Split Dellortos - 40 or 45s

[Pedro Motorsport]

Hi all,

I'm currently building a 1300 8v vauxhall smallblock engine to go in a road rally Nova (hence splits being used)
I'm hoping for around 130-135bhp out of it when built, however I've got two pairs of dellortos (40 & 45 respectively) and was wondering if 45s would work on this engine?
Reason I ask is in future I will most probably upgrade to a 1600 or 1800, at which point the 45s would be called upon. I'd sooner not split two pairs of carbs if it can be avoided.

Thanks in advance

[Graham]

on the basis that ive known people run 1600 x/flow on twin 50's and a bloke that ran a 1000cc imp on a pair of 45's, i dare say you could use a 45 you might need 32mm choke to make it pick up from low speed though

[alladdin]

on the basis that ive known people run 1600 x/flow on twin 50's and a bloke that ran a 1000cc imp on a pair of 45's, i dare say you could use a 45 you might need 32mm choke to make it pick up from low speed though

given they are splits would the req. chokes need to be bigger ?

[Graham]

given they are splits would the req. chokes need to be bigger ?

yes but 1x32mm choke in a 45 feeding two cylinders on an 8v 1300 is probably plenty if you want it to pick up reasonably well from lowish speeds

[Forest_rallying]

I would have thought split 40's would be adequate for a 1300 Road Rally engine with the correct chokes fitted, theres no point in going too big otherwise you'll have no low down torque for the twisty lanes of Wales. You can then save your 45's for a future project.

[Graham]

I would have thought split 40's would be adequate for a 1300 Road Rally engine with the correct chokes fitted, theres no point in going too big otherwise you'll have no low down torque for the twisty lanes of Wales. You can then save your 45's for a future project.

that was the OP original point he wants to upgrade the engine later on to a bigger one, but didnt want to modify two sets of carbs, hense why i said fit small chokes to the bigger carb

[Forest_rallying]

that was the OP original point he wants to upgrade the engine later on to a bigger one, but didnt want to modify two sets of carbs, hense why i said fit small chokes to the bigger carb

I thought he'd be better off not cutting up a pair of a decent set 45's, instead saving them for if he ever wanted to go onto Stage Rallies at a further date.