Replying to previous comments re 1 piece Commer to Perkins Adaptor
I do have a 1 piece adaptor but it came off a Non turbo Perkins. I will be using the #2 Adaptor as the Turbo Flywheel and Pressure Plate are a lot heavier than the non turbo and quite a bit thicker too so won’t fit into the single piece adaptor.
On the non turbo, the input shaft of the Commer gearbox is located into a bearing on the back end of the crankshaft while in the turbos the bearing is fitted into the centre of the flywheel.
2nd photo is the 6 speed Commer gearbox....it’s a heavy unit and it came out of a Dodge D3F. I’m going to have to raise my cab and front clip about 65mm to get all this in. Will have to cut a hole into the firewall also. The 6 speed must have been an after market fit in the D3F as the records I’ve seen only show a 5 speed.
I’ve also got a non turbo Perkins at home which I’ll be putting on the market along with the 250 side valve, but not until this project is up and running.
Ive put quite a few 354 s in little trucks...........you will need a minimum 1350 size uni........and with 7.50 x16s I would go with a 3.5 ratio,if you want a bit of load shifting a 4.3 from a IH is ok.......thats 2800 revs at 100kph. in direct,so would be Ok with OD........the uni size is the main thing tho.......the smaller unis are ok with petrol motors ,a perk breaks them straight away.
Replying to JOHN.K.
Thank you for your reply.
My diff ratio is 5.85:1 but my tyre size is 7.50x20.
On the flat I could sit on 80km/hr with the side valve and am hoping to be able to cruise around 95 with the Commer overdrive..
Before I took the gearbox out of the D3F it could cruise at 100km/hr. Admittedly it had a faster diff than my Dodge but the D3F only had 16” wheels while mine has 20”.
Could you please let me know how I can check my uni’s to see if they are bigger than 1350.
I will be using the tailshafts and unis out of the D3F BUT will have to go down to my 359 Dodge uni at the back tomatch up with my diff.
I was wondering how you may have modified the crossmemmbers on the trucks you put the 354’s in.
I propose using the standard Perkins metalwork and the rubber mounts. To do this I will have t cut a bit out of the engine side of the front crossmember and weld in box section to take the Perkins mounts which will sit about 60mm below the top of the crossmember. The crankshaft pulley will sit about 15mm above the centre rear of the crossmember.
Interested to see how you did it.
The simplest way,I think is to modify the rear mount crossmember from a bigger IH perkins truck.......this then uses the whole setup from a bigger truck......The front holes are OK,and the 4 speed from a 1600 with its housing then fits straight onto the perkins flywheel housing......this is the IH one ,not a round one........A simpler way to do it ,is if you can find the one piece housing from a ASD 172......which had a R6 perkins....a rare motor.....Another simple way is to find a Dodge perkins motor with the one piece Dodge housing from a Ozzie Dodge Perkins.like a 675....but then you need a Dodge box,I used the 5 speed NP.......basically ,you need a Dodge Perk to wreck.......The last one I did is a D1310,and is quietly rusting away in the back yard,and I used all IH bits......It was a great old truck ,often had so much on the truck and trailer the Perk was struggling to start on a hill.........record was 7.9 ton gross over the scrapyard weighbridge....Just the truck.,another 4 ton for the trailer....That was from Boral...they said you can have everything you can load up.........soon as you go ,the gates locked ,and thats it............they gave me a crated Ruston 5 YEN motor from a RB 38 dragline ......brand new spare......Those were the days.
Dazza, my mighty perk ACCO has only a simple single front mount in the middle of the cross member. The perk was done around 1970 by 2nd owner, replaced a V8, I assume it is copy of factory fitting. Apparently perks and ACCOs were common enough but not enough in the same factory so lots were retro fitted by local mechanics.
The V8s had an extension rivetted to the front crossmember.......blow out the rivets,take off the extension,and you will generally have two 3/4 holes in the front crossmember.......this is for both 6cyl petrol,and inter perkins.......I see you have the angled Dodge/Commer /Leyland fronts......these can be used if you fabricate a crosspiece...........the long bonnet trucks need a 3 point mount.....the chassis are too flexible for four point,and will tear apart 4 point.......The actual IH Perkins front is two right angle pressed fronts on the block,and a cast crosspiece with a pocket for a rectangular rubber .........the later ones had bigger holes where they mount to the block..............Actually,if you use a prper IH Perkins setup,front and rear,the petrol 6 holes are a bit too long.....about 1" from memory.