Author Topic: 1043 G40  (Read 3909 times)

Offline randombadger69

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1043 G40
« on: February 27, 2012, 10:58:19 am »
Anyone G-charged a 1043cc before?

..Other than Phils comedy build!

I stripped out a 2G block. Which confirms the bore to be 75.0mm. I measured the rods and they are the same length as the PY rods.

Which makes me think all i need to change is the crank into a PY block to create a 1043cc with low compression?

Ideally i want to build a 1043cc turbo, but as i have all the gubbins to run it with a G-lader, im thinking of testing the water first before i invest in turbo componentry.

Just wondered if anyone else has had a play around with the 1L lumps and boost.

Offline hayesey

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Re: 1043 G40
« Reply #1 on: February 27, 2012, 04:40:00 pm »
wouldn't the crank alter the stroke?  putting g40 pistons in would lower the compression wouldn't it? 

Offline randombadger69

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Re: G40
« Reply #2 on: February 28, 2012, 07:16:38 pm »
This is what im hoping. That the py pistons and rods will lower the compression to 8.0:1 with the 2g crank. One way to find out. . .

Offline Andy

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Re: 1043 G40
« Reply #3 on: February 28, 2012, 08:36:55 pm »
What's your aim with this?

Offline ereeiz

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Re: 1043 G40
« Reply #4 on: February 29, 2012, 10:21:55 am »

Offline randombadger69

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Re: 1043 G40
« Reply #5 on: February 29, 2012, 12:59:58 pm »
^ ;D

What's your aim with this?

To build a high revving boosted engine. Im also interested as to what sort of power can be achieved from 1043cc. In the back of my mind im toying (dreaming) about Group H 1150cc category.

1043cc + 2mm overbore?

From what iv gathered stroke provides torque. A lot of Vee race engines seem to have say a bore of 80mm and a stroke of 50mm in comparison. Making the engine geared more towards higher revving power rather than torque.

Seems not many bother with the 1043cc displacement, binning it in exchange for a 1272cc. Which is understandable.

At the eschdorf round of the berg-cup last year, saw this Audi 50 in the 1150cc class. It was flying, sounded N/A.



Just an experiment really, im hoping i can do it on the cheap. A hone, a set of rings, new shells and maybe a skim of a cyl head (depending on how flat my spare is).


Offline SamG40

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Re: 1043 G40
« Reply #6 on: February 29, 2012, 02:22:05 pm »
Laders dont like massively high revving. Quite easy to take the bearings outside of their happy happy tolerances.

Offline randombadger69

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Re: 1043 G40
« Reply #7 on: February 29, 2012, 02:54:22 pm »
Yes indeed, ideally i will use a turbo. I Just want to get something running with boost to start with before i spend out on a turbo/make a manifold etc.

Turbo will make it easier fitting the engine in my mk1 golf as well. I can use the golf o/s engine mount instead of having to use the polo, G-bracketry.

Out of interest what would you say the highest revs a G-lader can handle without imminent death?

And whats the standard ratio i.e. with the engine idling at 1000 RPM what is the G-lader Revving at in relation with factory pulley?
« Last Edit: February 29, 2012, 02:59:24 pm by randombadger69 »

Offline PeteG40

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Re: 1043 G40
« Reply #8 on: February 29, 2012, 03:28:10 pm »
1.6 x crank revs... theres some calcs i did regarding the top lader bearings in a post on here somewhere

http://www.polog40.co.uk/forum/index.php/topic,7198.15.html

normal top bearings have a limit of 12,600rpm

the charger spins 1.6x crank speed on a 76mm normal pulley.

therefore at 6500rpm= charger spins at 10,400 rpm

76/65 = 17% smaller (ish)

therefore a 65mm pulley is 12,160rpm

a 60mm pulley is 13,173 rpm

a 58mm pulley is 13,628 rpm


Offline ereeiz

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Re: 1043 G40
« Reply #9 on: March 01, 2012, 11:15:43 am »
I thought it was the seals that gave up over a certain RPM. If it's just bearings then a harder wearing/ more expensive variety could be found surely?

Offline randombadger69

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Re: G40
« Reply #10 on: March 01, 2012, 02:30:49 pm »
Cheers for that pete. Your wealth of g40 knowledge never fails to impress! What causes bearing failure in this instance? Excessive heat? Insufficient lubrication? The cartridge bearings could certainly be upgraded. Full ceramic being a viable option? Although at £100 a go, could get expensive!

Offline PeteG40

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Re: 1043 G40
« Reply #11 on: March 01, 2012, 02:41:00 pm »
i think its excessive heat causes the seals to fail and then dirt ingress and  or grease loss. This causes further heat and bearing seizure.. and therefore timing belt slips/snaps.

Offline Raw

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Re: 1043 G40
« Reply #12 on: March 07, 2012, 01:03:00 pm »
Bit of a contradiction in wanting to build a high reving enigne at low cost but I can see the apeal.

Matching the laider to the revs is just a question of pulley size; you need to go bigger. Also the standard G40 fuel system, inlet & exhaust setup on a 1 litre will flow plenty enough. In fact if you can just increase the revs by 20 - 30% and match the charger revs accordingly with a remap or aftermarket ECU you should easily make the same power as a G40.Could you stick a G40 head on there too?

Then you need to look at what else is over reving and becoming stressed, Oil & water pump (cavitation?) Distributor. Look for increased wear on all the bearing. Choose your gears cairfully too

Offline G40supercharged

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Re: 1043 G40
« Reply #13 on: March 07, 2012, 09:45:19 pm »
This rev counter might be useful

Offline randombadger69

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Re: 1043 G40
« Reply #14 on: March 07, 2012, 09:49:15 pm »
I wish i could afford/was clever enough to get it revving that high ^

Bit of a contradiction in wanting to build a high reving enigne at low cost but I can see the apeal.

Matching the laider to the revs is just a question of pulley size; you need to go bigger. Also the standard G40 fuel system, inlet & exhaust setup on a 1 litre will flow plenty enough. In fact if you can just increase the revs by 20 - 30% and match the charger revs accordingly with a remap or aftermarket ECU you should easily make the same power as a G40.Could you stick a G40 head on there too?

Then you need to look at what else is over reving and becoming stressed, Oil & water pump (cavitation?) Distributor. Look for increased wear on all the bearing. Choose your gears cairfully too

I know what your saying regarding cost and revs.

This is a bit of an experiment really.

So far I have in the G40 parts bin:

PY block, pistons and rods.
2G crank
G40 oil pump (anyone know flow rates on this, is it in the haynes?)
G40 head
Choice of camshafts either PY,2G,MH or 3F standard or a 272 Dbilas.
3F inlet manifold
G40 Exhaust manifold and downpipe.
A couple of worn G-laders (will be getting a re-build on one if they're repairable).
G40 fuel pump
GT gearbox - may need revising.

Ignition may well be something that needs alteration in time.

I read that the standard hydro buckets are good for 8.5K revs? I see Bar-tek tuning do buckets for over these revs.

Doubt i'll be pushing past that at this stage.