NEED HELP on engine type/size, Previous owner's mods ???? |
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NEED HELP on engine type/size, Previous owner's mods ???? |
Str1974 |
Dec 17 2021, 01:50 PM
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#1
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Member Group: Members Posts: 90 Joined: 23-January 19 From: Dallas Member No.: 22,820 Region Association: Southwest Region |
Guys, I really need your expertise on this. I had purchased a 1974 914 1.8L a while back. The former owner advised me that the engine was not matching. Looks like a previous owner had taken a 1.7 liter case and modified it to be a 1.8L and use a Bosch L-jetronic brain as well as all the air intake/manifold designed for a stock 1.8L. It ran well before I pulled the engine for a new clutch/flywheel etc. project. I had verified that the chassis number matches a 1974 914 and the engine number matches a 1973 1.7L (EA026464).
My real problem now is that I really do not know what exactly was done to the engine to make it a 1.8L. I want to keep the L-jetronic fuel injection system, but if I do want to do a stock engine rebuild, what parts would be for a 1.7L and what would be for a 1.8L. I have researched all over about 1.7L engine mods, but they all seem to be "how to modify a 1.7/1.8 to a 2.0L. Nothing what would have been done to make a 1.7 into a 1.8. an anyone please fill me in on the Possible Mods done to my engine? I have various service records that go back to the mid 80's, but it looks like the 1.7 to 1.8 mod was done prior to that. All those records seem to only mention the car being a 1.8L. I'm afraid to replace parts , not knowing how it became a 1.8L. Please advise, thanks. |
914werke |
Dec 17 2021, 02:31 PM
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#2
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"I got blisters on me fingers" Group: Members Posts: 10,059 Joined: 22-March 03 From: USofA Member No.: 453 Region Association: Pacific Northwest |
The only thing different between a 73 1.7 & a 74 1.8L long block is Bore (P&C's).
Same 66mm crank. |
brant |
Dec 17 2021, 02:58 PM
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#3
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914 Wizard Group: Members Posts: 11,623 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains |
also... the common upgrade for a 1.8 (or 1.7) when you put larger cylinders in... comes out to 1911
so not really a 1.8 technically. you would put stock cylinders and pistons in to make it a 1.8 again or you could keep the larger displacement as it is likely a more powerful engine you would also want to see which heads are on yours when it is torn apart if they are 1.7 heads then I believe they would have slightly smaller valves than a 1.8 stock motor would have. the Air Fuel Ratio should be measured on a running engine to tell you whether your mixture is adjusted to handle a larger placement or whether you need to adjust the fuel injection system still |
Str1974 |
Dec 17 2021, 04:01 PM
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#4
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Member Group: Members Posts: 90 Joined: 23-January 19 From: Dallas Member No.: 22,820 Region Association: Southwest Region |
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DaveB |
Dec 17 2021, 04:10 PM
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#5
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Member Group: Members Posts: 163 Joined: 25-November 21 From: Portland, Oregon Member No.: 26,107 Region Association: Pacific Northwest |
I had verified that the chassis number matches a 1974 914 and the engine number matches a 1973 1.7L (EA026464). I believe that engine number falls into the 71/72 manufacturing time frame and was used in a '72 911/4. I'd suggest checking the transmission s/n to see if they swapped the drivetrain or swapped out just the engine. Around that time the transmissions went from the 914/11 to the 914/12. IMO the engine was not made into a 1.8, you probably have a 1.7 or 1.7 with larger cylinders. You can do a compression check to find out. If you are worried about replacing parts, wait for them to be replaced, pull it and see what you got. Seriously, don't overthink this. If it drives well, enjoy it. Once you start the idea of getting this to a stock 1.8 configuration, you'll start the process, realize you can make some improvements, add a little more power, and before you know it you'll drop $10K and still want more. DaveB |
Mark Henry |
Dec 17 2021, 04:10 PM
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#6
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
you would also want to see which heads are on yours when it is torn apart if they are 1.7 heads then I believe they would have slightly smaller valves than a 1.8 stock motor would have. You could pull a valve cover and rockers off and see what heads you have, you might have an 1.8 already. |
Str1974 |
Dec 17 2021, 04:12 PM
Post
#7
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Member Group: Members Posts: 90 Joined: 23-January 19 From: Dallas Member No.: 22,820 Region Association: Southwest Region |
also... the common upgrade for a 1.8 (or 1.7) when you put larger cylinders in... comes out to 1911 so not really a 1.8 technically. you would put stock cylinders and pistons in to make it a 1.8 again or you could keep the larger displacement as it is likely a more powerful engine you would also want to see which heads are on yours when it is torn apart if they are 1.7 heads then I believe they would have slightly smaller valves than a 1.8 stock motor would have. the Air Fuel Ratio should be measured on a running engine to tell you whether your mixture is adjusted to handle a larger placement or whether you need to adjust the fuel injection system still I keep thinking that if the fuel injection is L-Jetronic (computer brain has L-jet serial numbers), would the heads not have to be 1.8 in order for a L-jet intake manifold to work with that type of Bosch EFI? |
