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Engine Specific Info and Questions => IDI Engine => Topic started by: silentdub on March 11, 2011, 11:12:32 am

Title: 1.6 Compression Specs and question
Post by: silentdub on March 11, 2011, 11:12:32 am
I am about to tear down this 1.6 and send it off to the machine shop. I will have the head resurfaced as well as the block. I am wondering what the current spc is for this motor 20:1?

I am guess it is about 20:1, would anyone recommend bumping it up to say 20.5 or 21 for a little more power or is this not a good idea?

For those that changed it, how much did you shave off the head?

2nd question, Oil squirters, are they standard on the 1.6? Should I add/install them if not?

This is a non turbo and I am keeping it that way.
Title: Re: 1.6 Compression Specs and question
Post by: bajacalal on March 11, 2011, 12:42:30 pm
Factory specs on this thing are something around 22.5 to 1. That's a lot of pressure, even for a diesel. I don't see how much more you could get away with, these are EXTREME interference motors with little room to spare, the valves when closed sit like 0.30" from the piston top at TDC. You might need to use of a thicker head gasket if material is removed from the block or head.

Oil squirters were standard on turbo blocks and I think VW started adding them to more engines later on, it wouldn't be a bad idea to add them if yours doesn't have them but not necessary on the NA. You might want to consider a higher volume oil pump if you add them.

Title: Re: 1.6 Compression Specs and question
Post by: R.O.R-2.0 on March 11, 2011, 12:46:44 pm
just leave it as it is.. VWs have some of the highest compression ive ever seen on a diesel..

oil squirters are not necessary,as was mentioned.. no n/a VW diesel 1.6 EVER got oil squirters that i know of.

only some of the industrial engines, and most of them were 1.7 and 1.9 blocks.
Title: Re: 1.6 Compression Specs and question
Post by: silentdub on March 11, 2011, 12:47:31 pm
Gotcha, so if there is no reason in increase compression, then so be it.

I would add the oil squirters, I hear that they really help keep the pistons cool, so I figure why not.

Thanks for the answers!
Title: Re: 1.6 Compression Specs and question
Post by: bajacalal on March 11, 2011, 01:01:37 pm
@ROR I was thinking of engines like the 2.0 gas.

@silendub It's not that there's no reason to do it, it's that it's not feasible. The engine design just prevents it without, I would imagine, having custom pistons or something made, which doesn't make economic sense. The way to make more power with these engines is a turbocharger.
Remember, things that affect performance in gasoline engines don't necessarily apply to a diesel.
Title: Re: 1.6 Compression Specs and question
Post by: silentdub on March 11, 2011, 01:11:30 pm
@ROR I was thinking of engines like the 2.0 gas.

@silendub It's not that there's no reason to do it, it's that it's not feasible. The engine design just prevents it without, I would imagine, having custom pistons or something made, which doesn't make economic sense. The way to make more power with these engines is a turbocharger.
Remember, things that affect performance in gasoline engines don't necessarily apply to a diesel.

understood. This is my first diesel engine rebuild, hence the reason I am asking questions. I am building a sipster so power isn't my goal, just MPG.

Is there are reason to use a thicker gasket and lower compression a little?
Title: Re: 1.6 Compression Specs and question
Post by: R.O.R-2.0 on March 11, 2011, 01:19:08 pm
if you want to make your engine a sipster, a thicker gasket is going to be counter-productive..

run the right gasket for your piston protrusion.. thats the only way its going to get you maximum MPGs..

you are not running loads of boost, or anything like that, and the compression is already stupidly high on these engines, so basically, you have no reason to need to have the compression at any other number than where it is at factory..

the squish and quench is important on these engines.. and the head gasket thickness determines that..
Title: Re: 1.6 Compression Specs and question
Post by: maxfax on March 11, 2011, 01:21:38 pm
I think it was bought up before that slightly lower compression could improve economy.. I remeber reading somewhere that the biggest reason for the stupid high compression was for easier starting when selling these things to the masses..  Wonder what an AAZ head would do for this combo..
Title: Re: 1.6 Compression Specs and question
Post by: silentdub on March 11, 2011, 02:02:09 pm
I think it was bought up before that slightly lower compression could improve economy.. I remeber reading somewhere that the biggest reason for the stupid high compression was for easier starting when selling these things to the masses..  Wonder what an AAZ head would do for this combo..


