between me and a mate we are building a xr2 engine a carb model... and so far weve got a 60.000 skimmed head, cam kit and a gass flowed exhaust manifold with the box/ square xr2 twin choke carbs. is there any more ways to push that little bit more bhp through the engine(without using twin webbers) if so wot roughly wud it be and how much....

 

alright mate. i was going to sugest twin 40s but never mind. get yourself over to www.xrtwo.com its like passionford only just for the fantastic xr2.
i can think of:
4 branch manifold
panel filter
full stainless system

 

Mate of mine links the 2 chokes together so they open at the same time, dont know the exact details of it but seems to work

 

If you play around with different jets for the carb, you should get the power smoother

Try getting some ducting to force the air to the air filter [if you're using a K+N??]

The BEST thing to do tho to make it rev happy is to get the fly wheel lightened and balanced

 

what am i looking at for a lightened and balanced fly wheel..

 

also if i force air into the carb wont it stall.. so id have to control the pressure it entered?

 

Sorry, not "forced induction" I mean like some ducting from the front of the car, to make sure [if you're using a K+N or equivalent] you're keeping the air temp down.

Because of where the air filter is situated at the back by the bulk head, its at a high pressure point [unless you use bonnet raisers and it becomes a low pressure point ]

OR you could fit a scoop right next to the filter??? make sure the rain doesn't run into it tho

I would imagine you could get the flywheel lightened and balance for no more than £100 tops, better off ringing an engineers firm like Roe in Fleet, Hampshire [Mrs Frog has the number] for an idea of price.

You WILL notice a difference with that done, the car will rev up quicker

 

if youve not touched the bottom end yet then its worth either getting it bored to a 1640, or putting a seirra 1.8 cvh bottom end on.

to get it on and going proper, you want to put 1.8zetec pistons in there, the compression on a 1.6 head is very low, even with your skim id imagine itd still be around 9:1-9.2:1. with the zetec pistons in itll bring it right up.

you then need to weld the top part of the 1.8 sump, to the bottom part of the 1.6 sump. easy enough to do, they line up fine. then with the sump modded to need to slightly mod the oil pickup. its obvious when you come to do it what needs to eb done.

with that head, cam and a webber DMTR carb itll easy be knocking on the door of 140+bhp. theyre torquey bastards too.

the DMTR by the way is a webber upgrade carb from the DFT. itll fit on the DFT manifold, but might need the inlet trimming slightly on the manifold. they go for about £200 brand new but they come up on ebay quite often. fucking good carbs them!!!

hope that helps you a bit mate!