Replacing L2 camshafts in S4 with strombergs

PostPost by: collins_dan » Tue Jan 22, 2013 2:19 am

They have a 350 lift and 304 duration, and I was thinking about replacing with sprint cams, which have a 360 lift and 270 duration. They would drop right in with no modifications required and be better for fast road use. Unfortunately, I am having trouble locating some, but it got me to thinking if they are the best option.

Dave Bean's 112 grind has a 385 lift and 300 duration. Sounds like a potentially even better option than the sprint cam, but not sure if they will drop right in. Has anyone installed them? Do they require additional modifications to fit?

I read a lot here about QED and John McCoy, but not sure if any of their cams are comparable or better than sprint cams, or if they are oriented towards more modified engines.

I appreciate any advice on other appropriate camshaft options, or thoughts on where to find sprint cams.

Thanks, Dan
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PostPost by: rgh0 » Tue Jan 22, 2013 3:36 am

Hi Dan

Ideally if cost is no option then a short duration - around 280 degrees seat to seat and high lift 0.41 or higher gives the best outcome for extra performance with good torque spread in a road car. Dave Bean, McCoy and QED and others make a cam like this. However it is not a drop in replacement as the lift is to great for the standard valve gear which is why cams such as the L2 and DB 112 with longer duration but standard lift were made as a cheap drop in top end power boost but at the expense of midrange torque.

The .385 lift for the DB cam is right at the limit of the standard valve springs capability ( some would say over the limit) and you would want to check your engines specific setup to ensure it could handle it OK as assembly tolerances and / or modifications over the years may have resulted in less than than this lift capability with the standard springs.

cheers
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PostPost by: StressCraxx » Tue Jan 22, 2013 3:53 am

http://www.elgincams.com/c-lot.html

Dema Elgin grinds cams for many of the engine builders on the west coast. He does excellent work. He does not sit at the computer much, he is at the bench, so call him rather than email.

Years ago, he had a machine shop in Redwood City, CA. He did all the machine work for my motor. The quality of work was outstanding. Dema sold the shop and moved to Santa Rosa to do what he likes best. He is a one man shop now.

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PostPost by: collins_dan » Tue Jan 22, 2013 2:28 pm

Thanks for your replies.

Rohan, If I wanted to go the drop-in route, would you recommend the sprint cams over the DB 112s for a fast road car? In reading the archives, it sounds like the duration of 300 is not necessarily a good trade-off for the additional lift. I do like what I read about the benefits of the 410 lift, while holding the duration in the 280 vicinity, but I am unclear about how extensive (and expensive) the changes would be. To read some of your the posts in the archives, which I think are more oriented towards the 450 lift, it sounds like a significant rebuild by an engine specialist. Is the same true if the lift is just 410? Also, the car runs on strombergs, is that problematic?

Dan, Thanks. I'll check with Dema.

All the best, Dan
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PostPost by: lotocone » Tue Jan 22, 2013 4:18 pm

StressCraxx wrote:http://www.elgincams.com/c-lot.html

Dema Elgin grinds cams for many of the engine builders on the west coast. He does excellent work. He does not sit at the computer much, he is at the bench, so call him rather than email.

Years ago, he had a machine shop in Redwood City, CA. He did all the machine work for my motor. The quality of work was outstanding. Dema sold the shop and moved to Santa Rosa to do what he likes best. He is a one man shop now.

Dan


Dan and Dan,

I think that calling Elgin is a very good idea. My engine had L2 cams in the 90s and I replaced them with Elgin 67-14 cams to improve the low end torque. I don't see that particular cam on his list now, but it looks like there are similar ones. I think I sent them a pair of stock cams that they ground to get the 67-14 spec. which has 0.372" lift. Not sure about the duration. Anyway, there are a lot of stop signs a traffic lights here and I appreciate having improved low end torque to get moving. The engine has 130 hp based on a dyno test. My car has Webers so I can't comment on Strombergs.

There is some good info about cams on Elgin's website http://www.elgincams.com/

Let us know how it goes.

Bob
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PostPost by: collins_dan » Tue Jan 22, 2013 4:58 pm

Thanks Bob. I just hung up with another forum member that has a standard set of cams that could be reground to the 67-14 grind or sprint spec. He also has a set of KH1 (351 lift, 280 duration) and a set of KH2 (375 lift, 280 duration), which seem like good options as well. All the best, Dan
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PostPost by: lotocone » Tue Jan 22, 2013 8:43 pm

collins_dan wrote:Thanks Bob. I just hung up with another forum member that has a standard set of cams that could be reground to the 67-14 grind or sprint spec. He also has a set of KH1 (351 lift, 280 duration) and a set of KH2 (375 lift, 280 duration), which seem like good options as well. All the best, Dan


Dan, I'm guessing that Elgin stopped making the 67-14 grind because he made an improved cam, or maybe more than one. I bet he would recommend something good for your engine and type of driving. The KH cams sound good, but I'm no expert. Maybe someone else can comment.

Bob
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PostPost by: collins_dan » Tue Jan 22, 2013 9:51 pm

Just hung up with Mr Elgin. Smart, busy man. He has a 389 lift, 272 duration that is very streetable. I need to source some standard cams for him to grind and figure out how to fill in all the info on his order form :shock:. He thought as long as the lift stays under 390, it should not require a lot of head work.
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PostPost by: Galwaylotus » Tue Jan 22, 2013 9:59 pm

"Re: Replacing L2 camshafts in S4 with strombergs"

I didn't know you could replace camshafts with carburetors! :shock: :lol: :lol:
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PostPost by: collins_dan » Tue Jan 22, 2013 10:21 pm

Very funny. I was trying to give as much info as might be needed to help.
Dan
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