R8 gordini engine rebuild

[jaahn]

When using 'Quick reply' to post (just below the most recent post), look above the white box where you type and you will find a row of icons. Click 3rd from the right (Insert Image) - this opens the 'Insert Image' box. Click 'From Computer' then click 'Select Files'. Now you can search on your own computer (internal drive or external, such as USB stick) and select the photos you want to upload (hold down the CTRL key if selecting more than one) then click 'Open' button. This brings you back to the 'Insert Image ' Dialog box. Now click 'Upload Files' and Bob's your father's (or mother's) brother!

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Now double-click on one image - this opens the 'Image settings' box. From here you can choose the size and alignment of your uploaded photo.

If you are posting from the 'Go Advanced' page, then it's a bit different...
Cheers Alec

Hi stcos85
Just to add to these instructions a liitle.
The pictures need to be reduced in size before you start trying to upload them. So first go to your computer picture program and select the pictures you want to send and edit them. In the edit mode it will have a resize button or option. Just select the smallest or second smallest size offered and the program will then do a resize and save it as another picture. Use these when you upload as the site will not accept large picture files.
I find you can only do one picture at a time and have to repeat that procedure to get them all on. Good Luck.

On another front, in the old days we built up an 1100 Gordini motor using a normal 1100 R8 crank/rods/block with new G pistons and a G head and a reprofiled std cam. The bottom end worked OK and was flogged every day without any problems.
Jaahn

[Manic GT]

From what I understand of the 1108 and the other Cleon smaller engines for the most part the rod lengths are the same , and the crank journals on the 688 and 1255 and 804 are all the same but the wrist pin ends are smaller on the 688 units at least on the ones that I own . I would suggest to either use the heavier 810 rods and bush them or upgrade to the 1397 rods and float them . From the information I have The stock 1108 crank is not hardened like the 1255 / 812 or 804 crank but same results may be acquired by shot peening the crank . If you are to build a similar engine you may want to use the newer 1108 crank that allows for the extra bolts and larger clutch plate . I also included pictures of the distributor shafts of a 810/688 unit and a 810 /1255 unit . For additional info the 804 heads can be install on the larger 1397 engines the bores will fit onto the engine even with the dissimilar head spacing .
.

hope this is helpful

Manic gt

[JohnW]

From what I understand of the 1108 and the other Cleon smaller engines for the most part the rod lengths are the same , and the crank journals on the 688 and 1255 and 804 are all the same but the wrist pin ends are smaller on the 688 units at least on the ones that I own . hope this is helpful Manic gt

I'm sure it will be!! Good you are around out there and thanks for the useful photios. I'm pondering an 810 motor sitting on my floor from an R10 1300 (very rare in Oz) right now.

[Frans]

Hi,

Measurements done and this is what I found:
The conrod length center to center =128mm.
The Gordini piston gudgeon pin = 20mm. Standard 1108 =18mm
The Gordini piston deck height =39.5mm standard 1108 =37.5mm Not sure of this one as the sizes were taken from a 1400.
The piston bore of the Gordini =70mm standard 1108 =70mm.
the stroke of the Gordini =72mm standard = 72mm.

Remember that with the combination of standard bore and G pistons the rods must be 128mm. Any 1289 or 1300 the rods will be shorter to compensate for the longer stroke of 77mm.

So all these sizes doesn't help if we can't compare with stock 1108 or 1289 sizes to assist in building a engine for Stcos85.

These 2 photos is that of a 1100 Gordini piston. This is what the pistons should look like. Different to the 1255 ones.





This is what the conrods look like on this engine. Remember I said it had a hard life, so what I noticed is that it is different from what Simon said. These don't have bushes so I think they have been re-sized in the past.





To get back to solving the problem I am sure that if we can get a set of 1108 rods with its 18mm hole, it can be safely increased to the desired 20 mm of the pistons. There is even a chance that it can be machined with a slight offset to adjust piston heights in the case there is some discrepancies.

Please correct me if anyone sees a mistake but I think it is very possible to build a nice engine even if there isn't a 100% Gordini content.

Regards, Frans.

[stcos85]

Hi,

Measurements done and this is what I found:
The conrod length center to center =128mm.
The Gordini piston gudgeon pin = 20mm. Standard 1108 =18mm
The Gordini piston deck height =39.5mm standard 1108 =37.5mm Not sure of this one as the sizes were taken from a 1400.
The piston bore of the Gordini =70mm standard 1108 =70mm.
the stroke of the Gordini =72mm standard = 72mm.

Remember that with the combination of standard bore and G pistons the rods must be 128mm. Any 1289 or 1300 the rods will be shorter to compensate for the longer stroke of 77mm.

So all these sizes doesn't help if we can't compare with stock 1108 or 1289 sizes to assist in building a engine for Stcos85.

These 2 photos is that of a 1100 Gordini piston. This is what the pistons should look like. Different to the 1255 ones.





This is what the conrods look like on this engine. Remember I said it had a hard life, so what I noticed is that it is different from what Simon said. These don't have bushes so I think they have been re-sized in the past.





To get back to solving the problem I am sure that if we can get a set of 1108 rods with its 18mm hole, it can be safely increased to the desired 20 mm of the pistons. There is even a chance that it can be machined with a slight offset to adjust piston heights in the case there is some discrepancies.

Please correct me if anyone sees a mistake but I think it is very possible to build a nice engine even if there isn't a 100% Gordini content.

Regards, Frans.

My rods are same as these without the hole innthe small end. It measures 128mm centre to centre. Do you think these will be able to be taken out to 20mm. If so that doesnt allow for the brass bush though so is there an alternative to having to bush it

[Frans]

That is good then. I am sure these rods were taken out to 20mm as well. So you have rods that can be used. They must be reamed out to 20mm with a slightly bigger size, the engineering shop should know what the clearance must be and the hole on top is drilled by myself or yourself. Countersink the top a little so that it forms a funnel to catch oil from the splash. It works perfect. ie. there will be no bush. Does your pistons look like these?

What is the condition like on the other goods? The pistons, crank, sleeves etc. Can you measure the thickness of the head as well? That will be from the bottom where the gasket is to the top where the rocker cover sits. It will be around 70 something mm.

You can start your stock taking now and do a dummy assembly to see what is short.

[stcos85]

I need to buy pistons and liners from meca parts but now i know the rods can be used without bushes i can move forward