Upgrading from TB42 to TB45 in GQ Patrol

Hi All,

I have a 1990 GQ Ti (High roof model) and would like to get a bit more power (mainly for better towing capability). It has a naturally aspirated TB42 with dual fuel set up.

I am wondering if it is possible to put a TB45 straight in without legal issues, such as engineers certificate etc...

I would like to stay with a naturally aspirated set up if possible. I noticed that the compression ratios on the EFI TB42 engine is different to the naturally aspirated TB42 (8.3:1 for Nat. Asp. as opposed to 8.5:1 for EFI) I therefore assume the TB45 with a compression ratio of 8.5:1, if run as naturally aspirated might be better at 8.3:1??? Does anyone know if this slightly higher compression ratio will make a detrimental difference to things if I run it naturally aspirated? Are there better solutions?

I have attached a pic of the vehicle and hope I have done it right so you can see it....

Any thoughts and advice backed by experience would be greatly appreciated!

Thanks.

The TB45 was first introduced in 1997 so to fit in a 1990 GQ you would require full Engineers certificate

OK, thanks Bob.

That saves me a lot of time and mucking about.

I thought there was a 30% increase in capacity allowed, as long as you did not change mounts etc?