Maniflow exhaust manifold - any good?

[KiwiTR6]

My discussions with Rimmers are ongoing re the poor fitting headers they supplied. They've offered to refund the purchase price and pay for shipping back to the UK - I'm now awaiting their response re who's paying for my original shipping cost.

 

In the meantime I've been looking around for an alternative to match my late model twin pipe exhaust system and came across this:

 

http://www.maniflow.co.uk/index.php?view=product&from=204&product=1513

 

Admittedly they're made from mild steel rather than stainless, but has anyone had any experience with this product or comments related to quality and fit?

 

Gavin

[YankeeTR5]

I think in the grand debate about exhaust headers for the 2.5L, my preference would be either a stock manifold or a 6-3-1 design both of which take into account "resonance exhaust theory" in their design, generally offering a better torque curve and, if all claims are to be believed in the case of the 6-3-1 some instant HP. This appears to be a 6-2-1 design which comes with some tradeoffs, is more of an old school (60's) racing design where flow at top end is sacrosanct, and is often associated with a loss in low end torque. I'm no expert, but this is what I've gleaned from doing research on this. As to the design of this one, others can comment as well. Best of luck with your choice - let us know what you think if you go this way.

[Graham]

Gavin if you do a forum search you will find a lot of discussion on this matter, but I believe the current preference is to go 6-3-1, rather than 6-2-1, as Yankee TR5 suggests, from my trawling of the web that leaves you with the Phoenix/Rimmer one that you currently have, Racestorations, TR enterprises (both mild steel requiring an overhead throttle linkage) or finally one from Good Parts but as was pointed out to me would probably only fit a LHD car. I know there was another U`s manufacturer but believe that are no longer producing their model and again not built for RHD car.

 

anybody know of any others ?

Edited May 1, 2017 by Graham

[astontr6]

Hi Gavin,

 

Glad to see that you are making progress with Rimmer even if it is a bit slow? I know the name Maniflow from the 1960s! I thought that they were long gone! They were well known in Mini circles for exhausts and BMC A & B Engines..

I have an SAH Exhaust Manifold of a similar design, which is made from M/S but the tubing is made from a high grade nickel/chrome content M/S. It has lasted over 40+ years! That is the question that I would ask Maniflow what spec. steel tubing do they use? and go from there? If it is high grade that will answer part of your question.

When I was at the Silverstone Classic last year and in the Pits, I did notice that all the racing engines that I looked at did have M/S tubing for their exhaust manifolds! I know that most racers prefer M/S to S/S because of radiated/heat transfer problems associated with S/S.

 

Bruce.

[Alec Pringle]

Hi Gavin,

 

Maniflow are relatively local to me, I've seen plenty of their competition exhaust work over the years. All the stuff I've seen has been a proper job, as in up to a standard rather than down to a price. Never dealt with them myself though - the couple of occasions I was looking for one-off custom systems their estimates were way too high for my liking.

 

I wouldn't touch a stainless manifold if I had the option of a good mild steel system - no contest, the latter does a better job.

 

I'd still question the value for money factor of shipping a manifold to New Zealand though, unless the engine is very highly tuned the potential benefit/gain in power and torque over the standard cast item is pretty modest. That was my experience of testing a variety of TR5/TR6 manifolds on engine and chassis dynos and test track back in the day, and the run of the mill designs haven't evolved much since then . . . . .

 

Cheers

 

Alec

Edited May 1, 2017 by Alec Pringle

[Tom Fremont]

Hi Gavin,

 

I've got a Racetorations 6-2-1 on my driver with P.I. cam and Weber DCOEs, now with 80K miles on it and a complete success delivering the goods across the rpm range. This is a stainless system which I had ceramic coated.

 

With a much more extreme cam ( .502" lift and 292 deg. duration ) on my concourse car with the same manifold I was never able to get satisfaction in the mid-range, trying countless calibration recipes on the carbs. I finally fit the GOODPARTS mild steel 6-3-1 unit and picked up the slack in the mid-range. Top end is the same, but it was necessary to lean out the main jet system ( 1 fuel and 7 air steps! ) to recover it. Richard Good claims both the primary and secondary runners are equal in length, something the stainless 6-3-1 systems I've seen don't manage to do. Since it's a concourse car I was reluctant to go with a sure-to-rust mild steel manifold and asked him to quote a stainless one at a premium. His answer was " I am unable to build it in stainless." I chose the black ceramic coating ( 1800 deg F ) for easy touch-up when the time comes.

