not give more than 3-5 hp on a dyno, but it will give that over most of the rev curve, and also comes with a big grin, as it improves the driveability enormously! It will also improve the efficiency of the engine, and thus improve the mileage.
 
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