Kameari Engine Works - Idler Kit Discussion Split from Brown Hornet Build Thread

[dat2kman]

All the Kameari timing chain tensioner units seem to be a bit noisy.

Sound quite similar to the old Pete Jackson steel gear drives for the old Holden sixes.

 

What brand was that intake mainfold?

[zed74]

All the Kameari timing chain tensioner units seem to be a bit noisy.

Sound quite similar to the old Pete Jackson steel gear drives for the old Holden sixes.

 

What brand was that intake mainfold?

Agree the Kameari timing chain tensioner kit are very noisy (even when your helmet is on!) - but they do the business...probably not refined enough for day to day driving.

 

Simple case of the "wrong manifold" being used with those SWR headers...I have the SWR headers & with a little clearancing the Redline manifold fits up fine (with no modification to the primaries on the headers).

[zed74]

Who fitted the manifold onto the car?

 

It's as rough as guts, I would've thought anyone would know that's a poor way to fit something. I'm sure it they mentioned doing that way to Adam he would've found a way around it or purchase a different manifold that fits properly.

 

Regarding the tensioner, I'll need one of these, how loud are they exactly?

It's a very dominate sound front the engine bay - you know your running one...but it is purposeful like a supercharger type whine

[260DET]

It's a very dominate sound front the engine bay - you know your running one...but it is purposeful like a supercharger type whine

 

Without the supercharger power though 

 

PS Whoever bashed those headers needs surgical attention to his family jewels 

[d3c0y]

Or you could just not deck the crap out of your head and avoid running one...

[HS30-H]

Kameari Engine Works have always warned that their 'Twin Idler' cam chain tensioner is noisier than the stock Nissan arrangement. It's to be expected.

 

Few people realise that the original L20 engine design incorporated a similar principle, and it was changed to the oil-pressure boosted 'foot' tensioner and long rubber-faced guides largely to make it quieter and more refined. 

 

KEW have never claimed that the Twin Idler kit is a power-adder per-se. Anybody who thinks it is should read the instructions again...

[ZED83]

 

Regarding the tensioner, I'll need one of these, how loud are they exactly?

 

Gareth im running these Kameari twin idler gears! Yes they make a sound, but to me the noise isnt that bad. They only get really loud if you over tighten them then it sounds like a hot rod lol ????

[C.A.R.]

There are better places to spend your $ when building an L-series engine, - more headwork, better pistons & rods, etc.

Don't bother buying some fancy idler setup.

 

FWIW the 'US L34' doesn't run one...

[HS30-H]

There are better places to spend your $ when building an L-series engine, - more headwork, better pistons & rods, etc.

Don't bother buying some fancy idler setup.

 

FWIW the 'US L34' doesn't run one...

 

"Fancy"? It's not made out of pink chocolate with bits of glittery sugar sprinkled on it, love.

 

Do I smell a little bit of 'not invented here' syndrome?

 

Plenty of people were cynical and sniffy about the KEW Twin Idler kit when it debuted, especially some of the more - shall we say - entrenched of our American friends. I had a few exchanges with one guy who was under the mistaken impression that it would allow the chain to "twang like a GEEtar string". Apparently it was going to fall to pieces and cause engines to blow. The people coming out with all that at the time are pretty quiet now for some reason. 

 

Good luck trying to persuade people they don't need it, and should spend their hard-earned on something else. As a standalone (pretty much) bolt-on part for a set price you'll have trouble persuading them not to, I think. You might also be wasting your time telling them not to try bolting LHD-specific parts (like TWM inlet manifolds) onto the engines in their RHD 'shells, or "fancy" coloured ignition wires that are probably not as good as what they are replacing. Try telling them that their polished valve covers are a waste of time, and that their chosen wheel and tyre combo will make their car slower and handle worse. They'll ignore you. It's human nature.

