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What a great reply! Thanks for the clarification on the measuring.

The manifold is from a BTCC DC5, luckily for me the engines of that era weren't too gnarly. They were on a single throttle body, wet sumped, valve sizes were the same, head was only lightly worked, although they did run mega non vtec cams. Not sure on cr, but they were definitely 2litre.

Do you think a peaky torque curve is such a bad thing? I want the car performing at it's best on circuit.
 

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Arouse the DAMPFHAMMER!
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Conversion into 4-1 system with conical reverse section

What a great reply! Thanks for the clarification on the measuring.
If it helps, it is good :D

The manifold is from a BTCC DC5, luckily for me the engines of that era weren't too gnarly. They were on a single throttle body, wet sumped, valve sizes were the same, head was only lightly worked, although they did run mega non vtec cams. Not sure on cr, but they were definitely 2litre.
Good thing to know :D

...Do you think a peaky torque curve is such a bad thing? I want the car performing at it's best on circuit.
Circuit = TB response and best pretty flat torque curve...depending on the amount of corners, corner radius, length of straits the full header for the upper mentioned engine size and setup you wont love it.

Lower midrange:
You would forced to set VTEC to higher engine speeds because of the bad VE in the lower midrange...once you touch low speed cam in a corner, depending on low speed cam design :scared:...no fun at all :D.

Midrange:
VTEC time :D, torque "explods" as VE rapidly increases (peaky torque)...so the transition from low speed to high speed will be...like Joe sometimes said..."pain in the ass" to tune. VE there will be great!

Higher midrange:
VE decreases quick...responsiveness of engine/car in that area will be not as good as it could be. This will makes the car harder to drive...a very good driver can overcompensate this by anticipating the track and situations with other racers :D

High end:
VE still decreases, but now more quick...car wont pull hard there as it is a bit choke-like there...there will be the character of that header be most significant concerning your application...the shorter the straights, the harder the corners, the better with that header...but in the end...


...I believe, converting it into a 4 to 1 system would give you the best of all. What about validating my above mentioned hypothesis by:
  • firstly, tuning it with the actual 4-2-1 header layout
  • secondly tuning it as an 4-1 header system with an 3" adapter to the rest of the exhaust
you will save the money anyway to buy another one, just buy an adapter pipe and a Hytech or Burns 4-1 merger...maybe with a conical reversed section to compensate the adapter.

Another :twocents:
 

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I see what you're saying.. Running back to back tuning sessions would require a lot of outlay in dyno time, and exhaust fabrication. As much as I want to know what set up will work 'best', I don't have factory support. ;)

I like the idea of installing a 4-1 collector, do you think the primaries will 'work' with such a set up?

I need to have another look at the 2-1 collectors in my hand, it might be possible to modify them into an efficient 4-1 collector. I don't like waste, and it leaves more money for fuel, tyres and brakes. ;)

Thanks for the great info, I had a feeling this thread would be the right place for my first post.

Out of interest, i searched for k20 swapped lotus manifolds, to see what solutions they have, and they seem to have longer primaries than our 'off the shelf' fwd manifolds. You mentioned k20's liking short primaries, why do you think the k20 swapped cars would have longer primaries?
 

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Arouse the DAMPFHAMMER!
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Good question...

...Running back to back tuning sessions would require a lot of outlay in dyno time, and exhaust fabrication. As much as I want to know what set up will work 'best', I don't have factory support.
Understood.

I like the idea of installing a 4-1 collector, do you think the primaries will 'work' with such a set up?
They are a better compromise for the are beyond 6.5 krpm, as they better the VE production compared to your existing 4-2-1 setup.

...it might be possible to modify them into an efficient 4-1 collector. I don't like waste...
I wouldn't do that, once it goes wrong you would have to buy a merger anyway. If you don't want to invest there, just keep it as it is...in case the header is already plug and play for your chassis :D.

