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Author Topic: 1.6 turbo diesel con rods... how much boost will they take?  (Read 6258 times)

May 30, 2012, 06:30:18 pm

tomsdubwerks

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After stripping my GTD project engine and finding two bent rods I'm wondering how much boost the stock rods will handle?


Drives '77 Polo 1.4 16v on ITB's
            '90 Caddy Pickup 1.6 NA... Eventually 1.6TD

Reply #1May 30, 2012, 08:22:56 pm

R.O.R-2.0

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Re: 1.6 turbo diesel con rods... how much boost will they take?
« Reply #1 on: May 30, 2012, 08:22:56 pm »
After stripping my GTD project engine and finding two bent rods I'm wondering how much boost the stock rods will handle?

more than the head will take..
92 Jetta GLI - Black, 1.6D w/ GT2056V turbo..
86 GTI - 4 Door, Med Twilight Gray, Tow Machine..
86 Audi Coupe GT - Tornado Red, All Stock.. WRECKED.
89 Toyota 4Runner - Dark Grey Metallic, LIFTED!

Turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster.

Reply #2May 30, 2012, 10:11:51 pm

libbydiesel

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Re: 1.6 turbo diesel con rods... how much boost will they take?
« Reply #2 on: May 30, 2012, 10:11:51 pm »
Probably bent from the coolant pouring into your cylinders.

Reply #3May 31, 2012, 12:12:36 am

R.O.R-2.0

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Re: 1.6 turbo diesel con rods... how much boost will they take?
« Reply #3 on: May 31, 2012, 12:12:36 am »
Probably bent from the coolant pouring into your cylinders.

or very bad valve contact..
92 Jetta GLI - Black, 1.6D w/ GT2056V turbo..
86 GTI - 4 Door, Med Twilight Gray, Tow Machine..
86 Audi Coupe GT - Tornado Red, All Stock.. WRECKED.
89 Toyota 4Runner - Dark Grey Metallic, LIFTED!

Turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster.

Reply #4May 31, 2012, 04:10:17 am

tomsdubwerks

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Re: 1.6 turbo diesel con rods... how much boost will they take?
« Reply #4 on: May 31, 2012, 04:10:17 am »
Probably bent from the coolant pouring into your cylinders.

or very bad valve contact..

Coolant causing hydraulic lock was on my mind given the state of the gasket. Valves don't appear to have touched the pistons but will get a good once over to be sure. I wasn't going to rule out it it running away on its own engine oil due to the twisted and collapsed oil return and the amount of oil in the turbo itself. 
Drives '77 Polo 1.4 16v on ITB's
            '90 Caddy Pickup 1.6 NA... Eventually 1.6TD

Reply #5May 31, 2012, 04:43:40 am

tomsdubwerks

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Re: 1.6 turbo diesel con rods... how much boost will they take?
« Reply #5 on: May 31, 2012, 04:43:40 am »
Also stumbled across a thread claiming that the stock rods will take 290ft/lbs of torque without issue. They certainly look nice and strong but I'm used to petrol engine ones. I should imagine 20-25psi of boost is not a problem for them?
Drives '77 Polo 1.4 16v on ITB's
            '90 Caddy Pickup 1.6 NA... Eventually 1.6TD

Reply #6May 31, 2012, 05:35:55 am

Alcaid

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Re: 1.6 turbo diesel con rods... how much boost will they take?
« Reply #6 on: May 31, 2012, 05:35:55 am »
The worry-free solution i have chosen:



http://rosten-performance.com/

As a general rule I would say if you are going to run a wastegated turbo, stock is good. A VNT with active vane control, H-beam rods (and a block girdle) may be needed.
'03 VW Golf PD130 4Motion Highline
'10 VW Passat 1.6TDI Highline
'83 VW Jetta 1.6TD, 11mm pump, H-beam rods, girdle, fully reworked AAZ head +++ Going Compound ;)

Reply #7May 31, 2012, 01:15:57 pm

R.O.R-2.0

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Re: 1.6 turbo diesel con rods... how much boost will they take?
« Reply #7 on: May 31, 2012, 01:15:57 pm »
Also stumbled across a thread claiming that the stock rods will take 290ft/lbs of torque without issue. They certainly look nice and strong but I'm used to petrol engine ones. I should imagine 20-25psi of boost is not a problem for them?

i ran north of 35psi (closer to 40psi) to a 1.5D engine, before the head let go..