 

Unlike a lot of the 'tuning' stuff you can buy for these cars, the KEW Twin Idler had a reason to exist and does what it was designed to do. KEW don't tell anyone that it's something it's not. In my experience, they are honest and decent people. You should save some of your ire and sarcasm for the snake oil sellers who truly deserve it. 

[C.A.R.]

.

[chris240]

Locky, restore your previous comment ! I was just getting the popcorn ready..

[260DET]

So what exactly does the KEW twin idler set do that the standard setup doesn't? From a performance, reliability and durability aspect.

[Riceburner]

Maybe this twin idler talk should be relocated so we don't hijack the build thread...

[dat2kman]

So what exactly does the KEW twin idler set do that the standard setup doesn't? From a performance, reliability and durability aspect.

It eliminates the curved slack side guide, has adjustment up near cam gear, eliminates stock oil tensioner plunger.

Enables shaving of head, up to 4mm in L6, and 3mm in L4

Slight difference to L4 due to dfferent diam threads of bolts where bottom idler bolts on

[gav240z]

Maybe this twin idler talk should be relocated so we don't hijack the build thread...

 

Good idea, split from the Brown Hornet Build Thread here.

http://www.viczcar.com/forum/index.php/topic,4168.msg168444.html#new

and put in the engine section of the forum.

 

Knock yourselves out...

 

FWIW:

http://www.kameariusa.com/l6-twin-idler-gear/

 

The weakness of the L motor is the timing chain tensioner. In a high power engine, the stock timing chain, tensioner, and guide are beyond their limit. 

The cams are upgraded, valve springs are stiffer, and the timing is perfectly tuned but power is still missing.  This is due to the friction caused by the guide, chain tensioner, and the straining timing chain itself. 

To build a strong L series motor, you must start from the fundamentals.  The Twin Idler Gear corrects the weakness by replacing the needle roller bearing and the twin sprocket, to reduce the timing chain friction and stabilizing valve timing.

 

Features

- You do not need the return side chain tensioner or chain guide when using this equipment.

-The head space can be adjusted between 0-4mm so the cam spacer is unnecessary. (L4 is 0-3mm)

Rocker guides are lighter and slimmer and help increase the performance of the motor.

- Reduced friction from the timing chain friction and stabilized valve timing.

- Available Colors:  Red, Blue, Polished.

 

- Machined Chromoly Sprocket

- Duralumin Plate

- Chromoly Slide Plate

 

Anodized Red, Anodized Blue, Polished

 

RPM Tolerance

 

13,000 RPM

[d3c0y]

Alan I don't think that anyone is saying that Kameari or the idler is a bad, it's just that most people don't understand what it's for, as per Jason's spot on explanation above.

 

 

And I think Lurch's comment is justified. If you are building a proper engine, you set it up to have the correct compression ratio without decking the crap out of the head and changing the valve geometry unless of course your class of racing doesn't allow you to do that. My L34 doesn't run one either.

 

 

I don't see why there is any conjecture on this part?

[gav240z]

Does the idler pulley sound anything like this?

 

 

You can hear some kind of idler noise I think on this S20. But I think it might be the straight cut gear driven oil pumps Alan described here.

http://www.gtr.co.uk/forum/236658-1969-nissan-s20-twin-cam-engine-rebuild-3.html#post2470802

[HS30-H]

Alan I don't think that anyone is saying that Kameari or the idler is a bad, it's just that most people don't understand what it's for, as per Jason's spot on explanation above.

 

 

And I think Lurch's comment is justified. If you are building a proper engine, you set it up to have the correct compression ratio without decking the crap out of the head and changing the valve geometry unless of course your class of racing doesn't allow you to do that. My L34 doesn't run one either.

 

 

I don't see why there is any conjecture on this part?

 

As per usual when this product is being discussed, people are talking mainly about one of the side benefits and not the main reason for its creation.

 

I've been through this many times on other forums - in particular HybridZ - so this is Groundhog Day stuff for me, but as KEW don't tend to be invited along when their products are put in front of judge, jury and executioner I guess I'll have to take another stab at defending their creation and try to represent their side of the story.

