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B3owulf |
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#21
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Newbie ![]() Group: Members Posts: 45 Joined: 4-September 21 From: Clarksville TN Member No.: 25,879 Region Association: MidAtlantic Region ![]() ![]() |
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technicalninja |
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#22
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Senior Member ![]() ![]() ![]() Group: Members Posts: 1,807 Joined: 31-January 23 From: Granbury Texas Member No.: 27,135 Region Association: Southwest Region ![]() ![]() |
Leak downs on an engine that has been sitting for 6 months are almost always inaccurate. The longer it's sat the worse the reading are.
It's fine to do it but if you have some leakage, I'd write down the numbers and not worry about them. I've seen a cylinder that tests 60% clean up to low 90s after running it a bit. Super bad leakage shouldn't be ignored but a cylinder at 60% wouldn't bother me if it had sat for awhile. |
rgalla9146 |
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#23
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 4,610 Joined: 23-November 05 From: Paramus NJ Member No.: 5,176 Region Association: None ![]() ![]() |
Leak downs on an engine that has been sitting for 6 months are almost always inaccurate. The longer it's sat the worse the reading are. It's fine to do it but if you have some leakage, I'd write down the numbers and not worry about them. I've seen a cylinder that tests 60% clean up to low 90s after running it a bit. Super bad leakage shouldn't be ignored but a cylinder at 60% wouldn't bother me if it had sat for awhile. Absolutely correct. I've seen 911 engines come out of long dry storage with very low compression/leak down numbers. Rotate the engine by hand using compressed air to blow through each cylinder. Dont jump to adjust valves. Wait. Take youe time. Use common sense. I've seen very good recoveries. |
B3owulf |
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#24
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Newbie ![]() Group: Members Posts: 45 Joined: 4-September 21 From: Clarksville TN Member No.: 25,879 Region Association: MidAtlantic Region ![]() ![]() |
I have a small progress update. Unfortunately, I have been quite busy at work so have not made a ton of progress, just small stuff.
(IMG:https://i.ibb.co/0j67xTp/IMG-3398.jpg) Got the brakes installed and found that all four calipers leaked, looks like whoever rebuilt them pinched the o rings when assembling. So I learned how to rebuild calipers and now no leaks! (IMG:http://www.914world.com/bbs2/uploads_offsite/i.ibb.co-25879-1714913968.1.jpg) Sway bar is installed, had to do a lot of parts cleaning and replace bushings. (IMG:http://www.914world.com/bbs2/uploads_offsite/i.ibb.co-25879-1714913970.2.jpg) engine progress is slow. I'm trying to ensure I dont break anything as the parts are so expensive. I cleaned up the throttle bodies and checked for shaft play (none!). Did a leak down test and results were not so good. The air was escaping from the exhaust valves. I have it at a friends shop now we will see what we can do. I'm hoping it is just buildup on the valves keeping them from closing all the way. We will see (IMG:http://www.914world.com/bbs2/uploads_offsite/i.ibb.co-25879-1714913972.3.jpg) A local radiator shop cleaned out the fuel tank for me. (IMG:http://www.914world.com/bbs2/uploads_offsite/i.ibb.co-25879-1714913972.4.jpg) Sanded everything down and repainted it, just forgot to take an "after" picture. threw it straight in and plumbed it with tangerine racing fuel lines to the back. |
technicalninja |
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#25
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Senior Member ![]() ![]() ![]() Group: Members Posts: 1,807 Joined: 31-January 23 From: Granbury Texas Member No.: 27,135 Region Association: Southwest Region ![]() ![]() |
Two things.
1st: Something I missed on first read. "Component for sportomatic shifter". When I'm sourcing a core for a performance build, I WANT an "auto" version. Automatic vs manual the automatic will normally have 1/2 the "total revolutions" on the engine vs manual. Thrust wear is 10% auto vs manual. No clutch means no funky forward thrust on the bearings at every shift. Most automatics do not allow over-revving. Automatics are normally driven at less throttle angle. The automatic is designed for low rpm daily use. It's a SHITLOAD easier on the engine... As long as the basic parts are the same, I'll intentionally choose autos for my cores. #2 The leak down test with excessive airflow through the exhaust valves. What I will do when I have obvious leakage through a valve is to lightly tap the valve/rocker arm with a wooden dowel and a hammer. As the engine is at TDC you just barely want to "unseat" the valve and NOT bash the valve into the top of the piston. It makes a DISTINCT noise when done during a leak down. A pneumatic "BONK' is the best way to describe it. You WILL see the needle on the second gauge "flicker" big time. Sometimes the airflow itself "blows" the trash off of the valve/seat and your numbers can come up dramatically. Now, I don't think I could just install that engine... If I was already to the point you're at, I'd be pulling the heads/jugs at a minimum. I'd pull the valve springs and check valve to guide clearance. If bad that's a trip to the machine shop. If good you might be able to hand lap the valves in. I'd replace the rings and have the jugs plateau honed at the machine shop if the piston and cylinders were re-usable. I'd replace the valve springs too. At least two of those springs have been sitting "compressed" for however long the engine has sat, I would not trust them! Breaking a spring takes the valve and piston on that cylinder at a minimum. At high RPM it could be catastrophic and take EVERYTHING! Springs are cheap in my book. I consider them a "consumable" that should be replaced automatically on anything over 10 years old that you have apart. Normally, I'm hunting "improved" springs if available. Your children are cute! Enjoy them while you can. They will grow out of it quickly! Mine did... |
B3owulf |
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#26
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Newbie ![]() Group: Members Posts: 45 Joined: 4-September 21 From: Clarksville TN Member No.: 25,879 Region Association: MidAtlantic Region ![]() ![]() |
Thank you for the input! I have tomorrow off of work and plan on spending the day at my friends shop tinkering and now I have a plan for the time!