Str1974 |
Dec 17 2021, 04:24 PM
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#8
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Member Group: Members Posts: 90 Joined: 23-January 19 From: Dallas Member No.: 22,820 Region Association: Southwest Region |
you would also want to see which heads are on yours when it is torn apart if they are 1.7 heads then I believe they would have slightly smaller valves than a 1.8 stock motor would have. You could pull a valve cover and rockers off and see what heads you have, you might have an 1.8 already. I actually have the rockers off due to replacing leaking push rod tubes. How do I find out what the heads are? I don't seem to see any part numbers on my heads. |
brant |
Dec 17 2021, 04:26 PM
Post
#9
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914 Wizard Group: Members Posts: 11,623 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains |
also... the common upgrade for a 1.8 (or 1.7) when you put larger cylinders in... comes out to 1911 so not really a 1.8 technically. you would put stock cylinders and pistons in to make it a 1.8 again or you could keep the larger displacement as it is likely a more powerful engine you would also want to see which heads are on yours when it is torn apart if they are 1.7 heads then I believe they would have slightly smaller valves than a 1.8 stock motor would have. the Air Fuel Ratio should be measured on a running engine to tell you whether your mixture is adjusted to handle a larger placement or whether you need to adjust the fuel injection system still I keep thinking that if the fuel injection is L-Jetronic (computer brain has L-jet serial numbers), would the heads not have to be 1.8 in order for a L-jet intake manifold to work with that type of Bosch EFI? nope.. heads don't care about induction you can run any head... but the 1.7 head has the smallest valves. but you can run L-jet on a 1.7/1.8/2.0 or 2056 bigger valves help move more air.. more HP the 2.0 heads have the best flow and best design injection fuel flow needs to match the displacement to get to the correct AFR so many people will measure the AFR and adjust their injection system to accommodate their need on a particular engine.... |
914Mels |
Dec 17 2021, 05:06 PM
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#10
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Member Group: Members Posts: 357 Joined: 20-June 11 From: Santee Member No.: 13,221 Region Association: Southern California |
Guys, I really need your expertise on this. I had purchased a 1974 914 1.8L a while back. The former owner advised me that the engine was not matching. Looks like a previous owner had taken a 1.7 liter case and modified it to be a 1.8L and use a Bosch L-jetronic brain as well as all the air intake/manifold designed for a stock 1.8L. It ran well before I pulled the engine for a new clutch/flywheel etc. project. I had verified that the chassis number matches a 1974 914 and the engine number matches a 1973 1.7L (EA026464). My real problem now is that I really do not know what exactly was done to the engine to make it a 1.8L. I want to keep the L-jetronic fuel injection system, but if I do want to do a stock engine rebuild, what parts would be for a 1.7L and what would be for a 1.8L. I have researched all over about 1.7L engine mods, but they all seem to be "how to modify a 1.7/1.8 to a 2.0L. Nothing what would have been done to make a 1.7 into a 1.8. an anyone please fill me in on the Possible Mods done to my engine? I have various service records that go back to the mid 80's, but it looks like the 1.7 to 1.8 mod was done prior to that. All those records seem to only mention the car being a 1.8L. I'm afraid to replace parts , not knowing how it became a 1.8L. Please advise, thanks. Years back we turned our 1.7 into a 1.8 displacement engine. All you had to do was replace the 90mm p&c's with the 1.8 liter's 93mm and fly cut the heads to fit the bigger cylinders. There was a slip in 96mm option but the cylinder walls were very thin. |
Mark Henry |
Dec 17 2021, 06:48 PM
Post
#11
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
also... the common upgrade for a 1.8 (or 1.7) when you put larger cylinders in... comes out to 1911 so not really a 1.8 technically. you would put stock cylinders and pistons in to make it a 1.8 again or you could keep the larger displacement as it is likely a more powerful engine you would also want to see which heads are on yours when it is torn apart if they are 1.7 heads then I believe they would have slightly smaller valves than a 1.8 stock motor would have. the Air Fuel Ratio should be measured on a running engine to tell you whether your mixture is adjusted to handle a larger placement or whether you need to adjust the fuel injection system still I keep thinking that if the fuel injection is L-Jetronic (computer brain has L-jet serial numbers), would the heads not have to be 1.8 in order for a L-jet intake manifold to work with that type of Bosch EFI? I've built a couple of Ljets with 2.0 engines, they run good. Ljet was a more modern design than Djet. |
73-914 |
Dec 17 2021, 07:04 PM
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#12
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Senior Member Group: Members Posts: 575 Joined: 24-April 10 From: Albany UpstateNY Member No.: 11,651 Region Association: None |
Isn't the 76 912E L-jet?
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914werke |
Dec 17 2021, 07:55 PM
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#13
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"I got blisters on me fingers" Group: Members Posts: 10,059 Joined: 22-March 03 From: USofA Member No.: 453 Region Association: Pacific Northwest |
Yes (IMG:style_emoticons/default/smile.gif)
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