cam swap???

[ZmeFly]

i have heard of but didnt and or dont know anything about this.

people swapping the 260 cam in for the 240 cam saying is a bit of an ugrade is this true and why

anyone ???

thanks

james

[Mudge]

That may be a misnomer, since that was the beginning of the smog era, a larger engine doesn't always have a larger cam, but who knows.

Doesn't any manual out there list specs?

I think it would be a major PITA since you'd have to have new rocker arms regardless, so why not get something even better if your going to all the trouble...

[Phred]

This should clear up the muddy water a bit.

Phred

datsun l6 stock cam specs.txt

[ZmeFly]

since im not understanding the specs really represented here i have a question.

not much i see is different between the 240 and the 280

but the 260 cam is different just slightly

by the specs posted on this sheet for anyone that may know which is the better cam??

<a href=http://www.geocities.com/bruskiz/ZCamSpecs.htm target="_blank">cam specs</a>

[Mudge]

8º difference is definately a difference, but I'd have to input all the data into Engine Analyzler or Desktop Dyno in order to really see the difference, because the lobe may not be as aggressive.

I myself probably wouldn't do the swap, but on a budget it might be a nice modest boost in power. Most aftermarket cams vary from one model to the next by 10º. More duration means the valve is open longer, allowing more bleed off at low RPM (which is bad, this means power loss to some extent) but more top end power since there is more time to fill the cylinders.

I guess I FINALLY have something to put into these programs now to simulate the engine, although no headflow specs means I'm going to have to end up guessing, but its a start

Anyone have headflow specs etc?

[Phred]

Mudge,

Coming up with flow #'s will be very subjective. Which head? which valve size? Fresh valve job? 1,2,or3 angle? All these things and more make large differences in flow. However, flow development is normally started with a baseline. This would at least give you some #'s to put in your program. To save time, most head flow people will go for what they know works, then flow it, then touch up to optimize and balance the flow from port to port. then flow again, repeat if needed, till they get the #'s they know are best from experience. So, what I suggest is to call B.C. Gerolamy in Sacramento (916-922-7652) in your backyard! Very politely ask them if you could get some baseline flow #'s for a E88, N42, P79, or whatever they might be willing to offer. Make it sound like your a potential customer, and they might take the time to help you out. Afterall, its not like there giving away trade secrets. just baseline #'s. Good luck.

Phred

[Mudge]

Good points, and thanks for the info! I'll see what I can digup...