Pelican Parts Forums - E cam value?

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What is a nice set of E cams worth?

They are coming out of my car on Thursday and will be for sale. I pulled the rockers this weekend and all of the lobes look perfect.

Paul

regrind E cams on Ebay 295.00 . Motor miser 299.00 Ex

What are you going to put in, paul?

What is going in the 3.5? Mo' Powah!

I am putting in a Webcam racing cam for big bore motors. The guy installing the cams has a dyno so i should have results in a week or so. It should be quite an improvement.

PLT

Quote:

Originally posted by Paul Thomas
I am putting in a Webcam racing cam for big bore motors. The guy installing the cams has a dyno so i should have results in a week or so. It should be quite an improvement.

PLT

$250 is a fair price for factory "E" cams in excellent condition
Be careful, "E" pistons have very shallow valve pockets. If the cam you choose is too aggressive the valve to piston clearance will be inadequate or non existent.

The most popular cam swap for the 911 E is the Solex cam. With the tight lobe centers (97) and added duration, you have increased lift at overlap. Lately I have been grinding the solex cam on a 102 lobe center. This is the same L/C as the 911 E and helps with the valve to piston problem. It also give the engine a wider power band.

Paul's car has a MFI injected 3.5, no shallow E pistons there.

Paul,
WHo's doing the work? David Brown?

Quote:

Originally posted by Tim Walsh
Paul's car has a MFI injected 3.5, no shallow E pistons there......

MFI injected 3.5, you mean like this??
http://forums.pelicanparts.com/uploa...1089734025.jpg

Close.. His has 69S stacks, K&N's with rainguards and an electromotive twinplug ignition.

That's a really nice setup, but if that's a 3.5 liter motor, then why is it singled plugged?

I've seen that picture before and it always confuses me. It looks like those are plain-jane MFI throttle bodies, but without the linkages or any aparatus to actuate the throttle plates. How does that work?

The picture was taken before the engine was finished. it uses a modified stock cross bar and linkage.
Twin plugging is over rated. This engine made 369 rwhp.
I've read that any engine over 3.4 should have twin plugs. Well, perhaps that statement is in error.
The money it cost to twin plug was better spent else where.
When we build race engine, twin plugging is one of the last things we do.

Henry, is the twin plug issue over rated because this is a race engine setup to run on high octane leaded race fuel or can the big bore high compression engines run on pump gas without twin ignition and fears of detonation?

Related Question:
How much, if any at all, does running a MSD with a bigger plug gap help to avoid detonation or the need for twin ignition?

TIA

Quote:

Originally posted by Shuie
Henry, is the twin plug issue over rated because this is a race engine setup to run on high octane leaded race fuel or can the big bore high compression engines run on pump gas without twin ignition and fears of detonation?

Twin plug is necessary if detonation is an issue or potential issue. High compression, high dome pistons that split the chamber, lean fuel mixture (smog engine), or low octane fuel. This engine only runs 10.5 to 1 which on a 100mm stroke 74.4mm bore and has a relatively flat piston dome. We also run 110 octane fuel and a special distributor curve that puts minimum amount of advance in until after we pass 4800. This gets us past max cylinder pressure with a reduced possibility for detonation.
BTW: we don't race the engine in the same trim that got us those phenomenal hp readings.

Related Question:
How much, if any at all, does running a MSD with a bigger plug gap help to avoid detonation or the need for twin ignition?

Anything that can help burn all the fuel (complete combustion) without too much advance will help. Will a large plug gap help? I don't know.

TIA

Quote:

Originally posted by Henry Schmidt
Be careful, "E" pistons have very shallow valve pockets. If the cam you choose is too aggressive the valve to piston clearance will be inadequate or non existent.

Agreed. To clarify, using an 'S' cam with E pistons can be done. However, sometimes it will work, and sometimes it won't (depending upon what machining you have had done to your engine parts). The piston to valve check is vital here.

If you do encounter a problem, simply enlarge the pockets in the pistons (no less than 5mm of material from the back to front of the piston).

-Wayne