pcmhacking.net

Just in the process of picking a rather uncommon NOS set of borg 3.73 diff gears for not a bad price of $600. Some guy had them on a NOS group I'm on fb and happen to be the ratio I was looking for.

I have all my drive line ratios/specs worked out and tyre sizes based on what's available for 16" walky rims.

gears for the t5 will be the PPG saloon gear set. It sure has a much better spread than stock that's for sure.

Btw does anyone know of any mechanical roller lifters with fully shrouded roller than works with v6? All of the ones I'm finding are uncovered and I have no idea how they would work in any engine without bleeding the oil pressure.

What program are you using for the gear calcs?

Just this website.

https://www.blocklayer.com/rpm-gear.aspx

i dont understand how an un-shrouded roll would bleed oil pressure ? unless its the wrong length to suit the lifter bore ?

i would expect that at full lift it shouldn't expose the roller, are you meaning at high lift it is getting into the lifter oil gallery a bit ?

funnily enough i found this on google https://www.performanceboats.com/gn7-dy ... ost1624833

Are 3.73 gears m75 or m78 or whatever it is to suit 6cyl vt irs?

Was told some modding required like larger 22mm nut on longer shaft & some housings might need some clearancing but yet to find someone 100% especially now that they're NLA & priced sky high now

Holden202T wrote:i dont understand how an un-shrouded roll would bleed oil pressure ? unless its the wrong length to suit the lifter bore ?

i would expect that at full lift it shouldn't expose the roller, are you meaning at high lift it is getting into the lifter oil gallery a bit ?

funnily enough i found this on google https://www.performanceboats.com/gn7-dy ... ost1624833

The oil gallery is low down on the lifter bore, right over where the shroud is so not having one the oil just pisses straight out the galley as it's uncovered.

Problem is you have get hydro roller lifters that suit with full shroud but I have not seen any mechanical ones that do. Looking more and more like I will have to have a custom version made.

I am looking at have these customized as the base forging is fully shrouded but they cut some of it away. Although it looks like it might work I measured from the pic that the cut away area is only a few single mm away from the galley in this case at full lift as well and at no lift the top of the "collar" part is also a bit too high and might not let the oil into the turned down area. I really need it to be based on the dimensions of the OEM lifter to work, but be link bar and mechanical.

https://www.johnsonlifters.com/Products ... 116SB.aspx

I'm thinking about getting one pare of them to be sure if it will work or not and note the changes either way for custom ones. One option is maybe even get the cam deliberately ground with a smaller base circle than it will already would have to drop the lifter down, it will fixed both cut away and raised collar issue but not sure on reducing the base circle by say 6mm diameter is a good idea.

gtrboyy wrote:Are 3.73 gears m75 or m78 or whatever it is to suit 6cyl vt irs?

Was told some modding required like larger 22mm nut on longer shaft & some housings might need some clearancing but yet to find someone 100% especially now that they're NLA & priced sky high now

It's an M75 gear set so all good for the VP, drop in basically. Some guy chimed in and reckons they are cortina. I'd say that's about right, I've heard 3.73 M75 for fords and skylines but not in holdens. Come to think of it I think my 3.23 in the red car came out of a ford too, also a ratio I had not seen in holden M75.

HSV released a very limited run VP model which I believe had 3.23 gears. Holden really did drop the ball running 3.08 gears in everything.

3.23 was also factory in all Vk 6 cylinder from 1985 when they fitted the borg Warner.

Johnson should make there same ls7 lifter in a solid or get someone to turn you up 12 solid plugs to fit in the stockers and drop the top seat on top of it and clip the retainer ring back in that's how we used to make solids years ago lol