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Is boreing a xflow worth it
spoonana - 17/10/11 at 10:57 AM

Hi,

I've currently got a bog standard 711M 1300 Xflow engine. Im going to use it to race in the 750 Locost championship but I want to know if there is any benefit of boreing out to 0.090".

If not where does all the extra power come from???

Cheers

Max


D Beddows - 17/10/11 at 12:19 PM

Yes, you end up with effectively a 1400cc engine rather than a 1300

As to the rest of it, there's no big secret really (there used to be a long time ago but that's another story ) they're just effectively brand new engines, properly balanced, with all the right clearances etc and set up on a decent dyno. You do need a good exhaust mind you to be up with the best of them.

[Edited on 17/10/11 by D Beddows]


James - 17/10/11 at 12:47 PM

quote:
Originally posted by spoonana
Hi,

I've currently got a bog standard 711M 1300 Xflow engine. Im going to use it to race in the 750 Locost championship but I want to know if there is any benefit of boreing out to 0.090".

If not where does all the extra power come from???

Cheers

Max



I may have misunderstood your post, but are you sure you're allowed to run a larger engine in the championship?

Worth checking before you make your engine useless to you!

Cheers,
James


Dave Ashurst - 17/10/11 at 12:49 PM

Worth a read perhaps (plus the other articles linked off the main webpage)


D Beddows - 17/10/11 at 01:21 PM

The Puma Racing Engines article is an interesting read - unfortunately it contains very little you can do to a 750MC Locost engine. I will admit that it's a while since I used to build them but it is/was really just about putting the engine together properly - something Ford didn't really bother to do back in the xflow days. The engines would work fine from the factory but with a bit of time and effort there is usually quite a bit more to get from them even in standard trim. It's not cheap mind you - for a top spec engine built yourself (so no labour charges) you wont really see any change from £1000 quid in terms of parts and machining, then there's maybe £3-500 for the exhaust on top of that.......

Locost Race cars are a SERIOUS bargain when they sell for £5ish grand considering the time, money and effort that going into putting most of them together!


AndyGT - 17/10/11 at 01:29 PM

Can you use the 1100 pistons too? Or not? Just this is a cheap and effective way of raising cr. If not, I'm sure there is some HC pistons available from GT and ghia versions. Or the whole hog of using powermax pistons from a twinkie?


D Beddows - 17/10/11 at 01:51 PM

Nope have to be 1300 xflow pistons (the part number is in the regs) - everything has to be 1300 xflow and the cam has to be a stamped one direct from Kent Cams (people used to take the p*ss with 'cheater' FFord cams)

[Edited on 17/10/11 by D Beddows]


Trollyjack - 17/10/11 at 04:21 PM

Hi
Sorry for butting in but just stripped my engine and found some items that should be a 1300 gt engine but could not be
please read below
valves are 110.6 long have been told that by a valve suppler that a 1300 gt engine that they should be 109mm long

according to locost regs thet should be 110.6 long

also piston tops on a gt engine are different to std 1300 see pic out of haynes manual

pistons
pistons


My pistons are the ones on the left

Also what other differances are there between a normal 1300 and a 1300Gt engine

Can someone please clarify


steve m - 17/10/11 at 05:26 PM

The Cams on the xflow are only stamped on the flywheel end, and as such a real PITA to get to
i would imagine, some of the locost racing brigade use a hotter cam, and get away with it


D Beddows - 17/10/11 at 06:24 PM

They used to - now they don't because they all have to buy specially stamped camshafts from Kent cams......... as I may have mentioned above........

Trollyjack - what's the number on the block? the very early crossflow engines could be a bit of a combination of parts tbh


[Edited on 17/10/11 by D Beddows]


Trollyjack - 17/10/11 at 08:00 PM

I'll have look next time i'm in the lockup


ShaunB - 17/10/11 at 09:47 PM

From the 2011 Locost regs:

"Pistons must be AE Part No: AE18647 (up to +0.090" ) to either of the forms and dimensions shown in the illustrations in Section 6 of these regulations. Whichever form is used, all dimensions must be from the same illustration. Piston rings and gudgeon pin must be standard for those pistons. All rings must be fitted and the gudgeon pin may not be modified. Pistons may not protrude above the block face"

Download a copy of the regs: click me for regs

FYI, I picked up a brand new set of pistons but still had to remove weight from 3 of them to get a properly balanced set (you are only allowed to balance items to the same weight as the lightest component of the set of 4).

If you get a new cam I think that as well as being stamped on the flywheel end, they are also engraved on the fuel pump lobe that isn't used. This allows an easy check by removing the fuel pump hole cover plate and looking in.

Shaun.

[Edited on 17/10/11 by ShaunB]


procomp - 18/10/11 at 11:38 AM

Hi

Boring out to +90 is going to give the edge over a +60. However there are some who go out to +60 so as to have the option of a further bore should the bores encounter any bore wear or ring problems at some point, that however is a personal choice.

RE the pistons and part numbers that are in the 750Mc regulations. Although you can buy the pistons from various sources you have to check the ACTUAL bowl depth of the pistons you have brought due too the fact that when AE moved production from one plant to another they changed the drawings. This means that there are quite a few pistons out there with bowl depths that are to shallow.
If you would like a guaranteed set of pistons for the championship that are correct and balanced give me a call as we have the supply off correct ones and far cheaper ( for Locost competitors ) than the other various suppliers.

Cheers Matt


spoonana - 20/10/11 at 09:35 AM

Thanks for this,

So i need to...
Get a 0.090/0.060" bore and matching pistons
a stamped kent cam
the engine put back together properly
a good dyno run to get it balenced

Anythinv else i need to do or forgotten???


Max


procomp - 20/10/11 at 09:53 AM

Hi

Others to check / sort. Front crank pulley get the one piece one from Burtons as mentioned in the regulations. The STD Ford two part spot welded comes at part and can result in serious engine damage. Also make sure your flywheel / clutch assembly and mounting bolts are to the correct weight. 10.5 KG. ( double check that in the regs as i am unsure off the top off my head toooo many regulations/ championships and toooo few brain cells ).

Cheers Matt

PS. You'll want the pistons first for the machinist to bore to the piston.


spoonana - 20/10/11 at 12:19 PM

Right ok, i think i can hear my wallet screaming


procomp - 20/10/11 at 01:35 PM

Hi

The way to look at it is , if you do it right first time it's a darn sight cheaper in the long run. It's also worth thinking that if you where to miss one round and put that money into parts that are reliable / right it also pays in the long term also. Don't rush these things it only ends up expensive long term when you still end up having to do it right after it went wrong.
I have got an engine out there that won the first ever championship and due to being prepared right in the first place is still winning races when the car races now.

Cheers Matt


ShaunB - 20/10/11 at 04:08 PM

Something else to think about is replacing the exhaust valve seats and valves with some that are suitable for unleaded fuel. It's difficult to get a lead replacement additive that does not also include an octane boost - which isn't allowed.

10.5Kg is correct, that's for everything: flywheel, friction plate, pressure plate, and all mounting bolts.

Shaun.