...i searched for k20 swapped lotus manifolds, to see what solutions they have, and they seem to have longer primaries than our 'off the shelf' fwd manifolds. You mentioned k20's liking short primaries, why do you think the k20 swapped cars would have longer primaries?
Findings of the market is like picking up flowers :D...you will get every color and style. The lotus has a specific clearance situation, leading, due to the complex cornering of pipes around the rear chassis bar (above it or below through it) to a bit more clearance forced designs. My actual header is a 4-1 system with Ø46-350 mm primaries...btw too short...fill up the room below the compartement completely with header, CAT, corner pipe and muffler...which has a completely clearance forced design.

But you are right, there are long primaries designs like

Source: Hondaelise.com


Source: origin HyTech header listed at lotustalk.com

But those are just results of bends and good midrange power as the most K20 swaps in Lotus' are very mild builds...no need for big power once the cerb weight is below 750 kg and hang just 400 mm above the street, to show the big guys what is a real good circuit time :D

The best header design...not available any more:

Source: Dereck from Hondata at photopucket.com

This is Joe's design, this is just a love story for the K-series engine in terms of fabrication quality, thermodynamical and flow mechanic design...of course there is some potential left to optimize it :D...but I never saw something better like that in a Lotus.
 

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The best header design...not available any more:

Source: Dereck from Hondata at photopucket.com

This is Joe's design, this is just a love story for the K-series engine in terms of fabrication quality, thermodynamical and flow mechanic design...of course there is some potential left to optimize it :D...but I never saw something better like that in a Lotus.
Do you know how long the primary's are on the above manifold?
 

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May you ask Jackson Racing to bring their header back

Do you know how long the primary's are on the above manifold?
Any luck on the dimensions of the above manifold?...
Hi M111 and AvGas, I didn't get the data of Joe's manifold. But Joe shared the diameters in that thread - go through it, it is valuable to read :D - and did hints about the length measurements. There are some guys, they got some data of Joe, but I never saw a Joe like header again...it's not only about the dimensions, it's about the shape, pipe routing and fab quality.

What I can say is, the header total pipe length is relatively short compared to the market, I know only one header which was comparable with that type of right - in terms of VE supporting scavenging power and engine speed - placed header, it is the Jackson racing 05' or 06' header of the 03' Civic Si. A bit shorter primaries than Joe's one, but similar secondary length. In terms of VE barycenter, those two headers differ not that much...as both have their Achilles' heel below 5 krpm :D.


Source: http://www.ephatch.com/forum/showthread.php?67556-Ep3-Header-Options-101-(Pics-included)

Look away for some lines, Joe :D! These piece of cake in terms of high engine speed VE production was a blast in terms of power, piked up around 15 whp and supported VE beyond 5 krpm...fab quality was lower, but it did it's job also like Joe's :D. I don't know the origin where Jackson racing sorced it, but a question takes just some minutes :D.

Markus
 

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."The same thing holds true for my divorced cam oiling setup. I invented it and then idiots who don't even understand how it works start making bad copies of it."
So, has anyone started doing it in the manner that Joe did?

I know Tractuff and Hytech are still doing it in a manner that Joe found suboptimal.
 

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I know Tractuff and Hytech are still doing it in a manner that Joe found suboptimal.
There are some copies running here in Europe, but done individually by the users itself with some dimensional modifications compared to Joe's. Joe's header design is good for highest peak power output. It works pretty good in combination with his IM design, which helps a lot to support this. As long as you haven't his IM there is a good reason for other designs to have an increased torque bandwitdh down low too.
 

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There are some copies running here in Europe, but done individually by the users itself with some dimensional modifications compared to Joe's. Joe's header design is good for highest peak power output. It works pretty good in combination with his IM design, which helps a lot to support this. As long as you haven't his IM there is a good reason for other designs to have an increased torque bandwitdh down low too.
Ah, sorry for the miscommunication Lotus. I'm more curious on how he performed the 5th cam tower modification for external oiling. Joe's method seems to lead to a greater reduction in weight (in that he didn't need to plug the rocker shaft with his method), and I think maybe he had more material removed? #addlightness

Quote from Joe,

"If done properly the No.5 cam saddle can be machined to provide the cams with constant full volume full pressure oiling without having to plug off the rear of the rocker shafts, this is something I pioneered quite some time ago."

Per SVMCams,

"Allow me to disagree as I am currently doing these per joes instructions and yes he was highly critical of the tractuff mod.