 

Not to belabor the obvious, but the 6-3-1 style pairs the cylinders which are 180 degrees out of phase. So when one is done pushing its mate comes in right behind it.

 

Cheers,

Tom

Edited May 1, 2017 by Tom Fremont

[KiwiTR6]

Thanks everyone for your comments, but as Alec notes they are on the pricey side.

 

I should also clarify that the reason I'm wanting to fit a tubular manifold system to my car is for the sound factor only - my engine is bog standard (well apart from the CP camshaft that is) and if I were looking for performance gains then I'd be taking into account all of the above advice and more re the best option for that purpose.

 

So with that in mind, I'll put my flak jacket on invite comments about the Pacesetter headers. These appear to be relatively inexpensive to get to NZ, and come with an adapter for the later twin pipe system.

 

http://www.ebay.com/itm/282227875603?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

 

However, it appears that these are manufactured for the LHD carbed US model and Pacesetter are unable to tell me if they will fit the RHD injected models.

 

I've managed to find some comments on-line about the product generally, but as usual opinion covers the full spectrum.

 

Gavin

[oldtuckunder]

Well as all your after is a nice noise and the standard manifold isn't that bad, why not just take the car to a good performance exhaust centre and get them to make you a stainless system "tuned" to the noise you want, as if you only change the manifold you are probably going to find that you end up having to change the exhaust anyway to release those decibels anyway.

 

Alan

[kiwican]

I have had pacesetters on my car for the last 25 yrs, pi rhd. I did not have any issues fitting them that i remember.

 

Simon

[BlueTR3A-5EKT]

Here is an even cheaper one!!!

 

http://www.ebay.com/itm/Black-Coated-Performance-Exhaust-Header-Manifold-Kit-73-75-Triumph-TR6-TR-6-2-5L/182390941633?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D2%26asc%3D40130%26meid%3D6851d462c1374092ae32b66d408d9855%26pid%3D100005%26rk%3D3%26rkt%3D4%26mehot%3Dlo%26sd%3D171389592127

 

Challenges will be:-

1. will it miss the RH drive steering column?

2. Will it give clearance for the PI underslung throttle mechanism?

3. Will it fit?

 

As Alec states - stay with the standard item, it gives a fair performance with a regular 150 PI cam.

 

Peter W

PS Maniflow were a supplier to Triumph Tune pre Moss days.

[Alec Pringle]

Sound factor ?

 

Use the standard manifold and a straight-through 'sports' exhaust system, that will give you all the sound you need . . . . . a bunch of bananas won't make much difference, standard or 'sports' system exhaust . . . .

 

Cheers

 

Alec

[Tom Fremont]

I was surprised at the difference in sound produced between 6-2-1 and 6-3-1 systems, the latter sounding like a modern 4 cylinder ( think Honda Civic with coffee can exhaust ).

 

http://vid400.photobucket.com/albums/pp84/ima68tr/Sound%20Effects_zpsgrpuwuxj.mp4

 

Considerably more noise issues from any of these tubular manifolds than from the cast iron ones.

 

Cheers,

Tom

[BlueTR3A-5EKT]

You want noise?

Fit one of these.....

http://forum.mazda6club.com/attachments/3-0l-v6/61966d1194461960-manual-exhaust-bypass-valve-1484_4lo.jpg

 

Also available in electric control version.

http://www.ebay.co.uk/itm/2-5-inch-Exhaust-Bypass-Valve-electric-stainless-cut-out-y-pipe-remote-switch-/232269665651?hash=item361459d573:g:C28AAOSwTuJYxr0v

 

Peter W

Edited May 6, 2017 by BlueTR3A-5EKT

[KiwiTR6]

Well as all your after is a nice noise and the standard manifold isn't that bad, why not just take the car to a good performance exhaust centre and get them to make you a stainless system "tuned" to the noise you want, as if you only change the manifold you are probably going to find that you end up having to change the exhaust anyway to release those decibels anyway.

