performance increase 1300

You're right Steve, I seem to have a hard time sticking to the plan.
As you mention the main reason is Martijn :happy:
Not so much to compete, but Martijn keeps getting new tuning ideas.
As we live close to each other, I get the left overs :wink2:

Hahah...yes, don't start about the valves.
New pistons are not in the plan.
Although the spare block gives the possibility to skim it level.
Hope the bores are okay and only need honing.
 
honing is al you need:
honing.jpg

:laugh::laugh::laugh::laugh::laugh::laugh::laugh::laugh:
 
Paul,

with the stock pistons you'll still have the 5cc flycuts...the stock pistons are around 34.45CH so you'll be skimming around 0.5mm...

Loose those and go to small flycut pistons, which come in at 34.7 and also 34.9CH, and then skim the block to get them at zero...then your pushing close to 10:1.

It will better suit a longer duration cam... otherwise you'll be struggling to get over 9.4:1 static CR and your dynamic CR will suffer if you extend the valve open time...

Brian,

I don't own a video camera, but give me some time to set the bench and my testing rig up and sure...I'll find someone to shoot some digital footage of a head under test to show everyone what goes into getting a port to "work" ... 2010/2 and 2010/3 are booked in to Leon to have seat cuts and valve back cuts at the end of the month...then they are ready for testing...I guess that means I'll have to shave and get a haircut for my film debut :hmm:

SteveC
 
When going on camera: always wear a moustache...much cooler :cool:

Time to change the plan again and invest in some new pistons :wink2:
I like the idea of using standard parts to save a little money.
Same reason I probably will use a standard euro 1500 camshaft.

Trying to find out if the 1300 pistons are still available over here and what the cost would be.
Is this what I'm looking for: Mahle P/N 0078000, CH of 34.7mm with flycuts 2.6mm deep, dome height 0.6mm, crown shape type 4, overall length 77.3mm. Standard size 86.0mm, oversizes 0.2,0.4,0.6,0.8 and 1.0mm.
Not sure about the part number for 34.9 CH: 0087300 or 0087400?
I got it from an older post.
 
Mahle P/N 0078000,
CH of 34.7mm with flycuts 2.6mm deep,
dome height 0.6mm,
crown shape type 4,
overall length 77.3mm.
Standard size 86.0mm,
oversizes 0.2,0.4,0.6,0.8 and 1.0mm.

Mahle P/N 0087400,
CH of 34.9mm, with flycuts 2.7mm deep,
flat top piston,
crown shape type 3,
overall length 74.4mm.
Standard size 86.4mm,
oversizes 0.2,0.4 and 0.6mm.

If you get stuck I have 86.8's in both types.

Brian's engine is basically that spec...1500cc/flat top-small flycut/euro 1500 cam/euro inlet manifold/34dmtr-21/twin out exhaust manifold/37.5mm inlets/28.5mm port ... and he's quite pleased with the result.

SteveC
 
Steve in general you advise to get the pistons level.
Would it be an alternative to let the pistons protrude to get 10:1 compression?
I calculate with the standard pistons protruding 0,6mm and a FelPro crushed to 1,5mm exact 10:1.
 
If the pistons are popping up 0.6mm, and your using a felpro gasket which crushes down to around 1.5mm...your at the tight end of piston / head clearance for a street engine at 0.9mm, but still OK.

But that would mean taking over 1mm off the deck height, effectively weakening the head deck....and altering the cam timing / affecting cambelt tension at the same time....you would also need to check head bolts didn't bottom out and that head locating dowels didn't bottom out either, but sure it would be possible ... not the best engineering solution though IMO.

Surely a set of new pistons isn't that expensive or difficult to come by? And would give you the best possible piston to bore clearance and a fresh / round / untapered bore to bed in the new rings, and fresh flat ring lands in the pistons to keep the rings square...the same can't be said about honing and re ringing...

Getting more charge into the cylinders is wasted if it all leaks past poorly sealing rings.

SteveC
 
Finally got to use the special tool to remove the head off the spare engine.
It's mounted instead of the camshaft housing.



Really helpful to persuade the head to let go.
The head came loose, but didn't want to come off.
At the left corner the stud seems to become one with the head.
Finally the head came off...but at the price of destroying the head.



It seemed the previous owner used a bold to mount the exhaust manifold.
This bold reached the stud and was broken off.
Just drilling the broken bolt out was not enough.



I was glad to see clean bores inside.
Also happy to have a spare engine...don't want to think about the original idea to change heads over the weekend.

Fun tip.
The engine stand has a U-frame.
By accident I found out a water leak tray for washing machines fits perfectly in the U-frame.

 
Found a set of pistons with small cut outs.
It was a bit harder to find as expected.
Mahle does no longer have available the 1500 pistons and the 1300 are special order.
Bought a NOS set original oversize 86,8 pistons, with #7642421.



