1.7 Rebuild First Start Up Advice, 1.7 Start Up on stand |
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1.7 Rebuild First Start Up Advice, 1.7 Start Up on stand |
Robroe |
Jul 4 2024, 05:15 PM
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#1
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Member Group: Members Posts: 76 Joined: 10-August 21 From: Wenatchee, WA Member No.: 25,793 Region Association: Pacific Northwest |
Have 73 1.7 bought in pieces. Engine has been rebuilt and ‘souped up’ however I don’t know what internals were installed. New crank, cam, pistons, rods and heads. but I don’t know which ones. Weber 44 idf carbs. Never had oil in it and been stored unstarted for 10 yrs in climate control. I’ve added oil by slow dripping 2 quarts through the oil pressure sensor hole. Oil dripped out of the rockers so I’m pretty sure it got some oil as pre lube. It’s on a home built test stand with the transmission mounted with the starter.
I’m trying to turn the engine over by hand with the plugs out. Have squirted oil in each plug hole. I’m able to turn the engine by hand about 45 degrees and it gets harder to spin so can’t go any further. Would it be a good idea to pull the rocker arms to see if the builder installed some wild cam without checking valve/piston clearance? It doesn’t feel like internals are hitting each other but who knows? Would hate to pull the heads if I don’t have to. Any thoughts before I break something? Rob Roe Newbie |
Montreal914 |
Jul 4 2024, 05:23 PM
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#2
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Senior Member Group: Members Posts: 1,684 Joined: 8-August 10 From: Claremont, CA Member No.: 12,023 Region Association: Southern California |
Cheap Amazon emdoscope connected to you phone should allow you to see what is happening in the chaber via the spark plug hole I would think. Mine has a 45 degree mirror attachment to view on the side.
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Superhawk996 |
Jul 4 2024, 05:27 PM
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#3
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914 Guru Group: Members Posts: 6,512 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
With what you just described, I can’t see any scenario where I wouldn’t be taking it apart.
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emerygt350 |
Jul 4 2024, 06:00 PM
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#4
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Advanced Member Group: Members Posts: 2,476 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
When you say 'by hand', what do you mean? A breaker bar or pulling on the fan?
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930cabman |
Jul 4 2024, 08:18 PM
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#5
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Advanced Member Group: Members Posts: 3,651 Joined: 12-November 20 From: Buffalo Member No.: 24,877 Region Association: North East States |
Have 73 1.7 bought in pieces. Engine has been rebuilt and ‘souped up’ however I don’t know what internals were installed. New crank, cam, pistons, rods and heads. but I don’t know which ones. Weber 44 idf carbs. Never had oil in it and been stored unstarted for 10 yrs in climate control. I’ve added oil by slow dripping 2 quarts through the oil pressure sensor hole. Oil dripped out of the rockers so I’m pretty sure it got some oil as pre lube. It’s on a home built test stand with the transmission mounted with the starter. I’m trying to turn the engine over by hand with the plugs out. Have squirted oil in each plug hole. I’m able to turn the engine by hand about 45 degrees and it gets harder to spin so can’t go any further. Would it be a good idea to pull the rocker arms to see if the builder installed some wild cam without checking valve/piston clearance? It doesn’t feel like internals are hitting each other but who knows? Would hate to pull the heads if I don’t have to. Any thoughts before I break something? Rob Roe Newbie (IMG:style_emoticons/default/welcome.png) If you are unable to get a full rotation of the crank somewhat easily, start dis assembling her. Or try the starter to spin it over. If you are able to get her to spin, connect an oil pressure gauge and see if she will pump up some oil pressure. Might get lucky (IMG:style_emoticons/default/sawzall-smiley.gif) |
bkrantz |
Jul 4 2024, 08:29 PM
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#6
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914 Guru Group: Members Posts: 8,114 Joined: 3-August 19 From: SW Colorado Member No.: 23,343 Region Association: Rocky Mountains |
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Superhawk996 |
Jul 4 2024, 09:38 PM
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#7
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914 Guru Group: Members Posts: 6,512 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
. . . Or try the starter to spin it over. If you are able to get her to spin, connect an oil pressure gauge and see if she will pump up some oil pressure. Might get lucky (IMG:style_emoticons/default/sawzall-smiley.gif) I would strongly advise against this. You will not get lucky. The starter exerts a lot of torque on the crankshaft. The starter is fully capable of bending valves. I don’t know the gear ratio between starter and ring gear off the top of my head but it’s probably about a 10:1 mechanical advantage. If you already have an interference that isn’t allowing you to rotate the crank - more mechanical advantage will only serve to break or bend things. Without spark plugs the crank should rotate freely by hand, no exceptions. Oil pressure has nothing to do with not being able to freely rotate the crank at this stage in the game. If the original builder didn’t apply assembly lube to the main bearings and the cam lobes, the damage would be done before the engine ever builds oil pressure by rotating it. And if that sort of negligence was causing a lack of hand rotation (I’ll guarantee it isn’t), that would be all the more reason to tear it down, find out what was done, and reassemble it correctly. |
Superhawk996 |
Jul 4 2024, 09:52 PM
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#8
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914 Guru Group: Members Posts: 6,512 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
If you are unable to get a full rotation of the crank somewhat easily, start dis assembling her. (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/welcome.png) |
Superhawk996 |
Jul 4 2024, 09:55 PM
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#9
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914 Guru Group: Members Posts: 6,512 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
Without spark plugs the crank should rotate freely by hand, no exceptions. [edit] - I guess the exception would be if the transmission is in gear. Make sure the trans is in neutral and that you’re not trying to rotate the whole gear cluster and differential as you’re rotating the engine by hand |
emerygt350 |
Jul 5 2024, 05:01 AM
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#10
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Advanced Member Group: Members Posts: 2,476 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
You could remove the rockers and give it a go, if it turns freely you know that either your hitting or you have some crazy powerful springs ...
