1.7 VS 1.8 Engine Rebuild .. |
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1.7 VS 1.8 Engine Rebuild .. |
Beakster |
Aug 1 2018, 10:22 PM
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#1
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Member Group: Members Posts: 121 Joined: 13-August 15 From: Calgary,AB Canada Member No.: 19,055 Region Association: None |
Hi Guys .. I'm being told that it is better to rebuild a 1.8 to get more torque from the engine then rebuilding the 1.7 .. and even the 2.0 casing .. would love a 2.0 but they are getting harder to find .. Is this TRUE ... If I should look for a 1.8 then spend too much $$$ in my 1.7 .. What's your thoughts ... ???
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McMark |
Aug 2 2018, 04:23 AM
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#2
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
All the engine cases are the same.
Cranks: The 1.7 and 1.8 have the same 66mm stroke. The 2.0 has a 71mm stroke. You can purchase crankshafts with longer stroke, such as 78mm and 80mm. But these make the engine build more complicated. Any of these cranks will fit in any engine case. Pistons: The 1.7 had 90mm pistons. The 1.8 had 93mm pistons. The 2.0 had 94mm pistons. The MOST common rebuild option, for nearly ANY engine, is to install 96mm pistons. There's different versions for 66mm cranks and 71mm or larger cranks. Heads: Stock 1.7 heads shouldn't be used in an upgraded engine. Stock 1.8 heads are okay, but really shouldn't be used in an upgraded engine. Stock 2.0 heads shouldn't be rebuilt anymore. AAPistons 2.0 replica heads should be purchased bare and built by someone knowledgeable. (skimp on other parts and spend money here if you're on a budget) But here's the real questions... What do you have now? What are you trying to accomplish? What's your budget? |
Dave_Darling |
Aug 2 2018, 09:12 AM
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#3
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914 Idiot Group: Members Posts: 15,063 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
I'm not sure about the 1.7 or 1.8 heads not being used in any upgraded engine... I would think they would be OK for mild upgrades, particularly the 1.8 heads.
The 1.7 heads have 100mm "registers"--where the top of the cylinder fits into the head. The 1.8 and 2.0 heads have 104mm (105?) registers. There are 96mm cylinders that fit into the 1.7 heads, but the tops will be less than 2mm thick. Not a great idea for longevity. Far better to use the 96mm cylinders that are intended for 1.8 or 2.0 heads. You get a 1911cc motor when you use the 66mm stroke with 96mm P&Cs. It's a nice modest upgrade... --DD |
Beakster |
Aug 4 2018, 08:08 PM
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#4
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Member Group: Members Posts: 121 Joined: 13-August 15 From: Calgary,AB Canada Member No.: 19,055 Region Association: None |
All the engine cases are the same. Cranks: The 1.7 and 1.8 have the same 66mm stroke. The 2.0 has a 71mm stroke. You can purchase crankshafts with longer stroke, such as 78mm and 80mm. But these make the engine build more complicated. Any of these cranks will fit in any engine case. Pistons: The 1.7 had 90mm pistons. The 1.8 had 93mm pistons. The 2.0 had 94mm pistons. The MOST common rebuild option, for nearly ANY engine, is to install 96mm pistons. There's different versions for 66mm cranks and 71mm or larger cranks. Heads: Stock 1.7 heads shouldn't be used in and upgraded engine. Stock 1.8 heads are okay, but really shouldn't be used in an upgraded engine. Stock 2.0 heads shouldn't be rebuilt anymore. AAPistons 2.0 replica heads should be purchased bare and built by someone knowledgable. (skimp on other parts and spend money here if you're on a budget) But here's the real questions... What do you have now? What are you trying to accomplish? What's your budget? This is what I have ... The engine in the car is seized it has a 1.7 case but I have been told by the PO that the engine was rebuilt but has sat for 6 years .. What he told me was It has new pistons , Full advance distribitor and dual 44 webers .. he said something about a 2.0 But I don't think it is the heads because they are not 3 bolt on the top ... I'm going to try to UNseize the engine But without pulling the engine out to see WTF I have I can't go on what the PO told me ... i'm going to keep the carbs But I don't Know where to go from there .. I'm looking for a torquee engine Not real fast like 6cyl .. But I love the feedback .. THANKS |
McMark |
Aug 5 2018, 07:44 AM
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#5
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
I had a motor (from back when I was JUST getting into cars) that I put new rings on. Ran it only a few 100 miles and parked it for awhile. The new rings and the cylinders were still breaking in, so they were still scraping each other and exposing bare metal. When I parked it, condensation probably caused corrosion. There wasn't enough oil residue built up to prevent it. Tried everything to break it free and had no success.
I would suggest that even if you do manage to break it free, assume it's damaged, at least slightly. I would suggest disassembling it and seeing what you have, then making a plan. But don't do anything unless you're prepared to spend at least $2k on the build. And if you're upgrading components, it can easily rise to $5k-$7k -- more if you've having a shop do the work. |
burton73 |
Aug 5 2018, 11:51 AM
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#6
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burton73 Group: Members Posts: 3,692 Joined: 2-January 07 From: Los Angeles Member No.: 7,414 Region Association: Southern California |
This is a brand new, Cylinder Head for a VW Type 4 2.0L The head comes with Intake and Exhaust Valves, with Keepers, retainers, and springs. Its ready to install. The Head tapped for the head temp sensor
$440. is this the right starting part for us. Bob B |
r_towle |
Aug 5 2018, 03:05 PM
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#7
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Custom Member Group: Members Posts: 24,661 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
Pour marvel mystery oil in each cylinder via the spark plug hole , leave plug out.
Put car in fifth, Tow car backwards then forward with another car. It will eventually give up. Then dump the oil, put in cheap oil ( you will change it a few times) Fire it up. Get it warm check compression. |
mb911 |
Aug 5 2018, 03:36 PM
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#8
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914 Guru Group: Members Posts: 7,369 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest |
Pour marvel mystery oil in each cylinder via the spark plug hole , leave plug out. Put car in fifth, Tow car backwards then forward with another car. It will eventually give up. Then dump the oil, put in cheap oil ( you will change it a few times) Fire it up. Get it warm check compression. Thats what dad did on his and broke it free. Listened to it run for the 1st time in 10 or so years last week. |
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