• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

New exhaust advice

Share this page

C

Crisis

Jedi Hopeful
Offline
I have a new stock exhaust system (header back in SS)for my 73 TR6, bought from one of the big three. Came with fitting kit. Is this job as straight forward as it appears? Remove old, replace new? Any advice?
Also, have thought about getting the pacesetter header from Jethot (coated in/out) and installing it while I'm at it. Does anyone know if they're a good fit? Is there any performance benefit other than the lower engine temps? Advice and personal experience appreciated. Thank you.
 
Your stock cast iron exhaust manifold for the 73 is a dual manifold that will give you much better fit and durability and service than any header on the market. I would not bother changing it out as it will give you zero benefits. Headers, all of them, require lots of fitting and are not worth the effort, unless you are doing lots of other engine mods.
 
I've not changed one out but have observed whilst under the leaking beast that the exhaust pipe is routed through the middle of the "T-Shirt" frame stiffener; I thought when I looked at it that it might not be a simple job to change.
 
Crisis, you have a few things to do.

The intake manifold flanges may have to be ground slightly to fit the Pacesetter header. At least they did for my triple conversion. See below pics that show what we took off. Keep your old intake manifold gasket in place when you fit the headers as shown below. You can tell by fitting them up, if the intake will need any grinding by the pattern pressed into the old gasket.

It also makes a great template when off of the head for marking the intake as to what needs grinding. My pictures below may show what needs to be done:

https://www.74tr6.com/triplecarbinstall.htm

Next comes the collector pipe to the twin pipes going back. These did not fit on my car and I had to have a new twin pipe adapter made to fit from the Pacesetter supplied unit to the TRF stainless pipes. Unfortunately, that was done when I wasn't at the exhaust shop, after I had to have the car towed there and I don't have the "how to" on that project, but you can see the Pacesetter collector pipe here:

https://www.74tr6.com/triplecarbinstall.htm

And the exhaust as it was fit and welded in place to the old stock system here, but before the new stainless and frame work:

https://www.74tr6.com/framebefore.htm

I hope that this helps.
 
I am of the belief that there is little that is simple when it comes to replacing exhausts. Something about laying on you back with a limited field of vision and trying to see the entire picture. If you stick with the original exhaust manifold, there is a good chance you will have problems with flange studs. They can strip or break. That's when the party begins. As for removing the rest of the system, that's what reciprocating saws are for.
Make sure that everything is lined up as you want it before touching a clamp. Don't over tighten, as any clamp indents in the pipe can cause future disassembly nightmares.
Good luck!
 
DougF said:
Don't over tighten, as any clamp indents in the pipe can cause future disassembly nightmares.
Good luck!
Click to expand...

Good advice, Doug. An alternative to standard U-bolt clamps are stainless band clamps (Stainless Specialties - on the web). A U-bolt clamp makes it permanent!
 
Thanks for the great advice everyone!
I have decided to stick with just replacing the original exhaust with the SS one. The header will have to wait until I do engine work, and have more time.
According to Bently I can replace the exhaust system without doing any welding. Is this correct? BTW, I also bought the SS fitting kit.
I assume the header to downpipe can be difficult to remove? Will lots of penetrant help here? or, am I bound to have trouble anyway?
Thank you.
 
Yes and Yes and Yes.
 
:iagree:
But so far I've been lucky, always been able to get them apart after liberal application of PB Blaster (my favorite penetrant, MUCH better than Liquid Wrench or WD 40) plus much cursing and wiggling things back and forth.

DougF's comment about studs is on-target too; I would suggest having new studs on hand as I consider them to be consumables. Reuse the old ones if they are in good shape, but they frequently aren't.

I suggest copper-based antiseize on the threads when you reassemble.

Another option, BTW, might be to just take it to a local muffler shop and say "fix it". For both the Stag and the TR3A, that wound up being a good deal cheaper than just buying the purpose-made parts, let alone the time and frustration of installing them. He supplied "glass pack" mufflers that are superior in construction to the originals ("seamless" welded, rather than rolled seams) and welded the pipes together from bits (leaving slip joints where needed). The TR cost me less than $100 installed with tax (tho that was a few years ago); while the much more complicated Stag was still under $300 in 2005. Of course the price depends on how much he can reuse of the original system; my head and tail pipes were in good shape and just the mufflers were toast.
 
The header is a lot of extra grief for a mixed bag of benefits and problems. (They can expose your alternator and starter to a lot of heat.)I would use the stock header; if you are ambitious take it of and match it to the ports by filing and use of a dremel tool, using a piece of bristol board or the old gasket it it is intact as a guide.

Getting the old system off will require lots of heat and banging with a big hammer; putting the new one on should not be too hard but will take some patience, and is easier with a helper, otherwise you are supporting bits of pipe on cardboard boxes etc. while wiggling other bits into position.
Simon.
 
I have not had success in the realm of headers.

My previous life was Ford products and Mustangs in particular and I found it not to be worth the trouble.

My TR3 and MGA Coupe shall not get headers.

Good luck with decisions.

Cheers.
 
ok,
I just have to jump in on this one since i have spent about 5 years researching tuned exhaust system design. First, A PROPERLY designed AND BUILT header will help make any motor make more power. This is where the problem begins, most are NOT DESIGNED or BUILT to match YOUR exact engine. Most off the shelf headers are for a particular power band but are poorly made. There are two (2) philosophies about header tuning, one is based on the theory of the SOUND wave and the other is based on the theory of mass momentum and pulse. Both are similar but the tuning design is different.
High rpm motors appear to show indications that they work on the mass/pulse however for our low rpm motors that max at about 6000rpm show strong indications that they follow the sound wave theory when used as an interference wave from pairs of cylinders, for us, that is the 6-3-1 header and 4-2-1 header but these NEED equal length primaries to work best. stainless does not make more power but a proper design will. If i owned a tr6 street car, i would only put on a 6-3-1 header that had as close to equal length primaries as possible of about 16"-18" length and between 1 3/8" to 1 1/2" diameter. secondaries about one pipe size. larger diameter but i cannot comment on length for the tr6.
REAL headers that work are not cheap, they fit, and they make power. Most cheap headers are a waste of time and money and you could probably do better by putting on some mufflers that FLOW well, the old Cyclone turbo sonic mufflers come to mind but a good straight though desing may give a better power increase with a loudness penalty. So, a 6-3-1 header into two, through a pair of mufflers would probably be ideal. Any header that requires modifcations and fiddling to get in is C##P! you get what you pay for.
Any headers that i have seen for just about any engine that are any good start well above $500 and up for a 4-cylinder. that's not even stainless. Real v8 headers that really work, start at about $1200 and up.
This is why people have bad experiences with some headers-they are made for looks and for a certain price.
For a tr6, about as close as you can come for an off the shelf header that is any good, is the one by tony lindsay dean, and that one is not perfect.
IMHO
I will save the equal length vs unequal length discussion for another day.
Rob
 
if i recall, the "double-S" mufflers do not flow well. I could be wrong. The original stock mufflers were bad for flow, so if the double-s are the same as stock, and you want some more ponies, don't buy these. I think this is what is used in the "stainless exhaust systems" being sold.
IMHO
Rob
 
me again,
this appears to be an EXCELLENT tr6 header. see web
zeroexhausts.co.uk
i do not know the rpm range it is for though.
Rob
 
Back
Top