That can make sense, but ya know, the regular gasket will be fine then. I am not that familiar with the N/A Diesels so I figured I'd ask.

How about different cam profiles? Stay stock for MPG or is there a better choice?
Title: Re: 1.6 Compression Specs and question
Post by: R.O.R-2.0 on March 11, 2011, 02:32:35 pm
I think it was bought up before that slightly lower compression could improve economy.. I remeber reading somewhere that the biggest reason for the stupid high compression was for easier starting when selling these things to the masses..  Wonder what an AAZ head would do for this combo..


That can make sense, but ya know, the regular gasket will be fine then. I am not that familiar with the N/A Diesels so I figured I'd ask.

How about different cam profiles? Stay stock for MPG or is there a better choice?

heres what you should do if you want more mileage:

free flowing intake and exhaust systems.
good transmission
turn injection pump down
properly inflated tires
no more weight in the car then is absolutely necessary..

opening up the intake and exhaust will really make a big difference in power and economy.

if your car ever smokes black, you are getting bad mileage..
Title: Re: 1.6 Compression Specs and question
Post by: R.O.R-2.0 on March 11, 2011, 02:33:55 pm
I think it was bought up before that slightly lower compression could improve economy.. I remeber reading somewhere that the biggest reason for the stupid high compression was for easier starting when selling these things to the masses..  Wonder what an AAZ head would do for this combo..

VWs do start very easily compared to other similar IDI diesels. my datsun pickup needs the glow plugs to start it even if you just shut it off hot 10 mins ago..

and what about a AAZ head? on an n/a? that might be kinda cool?
Title: Re: 1.6 Compression Specs and question
Post by: silentdub on March 11, 2011, 03:43:43 pm
I think it was bought up before that slightly lower compression could improve economy.. I remeber reading somewhere that the biggest reason for the stupid high compression was for easier starting when selling these things to the masses..  Wonder what an AAZ head would do for this combo..

VWs do start very easily compared to other similar IDI diesels. my datsun pickup needs the glow plugs to start it even if you just shut it off hot 10 mins ago..

and what about a AAZ head? on an n/a? that might be kinda cool?


AAZ head? Don't currently have one nor the money to invest in it.
Title: Re: 1.6 Compression Specs and question
Post by: rabbitman on March 11, 2011, 06:46:25 pm
The compression ratio for the 1.6D is 23:1 and the 1.5D is 23.5:1.

There's other option for cams and that's through Giles, they're call high performance but they'll probably get you better mileage too.
Title: Re: 1.6 Compression Specs and question
Post by: trav1856 on March 11, 2011, 09:26:57 pm
I was old anything over 6lbs boost on an NA engine will melt the rings. Anyone confirm?
Title: Re: 1.6 Compression Specs and question
Post by: R.O.R-2.0 on March 12, 2011, 08:44:46 am
I was old anything over 6lbs boost on an NA engine will melt the rings. Anyone confirm?

no, i cant confirm it, but i can tell you its un-true as hell.. i run around 20 psi to my n/a all the time.
Title: Re: 1.6 Compression Specs and question
Post by: maxfax on March 12, 2011, 08:50:56 am
Too much fuel is what melts things..   Too much boost just plays hell on the head sealing to the block..  Ask Kevin how he knows that..  ;D
Title: Re: 1.6 Compression Specs and question
Post by: R.O.R-2.0 on March 12, 2011, 09:44:07 am
Too much fuel is what melts things..   Too much boost just plays hell on the head sealing to the block..  Ask Kevin how he knows that..  ;D

what he said ;D
Title: Re: 1.6 Compression Specs and question
Post by: silentdub on March 15, 2011, 10:57:18 am
The compression ratio for the 1.6D is 23:1 and the 1.5D is 23.5:1.

There's other option for cams and that's through Giles, they're call high performance but they'll probably get you better mileage too.


Sweet, I'll look in to that. Going to pick up another engine stand today so I can tear it down. Time is really thin with me at the moment.



Who sells cams for the 1.6?
Title: Re: 1.6 Compression Specs and question
Post by: R.O.R-2.0 on March 15, 2011, 11:17:21 am
The compression ratio for the 1.6D is 23:1 and the 1.5D is 23.5:1.

