khezz

Will do. Thank you.

Do I just stay with my 260/10.25 and see how they go?

Wow. Did not even think about either of the points (metal quality, lift at various duration). Fair call on both points. I've never had issues with tomei before but never used anything else either. I have always read that duration is for top end power and lift is for midrange torque. Might have to do some more reading. Problem I find is most of the 1000hp+ cars won't list am specs. I don't know why. I would have thought info sharing makes for easier product development.

Hell Yeah!!! That's why I'm spending my kids school funds 🤑

I had a look at kelford but there specs seem to be more fo high revving engines and not a huge amount of lift. To go over 11mm lift I need to go to 288 duration. If I was revving my engine to 9500+ or using it purely for racing, that would be ok. I've used 2 sets of tomei cams before and never had an issue. Jun was another consideration with 280/11.65 but can't find many reviews on them.

Going to be ordering a new set of camshafts. Goingbwith Tomei 280/11.5 on both sides. I am not planning on revving the car past 8500rpm so I don't need any more duration and they are the highest should help with spool mid range. Happy to take on any advice people may have.

Fair call. Was thinking of staying with the smaller 1.12 T4 devided. Sounds like the way to go.

What size/type exhaust housing would be recommended for my application. Stick with devided T4 1.12 or 1.28 Or maybe try Vband 1.15 or 1.28

Me to mate. Thank you

Looking at the Coota records, it seems that OS88 started falling away about 3 years ago. As with all things, better products came on the market. Some still use them and have been using them for years. Mercury R34 held the coota record for years with that box and lived a very hard life very reliably. I really appreciate all the advice. It was the right choice for me. I am not forking out 12-13k for a 20+ year old getrag and the going through the pain of the conversion which will cost thousands more. PPG dog boxes have also gone up in price alot with no real improvement in the product. OS gearsets have a very sketchy reputation and PAR don't seem to do 5 speed anymore. Plus I could not find any cars of similar power running their gears.

Well the way I looked at it is ppg, samsonas 6xd are all around $24k just to buy. Plus clutch so there is another $3k. Ppg I think charge $500 to fit the internals into my case. But there is transit cost from West to East and back again so there is another $600. I have no idea what's involved in fitting a samsonas but let's say it's easy and I'm up for another $500. I am up to $28k to $29k. For $8k to $9k less I can have the OS88 installed with flatshift and it will do the job just fine. It may not be is refined as the others but it will be so much better then the original 5 speed. The change I have left can go towards a very nice interior upgrade.

Well there you go.

Yeah it seems like the only legit twin setup is the G25-660s. Unless some tries a custom precision setup 5558 or 6062. Sad that twins are pretty much dead for now. Just something about seeing snails full of blades ready to scream under the bonnet. Oh well. Maybe I'll go a billet RB36 with twin 6466s. 🤘

So I am not using clutch less shift and depress throttle between shifts I won't need it? I will get one, I am just trying to learn.

Pardon my ignorance but what is the gear position sensor for? Is this part of the requirement for flat shifting?

Got the os88 with new os quad plate for 17500.

Thanks for your help fellas. Ended up going with OS88. Came down to price plus the 6th gear. It will handle what I want it to do.

So I am waiting for an invoice for an OS88 gearbox and OS quad plate clutch. I know the plan was to go for dog box but I just couldn't say no. Does any one know if shift cut can be easily installed after the gearbox has been installed or should I try and do it now?

I wonder if in another 5 or so years 1000hp will be possible with a basic head freshen up, gasket, studs and the right hot/cold/fuel combo. What a time to be alive

Im blown away. Would love to see the dyno graph. Whats the rest of your setup? I still have all my old HPI and Zoom magazines. I should repost the builders guide to rb26 from HPI magazine. There it says that 400kw is stage 5 and is only for the serious builder with a huge budget. How times have changed. I guess that's why with porting, most workshops now say go all out or don't touch it at all.

Nice. That's some kick after 4000rpm. My lowmounts did thsame but with 200hp less at top. Are you going to keep it stock and see where you end up or do you have further build plans?

Well you would take the diameter of the inlet valve minus the area of the valve stem. There would be an absolute maximum volume that can pass through that area in CFM. Times that by 12 and then use that number to work out what is the maximum number in hp that that flow can provide on e85 or 98ron. I don't care about either number. If diameter didn't matter, why do people go for bigger turbos, injectors, exhaust. Everything has its limits. I just want to know what people have actually achieved. Like Andrew from Motive and Hypergear above.

Nice. So no cams? What's it drive like? Do you have any dyno graphs?

There will be a limit. It would be easy enough to work out just by max air flow through ports but that's the absolute best case scenario which never happens in real world. I have always thought that standard intake manifold is no good over 700hp. In one of the latest motive Cootamundra videos there is an R32 running a standard manifold with well over 1000hp. It will be good to know what people have managed to do.

Thats about the highest that I've heard.