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Robroe |
Jul 6 2024, 12:02 AM
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#11
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Member Group: Members Posts: 76 Joined: 10-August 21 From: Wenatchee, WA Member No.: 25,793 Region Association: Pacific Northwest |
You could remove the rockers and give it a go, if it turns freely you know that either your hitting or you have some crazy powerful springs ... Removed the rockers and push rods. Could turn the engine by hand by gripping the fan. I’m considering cranking the starter with the rockers and push rods removed to see if it builds enough oil pressure to turn off the oil warning light. If I get that far, then was considering reinstalling the push rods and rockers and adjust the valve clearance very loose and try to turn it over again by hand. With luck, there will be no valve/piston interference and I can turn the crank by hand. Not sure what valve springs I have. They are doubles but that’s all I know. I assume the springs can be heavy enough to make it harder to turn by hand. But sounds like it should be turntable by hand unless there is clearance issue. Going very slow and cautious. Thanks for your thoughts. Please keep your suggestions coming! I might just get an endoscope camera to look inside. I can see numbers on the pistons through the spark plug holes but can’t read the numbers. |
emerygt350 |
Jul 6 2024, 05:10 AM
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#12
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Advanced Member Group: Members Posts: 2,476 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
I wouldn't worry about oil pressure yet but it couldn't hurt with the rockers off.
The springs are a little worrisome to me. I know they are used but I wonder if that means there is some radical cam in there. Do you have a micrometer? Measuring the lift on the cam might be interesting. You should be able to ballpark it with the pushrod travel. To determine if it's the valve springs you could put them back on one intake valve and try turning it by hand. If that works add another and keep going. If it gets progressively more difficult but the engine keeps turning... |
emerygt350 |
Jul 6 2024, 06:15 AM
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#13
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Advanced Member Group: Members Posts: 2,476 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
And it just occurred to me... Check top dead center on 1 and verify the correct timing of the valve events. If they did just 'throw it back together' the cam might be off. I doubt that's the case, but it would be good to know.
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technicalninja |
Jul 6 2024, 07:15 AM
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#14
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Senior Member Group: Members Posts: 1,961 Joined: 31-January 23 From: Granbury Texas Member No.: 27,135 Region Association: Southwest Region |
With what you just described, I can’t see any scenario where I wouldn’t be taking it apart. (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) It's already OUT! With the plugs and the rockers off it should spin completely free. You should be able to turn the flywheel/front pully with a single finger and no effort. "Gripping" should not be required. You should tear down. IMO doing anything else is a waste of time. you should be able to get that down to a "short block" with the rods hanging out of the case fairly quickly. The most likely culprit IMO is a ring that got damaged during installation. Using a friend supporting the rods that should "free wheel" with zero drag. During the tear down you should verify both bore and stroke. The 44s it came with should be on a BIG motor, not a small one. |
Robroe |
Jul 7 2024, 12:19 AM
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#15
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Member Group: Members Posts: 76 Joined: 10-August 21 From: Wenatchee, WA Member No.: 25,793 Region Association: Pacific Northwest |
With what you just described, I can’t see any scenario where I wouldn’t be taking it apart. (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) It's already OUT! With the plugs and the rockers off it should spin completely free. You should be able to turn the flywheel/front pully with a single finger and no effort. "Gripping" should not be required. You should tear down. IMO doing anything else is a waste of time. you should be able to get that down to a "short block" with the rods hanging out of the case fairly quickly. The most likely culprit IMO is a ring that got damaged during installation. Using a friend supporting the rods that should "free wheel" with zero drag. During the tear down you should verify both bore and stroke. The 44s it came with should be on a BIG motor, not a small one. Ordered borescope today to look inside cylinders through spark plug holes. Hope to learn more about which pistons were installed (part numbers from tops) and better idea of valves and heads. From there I hope to decide whether to pull the heads for a better look. I”ll probably try to measure piston travel and valve lift too. Would be nice to know a bit more about what I’ve got before trying to start. The fan is very close to the case. Seems like it might be touching a little as I spin the motor by hand. It’s so pretty with the tin and case powder coated. Hope I don’t have to tear it down too far if at all. Will post what I find with the scope. Might even figure out how to take pictures. |