 

I used to visit Kameari's shop/office/workshop just outside Tokyo a real lot. I first started going there regularly in the late 1990s. Every time I was in Tokyo for work I'd jump on the train and go up there  to buy a few parts, talk a bit, have a coffee and then jump on the train to get back to central Tokyo again for dinner. People would ask me to pick stuff up for them, and I would oblige as it was fun and interesting. I was always well received and we'd often talk about old parts and old times, current parts and future plans. It was around this time that Mori san told me he was developing something that he hoped would help to eliminate a phenomenon that they'd seen often on the engine dyno, and which was causing problems in certain extreme conditions.

 

It was all about timing chain 'whip'; where the relationship between the crankshaft and the camshaft was no longer being controlled by the stock tensioning system and guides. Ideally (as in gear-train cam drives) the camshaft should rotate in a fixed relationship with the rotation of the crankshaft. This is fairly easy to achieve under constant or increasing engine speeds where the crank is 'pulling' the cam to rotate it, but in certain conditions (fast throttle-off, engine braking/deceleration) Mori san and his team noticed that the stock tensioner 'foot' (which is spring-assisted but mainly uses oil-pressure to exert a force on the chain) was being overcome and the chain was pushing the 'foot' back enough for the chain to 'whip' - allowing the relationship between the crank and cam to change. Obviously on interference builds this is not good, and pistons can come into contact with valves...

 

They set up a few tests to see what was happening; One of these involved observing chain behaviour with the aid of a stroboscope. What they saw was a harmonic that could occur in certain conditions, and a 'wave' effect on the chain that looked - as they described to me - like the wave you could send down a skipping rope when you were a kid. In these conditions the stock chain tensioner system was being completely overwhelmed.

 

THAT is the condition which the KEW Twin Idler was created to help overcome. All the other benefits (including the elimination of cam tower shimming on extreme shaved heads) are useful spin-offs that can help to kill two or even three birds with one stone. As it turns out, it's probably a fact that 99% of engines now fitted with the KEW Twin Idler didn't really need one, but so what? How are you going to police that? People will buy bolt-on parts and they will bolt them on. Most of them - as has always been the case with tuning parts - don't know what they are doing, and don't understand what the part is meant to do.

 

A lot of the negativity surrounding the KEW Twin Idler stemmed from people not knowing what it was meant to do. They didn't have any problem with their stock tensioners and didn't suffer any ill effects from chain whip, so why was it created? They latched onto the quote of "13,000 RPM" and took the piss because they thought it referred to crank speed and some kind of promise of higher revs. They believed that it was being sold as a bolt-on power adder, when the maker claimed nothing of the sort. The manner of their criticism often revealed a hidden agenda and - interestingly - poked fun at the product rather than attempting to understand it. So when I see people describing it as "fancy" the old deja vu kicks in again. Personally I don't particularly like blue or red anodised finishes on anything except aircraft plumbing and centre lock wheel nuts, and polished alloy engine componentry doesn't do it for me either, but I realise KEW have to market and actually sell the products they make and that's what appeals to the main part of the market. If that part of "fancy" is what is being objected to then I agree, but it's easily cured and I know of more than one KEW Twin Idler that sits behind a stock inspection cover.

 

I've stuck up for KEW and their Twin Idler for many years now mainly because I saw people who obviously didn't have the faintest clue about it trying to blow it out of the water. I felt like somebody should put across KEW's side of the story for the sake of balance. I've sourced and supplied a lot of them (used on street cars, and race and rally cars that have taken part in national and international events) but guess what? I don't currently own or use one myself.

 

So buy one or don't buy one. Recommend one, or tell people they don't need one (most of the time they probably don't), but please do KEW the courtesy of understanding their product and the condition it was designed to eliminate. Thank you.                 

