Birkin Crossflow spec

[BEN99W]

Hi

 

Ive recently bought a Birkin that was built in south Africa then exported to Japan and is now in New Zealand. Ive no details about it and wondered if anyone with experience of similar had an idea of the spec Birkin used. It has twin weber 40s with 32mm chokes and a long branch 4 into 1 exhaust which also has a cat which I find strange and is running some sort of Ford engine management via the distributor. Everything looks original on this car, its only done 15k km and hasnt been on the road for 15+ years. Im interested, because Im going to be in the UK shortly, and in a position to pick up some tuning parts if the factory specs were rather lowly. On the other hand, if they used a decent level of kit from the factory, then Ill limit myself to stockpiling consumables. 

 

It isnt even on the road yet and Im already anticipating upgrades 

 

Thanks in advance.

 

Ben

 

 

[wdb]

A quick google search seems to say that Japan requires catalytic converters on virtually all vehicles. That might explain some of the added bits. 

 

Crossflows are used in Formula Ford and can be tuned out the wazoo. I believe parts are easily available from a variety of vendors.

 

If it were mine I'd remove the catalytic converter and engine management foo, go through fuel system/brakes/tires/etc. to verify road worthiness, and take it for a drive. Then I'd decide if it needs more power.

[IamScotticus]

I agree with the take possession,  evaluation then execution approach.  You should learn a lot more about the Crossflows before making changes.  Remember there is much to pay attention to with the diff, axle and transmission. Know what you have and what cars used those parts.

 

Don't be quick make engine improvements and neglect all else. It's the drive train you're looking at having the most difficulty finding replacements for.

Get the car in hand, resist the temptation to run it before having a professional preparation check everything. 

I have seen someone destroy an engine as soon as he received it.  Don't be that guy.

 

The crossflow is a SMALL ENGINE.  a little more power can be coaxed out of it with the spec you already have,  but not much more. Going to the extremes the racers do gives them a few seconds off thier time, but it won't make that much difference on a road toy.  You have a fun and reliable engine the way it is. Keep it that way.

Put money into fiberglass spares. 

[BEN99W]

I certainly get what your saying with regard to getting to know the car before changing anything,  which is partly my enquiry. I cant get any answer to what specification of engine was used by Birkin. I could have anything from 100 to 160bhp. That's a big variation in a Seven.

[NSXguy]

If you can share photos of the car/engine and we can probably be more helpful.

 

If S.A built, it may have an AX block installed which is the best(read -strongest) for tuning/upgrade purposes. It sounds like it is running wasted spark ignition which is nice as you can achieve a tailored ignition curve and thus better performance than the standard distributor based setup. Twin 40s, 32mm venturis and 4 to 1 collectors hitns at an engine that is built to rev. You'll likely(possibly) find that it has an upgraded camshaft and double valve springs as well. 

-Dez

[pethier]

1 hour ago, NSXguy said:

If S.A built, it may have an AX block installed which is the best(read -strongest) for tuning/upgrade purposes.

How can I find out if my Birkin has an AX block?  Engine serial number?

[11Budlite]

It should be in the casting like this.

[7Westfield]

front left corner

probably behind the alternator bracket

 

If you're ever over at Rich's, look at the motor in his Dulon

Edited July 17 by 7Westfield

[pethier]

1 hour ago, 11Budlite said:

It should be in the casting like this.

thanks

[pethier]

1 hour ago, 7Westfield said:

front left corner

probably behind the alternator bracket

Thanks

[IamScotticus]

@BEN99WBEN99W very unlikely Birkin would have changed crank and pistons, too expensive.  The most likely upgrades are cam, lightweight flywheel, carbs, exhaust, valve springs.  The cam number should be visible on the end when, if, you inspect the timing chain, tensioner and coolant pump. 

Work  I know. Better to know what you have than be sorry on a road somewhere. 

Three good places to learn about Kent engine is Burtonpower,  Pegasus Racing and Dave Bean Engineering.  For Bean, you have to order the Ford Engine catalog.. on Pegasus there are general guides and parts but the book by Jake Lamont is worth getting with any order fron them.  The other builders book Kent specific is by Peter Wallage ISBN 1-85010-938-9.  These two books stay within reach if the house is burning, they get saved.

More info and support in the Ford Escort and Formula Ford sources. Other Lotus cars, Westfields, Morgans had Kents.  Other builders like Ivey and Montune will build an engine but they don't support the DIY builder.

You should have Haynes manual # 139 for Escort Mk1 1600 Mexico 1970-74 ISBN 085696-139-6 to get a good understanding of the engine assembly.

 

See this too

https://thekentlives.com/

Edited July 16 by IamScotticus

[BEN99W]

@IamScottucus Thanks, that's a very useful answer.