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Flexible pipe off of an import car will work to bridge that gap if you don't have room enough to bend up an "S" pipe. Hondas and Subrus I have seen up on the rack use a three inch or so in diameter by six inch flex coupling (I'm quiet sure it will be metric in size, but something big enough exists) to compensate for the motor doing the shimmy shake.

Diesel pick-ups and marine applications use similar flexible pipe to allow the motor to move without breaking apart the fiberglass transom or the frame of the truck. Just a matter of shopping for the correct size (application) and then finding the cheapest vendor on line.

Big Dave
 

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Discussion Starter #22
These are the headers we used on my son's 67 impala. The fit was good and a exhaust shop bent the pipes past the headers.
 

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Dave and Larry, thanks for the input.
I ended up having my local exhaust shop bend 2 pipes for me with a 45 degree angle. I then cut the ends of the pipe and the header collector and welded them together to create the offset that I needed. The angle cut and weld takes much less length than another bend would have, so it works well. Obviously there is a little more restriction than a nice gentle bend would be, but for a street engine, the 2 1/2 inch pipes will still flow plenty.
If I were doing it again, I would look to find 2 mandrel bent sections of pipe with the 45 degree bends. The front sections of pipe that go into the x section of the Pypes kit I bought would work perfect.

 

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I have the same headers installed on my 283 (soon to be 327) But the only issue I've had is that the paint seems to get baked off and easily scratched during installation. When I swap the motor in the future I plan on sanding them down and putting a better coat of high temp paint on plus re installing them a little more carefully.
 

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On my old 67 Camaro I really liked the look of high heat white. It was a pain to keep them looking good. I stick with black now.
 

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I had mine ceramic coated. Much more durable than paint and wont dull like the silver coatings you can get these with.




I also added some V-band clamps because the 3 bolt clamps will eventually leak.


 

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I had mine ceramic coated. Much more durable than paint and wont dull like the silver coatings you can get these with.




I also added some V-band clamps because the 3 bolt clamps will eventually leak.


Wow that is the nicest engine compartment, looks like a late model V8 by the oil dip stick on passengers side.
Can you give us a few details.
 

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Wow that is the nicest engine compartment, looks like a late model V8 by the oil dip stick on passengers side.
Can you give us a few details.
Thanks! It is a late model 355 1pc RMS block with an LT4 Hotcam and Trick Flow heads. The barge ran a 13.7 with a 2004R and 4.88 gear.
 

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Removing spark plug and bolt up

dadstoy am thinking of getting these pipe for my 66 is it easy to change the plug when servicing the engine cause I have a set of block hugger and its a nitemare changing the plug at the moment. Also are they easy to bolt up cause the one I have now you can't get a socket on the bolts to tighten them.

I have all the brackets for the alternator cause it's the same set up cheers
 

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Discussion Starter #30
They bolt up easy. I think only one plug is tough to get to.
 

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I wish they would just make a 1 3/4 header for us guys making bigger power. I have these headers and while they do fine they are sure holding back my stroker but looks like I have a guy tht will make some for me. Will post up pics when he finishes them. Gunna have them coated as well and do the v-band I hate header leak noises haha
 

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Has anyone gotten the cheapy Ebay Stainless headers?

I looked at it says they are 304SS

good stainless long tube headers for under 200 bucks is pretty temping.
 

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Big Dave (knower of all things), if I am understanding you correctly, putting headers on my 69 will require the motor mounts to be replaced (with the one most parts stores are going to give you anyway) but the alternator doesn't need a bracket because the mounting was changed in 69. Ultimately, I change the motor mounts and I am good to go with the headers?

What size collection pipe do folks recommend? My son's firebird (89) has 3". I know opinions on brand of header are all over the place, but is there a reasonably priced set that folks seem to like? We used hooker shorties, but being a bit older, long tubes fit these babies.
 

