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> Engine rebuild: wich camshaft ?, 2.0 rebuild 125-130 hp expected
pat4
post Nov 14 2003, 08:03 AM
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Philippe
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Hello,

I decided to rebuild my 2.0 engine. FI have been removed in a previous life, and the car is running (baddly) with two Weber 44 IDF. So we decided to rebuild all. As the cranckase will be open, it seems the right time to choose a new camshaft. But wich one ? Wich duration ? Wich lifting ?

I do not want to build a race engine, but a funny street car. 120 to 130 Hp are expected, with also a little job on heads (Comp. ratio upgraded from 8.0 to 8.5)

Any advice welcome.
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rhodyguy
post Nov 14 2003, 08:17 AM
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Chimp Sanctuary NW. Check it out.
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read the recent thread regarding opening up your cylinders and installing the keith black pistons, displacement would be 2056cc. general thought is your 44's are a bit large for a 2.0. is the 140hp range a bit ambitious for a "mild" engine?

kevin
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pat4
post Nov 14 2003, 08:39 AM
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Kevin,

these threads does not speak about camshafts but pistons and cyliders. No, the question can resume in this :

Webcam 270° (#86), Webcam 290° (#86a) or Schleicher 296° ?

About pistons, my mechanic told me that it could be very intersting to install 94mm VW type1 pistons that are forged and very light. He said it will give more acceleration. Logical... He also said that if cylinders need to be re-bored to 96mm keith black pistons will be the best choice but he also think that cylinder basis will become in weakening (? good word ?)
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seanery
post Nov 14 2003, 09:15 AM
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waiting to rebuild whitey!
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Cam thread

This thread has a bit of info from when I was looking for a cam. I'm very pleased with my cam!
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brant
post Nov 14 2003, 09:19 AM
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just my 2 cents...
a mild 2.0 race engine puts out about 140 with 9.5 compression, big valves, and alot of head work.

brant
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machina
post Nov 14 2003, 09:43 AM
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QUOTE(brant @ Nov 14 2003, 11:19 AM)
just my 2 cents...
a mild 2.0 race engine puts out about 140 with 9.5 compression, big valves, and alot of head work.

brant

can you run pump gas with a motor like that?

dr
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Jake Raby
post Nov 14 2003, 11:42 AM
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A camshaft cannot be a guesswork item!!

The main things that any experienced engine builder takes into account when selecting a cam are important.

Camshafts change the events that occur within the engine totally, and thus effect the engines "Dynamic compression ratio" This happens due to performance cams opening the valves at different crankshaft positions, and normally bleeding more compression from the cylinder, thus dropping the CR while the engine is running.

When I got heavy into these engines, the assembly was easy, the machining was easy, but the power was not there. The engines ran rich, were hard to tune and just ball-less. Thats before I became a configuration specialist!

Configuration is where it is ALL AT! Amisconfigured engine is a nightmare, idles rough, runs rich, runs hot, and makes no power at any RPM. The biggest problem I have to fix with other shops work is their combinations!

Many times the CR is not adequate for the cam, the valves are too large, and the bore is too big, or any combination of those.

The key is to have the cylinder heads designed and flowed BEFORE choosing the camshaft, and CR. I design my engines around my theory of running more static CR and bleeding it with a nice cam, which is most of the time set up with split duration.

I have 20 different custom camshafts made up by Web Cam. If you purchase a cam from me, I will take the time to set you up with what you need, based on experience.
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Bleyseng
post Nov 14 2003, 11:53 AM
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Take him up on his offer, dude. The right cam is where its at and money well spent.

Geoff
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Jake Raby
post Nov 14 2003, 11:54 AM
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In a TIV the cam is everything! Thatshow my 2316 makes more power than most 2600+ engines!
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bernbomb914
post Nov 14 2003, 12:02 PM
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Jake what increase in flow in the heads would you consider good over stock?

Bernie
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Jake Raby
post Nov 14 2003, 12:07 PM
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And thats all according to the application, altitude (air density the engine normally sees) and the powerband you want..

I hate not to give direct numbers, but if I do it would be misleading! There is no standard for performance, no 2 cars, or their drivers are the same.

Its ALL in the combo!
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bernbomb914
post Nov 14 2003, 12:16 PM
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I ask because my head man said he got a 86% increase in flow on my heads. which I find hard to beleve. his shop is about 5000 ft elevation. he increased the valve size and ported the heads. He has a very nice flow bench

Bernie
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Jake Raby
post Nov 14 2003, 12:22 PM
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Absolutely no way he got that on both sides!
He may have gotten 85% of the intake flow out the exhaust, but it just ain't happening for an 85% increase.
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bernbomb914
post Nov 14 2003, 12:46 PM
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Thanks I thought not. but I am happy for any improvement.
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brant
post Nov 14 2003, 04:28 PM
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[QUOTE]


sorry for the slow reply about the pump gas...
in short.. no... but it also depends upon your altitude.
brant
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pat4
post Nov 16 2003, 06:54 AM
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I totally agree with Jake Raby about the camshaft importance. It is the reason why I inquire with you, specialists (IMG:style_emoticons/default/wub.gif)

So, Jake, May be you can suggest me any configuration :

Option 1 : 2.0 GB totally stock except 2x44 IDF and new camshaft/lifters

Option 2 : The same, except using VW T1 94mm forged pistons that are 100gr. lighter than stock ones and that increase CR.

Thanks a lot for you interest.
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