[HS30-H]

And one more thing. I see no reason whatsoever to buy Kameari Engine Works products from anyone in the USA.

 

I recommend - if you are interested in buying KEW products, and have any doubts/questions - that you deal DIRECT with Kameari in Japan via e-mail (in English) and get the data from the people who understand it. They won't give you the Hard Sell, and they will try to get you to think of your engine as a coordinated and well matched package rather than a random conglomeration of parts. 

 

The (machine translated) quote from the so-called 'kameari usa' website further back in the thread says it all, really.   

[HS30-H]

Does the idler pulley sound anything like this?

 

 

You can hear some kind of idler noise I think on this S20. But I think it might be the straight cut gear driven oil pumps Alan described here.

http://www.gtr.co.uk/forum/236658-1969-nissan-s20-twin-cam-engine-rebuild-3.html#post2470802

 

Gav,

The S20 engine sounds like that anyway (late straight-cut gear driven oil pump type or not) because the cam chain tensioning system design is effectively the same as the KEW Twin Idler: It has two small rubber-faced static guides and two jockey wheels - one of which is manually-adjusted from outside the engine to give the desired tension.

 

In one of Prof. Stephen Hawking's parallel universes there's probably a company making and selling simplified oil-pressure and spring assisted chain tensioner conversion kits for S20 engines because the chain doesn't whip around enough and it's too 'noisy'...

 

 

[Riceburner]

I don't mind that sound at all, it's not noticeable once the revs rise.

 

I'll need to shave the head to get my comp ratio up as I've gone for super light weight flat top Pistons. I didn't want to play with the head anymore by welding it or getting domed Pistons.

 

The KEW twin idler for me will be the simplest solution, it'll allow me to have a light weight long rod bottom end, my PMC P90 head with a 'new' 10.5:1 comp ratio.

 

My understanding was it allowed you to shave the head more than factory spec without having to alter the valve geometry?

 

EDIT: Alan has answered my question above.

 

 

[HS30-H]

.

 

I've seen and heard plenty of people dissing the Twin Idler over the years. Most of the comments wash over me and are easy to ignore because the source is obviously an idiot.

 

But when the barbed criticism comes from someone I have come to respect, it jars. Makes me think there's something else behind it.

 

Loyalty, perhaps? I've had exchanges with PMC Race Engines on HybridZ where Peter implied that the KEW Twin Idler actually cost power. He eventually withdrew the comment, but his reservations are clear. So, you pay your money and you take your choice.

 

The moral is probably that you should go with the Guru of your choice, but don't try to mix parts, data and advice from more than one Guru or you'll end up making a cat's arse out of it all.     

[gav240z]

Thanks Alan, that was very insightful and useful.

 

 

PS: I didn't know you could extrapolate so much information from a simple period character, but there you go. Context is king.

 

 

[dat2kman]

My incar videos you can hear it, but also exhaust and gearbox.

Quite happy at 7800 rpm

 

As said, it sounds just like an old Holden six aftermarket cam gear drive, by Pete Jackson, where they ditched the stock bakelite fibre gear and replaced it with a steel gear.

 

I've suppled a few of the KEW unts to both 6 and 4 cyl cars, mainly race, some rally.

It's very easy to get them out of KEW.

 

Before these were around, the likes of Graham and Stewart Wilkins, Les Collins, Murray Coote, and others had a few little well known tricks to offset mount the curved guide and stock oil tensioner plunger block, and increase spring tension, to reduce the prpensity of slack side chain whip.

This stuff was done 35 years ago here!

[HS30-H]

Before these were around, the likes of Graham and Stewart Wilkins, Les Collins, Murray Coote, and others had a few little well known tricks to offset mount the curved guide and stock oil tensioner plunger block, and increase spring tension, to reduce the prpensity of slack side chain whip.

This stuff was done 35 years ago here!

 

The same tricks that were being used by Nissan's works race engine builders soon after the L-gata engines debuted.

 

There's very little new under the sun in regard to these engines.