930cabman |
Jul 7 2024, 08:20 AM
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#16
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Advanced Member Group: Members Posts: 3,651 Joined: 12-November 20 From: Buffalo Member No.: 24,877 Region Association: North East States |
With what you just described, I can’t see any scenario where I wouldn’t be taking it apart. (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) It's already OUT! With the plugs and the rockers off it should spin completely free. You should be able to turn the flywheel/front pully with a single finger and no effort. "Gripping" should not be required. You should tear down. IMO doing anything else is a waste of time. you should be able to get that down to a "short block" with the rods hanging out of the case fairly quickly. The most likely culprit IMO is a ring that got damaged during installation. Using a friend supporting the rods that should "free wheel" with zero drag. During the tear down you should verify both bore and stroke. The 44s it came with should be on a BIG motor, not a small one. Ordered borescope today to look inside cylinders through spark plug holes. Hope to learn more about which pistons were installed (part numbers from tops) and better idea of valves and heads. From there I hope to decide whether to pull the heads for a better look. I”ll probably try to measure piston travel and valve lift too. Would be nice to know a bit more about what I’ve got before trying to start. The fan is very close to the case. Seems like it might be touching a little as I spin the motor by hand. It’s so pretty with the tin and case powder coated. Hope I don’t have to tear it down too far if at all. Will post what I find with the scope. Might even figure out how to take pictures. Are you able to get her to spin reasonably easy? if so, you might be on your way. Fan will be close to the housing, perhaps a special washer was not installed. |
Robroe |
Jul 7 2024, 03:47 PM
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#17
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Member Group: Members Posts: 76 Joined: 10-August 21 From: Wenatchee, WA Member No.: 25,793 Region Association: Pacific Northwest |
With what you just described, I can’t see any scenario where I wouldn’t be taking it apart. (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) It's already OUT! With the plugs and the rockers off it should spin completely free. You should be able to turn the flywheel/front pully with a single finger and no effort. "Gripping" should not be required. You should tear down. IMO doing anything else is a waste of time. you should be able to get that down to a "short block" with the rods hanging out of the case fairly quickly. The most likely culprit IMO is a ring that got damaged during installation. Using a friend supporting the rods that should "free wheel" with zero drag. During the tear down you should verify both bore and stroke. The 44s it came with should be on a BIG motor, not a small one. Ordered borescope today to look inside cylinders through spark plug holes. Hope to learn more about which pistons were installed (part numbers from tops) and better idea of valves and heads. From there I hope to decide whether to pull the heads for a better look. I”ll probably try to measure piston travel and valve lift too. Would be nice to know a bit more about what I’ve got before trying to start. The fan is very close to the case. Seems like it might be touching a little as I spin the motor by hand. It’s so pretty with the tin and case powder coated. Hope I don’t have to tear it down too far if at all. Will post what I find with the scope. Might even figure out how to take pictures. Are you able to get her to spin reasonably easy? if so, you might be on your way. Fan will be close to the housing, perhaps a special washer was not installed. Yes it spins fairly easy by pushing the fan by hand. Just remembered Jake Raby advice on loosening the oil filter when cranking the engine to purge air out of the oil passages so oil pressure can be established. Might give that a try while waiting for the boroscope to arrive. If valve/piston clearance looks ok with boroscope I will likely put the push rods and rockers back on. And check with boroscope with valves opening. Then loosen tappets to reset valve clearance and measure cam lobe height by measuring push rod travel from valve closed to valve open. Will also measure piston travel to learn what crank I have. And check compression. Anything questionable and I’ll tear it down to inspect. The motor was built over 10 yrs ago by a supposed “race engine guy” but no records. It looks nice and turns over well by hand and with starter without the rockers installed. |
930cabman |
Jul 7 2024, 03:54 PM
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#18
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Advanced Member Group: Members Posts: 3,651 Joined: 12-November 20 From: Buffalo Member No.: 24,877 Region Association: North East States |
