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#1
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CREATIVE TYPE lV ENGINEERING ![]() ![]() ![]() Group: Retired Members Posts: 787 Joined: 20-June 04 From: Aliso Viejo, ca Member No.: 2,231 Region Association: None ![]() |
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Type 4 Unleashed |
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#2
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CREATIVE TYPE lV ENGINEERING ![]() ![]() ![]() Group: Retired Members Posts: 787 Joined: 20-June 04 From: Aliso Viejo, ca Member No.: 2,231 Region Association: None ![]() |
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johannes |
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#3
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Club Porsche 914 France member since 2005 ![]() ![]() ![]() ![]() Group: Members Posts: 3,092 Joined: 13-January 06 From: France Member No.: 5,409 Region Association: France ![]() |
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Type 4 Unleashed |
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#4
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CREATIVE TYPE lV ENGINEERING ![]() ![]() ![]() Group: Retired Members Posts: 787 Joined: 20-June 04 From: Aliso Viejo, ca Member No.: 2,231 Region Association: None ![]() |
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type2man |
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#5
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Member ![]() ![]() Group: Members Posts: 355 Joined: 3-March 09 From: Miami, Fl Member No.: 10,127 Region Association: South East States ![]() |
(IMG:style_emoticons/default/popcorn[1].gif) (IMG:style_emoticons/default/popcorn[1].gif) Keep it comin along, were all reading!!
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r_towle |
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#6
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Custom Member ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 24,705 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States ![]() ![]() |
Why are the rod bolts welded?
Why are there little pin holes in the top of the pistons? Rich |
Type 4 Unleashed |
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#7
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CREATIVE TYPE lV ENGINEERING ![]() ![]() ![]() Group: Retired Members Posts: 787 Joined: 20-June 04 From: Aliso Viejo, ca Member No.: 2,231 Region Association: None ![]() |
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Borderline |
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#8
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Senior Member ![]() ![]() ![]() Group: Members Posts: 720 Joined: 8-February 05 From: San Juan Bautista, CA Member No.: 3,577 Region Association: Northern California ![]() |
A 2.6 Ltr will make one hell of a street engine! Those look like steel cylinders. Have you done this sort of thing before? I've heard so many bad things about large steel cylinders. I've been thinking of doing something similar although a little smaller. What heads are you using? Are you doing anything special to help the heads seal better?
Keep us informed!! Thanks for posting. |
HAM Inc |
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#9
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Senior Member ![]() ![]() ![]() Group: Members Posts: 850 Joined: 24-July 06 From: Watkinsville,GA Member No.: 6,499 Region Association: None ![]() |
QUOTE It has been said that these cams are ground retarded because of the very close lobe center, -4* -6* or maybe more. I tried to find out exactly how much, but never did. And yes I emailed Schleicher, they sent me the cam spec's but could not tell me how much it was ground retarded. Why not just degree it and find out for yourself? It's not uncommon for actual cam specs' to not jibe with the card. Sometimes they get mislabled or misboxed, or even ground wrong. Degreeing is a good way to ensure you got what you wanted, or find out what you have. |
Type 4 Unleashed |
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#10
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CREATIVE TYPE lV ENGINEERING ![]() ![]() ![]() Group: Retired Members Posts: 787 Joined: 20-June 04 From: Aliso Viejo, ca Member No.: 2,231 Region Association: None ![]() |
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Chris Hamilton |
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#11
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Senior Member ![]() ![]() ![]() Group: Members Posts: 611 Joined: 7-March 06 From: Berkeley, CA Member No.: 5,687 ![]() |
I don't quite understand going with the stock weight flywheel. I'm using a 10lbs flywheel with an aluminum pressure plate and solid disc and I don't have any trouble with it being "too light", far from it! It just makes the thing easier to shift for me, and stop-and-go traffic on the bayshore doesn't bother me in that car.
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Type 4 Unleashed |
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#12
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CREATIVE TYPE lV ENGINEERING ![]() ![]() ![]() Group: Retired Members Posts: 787 Joined: 20-June 04 From: Aliso Viejo, ca Member No.: 2,231 Region Association: None ![]() |
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Chris Hamilton |
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#13
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Senior Member ![]() ![]() ![]() Group: Members Posts: 611 Joined: 7-March 06 From: Berkeley, CA Member No.: 5,687 ![]() |
I autocross my car and drive it on the freeway. Didn't notice much difference in mileage when I got the light pressure plate. I can get at least 14mpg if I drive the speed limit. How much difference have you noticed in mileage?