 

Alan

 

Alan

 

The car already has a new full stainless system so I'm not planning to make any changes there. If I'm not happy with the tubular manifold I'll revert to the standard manifold.

 

Gavin

[KiwiTR6]

I have had pacesetters on my car for the last 25 yrs, pi rhd. I did not have any issues fitting them that i remember.

 

Simon

 

Thanks Simon, that's the sort of info I was hoping for. If Rimmer's can't supply me a decent set then this is likely the way I'll go.

 

Gavin

[KiwiTR6]

Here is an even cheaper one!!!

 

http://www.ebay.com/itm/Black-Coated-Performance-Exhaust-Header-Manifold-Kit-73-75-Triumph-TR6-TR-6-2-5L/182390941633?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D2%26asc%3D40130%26meid%3D6851d462c1374092ae32b66d408d9855%26pid%3D100005%26rk%3D3%26rkt%3D4%26mehot%3Dlo%26sd%3D171389592127

 

Challenges will be:-

1. will it miss the RH drive steering column?

2. Will it give clearance for the PI underslung throttle mechanism?

3. Will it fit?

 

As Alec states - stay with the standard item, it gives a fair performance with a regular 150 PI cam.

 

Peter W

PS Maniflow were a supplier to Triumph Tune pre Moss days.

 

Peter,

 

The item may be cheaper but they claw back the discount and more with their freight charges. A common trick on eBay which may have led to eBay creating their global shipping programme?

 

Gavin

[Mike C]

 

Peter,

 

The item may be cheaper but they claw back the discount and more with their freight charges. A common trick on eBay which may have led to eBay creating their global shipping programme?

 

Gavin

 

​I can agree with that. Looking to purchase a metering unit fuel diaphragm recently, Rimmers and Revington both quoted about 50 pounds to courier it to Australia. I settled for Royal Mail airmail at 4.30 pounds.

[KiwiTR6]

Here is an even cheaper one!!!

 

http://www.ebay.com/itm/Black-Coated-Performance-Exhaust-Header-Manifold-Kit-73-75-Triumph-TR6-TR-6-2-5L/182390941633?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D2%26asc%3D40130%26meid%3D6851d462c1374092ae32b66d408d9855%26pid%3D100005%26rk%3D3%26rkt%3D4%26mehot%3Dlo%26sd%3D171389592127

 

Challenges will be:-

1. will it miss the RH drive steering column?

2. Will it give clearance for the PI underslung throttle mechanism?

3. Will it fit?

 

As Alec states - stay with the standard item, it gives a fair performance with a regular 150 PI cam.

 

Peter W

PS Maniflow were a supplier to Triumph Tune pre Moss days.

 

Just a warning to anyone looking at these headers - I'm sure they aren't Pacesetter!

 

If you look closely you'll see the flange is one piece, not two, and is also a different shape to that of the Pacesetter.

 

It appears to be a Chinese copy, so please beware

 

Gavin

[sixtynine]

I agree with Alec.

Go with stock single. I did.

Maybe with a phoenix big bore intermediate pipe and silencer.

Sounds good and not very loud.

Have to have a 2 1/4" downpipe made up though.

Definitely not anything dual exhaust.

[sixtynine]

I've had 3 sets of headers on these cars over the years. None of the 3 were that good a fit.

I think i had to notch the frame each time.

Also the nuts were a bitch to get to.

[oldtuckunder]

Just smash them around to make them fit, doesn't matter at all

 

https://www.youtube.com/watch?v=azPKIjxmmdU

 

 

Alan

[KiwiTR6]

Really interesting test, but I can't believe they bashed the headers in place without softening the tubes with gas first or taking them off. It was incredibly painful to watch...

[Bodiam]

That looks quite reminiscent of the tubular manifold fitted on my CR when I bought it - it had been attacked in a number of places, with a ball pein hammer I would guess, to clear the bulkhead and other pinch points.

 

I donated it to our local scrappie and fitted a standard cast manifold, which looks very nice with its aluminium sprayed finish and works fine.

 

John