This forum is great for practical input like this. I definitely want to work with what I have as much as possible. |
B3owulf |
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#27
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Newbie ![]() Group: Members Posts: 45 Joined: 4-September 21 From: Clarksville TN Member No.: 25,879 Region Association: MidAtlantic Region ![]() ![]() |
We did have some success with "fixing" the exhaust valves however my friend and I agreed the engine needs the heads off for valve springs at a minimum, and probably machine work if we couldn't clean it up with lapping. I almost want to try running it as is but thats a bit more corner cutting than I am comfortable with.
I am a bit concerned I will sink a lot of time and money into the long block only to find a need for more time and money in the MFI system. I might be better off selling it as a core and keeping an eye out for a "normal" engine. I think for now I will focus on getting the car on the road with the four cylinder. I want to keep momentum on the project while I have some time available. I can get the car driving and have some fun with it while I find a route for the engine. |
ClayPerrine |
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#28
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Life's been good to me so far..... ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Admin Posts: 15,789 Joined: 11-September 03 From: Hurst, TX. Member No.: 1,143 Region Association: NineFourteenerVille ![]() ![]() |
You definitely need to have a hand throttle with MFI. It is mandatory for the warmup process.
If you are really planning on running MFI on a 914, then you need to find a copy of "Check, Measure and Adjust". It is the factory manual for setting up and tuning the MFI injection. Read it. Read it again, slowly. And read it again. Then follow it slowly, like your life depended on it. Do not deviate from the printed procedures even one iota. MFI is an analog computer. It is unforgiving and uncaring. You will probably need to replace every single rod end socket on the MFI system. They wear out and if they are bad, the car will run bad. And good luck finding a set of MFI protractors. They are required to set it up correctly. When you first get it running, it will not run well. But with time, and lots of patience, you can make it scream. And the sound of MFI at full throttle is a dream to a Porsche lover. It sounds a lot like a 917. (IMG:style_emoticons/default/biggrin.gif) |
B3owulf |
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#29
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Newbie ![]() Group: Members Posts: 45 Joined: 4-September 21 From: Clarksville TN Member No.: 25,879 Region Association: MidAtlantic Region ![]() ![]() |
Quick update, I made some progress on the four cylinder and got the 6 conversion parts boxed up for the moment.
I had a set of weber carbs that were quite nasty but cleaned up well, I rebuilt them with some old stock weber rebuild kits I found. I installed a new distributor, carbs, and cleaned up tin on the 1.7. Just waiting on a couple small parts and I will join it to the trans and get started with wiring and fuel (if I can get my work schedule to cooperate). I found two stripped out studs when installing the manifolds. Looks like the engine's previous owner tried the JB weld repair. It did not work. I installed some heli-coils and we are back on track. I listed the 2.4 for sale locally at the "wouldn't it be nice" price. If it sells it sells but I'm also putting some money aside for a rebuild. If all goes well I will have a drivable car by the end of the year and then can focus on rebuilding the 2.4. (IMG:http://www.914world.com/bbs2/uploads_offsite/i.ibb.co-25879-1721049068.1.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i.ibb.co-25879-1721049069.2.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i.ibb.co-25879-1721049069.3.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i.ibb.co-25879-1721049070.4.jpg) |
mb911 |
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#30
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 7,147 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest ![]() ![]() |
Why not sell off all the MFI parts and go carbs and keep it simple? I would not expect good leak down numbers on an engine that has been sitting a long time. You could build a cheap run stand and fire the engine up and check everything after it’s been properly warmed up. Again my suggestion would be carbs . You could sell the MFI setup complete and net enough money to pay for carbs.
