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TurboTwinSpark Guide for Noobs

10K views 49 replies 16 participants last post by  Gertie 
#1 ·
Hello! I have some skills of turbocharging my jts\ts and i want to show all what i know and what i done.

First of all we need to make low compression ratio. I didnt have much money for Woessner pistons and i have ideas to cut from stock pistons some meat.

I cut 2mm from each pistons. Later i balance it with rods and pins
 

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#2 ·
I found on Allegro in Poland cheap(30USD) exhaust manifold from 156 1.9JTD and cut flange. And weld needed flange.
It very good weld with MIG welding tool.
 

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#13 ·
Looks good
 
#25 ·
How much clearance is there between the piston and the head on a cf2 engine ?
A few weeks ago I was talking with somebody about the possibility of fitting a cf3 gasket ond a cf1/2 engine. Ofcourse we know that you just can't use the cf3 gasket because the pistons will hit the head. We were thinking to skim 1 mm of the cf2 piston and use a cf3 gasket to raise compression.
ACAB said that the cf2 gasket is 1,9mm and the cf3 is 0,4mm. So if you use a 0,4 mm gasket you win 1,5mm but that's clearly to much. But how much is enough to clear the piston from the head ? If you skim 1 mm from the piston you win 0,5mm...
 
#27 ·
#28 ·
Okay, so what would be a safe setup ?

You raced with 2x0,4 so 0,8 which is 1,1 less than with standard gasket. 0,8 is clearly not enough, so 1 (or more) would be safer. When I use one 0,4 gasket and skim 0,6 from the pistons that would make 1mm in total and 0,9mm more compression. Is that safe enough or is more space needed ? I don't know what the compression would be, I have to calculate that when I'm home tonight...
 
#29 ·
Just a remark.
1mm conrod extension at usual (say below 8000rpm) RPMs seems to me HUGE. Because of all the problems related to piston guided conrods and fast bearing wear I wonder if this accident could not be due to worn bearings ?

The other point is that the head squish areas are 1.5-2mm higher than the not skimmed head floor. I believe on the 2.0 engine pistons are just 1mm bigger than the chamber so this 1mm circle could be machined to prevent any contact.
 
#45 ·
First head gasket change, they gave me the wrong head gasket, thought it was a factory upgrade, but it wasn't.

So my engine was noisy as hell and i thought it were the hydraulic lifters but it wasn't.

When i dismantle the head again i was able to see that the pistons were hitting the head gasket, no damage to the valves, valves didn't touch anything, but pistons marked the head gasket rings!!!

But please can someone tell me if the water jackets will hit the jtd exhaust manifold?!

Regards
 
#47 ·
Can i dare to ask what ECU management is used, because hardware can be adapted more easily(my point of view) than ECU management.
Injector sizes, and so on?????
 
#50 · (Edited)
I ran 100% fuel duty cycle at 0.3bar (4.5psi) with stock injectors and (rather old) stock pump. I sacrificed a head gasket in finding the problem. I now bought a walbro style 255 L/hr pump ; cut open the OEM pump assembly to fit and saw the filter gunked up was the main culprit for low fueling. I am agreeing that stock setup is OK for low boost, just make sure pump is not too old / fouled up
 
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