i tell you, the RODS are not the weak point. the head is. the bottom end will take whatever you throw at it.

hell, i was making 20psi around 2500 revs the other day, ~half throttle or so.. and my engine still runs. they almost never see those kinda boost pressures down that low..

my experience is with VNT turbos tho, and they make lots of boost down low.. conventional turbos usually run more restricted flow tho, so dont expect those numbers with a conventional turbo..

so, again.. the HEAD is the weak point of IDI engines.. not the bottom end. the rods will compress anything that can be compressed..
92 Jetta GLI - Black, 1.6D w/ GT2056V turbo..
86 GTI - 4 Door, Med Twilight Gray, Tow Machine..
86 Audi Coupe GT - Tornado Red, All Stock.. WRECKED.
89 Toyota 4Runner - Dark Grey Metallic, LIFTED!

Turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster.

Reply #8May 31, 2012, 08:15:16 pm

bugnut

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Re: 1.6 turbo diesel con rods... how much boost will they take?
« Reply #8 on: May 31, 2012, 08:15:16 pm »
I bent my rods and was only pushing 30 to 35psi with my twin setup. it didn't like to run too well at an idle. tore it down and found 3 rods were bent. Two were sitting below the deck. I think it had to do with my intake setup but still possible to bend the rods. Now I am running Pauter X beams.
1980 Rabbit  1.9/1.6 franko engine.  compound built in the works

Reply #9May 31, 2012, 10:35:12 pm

theman53

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Re: 1.6 turbo diesel con rods... how much boost will they take?
« Reply #9 on: May 31, 2012, 10:35:12 pm »
When they bent, did you have to scrap the block, pistions, and rings, or did you just put new rods and rod bearings in the same bore and all was well? I have been thinking of upgrading rods, but money is money :D

Reply #10June 01, 2012, 02:22:10 am

Alcaid

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Re: 1.6 turbo diesel con rods... how much boost will they take?
« Reply #10 on: June 01, 2012, 02:22:10 am »
i ran north of 35psi (closer to 40psi) to a 1.5D engine, before the head let go..

i tell you, the RODS are not the weak point. the head is. the bottom end will take whatever you throw at it.

hell, i was making 20psi around 2500 revs the other day, ~half throttle or so.. and my engine still runs. they almost never see those kinda boost pressures down that low..

my experience is with VNT turbos tho, and they make lots of boost down low.. conventional turbos usually run more restricted flow tho, so dont expect those numbers with a conventional turbo..

so, again.. the HEAD is the weak point of IDI engines.. not the bottom end. the rods will compress anything that can be compressed..

There is a lot more factors to Peak Cylinder Pressure than just boost. Fuel and boost it like crazy on low RPMs and see if your rods can take the beating. ;)
'03 VW Golf PD130 4Motion Highline
'10 VW Passat 1.6TDI Highline
'83 VW Jetta 1.6TD, 11mm pump, H-beam rods, girdle, fully reworked AAZ head +++ Going Compound ;)

Reply #11June 01, 2012, 05:27:36 am

tomsdubwerks

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Re: 1.6 turbo diesel con rods... how much boost will they take?
« Reply #11 on: June 01, 2012, 05:27:36 am »
Those Rosten rods look awesome. Thanks guys I'll be running a conventional turbo or maybe an Eaton supercharger with sensible boost levels for daily reliability. Fairly confidant stock will be fine for me after reading your experiences. My spare N/A gave up it's crank and roads last night for the TD. Just need to clean them up and measure up.
Drives '77 Polo 1.4 16v on ITB's
            '90 Caddy Pickup 1.6 NA... Eventually 1.6TD

Reply #12June 01, 2012, 08:29:22 pm

bugnut

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Re: 1.6 turbo diesel con rods... how much boost will they take?
« Reply #12 on: June 01, 2012, 08:29:22 pm »
When they bent, did you have to scrap the block, pistions, and rings, or did you just put new rods and rod bearings in the same bore and all was well? I have been thinking of upgrading rods, but money is money :D

I just put new rods in and called it good. I even used the old rod bearings. I really wouldn't call them old. They only had maybe a 1000 miles on them.  I checked them over and platsigauge them in a few spots and all was well. Still running good till this day. I'd say I have about 7,000 to 8,000 on it now and I still beat that poor engine up.
1980 Rabbit  1.9/1.6 franko engine.  compound built in the works