The Mahle catalog states as an alternative 0087300.
Most probably this should be 0087400 by Steve’s definition it is a type 3 piston.
Measured the cut outs at approx. 0,7cc.

Measured also the piston to deck height with the original pistons…surprised to see it was only 0,1mm.
If the original pistons have a CH of 34,45, the new pistons will stick out 0,35mm
I’m getting a bit more compression as expected.
Calculation shows 10,5:1.

Earlier I was searching for thin head gaskets, but with these numbers a FelPro is just about right.
Compressed to 1,5mm, the squish will be a little over 1,1mm.
No need to deck the block.

In Europe we can fill the tank with euro91, euro95 or euro98.
Anybody know what the minimum is with a 10,5:1 compression?

The weight of the pistons is between 598 and 600 grams.
Is this something I should make equal?
 
Anybody know the compression height of the standard 1500 piston?

Looking for info, I found this scan.




From it I suspect the CH for the 1300 is standard 34,45 (bottom middle).
And for the 1500 the standard CH is 34,7 (top left).
This is based on the shape fly cut outs.

Steve could it be you mixed both earlier?
 
Last edited:
Large flycut OE 1500 pistons are 34.45CH, the 128 rally/x19 1300 are small flycut 34.7CH, some uno 1300's are small flycut 34.9CH, and I have both large and small flycut pistons in 34.15CH....

I have that page you've scanned in an X19 1500 parts catalogue, and I think the dimensions listed are incorrect...opposite page are some notations and they are mixed up...when compared to Mahle/ Kolben Schmidt/ Borgo/ Mondial piston catalogues

SteveC
 
paul said:
In Europe we can fill the tank with euro91, euro95 or euro98.
Anybody know what the minimum is with a 10,5:1 compression?
Click to expand...

Good news...from Ulix I learned he drives with 11:1 compression and uses Euro98 on his awesome trips around Nürburgring...in theory we're still okay ;)
 
I second that and...

AN INTERESTING QUOTE​
​
IT'S UNWISE TO PAY TOO MUCH​
BUT IT'S WORSE TO PAY TOO LITTLE.​

WHEN YOU PAY TOO MUCH YOU LOSE A LITTLE​
MONEY – THAT IS ALL.​

WHEN YOU PAY TOO LITTLE YOU SOMETIMES LOSE​
EVERYTHING BECAUSE WHAT YOU BOUGHT WAS​
INCAPABLE OF DOING THE THING IT WAS​
BOUGHT TO DO.​

THE COMMON LAW OF BUSINESS BALANCE​
PROHIBITS PAYING A LITTLE AND GETTING A​
LOT – IT CAN'T BE DONE.​

IF YOU DEAL WITH THE LOWEST BIDDER IT IS​
WELL TO ADD SOMETHING FOR THE RISK YOU RUN.​

AND IF YOU DO THAT, YOU WILL HAVE ENOUGH​
TO PAY FOR SOMETHING BETTER.​

By:​
John Ruskin​
Essays on Political Economics​
J. Wily - 1886​
 
Not planning on selling bare heads, only complete assembled (with valves / springs) and CNC ported units, still in progress...still flow testing different configurations.

SteveC
 
Time frame

Hello Steve,
Any idea on your time frame for those heads? No rush, I know how this stuff can take a while.
Bob
 
Hi Bob,

unfortunately life and work keeps getting in the way of my hobby!!

The wife is still very ill, the tumours have re appeared in her brain and she's undergoing a new trial chemo drug, which seems to be keeping the nasties at bay, so fingers crossed...and I've been spending as much time with her as possible.

Plus work has been busy with the installation and commissioning of a new pumping station as well as a new fire deluge system for the new underground explosives magazine...that's all just about done so things should slow down and I'll be back to my normal roster and having more time to play Fiats.

Basically the flow bench is up and running, but it is such a time consuming job, and I've only had two weeks off in the last 9 weeks...instead of my usual week on / week off roster...so the CNC test head is still under development...so it won't happen overnight, but it will happen...my best guess is by the end of the year I'll have some heads to sell.

SteveC
 
Steve

sorry about your wife. Hope some of this new treatment will work.

I realize that family is the priority at the moment. I am patient and definitely can wait until end of the year for the new engine build.

Best wishes,
 
paul said:
On xweb 1.0 there are some interesting posts by Steve Hoelscher.
He drives his hot 1300 with a FAZA 35/75.
Although I couldn't find the exact specs of this cam, I suspect it's close to the 1500 euro cam.
Click to expand...

From Ulix I received this interesting diagram.
It shows different camshafts he has degreed.

Nockenkurven.png


The result comparing the grinds of the PBS SX1, PBS S2, FAZA 35/75, FAZA40/80 and Euro1500 is surprising.
Although the durations of the different cams varies from 272 to 300 degrees, the cams show very similar profiles.
The opening at TDC of the inlet and exhaust valves is a little higher for the FAZA40/80 and little lower for the Euro1500 cam.
 
You must log in or register to reply here.
Back
Top