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jmill |
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#14
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Green Hornet ![]() ![]() ![]() ![]() Group: Members Posts: 2,449 Joined: 9-May 08 From: Racine, Wisconsin Member No.: 9,038 Region Association: Upper MidWest ![]() |
I would think you'd get worse mileage with a heavy flywheel. I thought they were beefy to handle the heat. (IMG:style_emoticons/default/confused24.gif)
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ArtechnikA |
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#15
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rich herzog ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 7,390 Joined: 4-April 03 From: Salted Roads, PA Member No.: 513 Region Association: None ![]() |
I would think you'd get worse mileage with a heavy flywheel. I thought they were beefy to handle the heat. Mostly they're heavy to improve idle and keep idiots who can't handle a clutch from stalling at stoplights. Consider this - when the car is in motion, THE ENTIRE CAR is attached to the rotating mass... There was a guy from Hawaii trying to promote the 'heavy flywheel makes for better mileage' theory about 20 years ago. You can tell how god an idea it is by observing all the 100-lb flywheels on Hondas and such... |
ChrisFoley |
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#16
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I am Tangerine Racing ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 7,990 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None ![]() ![]() |
(IMG:style_emoticons/default/agree.gif)
By itself the weight of the flywheel has nothing to do with fuel mileage, except that if a person has difficulty operating an engine with a lightened flywheel they may experience reduced mpgs. |
Todd Enlund |
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#17
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Resident Photoshop Guru ![]() ![]() ![]() ![]() Group: Members Posts: 3,251 Joined: 24-August 07 From: Laurelhurst (Portland), Oregon Member No.: 8,032 Region Association: Pacific Northwest ![]() |
There was a guy from Hawaii trying to promote the 'heavy flywheel makes for better mileage' theory about 20 years ago. You can tell how god an idea it is by observing all the 100-lb flywheels on Hondas and such... Well, there is a tradeoff... acceleration. And a point of diminishing return... which I'm sure is well short of 100lbs. A heavier flywheel will keep the engine speed more constant, which will result in better fuel economy. How much better? I dunno. Probably still depends more on the driver. I know of a guy that put a huge flywheel under his Pinto. He'd spool it up, shut the engine off, and drive home on the flywheel. Regenerative braking put energy back into the flywheel. |
Type 4 Unleashed |
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#18
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CREATIVE TYPE lV ENGINEERING ![]() ![]() ![]() Group: Retired Members Posts: 787 Joined: 20-June 04 From: Aliso Viejo, ca Member No.: 2,231 Region Association: None ![]() |
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Jake Raby |
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#19
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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 ![]() |
Light flywheels impact MPG because they require more constant throttle trim and that works the accelerator pump action more than anything..
I choose the flywheel based o the application.. I left the flywheel stock weight for my 2.4 going in the double cab, because it has a 915 trans and is heavy.. The larger the engine, the less notable the light flywheel actually is.. and remember, the stock 901 steel shoes pressure plate weighs 9 pounds by its self. |
Katmanken |
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#20
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You haven't seen me if anybody asks... ![]() ![]() ![]() ![]() Group: Members Posts: 4,738 Joined: 14-June 03 From: USA Member No.: 819 Region Association: Upper MidWest ![]() |
The heavier flywheel means higher system inertial which reduces shocks to the motor and tends to balance and smooth things out. When you have a heavier flywheel, you increase the resistance to changes in the motor's rotational rate. This can be a good thing if you want to increase the durability of your motor and keep rapid changes in rotational momentum (aka shock and Jerk) from trying to stop the motor. The shock and "jerk" loads apply instantaneous high pressure spikes to the motor components and the pressure fed bearings, and these loads can cause the oil film in the pressure fed bearings to be thinned dramatically or squeezed out.
Hmmm.... that may help explain why there are no 30 year old Honduh engines left- low mass flywheels, marginally sized bearing and wear surfaces resulting in high wear and high shock loads to the system... (IMG:style_emoticons/default/idea.gif) Sorry Jake, it's the engineer nerd in me.... |
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