Type IV rebuild / refresh thread. Nothing ground breaking., Changing cam in low mileage rebuit 1.8, making it a little hotter! Oh yea! |
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Type IV rebuild / refresh thread. Nothing ground breaking., Changing cam in low mileage rebuit 1.8, making it a little hotter! Oh yea! |
stugray |
Jun 30 2016, 01:53 PM
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#21
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Advanced Member Group: Members Posts: 3,825 Joined: 17-September 09 From: Longmont, CO Member No.: 10,819 Region Association: None |
I called LN Engineering, they found the specs for the cam I have sitting around... Lift: I .335 E .400 Duration: 290 I/E Duration @ .050: I 252 E 254 108 Lobe center. So those numbers seem a little odd. If that is lobe lift at the cam you will have approx. Ivalve = .460, Evalve = .520 at the valves Just as a datapoint, there are no webcams that are off much at all between Intake & exhaust advertised lift (although there is some). The 86b I run has advertise lift of .500/.500 at the valves with a similar duration as yours. The measured on mine for the 86b was I valve .475 Evalve .504 SO your cam is even a little more 'aggressive' than an 86b as far as intake/exhaust flow ratio is. Maybe that cam was destined for a big valve setup? |
G e o r g e |
Jun 30 2016, 04:50 PM
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#22
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Dr Group: Members Posts: 1,905 Joined: 20-September 05 From: Southern Cal Member No.: 4,832 Region Association: None |
a thread over on the samba Jake references a web cam 86a/86a +2 1/2 as the equal to the 9600.
looks like the 290 duration fit into their readings the + 2 1/2 must account for the intake and exhaust changes |
Mueller |
Jun 30 2016, 06:38 PM
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#23
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914 Freak! Group: Members Posts: 17,150 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None |
a thread over on the samba Jake references a web cam 86a/86a +2 1/2 as the equal to the 9600. looks like the 290 duration fit into their readings the + 2 1/2 must account for the intake and exhaust changes Thanks, of course I am drawing a blank what "2 1/2" means. Advanced? |
maf914 |
Jul 1 2016, 07:11 AM
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#24
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Not a Guru! Group: Members Posts: 3,049 Joined: 30-April 03 From: Central Florida Member No.: 632 Region Association: None |
It looks like the cam specs are for a split duration cam, with the lift and duration for the exhaust valve increased to overcome the more restrictive exhaust port flow (relative to the better flowing intake port). At least that is what I recall from earlier tech threads from 914 World and ShopTalkForums.
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Jake Raby |
Jul 1 2016, 07:50 AM
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#25
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Engine Surgeon Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
The 9600 is a straight pattern version of the 9610, which is the more modern offering. I stopped using the 9600 in 2007.
Still a great cam. Just build it! |
Mueller |
Jul 1 2016, 07:51 AM
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#26
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914 Freak! Group: Members Posts: 17,150 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None |
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Mark Henry |
Jul 1 2016, 07:53 AM
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#27
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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 |
Jake is it an FI cam?
Mike said he was thinking L-jet. |
stugray |
Jul 1 2016, 08:22 AM
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#28
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Advanced Member Group: Members Posts: 3,825 Joined: 17-September 09 From: Longmont, CO Member No.: 10,819 Region Association: None |
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Mueller |
Jul 1 2016, 10:11 AM
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#29
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914 Freak! Group: Members Posts: 17,150 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None |
Jake is it an FI cam? Mike said he was thinking L-jet. If worth it, I'll swap to Megasquit with a bigger TB or even ITBs I've already bought 911 swivel adjusters (new, factory items) Next will be the lifters and pushrods from LN....is the DVD for building Type IVs available anymore? |
Mark Henry |
Jul 1 2016, 11:45 AM
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#30
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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 |
....is the DVD for building Type IVs available anymore? Just post your progress, you'll get lots of help. (IMG:style_emoticons/default/shades.gif) |
r_towle |
Jul 1 2016, 01:08 PM
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#31
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Custom Member Group: Members Posts: 24,645 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
Yup, just build it.
Take your time, learn about how to do the valve geometry and you will enjoy the process. Rich |
Mueller |
Jul 1 2016, 06:18 PM
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#32
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914 Freak! Group: Members Posts: 17,150 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None |
Curious if I should be looking for a cheap single or dual carb setup for the break-in since with a new cam and lifters it'll be like starting a newly rebuilt engine.
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Mueller |
Jul 1 2016, 10:08 PM
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#33
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914 Freak! Group: Members Posts: 17,150 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None |
I ran the part numbers on the head and the cylinders, 1.8 parts.
Cylinders are in great shape, no pitting just some discoloration. Stock camshaft looks odd, or at least to me. The heads show no signs of cracks, I didn't have to do much to clean the springs and seat area, just wiped off the old oil and sprayed with hot water. Pistons are in good shape, the one pictured has signs of something falling in there or is that detonation? Combustion chamber has a few little divots just like the piston, very minor. I think piston #4 had the most buildup on the top. I still have a bunch more cleaning to do to the heads and case. |
Valy |
Jul 1 2016, 11:49 PM
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#34
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Senior Member Group: Members Posts: 1,677 Joined: 6-April 10 From: Sunnyvale, CA Member No.: 11,573 Region Association: Northern California |
That cam is a paperweight.
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Mueller |
Jul 5 2016, 11:11 AM
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#35
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914 Freak! Group: Members Posts: 17,150 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None |
Both heads will need a little machine work to clean up the head to cylinder mating surface, I removed the head gaskets the previous engine builder used. I will not be using gaskets here again.
(IMG:http://www.914world.com/bbs2/uploads/post-87-1467611405_thumb.jpg) (IMG:http://www.914world.com/bbs2/uploads/post-87-1467611518_thumb.jpg) |
r_towle |
Jul 5 2016, 11:47 AM
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#36
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Custom Member Group: Members Posts: 24,645 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
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JOEPROPER |
Jul 5 2016, 12:48 PM
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#37
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The answer is "no" unless you ask... Group: Members Posts: 1,191 Joined: 21-November 15 From: White Plains New York Member No.: 19,387 Region Association: North East States |
No head gaskets? Is that right? I didn't know that was an option... (IMG:style_emoticons/default/smoke.gif)
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Mueller |
Jul 9 2016, 07:10 PM
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#38
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914 Freak! Group: Members Posts: 17,150 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None |
Do I have to buy a new gear for the cam or can I remove the rivets on the original cam and the use bolts?
I saw a straight cut gear in the classifieds....too loud? What about cutting a groove in it? And if I do use my original cam gear worth making it adjustable able? |
Valy |
Jul 9 2016, 09:19 PM
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#39
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Senior Member Group: Members Posts: 1,677 Joined: 6-April 10 From: Sunnyvale, CA Member No.: 11,573 Region Association: Northern California |
Reuse.
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jcd914 |
Jul 9 2016, 11:34 PM
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#40
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Advanced Member Group: Members Posts: 2,081 Joined: 7-February 08 From: Sacramento, CA Member No.: 8,684 Region Association: Northern California |
Do I have to buy a new gear for the cam or can I remove the rivets on the original cam and the use bolts? I saw a straight cut gear in the classifieds....too loud? What about cutting a groove in it? And if I do use my original cam gear worth making it adjustable able? Send the cam over to Elgins and get it reground. |
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