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Question about 351-->Fox headers

I've heard two different opinions on this, and figured I'd pose the question here:

Are special 351-specific headers required to put a 351 into a Fox? I realize that a factory-style H pipe would not fit standard Fox 5.0 headers on a 351 because they'd be further apart, so if one were to plan on using an H or X pipe designed for a 5.0 one would need special headers, but how about if one were to install a custom exhaust? Would a 351 with standard 5.0 style Fox headers even fit the engine bay?

This is all hypothetical, of course - I'm still casually researching my options. I'm trying to figure out the best bang for the buck (my never ending EFI 302 VS carb 351 VS EFI 351 dilemma).

One thing: I've pretty much decided that if the 351 goes in it'll definitely be stroked. The thing's gonna need a complete rebuild anyway, so may as well go big. Maybe even 427 big :D
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

Question about 351-->Fox headers

Reply #1 –
My guess of course, but I’d say use 5.0 1 5/8 or 1 ¾  headers and make a custom X or H pipe unless I would believe some where there’s gota be someone who make 351 specific X or H pipes for fox stangs. And as for header clearance guys are putting big blocks in stangs and I never heard of any one selling specific parts for this. So it makes you think it would all bolt up. But what you said dose make sense the taller decks on the block would screw up the geometry of aligning the H or X pipe.
Hate to volunteer people but I believe SLEEPER T-BIRD 87 has a 427 in his maybe he could help.

Question about 351-->Fox headers

Reply #2 –
You can use the Fox stang headers unequal lenght. I had to modify the steering shaft. I'm using a Tublar K member and the stang mounts. Not the fluid filled mounts.
  Yes the H/X pipe will have to be widen to fit the 5.8




SCT Tuned by Me(Greg@SpeedyDyno.com)

E.T. 10.28 @ 136.5 MPH 1/4 mile: List of Mods; 351 EFI, AFR heads,AOD,Rousch 13in frt brakes,11in rear brakes, AirRide Tech air ride system, Sub frame connetors,2400 RPM stall, 3.50,BBK shorties,T62PT Turbos  air to air intercooled, Home built kit.
Car weights 3705lbs without driver:burnout:

Question about 351-->Fox headers

Reply #3 –
Sorry 5.8fastcat I’ve scene you on here plenty and the 5.8 in you name should have gave it away. ah don’t want to volunteer to many people.

Question about 351-->Fox headers

Reply #4 –
You can modify a H pipe to fit the 5.0 headers, but IMHO getting a set of 5.8 swap headers that will fit the 5.0 H pipe is a better option... Especially IF you are thinking BIG 5.8...

Question about 351-->Fox headers

Reply #5 –
As far as the headers:

http://store.summitracing.com/egnsearch.asp?N=4294923429+4294839039+4294908331+4294908282+4294924930+4294840125+115+4294871271

I was unaware you could stroke a stock Ford 351 block to 427 cubes.  I thought that was aftermarket block only with the limit on stockers being 408.
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

Question about 351-->Fox headers

Reply #6 –
The larger tube header deal can be beat to death, so I'll stay out of that. Also the large CI windsors  EAT the cylinder walls out on a block so for longjevity still with below 400 CI.  Just my 2 cents




SCT Tuned by Me(Greg@SpeedyDyno.com)

E.T. 10.28 @ 136.5 MPH 1/4 mile: List of Mods; 351 EFI, AFR heads,AOD,Rousch 13in frt brakes,11in rear brakes, AirRide Tech air ride system, Sub frame connetors,2400 RPM stall, 3.50,BBK shorties,T62PT Turbos  air to air intercooled, Home built kit.
Car weights 3705lbs without driver:burnout:

Question about 351-->Fox headers

Reply #7 –
Quote from: 5.8fastcat
The larger tube header deal can be beat to death, so I'll stay out of that. Also the large CI windsors  EAT the cylinder walls out on a block so for longjevity still with below 400 CI.  Just my 2 cents

That was gonna be my next question. 427 sounded cool, but if it's gonna eat the block up I'll just stick to 390 (or 392, or whatever that stroker size is). 390CI is a nice T-Bird-ish sounding number anyway :D
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

Question about 351-->Fox headers

Reply #8 –
Depends on the power level you are looking to make. There is a 377 ci,383 ci,393ci.
  Are you going to leave it EFI?