There's other option for cams and that's through Giles, they're call high performance but they'll probably get you better mileage too.


Sweet, I'll look in to that. Going to pick up another engine stand today so I can tear it down. Time is really thin with me at the moment.



Who sells cams for the 1.6?

the quote you quoted, has your answer, lmfao..

Giles is his name BTW..
Title: Re: 1.6 Compression Specs and question
Post by: mystery3 on March 15, 2011, 10:57:41 pm
I was old anything over 6lbs boost on an NA engine will melt the rings. Anyone confirm?

How can you tell the rings melted when they're fused with all the surrounding bits? 

 
Title: Re: 1.6 Compression Specs and question
Post by: maxfax on March 16, 2011, 12:55:33 am
Typically the rings don't melt first, the piston does..   You'll be able to see obvious damage to the piston..
Title: Re: 1.6 Compression Specs and question
Post by: regcheeseman on March 16, 2011, 03:11:39 am
Quote from:  R.O.R-2.0
but i can tell you its un-true as hell.. i run around 20 psi to my n/a all the time.

Do you run squirters in this motor, I'm asking because of my knocking TD that has just been installed and the previously fitted perfectly good NA is sat on the floor. I've not used the NA because of the lack of squirters.
Title: Re: 1.6 Compression Specs and question
Post by: silentdub on March 16, 2011, 07:21:09 am
The compression ratio for the 1.6D is 23:1 and the 1.5D is 23.5:1.

There's other option for cams and that's through Giles, they're call high performance but they'll probably get you better mileage too.


Sweet, I'll look in to that. Going to pick up another engine stand today so I can tear it down. Time is really thin with me at the moment.



Who sells cams for the 1.6?

the quote you quoted, has your answer, lmfao..

Giles is his name BTW..




Sorry, I never heard og Giles and I was looking for a link. I'll google it.

thnaks!
Title: Re: 1.6 Compression Specs and question
Post by: silentdub on March 16, 2011, 07:27:46 am
Found it! http://www.vwdiesel.net/forum/index.php?topic=25574.0;wap2



Title: Re: 1.6 Compression Specs and question
Post by: R.O.R-2.0 on March 16, 2011, 08:26:34 am
Quote from:  R.O.R-2.0
but i can tell you its un-true as hell.. i run around 20 psi to my n/a all the time.

Do you run squirters in this motor, I'm asking because of my knocking TD that has just been installed and the previously fitted perfectly good NA is sat on the floor. I've not used the NA because of the lack of squirters.

im running a n/a.. (it came out of a vanagon, and they NEVER came with turbos that i know of.)

if it had squirters, i would call it a TD..

its a 11mm n/a block.. stock fiber head gasket..

the key to not burning these engines down, is not about keeping low boost, its about keeping the fuel in check with the right amount of air. thats why i can get away with 20+ psi.. i have enough air in there to keep the burn nice and lean.

Title: Re: 1.6 Compression Specs and question
Post by: rabbitman on March 16, 2011, 12:49:14 pm
im running a n/a.. (it came out of a vanagon, and they NEVER came with turbos that i know of.)

Yup they did, look on ebay, someone usually trying to sell a TD vanagon engine.........
Title: Re: 1.6 Compression Specs and question
Post by: silentdub on March 23, 2011, 10:36:33 am
Well, I'm encouraged now..... after some reading I see that this motors are soolid for the most part.


Can't wait to rebuild this little guy.
Title: Re: 1.6 Compression Specs and question
Post by: R.O.R-2.0 on March 23, 2011, 10:44:27 am
im running a n/a.. (it came out of a vanagon, and they NEVER came with turbos that i know of.)

Yup they did, look on ebay, someone usually trying to sell a TD vanagon engine.........

theres someone on craigslist selling a TDI-m from a vanagon..

and i meant that MY engine never came with a turbo..

its a CS code engine.. not turbo'd
Title: Re: 1.6 Compression Specs and question
Post by: sdwarf36 on March 23, 2011, 06:24:45 pm
FYI-surfacing the head will raise your compression ratio zero-its already flat. And if you surface the block .010 (DON"T!) you would only be raising CR by maybe .2.(21.0 to 21.2) And your piston + valves are closest at (apx) 8* before tdc for the exhaust-and (apx) 8* after tdc for intake.