8 replies to this topic

[nanbar]

Hi All

I am trawling through the hundred of posts on LC/LJ V8 conversions, in the mean time, I am wondering in the brains trust on here can short cut me to info on the best options for exhaust manifolds that provide the best clearance to the steering staft. I currently run extractors and the shaft has the two  LX/LH couplings. I have seen that people use standard factory manifolds instead which provide better clearance. I'm chasing more clearance but am not sure if its commodore manifolds or HQ-WB ones that I need to use. I have an early style 308 (ie pre VN).

All help/pointers would be appreciated.

Cheers

Nando

[Shiney005]

I don't know...........but I guess LH / LX would be your best bet?  Some of the 308 Bedford trucks had manifolds that tucked in nice and close as well.

Edited by Shiney005, 06 January 2026 - 01:00 PM.

[rexy]

It might be easier to modify your existing pipes?

I have custom pipes in both my LJs which are multi piece which makes it very easy to remove them without moving the engine, crossmember or box.

[nanbar]

I don't know...........but I guess LH / LX would be your best bet?  Some of the 308 Bedford trucks had manifolds that tucked in nice and close as well.

Thanks

It might be easier to modify your existing pipes?

I have custom pipes in both my LJs which are multi piece which makes it very easy to remove them without moving the engine, crossmember or box.

Thankyou, Ive got it booked into an exhaust place on the 16th, when he looked it before xmas he thought Im pushing shit up hill but he'll give it a go. I looking for plan B.

[yel327]

I don't know...........but I guess LH / LX would be your best bet?  Some of the 308 Bedford trucks had manifolds that tucked in nice and close as well.

 

 

LH and LX driver side V8 exhaust manifolds are the same as HT-WB Holden ones (heat tube variation aside). It is the passenger side that differs.

 

Relevant but slightly off topic:

 

Does anyone have GMH docs that show why the U-body (Torana) used different V8 engine location via the mount adapters to H-body (HK-HG) and W-body (HQ-WB)?

 

What I mean is why is the V8 engine in a U-body slightly higher and further forward? Is this to have sump and firewall clearance?

 

Is the different left side exhaust manifold a result of the engine moving a bit? Or is that required regardless?

[Shiney005]

What I mean is why is the V8 engine in a U-body slightly higher and further forward? Is this to have sump and firewall clearance?

Both?  Certainly firewall / fan duct clearance. 

[308 Sunbird]

I always thought it was so the bottom of the sump sat higher than the bottom of the K-frame?

[nanbar]

I always thought it was so the bottom of the sump sat higher than the bottom of the K-frame?

Sump bottom sitting above the Kframe would be nice in my case, it's one of the issues I have (sump/cross member clearance not enough). Having said that, if the motor sat higher the booster and rocker cover would clash.

[gtrboyy]

Hurricane extractors by Liverpool Exhaust were good...they were 2 piece items.

Used the top & remade bottom piece to clear steering shaft.

Being able to remove bottom piece made them easy to fit.