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The mounting bracket for the alternator was removed from the exhaust manifold castings in 1969. The long water pump brought the accesories in closer to the motor (to reduce a growing tendency to throw V-belts). The new W shaped log manifold instead of ram's horn exhaust manifold introduced in 1969 doesn't need any kind of alternator adapter if you install headers.

Header collector size is related to the primary tube size. An inch and a half primary tube header will have about a three inch collector four to six inches long. As the tube size approaches two and a half inches for the primary tube the collector has jumped pat three and a half inches to to four or six inches in diameter and the length is approaching twenty inches. These bigger primary tube headers are often equal length, and wrap around your car frame (they are installed in segments) and the collectors do not have a flange to bolt on tail pipes because they are designed for race only vehicles.

I am at a loss on changing motor mounts as you don't need to change them to install headers in an Impala (with a big block in a Nova or a Camaro that is a different issue). The only time you change a motor mount is if they break. With glued together motor mounts expect them to break often. That is why I recommend HD interlocking motor mounts that will not break.

This thread is two to three years old and I never talked about it so I was wondering how I got involved or how motor mounts are involved.

Big Dave
 

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The bracket and the five ton cable that encircles the upper control arm cross shaft is GM's answer to Ralph Nader's instigated safety recall and law suit resulting from broken motor mounts. (do not loose those parts as they are very valuable do to rarity today). That strap limits the motor's movement when the motor mount breaks. It will not work with tubular steel headers as it relies upon the structural strength of the cast iron manifold to hold the bracket in place. The reason those parts are so rare today is everyone that installed aftermarket headers threw those parts away. They were installed on every Chevy made after 1958 that was brought into their local dealership to get the cable installed for free, because of the first federally mandated product safety recall in history.

If you go to tubular headers you will need to replace your simple vulcanized rubber (glued together) motor mounts for a 1958-'68 year car (you want the short and wide and not the tall and narrow size used on newer cars from 1969-'72.

The dimensional size of the motor mount changed in 1969 and up through 1972. Most parts stores not only stock the newer style, but they will try and hand it to you if you ask for a SBC motor mount because the computer says it fits: they will not fit on your car as you need the older style mount. You want a one that is interlocking; so ask for one off of a 1966 360 horsepower 327 SBC Corvette engine to get the correct tall short and wide sized part the first time out. (measures 2-5/8th inch between the tangs and the hole in the tang is 1-3/4 inch from the block's mounting surface).

Energy Suspension GM Motor Mounts | JEGS

Headers make a big performance boost and they do so by restoring lost horsepower caused by the cast iron manifold allowing one cylinder to bleed exhaust gasses into an adjacent cylinder polluting the fuel air charge with spent gases (works just like an EGR valve). That one polluted cylinder yields most of the 25 to 30 horse gain caused by bolting on headers.

Where headers cause issues is in installing an alternator on an older car without accessory mounting holes machined into the heads (1968 and up). The older 1958-'68 Chevy used longer brackets that allowed the V-belt to fly off at high RPM. To fix this issue Chevy went to the long water pump in 1969 and brought the accessories in closer to the motor (used shorter V-belts) with all new accessory brackets that bolted to the cylinder heads.

As noted the older cars require the aftermarket bracket to mount the alternator relying on a stamped steel part that he had to bend to get it to fit. Unfortunately the stress on the alternator will easily bend that bracket out of alignment again unless reinforced (gusseted).

Big Dave
I think he's talking about this Dave.
 

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What headers are you talking about in the original post?
I'm looking for new headers for my -68 327, any suggestions for best torque?
 

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Recommend Doug Thorley Tri-Y for building torque. Longer the primary and the collector the more torque you will build in the bottom end and mid range. Hooker was the go to header for peak horsepower with larger primaries and shorter lengths for land speed records, and high bank ovals. Drag racers also loved them (due to heavy marketing and advertising), but I think building torque wins more drag races than peak horsepower ever will.

Big Dave
 
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