Difference Between Straight Cut And Hellical

[Nizzzm0]

Hi i just want to know the difference between these 2 and do brand names make a difference i looked and i seen the three main brands os giken par and ppg they are all roughly same pricing for gtr are they all same quality?

[R31Nismoid]

Yes brand names do make a difference... One of the 3 you've mentioned has had many issues far and above what you'd call "normal".

Have a google - you'll soon work out which. Each have it's pro's and cons. Different gear ratio options and so on.

I'd suggest you do some research here on SAU and again, more google. There is more then enough information on this very forum alone to give you plenty to think about.

[GTRAAH]

I notice Par not having a great name, there has to be people out there that actually have a par set and are happy with it.

[GTRsean]

Annnnd silence........crickets.

Go os giken.

[turboedsloth]

I notice Par not having a great name, there has to be people out there that actually have a par set and are happy with it.

I don't think PAR like using PAR gearsets

As above, go OS GIKEN

As for differences between straight cut and helical. Straight cut is stronger, but noisy. Whereas helical is like a standard gearset

[The Dan]

And in addition to that:

The reason straight cut is stronger VS helical cut is because the two gears aren't trying to twist off each other. The only reason helical cut gears were developed was to reduce noise.

There is absolutely nothing wrong with PAR gearsets. From the reading I did when they were supposedly having problems, it was dog engagement gearboxes that were having the problem and I can tell you now, dog engagement needs to be driven VERY SPECIFICALLY so make sure you are aware of this if you choose this path.

The options are:

Helical synchro

Helical dog

Straight synchro

Straight dog

Obviously the sets with synchromesh are nicer to drive. Dog engagement should be considered race only and if driven too 'nicely' you will f**k them very quickly

P.s. The gearset picture on top is straight dog. You can see the dog selectors which are like large castle sections which lock in together

[Birds]

From memory of dealing with custom gearset manufacturers, you can also fit wider straight cut gears in a housing than you can helical cut.

[Tai1or Made]

From memory of dealing with custom Hearst manufacturers, you can also fit wider straight cut gears in a housing than you can helical cut.

This is only relevant if it's a dog box (my understanding).

[GTSBoy]

Yuh, dogs take up less room than synchros, and so you get more room for primary gears.

But seeing as it is the dogs (or the teeth in the synchros) that actually transmit the load......

[Birds]

This is only relevant if it's a dog box (my understanding).

Ahhh that's what I was trying to think of. This was the reason why most big HP straight cut gearsets are dog engagement.

That meant to say gearset too, not "Hearst" lol.

[NYTSKY]

There is absolutely nothing wrong with PAR gearsets.

Gears no, dog rings and teeth yes.

[NYTSKY]

I notice Par not having a great name, there has to be people out there that actually have a par set and are happy with it.

Everyone I know with PAR boxes have had dramas.

[GTRAAH]

How strange is that, people who try to say that nothing is wrong with par ... Like look at the above comment... I just cannot believe it NOT 1 person can say they have a PAR and its great NOT 1 how can they be a good brand if this is the case?

[GTRAAH]

Ok How about this one, PAR Straight Cut VS OS Giken Helical?

What would be the stronger set?

[The Dan]

Yeah I know a lot of people have had dramas but what I heard was the dramas were to do with the way they were being driven which caused premature wear of the dog teeth.

I cannot personally comment on their quality as I have never used a set from PAR but TBH how could they still be in business if they had a shit product. I can tell you for certain that if they are driven gently, they will be wrecked in no time. I spoke with PAR a while back about it when we were looking for solutions to breakages and they told me that was the very reason they were having problems - that and workshops fitting them that didn't know what they were doing.

NYTSKY - did your firends have the PAR sets installed by PAR? or were they fitted by someone else?

[The Dan]

You cannot really go wrong with OS GIken, though. No bad reports. Holds tonnes of HP.

I'm pretty sure the choice is simple

[GTRAAH]

So even tho straight cut is stronger, A helical OS Giken would be the choice. That equals WOW.... They must be really bad in that case as a straight cut is roughly 35% stronger then a helical. So if an Os GIKEN helical is stronger then a Straight cut PAR, then basically a helical PAR would be around 70% weaker then a Helical OS Giken. LOL

[Piggaz]

You cannot really go wrong with OS GIken, though. No bad reports. Holds tonnes of HP.

I'm pretty sure the choice is simple

+1. I own one and it's great. The tall first is a cool thing too, although I'd say you'd really need a stroker to get the most of out this box. The tall gear's can work against you on a 'peaky curve' car.

[Nee-san]

So even tho straight cut is stronger, A helical OS Giken would be the choice. That equals WOW.... They must be really bad in that case as a straight cut is roughly 35% stronger then a helical. So if an Os GIKEN helical is stronger then a Straight cut PAR, then basically a helical PAR would be around 70% weaker then a Helical OS Giken. LOL

It isn't that straight cut (haha get it ?) you can't really say they are ~30% stronger, there are upsides to helical gearsets other than reduced noise. for example a helical gearface actually has a greater meshing contact area to distribute forces more evenly (we are speaking relatively about the gear sizes themselves obviously) helical gearsets are also more robust when you're considering axial loading.

[33GTRV]

i have a par gearset, actually, ive had 7 of them.......and to be honest, its still going through small claims after over 12 months. The gearset in question was a syncro set, and as far as im concerned, i will never reccomend them, nor use them, i would not even use the gearset to put out gerrard if he was on fire. It has cost considerable money, time and i have ZERO patience left. I highly reccomend going an OS set or the PPG set.

For more information regarding the issues feel free to PM me.