SCT Tuned by Me(Greg@SpeedyDyno.com)

E.T. 10.28 @ 136.5 MPH 1/4 mile: List of Mods; 351 EFI, AFR heads,AOD,Rousch 13in frt brakes,11in rear brakes, AirRide Tech air ride system, Sub frame connetors,2400 RPM stall, 3.50,BBK shorties,T62PT Turbos  air to air intercooled, Home built kit.
Car weights 3705lbs without driver:burnout:

Question about 351-->Fox headers

Reply #9 –
That I'm not certain on. To leave it EFI using Ford EFI it would cost a fortune (in addition to the special lower manifold I'd need injectors, TB, MAF, etc). I've been looking at the Megasquirt EFI system and would like to try that out, so I might go with a carb and intake with injector bungs (like the EFI Spider), then when I put the Megasquirt system together toss the carb and convert to EFI using the same manifold.
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

Question about 351-->Fox headers

Reply #10 –
I've seen servral guys running the Mega Squit and Looks like a REAL BIG pain in the A_ _.  But if you are good with a soildering iron and such (which you obvioulsy are) should be a breeze for you.
  What do you do for a baseline tune on those sytems?

The only thing diffrent with the ford EFI is you won't have to buy a MAF. But that should be ofset from the cost of the Mega Squit?
  More of my 2 cents.




SCT Tuned by Me(Greg@SpeedyDyno.com)

E.T. 10.28 @ 136.5 MPH 1/4 mile: List of Mods; 351 EFI, AFR heads,AOD,Rousch 13in frt brakes,11in rear brakes, AirRide Tech air ride system, Sub frame connetors,2400 RPM stall, 3.50,BBK shorties,T62PT Turbos  air to air intercooled, Home built kit.
Car weights 3705lbs without driver:burnout:

Question about 351-->Fox headers

Reply #11 –
Quote from: 5.8fastcat
I've seen servral guys running the Mega Squit and Looks like a REAL BIG pain in the A_ _.  But if you are good with a soildering iron and such (which you obvioulsy are) should be a breeze for you.
  What do you do for a baseline tune on those sytems?

The only thing diffrent with the ford EFI is you won't have to buy a MAF. But that should be ofset from the cost of the Mega Squit?
  More of my 2 cents.

I think the cost of the intakes would be a big difference as well - the two-piece 351 intakes are in the $600 range, while a 1-piece carb-style-with-injector-bosses intake can be had for under $200. Another advantage is that I could put a carb on it and get it running while I work on the MS system, then re-use my intake. Of course this is all very, very preliminary right now...
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

Question about 351-->Fox headers

Reply #12 –
Quote from: Thunder Chicken
I think the cost of the intakes would be a big difference as well - the two-piece 351 intakes are in the $600 range, while a 1-piece carb-style-with-injector-bosses intake can be had for under $200. Another advantage is that I could put a carb on it and get it running while I work on the MS system, then re-use my intake. Of course this is all very, very preliminary right now...


How much power are you planning on making? A cobra-GT40 setup should get you NA up to about 350 rwhp. I got my entire intake system with the exception of the TB and injectors (which you're going to have to buy anyway and they all cost about the same regardless of size) used for about 350.00. I got the GT40 upper for 200 and the lower for 150 (this was 3 years ago) off of ebay. A 351 will never run properly on the stock MAF system without a tune so to be cheap on this, I purchased a stock 5.4L lightning 90mm MAF meter new from ford for 150.00 (they're now 90.00) as opposed to the 600.00 new Pro-m. The MAF meter is the most important element for tuning an EEC car. The L-MAF is one of the most accurate ford meters on the market. It can support up to 500hp and has a range of up to 42lb per hour injectors. I then had the entire combo tuned for $270.00. Unless you plan on going to a big 5.8 (377 and up) or a supercharged standard 5.8, you're going to lose some streetability with the spyder type setup as it's meant for the sole purpose of serious upper RPM hp. But it should be easier than ever now to convert a 5.8 to EFI and not have it cost a limb. I would definetly keep it and I'm going to quote Tom when I say you're going to have to pry my EFI from my cold dead fingers.
Duckin' agents like we was trapped in da matrix!

Question about 351-->Fox headers

Reply #13 –
i used mac 5.8 mustang shorties in my 87 cat 5.8
[SIGPIC][/SIGPIC]

Question about 351-->Fox headers

Reply #14 –
You can purchase a Pro Products Typhone intake( copy of Eldebrock)
 351 upper and lower for about $375.

Just let your wallet be your guide.




SCT Tuned by Me(Greg@SpeedyDyno.com)

E.T. 10.28 @ 136.5 MPH 1/4 mile: List of Mods; 351 EFI, AFR heads,AOD,Rousch 13in frt brakes,11in rear brakes, AirRide Tech air ride system, Sub frame connetors,2400 RPM stall, 3.50,BBK shorties,T62PT Turbos  air to air intercooled, Home built kit.
Car weights 3705lbs without driver:burnout: