Equal length headers?

[mole42]

Has anyone managed to make a pair of exhaust manifolds for the Stag V8 with equal length headers?

[new to this]

Theres not enough room you would have to cut the strut tower , even then not sure

[flying farmer]

Best I have managed is equal length 4:2:1 on my 256bhp mk1. Not easy to make, there are some pictures of the front half on my Flying Farmers new project thread, page 25 I think.

I am attempting to build an 8 into one header for the TR, supposedly the ultimate for power and torque. Not even sure I can squeeze it all in, and it certainly won't fit into a Stag because the collector is 6 inches across. I can easily move the radiator forward a couple of inches on the TR to make room. This will be a Winter project as I want to strip the car for a respray, though I have already started work on the manifold.

Neil

[Chris01573]

I saw a pair of forward facing headers on fb today

[mole42]

I think 4:2:1 is all that might be possible, and cross-plane cranks aren’t supposed to benefit from equal-length headers so maybe it’s a hiding to nothing…..

[mike@thenook]

I saw a pair of forward facing headers on fb today

They were the original type before Monarch designed the ones which Phoenix now make.. They are fine if you move the alternator and don't have a Steve Hill water pump like I do,

[jbuckl]

Do the Phoenix ones allow for LH alternator and Steve hill pump?

[DJT]

Do the Phoenix ones allow for LH alternator and Steve hill pump?

Yes, I have that setup with a standard 18ACR alternator and a home made alternator bracket to Steve Hill's design.

[mike@thenook]

Do the Phoenix ones allow for LH alternator and Steve hill pump?

Yes, I have this set up but with a higher output alternator and an EJ Ward bracket plus Steve's pump mod..

[Philip Wardle]

I'm not sure whether this info helps, but some years ago now a SOC member fabricated three sets of prototype manifolds and bracket to relocate the alternator as per the attached photos (I've not bothered to upload the downpipe extensions). Three of us bought a set, mine is still in shed no. 2 and I may not get round to fitting them on the current or future Stag. I do know that at least one set has been successfully installed, though I believe some minor fettling was needed to welds on the inside of the ports, which isn't as good as the visible welds on the outside. I seem to remember that at least one pipe to the power steering pump needed to be modified.

[Lingen]

Phil.
And if/when you do fit them, how many extra "Horses" are you expecting to find?
Mike.

[Philip Wardle]

Not sure Mike, though I woudn't be surprised to learn that someone who has fitted tublular manifolds has measured an improvement - it would be inreresting to know how different arrangements compare.

[flying farmer]

Some years ago I asked people who had done rolling road tests to post their results, I don’t think there was a single before and after. What I did notice is that most standard Stags were about 7-10 bhp down on the factory figures, whereas the ones with tubular manifolds were nearer the factory figures

[flying farmer]

Search for the thread performance tuning the Stag engine. All the information is in there in the first few pages. I am out of the country at the moment and only have my phone, so the graphs are unreadable on the small screen

[alan_thomas]

Some years ago I asked people who had done rolling road tests to post their results, I donât think there was a single before and after. What I did notice is that most standard Stags were about 7-10 bhp down on the factory figures, whereas the ones with tubular manifolds were nearer the factory figures

Few, if any, have experimented more than you Neil, what’s your gut feel . Is the original design more inlet restricted or exhaust restricted ? Does improving the exhaust simply hit the inlet capability, or the other way around?
Alan