Yeah, I'm hopin that a PCM, air intake, an intake manifold, 52mm TB, Ported heads, and a 512 lift .208 duraion @.050 lift cam will make some power..not all R/T's are dogs huh

 

gforce
The new issue of the NLOC news letter has an article in it called "The magical life of the camshaft". and at the end of the article the author list the cam specs for both gen I and gen II trucks.
The gen II specs are .504 lift and 185 deg duration on the intake and .531 lift and 192 deg duration on the exhaust. No lobe seperation or int/ex timing numbers were given and I will assume the duration numbers are at a given valve lift. I'm not really sure how the duration is measured on an overhead cam engine. If those duration numbers are measured from seat to seat then it is a very small camshaft indeed and I would think that anything that Crane has to offer would be a big step up.
Dale

------------------
Black 00'
13.21 @ 105.24 so far
full weight, stock tires

 

BaBolt,

Where did you get the new heads?


Mark

[This message has been edited by Ak.Silver2K (edited 01-26-2001).]

 

Can somebody explain the concept of "regrind"? The term implies they are removing material from the lobes to change the profile, which is going to reduce the duration. How can that possibly increase performance? I suppose they could reduce the lobe height to give them more duration to play with, but then you have to change the rocker geometry (or whatever passes for a rocker arm in our heads).
Or am I way off and they are completely replacing the lobes?

------------------
Mark
'00 Lightning
'79+ Corvette

 

Mark_2kL

I'm guessing now. But, I think the lash caps might be the compensator for this. Maybe like a shim to raise lift and other things. I dunno'.


[This message has been edited by BadBolt (edited 01-25-2001).]

 

I purchased the heads direct from the Ford dealer and I buy all of the FRPP items from a source that I make reference to all the time. In fact someone else just listed his site after they asked me about a good place to purchase chrome wheels. What you must realize is that when the part are in current production the price is very good. When they go out of production you can forget about it. The one bad thing is that FPS and FRPP watch how items are moving and if the sales are hot the price gets "jacked". Case in point are the oval bore throttle bodies and the Lightning cylinder heads, six months ago they were a great buy. You can read all about the head price story at the Corral and other web sites.

 

BaBolt,
Do you know the approximate rpm ranges of these cams? How much more rpm will we have to run to take full advantage of them?

Thanks,
Jeff

 

BABOLT-
I like the 6-speed idea. My last truck was a '86 chevy step side: zz4 engine and i put the t-56 in that with 3:73 rear. The truck went real good, i just hope my lightning will go as well some day soon.

------------------
Bill
'00 white lightning-#2030 of 4966-4/6/00 thursday
muth mirrors,door number pad mod,
clear corners, super white; headlights,corners,fogs,
trenz billet upper and lower grills, billet 3rd brake light cover,
harley davidson bed cover,
JDM flip chip, JDM lower pulley, J.L. stage 2 ram air kit on order
more to come....
'00 harley davidson FLSTC tons of custom parts..
'99.5 nissan pathfinder le-stillen equipped
'88 toyota show truck(TONKA)
'91 toyota mr2 turbo
'00 yamaha banshee(toomy race kit/chrome pipes)

 

I thought the 4 valve heads wouldnt fit the L because of packaging issues. Has this changed?

 

Crane should be able to tell you the RPM range on their grinds and what effect it will have on peak power. I do not have all of the details. The issue with the 4 valve head is in the application of the Lightning intake manifold to it.

 

BaBolt,

The stock lift figures look pretty good. However the stock duration figures seem to be lacking. The Crane 211 duration figure seems about right for these trucks with what we've done and their weight, however, I don't like the loss of lift from stock that Crane puts up for the 211. The other 2 choices seem to be too much. Too much lift, or too much duration it seems.

If what Bad as L posted is correct, we also have an asymmetrical lobe design from the factory, which is usually the best way to go. Are Crane's profiles symmetrical like you posted?

Thanks.



------------------
Jim
Black '00
#1,757 built 3/30/00
Clear corners
J.L. Street program
J.L. Stage II ram-air
MagnaFlow Exhaust

 

2nd Lighting,

It is certainly believable that a cam can make a 50hp difference. On the L98 Tuned Port motors, one of the better manufacturers had a cam that made 45hp, and that was their mild cam. Corvette Fever tested that cam with no other mods and it made .7 difference in the quarter mile time. The more aggressive cam from the same company made .9 difference, and CF wasn't the only company to produce those results.

Don't get me wrong, I'm not to saying that the cam(s) for either the R/T or the Lighting will make as much difference as the ones for the L98. All that I am saying is that a cam can certainly produce 50hp.

[This message has been edited by Typhoon (edited 01-28-2001).]