From my understanding joe's method routes the oil by creating a path between the 2 bearing journals on #5.

Hytech method comes under the bearing area and shoots the oil upwards.

Does this make sense? Also #2 is modified per Joe Mac method. This mod takes the psi when the engine is NOT on VTEC from 4-7 all the way to engine oil psi... Around 80psi. Also increases oil flow 3 times more than usual."
 

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Ah, sorry for the miscommunication Lotus. I'm more curious on how he performed the 5th cam tower modification for external oiling. Joe's method seems to lead to a greater reduction in weight (in that he didn't need to plug the rocker shaft with his method), and I think maybe he had more material removed?
Oh, I missed your posted quote to read. I am sorry for that.

From my perspective another question beside the possible better oil performance is relevant. I was just tuning my own car last week and several screws got loose, just because of the vibration introduced by shifting, knocking, normal engine operation and fuel cut situations. When doing a 5th cam tower oiling, you always have to feed the 5th cam tower by moving the oil from a pressure source to the cam tower at cylinder #4. Joe did it with swage lock connectors and stainless steal pipings. My question is, is such a system brake safe enough against the typical vibration amplitude and frequency. Or is a customer without knowhow and tools in measuring vibrations on components and interpreting it safe to rule if the system can stand all what will come? I know a 5th cam tower mod, which broke and the user lost the engine healthyness.

This leads me to the main question. Is it really necessary? And when is it necessary? Joe's argument for it was bigger lift cams, when spring forces and duration of load on the cams increases, than the oil film may can be insufficient. I use only TODA cams, which have a lift of 13 mm at max and may a bit higher spring forces compared to the stock one. There were no reported issues with the OEM style oiling. I see the arguments for the tower modification, but I see no need for it, just a risk of loosing oil pressure rapidly when the piping of it brakes.
 

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Oh, I missed your posted quote to read. I am sorry for that.

From my perspective another question beside the possible better oil performance is relevant. I was just tuning my own car last week and several screws got loose, just because of the vibration introduced by shifting, knocking, normal engine operation and fuel cut situations. When doing a 5th cam tower oiling, you always have to feed the 5th cam tower by moving the oil from a pressure source to the cam tower at cylinder #4. Joe did it with swage lock connectors and stainless steal pipings. My question is, is such a system brake safe enough against the typical vibration amplitude and frequency. Or is a customer without knowhow and tools in measuring vibrations on components and interpreting it safe to rule if the system can stand all what will come? I know a 5th cam tower mod, which broke and the user lost the engine healthyness.

This leads me to the main question. Is it really necessary? And when is it necessary? Joe's argument for it was bigger lift cams, when spring forces and duration of load on the cams increases, than the oil film may can be insufficient. I use only TODA cams, which have a lift of 13 mm at max and may a bit higher spring forces compared to the stock one. There were no reported issues with the OEM style oiling. I see the arguments for the tower modification, but I see no need for it, just a risk of loosing oil pressure rapidly when the piping of it brakes.
No need for apologies, life happens.

I've expanded my motor experience into BMW's, and noted that they had external hardline(s) on the engine... so I wouldn't say that the selected materials are "wrong" or inherently unreliable. Proper fitting selection, torque, and thread locker/sealants should provide OEM-level reliability. I'm not particularly worried about the fittings to be honest, but each person has their own. (I had also used Tractuff's service on my cam tower. Likely completely placebo, I think the valvetrain was quieter/happier... but I didn't have an A-B-A comparison or anything to substantiate that.)

Is it necessary? No, it is not necessary. Is it potentially longevity enhancing? I would believe so. Low oil pressure/supply to the cam caps is likely not conducive to a long service life, especially when uprating cams, springs, and rpms.

If we're looking at what could be lost via "superfluous" items... sometimes complexity is worth it.

I don't have the requisite machining experience nor the tools to make it happen... but if we can get in-depth description of the modifications maybe someone else can resurrect this alternative way of accomplishing this. Found a picture that was previously posted, and I'll attach it for the sake of concentrating all of Joe's stuff.
101362
5th cam tower mod joe mac.jpg
 
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