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ClayPerrine |
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#31
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Life's been good to me so far..... ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Admin Posts: 15,789 Joined: 11-September 03 From: Hurst, TX. Member No.: 1,143 Region Association: NineFourteenerVille ![]() ![]() |
I was not trying to discourage you with what I said about MFI. I absolutely love it on a 914. It runs and drives wonderfully. I had MFI on a 2.4 in my six conversion for years. I actually thought about putting it on the 4.0 engine when I built it. But EFI wins out for the amount of driving I do in my 914.
If you want something easier to use, get Webers. They will bolt on, and you can sell the MFI parts to the 911 guys for big money. Or if you decide to keep the MFI, I have an electronic copy of check, measure and adjust for you. You could just fire up your daily driver and come to Okteenerfest. We are going to be there, and I would be happy to sit and talk with you about your fuel system. |
mb911 |
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#32
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 7,147 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest ![]() ![]() |
I was not trying to discourage you with what I said about MFI. I absolutely love it on a 914. It runs and drives wonderfully. I had MFI on a 2.4 in my six conversion for years. I actually thought about putting it on the 4.0 engine when I built it. But EFI wins out for the amount of driving I do in my 914. If you want something easier to use, get Webers. They will bolt on, and you can sell the MFI parts to the 911 guys for big money. Or if you decide to keep the MFI, I have an electronic copy of check, measure and adjust for you. You could just fire up your daily driver and come to Okteenerfest. We are going to be there, and I would be happy to sit and talk with you about your fuel system. (IMG:style_emoticons/default/agree.gif) |
B3owulf |
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#33
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Newbie ![]() Group: Members Posts: 45 Joined: 4-September 21 From: Clarksville TN Member No.: 25,879 Region Association: MidAtlantic Region ![]() ![]() |
I appreciate all the feedback, I will definitely try to make it out for Okteenerfest.
I have read check/measure/adjust and it made sense to me. The reason I am going with the 4 at the moment is simplicity. I just want to get the car driving and the 1.7 is the simplest path there. Once the car is on the road I can see about getting the six running on a stand before I swap it in. I dont want to go forward with welding in an engine mount and cutting holes for the oil tank before confirming the engine is good. I definitely have not given up on the six, I just want to keep moving forward on the project and get it running. |
mb911 |
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#34
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 7,147 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest ![]() ![]() |
I appreciate all the feedback, I will definitely try to make it out for Okteenerfest. I have read check/measure/adjust and it made sense to me. The reason I am going with the 4 at the moment is simplicity. I just want to get the car driving and the 1.7 is the simplest path there. Once the car is on the road I can see about getting the six running on a stand before I swap it in. I dont want to go forward with welding in an engine mount and cutting holes for the oil tank before confirming the engine is good. I definitely have not given up on the six, I just want to keep moving forward on the project and get it running. Makes sense to me. I know you’re a pretty technical guy from your background so I have confidence in your understanding of the MFI. As you get closer I can share my experience using carbs as throttle bodies and buying conversion bungs to use modern fuel injectors instead of MFI injectors and using Megasquirt. Really happy with the results and with your background a piece of cake. |
930cabman |
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#35
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 3,481 Joined: 12-November 20 From: Buffalo Member No.: 24,877 Region Association: North East States ![]() ![]() |
Why not sell off all the MFI parts and go carbs and keep it simple? I would not expect good leak down numbers on an engine that has been sitting a long time. You could build a cheap run stand and fire the engine up and check everything after it’s been properly warmed up. Again my suggestion would be carbs . You could sell the MFI setup complete and net enough money to pay for carbs. (IMG:style_emoticons/default/agree.gif) For me carbs are the EZ button for sure. There are Webers around for a reasonable and they are just plain cool |
mb911 |
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#36
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 7,147 Joined: 2-January 09 From: Burlington wi Member No.: 9,892 Region Association: Upper MidWest ![]() ![]() |
I might be willing to do some sort of trading my carb set up for your MFI setup as I just use them as throttle bodies
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JmuRiz |
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#37
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 5,485 Joined: 30-December 02 From: NoVA Member No.: 50 Region Association: MidAtlantic Region ![]() ![]() |
I might know an MFI expert, last I saw he had lots of parts on his shelf…let me know the mm you need and I’ll ask. I brainstormed doing the same thing when I get my car put together in a year or 5, or another 10…
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B3owulf |
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#38
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Newbie ![]() Group: Members Posts: 45 Joined: 4-September 21 From: Clarksville TN Member No.: 25,879 Region Association: MidAtlantic Region ![]() ![]() |
I might be willing to do some sort of trading my carb set up for your MFI setup as I just use them as throttle bodies I appreciate the offer but I do want to try getting the MFI working. It all looks to be intact and functional. Hopefully I can get enough time away from work to get the car on the road and get started on the six. |
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