With what you just described, I can’t see any scenario where I wouldn’t be taking it apart. (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) It's already OUT! With the plugs and the rockers off it should spin completely free. You should be able to turn the flywheel/front pully with a single finger and no effort. "Gripping" should not be required. You should tear down. IMO doing anything else is a waste of time. you should be able to get that down to a "short block" with the rods hanging out of the case fairly quickly. The most likely culprit IMO is a ring that got damaged during installation. Using a friend supporting the rods that should "free wheel" with zero drag. During the tear down you should verify both bore and stroke. The 44s it came with should be on a BIG motor, not a small one. Ordered borescope today to look inside cylinders through spark plug holes. Hope to learn more about which pistons were installed (part numbers from tops) and better idea of valves and heads. From there I hope to decide whether to pull the heads for a better look. I”ll probably try to measure piston travel and valve lift too. Would be nice to know a bit more about what I’ve got before trying to start. The fan is very close to the case. Seems like it might be touching a little as I spin the motor by hand. It’s so pretty with the tin and case powder coated. Hope I don’t have to tear it down too far if at all. Will post what I find with the scope. Might even figure out how to take pictures. Are you able to get her to spin reasonably easy? if so, you might be on your way. Fan will be close to the housing, perhaps a special washer was not installed. Yes it spins fairly easy by pushing the fan by hand. Just remembered Jake Raby advice on loosening the oil filter when cranking the engine to purge air out of the oil passages so oil pressure can be established. Might give that a try while waiting for the boroscope to arrive. If valve/piston clearance looks ok with boroscope I will likely put the push rods and rockers back on. And check with boroscope with valves opening. Then loosen tappets to reset valve clearance and measure cam lobe height by measuring push rod travel from valve closed to valve open. Will also measure piston travel to learn what crank I have. And check compression. Anything questionable and I’ll tear it down to inspect. The motor was built over 10 yrs ago by a supposed “race engine guy” but no records. It looks nice and turns over well by hand and with starter without the rockers installed. All good news, you may have a winner. Always good to check things out, but it's possible to assemble the beast and she will run. FI or carbs? |
Robroe |
Jul 7 2024, 05:20 PM
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#19
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Member Group: Members Posts: 76 Joined: 10-August 21 From: Wenatchee, WA Member No.: 25,793 Region Association: Pacific Northwest |
With what you just described, I can’t see any scenario where I wouldn’t be taking it apart. (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/agree.gif) It's already OUT! With the plugs and the rockers off it should spin completely free. You should be able to turn the flywheel/front pully with a single finger and no effort. "Gripping" should not be required. You should tear down. IMO doing anything else is a waste of time. you should be able to get that down to a "short block" with the rods hanging out of the case fairly quickly. The most likely culprit IMO is a ring that got damaged during installation. Using a friend supporting the rods that should "free wheel" with zero drag. During the tear down you should verify both bore and stroke. The 44s it came with should be on a BIG motor, not a small one. Ordered borescope today to look inside cylinders through spark plug holes. Hope to learn more about which pistons were installed (part numbers from tops) and better idea of valves and heads. From there I hope to decide whether to pull the heads for a better look. I”ll probably try to measure piston travel and valve lift too. Would be nice to know a bit more about what I’ve got before trying to start. The fan is very close to the case. Seems like it might be touching a little as I spin the motor by hand. It’s so pretty with the tin and case powder coated. Hope I don’t have to tear it down too far if at all. Will post what I find with the scope. Might even figure out how to take pictures. Are you able to get her to spin reasonably easy? if so, you might be on your way. Fan will be close to the housing, perhaps a special washer was not installed. Yes it spins fairly easy by pushing the fan by hand. Just remembered Jake Raby advice on loosening the oil filter when cranking the engine to purge air out of the oil passages so oil pressure can be established. Might give that a try while waiting for the boroscope to arrive. If valve/piston clearance looks ok with boroscope I will likely put the push rods and rockers back on. And check with boroscope with valves opening. Then loosen tappets to reset valve clearance and measure cam lobe height by measuring push rod travel from valve closed to valve open. Will also measure piston travel to learn what crank I have. And check compression. Anything questionable and I’ll tear it down to inspect. The motor was built over 10 yrs ago by a supposed “race engine guy” but no records. It looks nice and turns over well by hand and with starter without the rockers installed. All good news, you may have a winner. Always good to check things out, but it's possible to assemble the beast and she will run. FI or carbs? Weber 44s. I have all the FI stuff from 73 and a complete 74 1.8 parts car. Will see if the webers are fun and tunable. |
emerygt350 |
Jul 7 2024, 05:26 PM
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#20
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Advanced Member Group: Members Posts: 2,476 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
Hopefully it was just crazy compression and stiff springs....
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