I am working on putting together a heads, cam, intake combo for my friends 91 Z28. Will this be a good set up for a daily driven car and what kind of 1/4 mile times are possable with this set up? Or should I change something? Protopline 180 heads. Holley stealth ram. Comp Cams XR276HR. 224/230, .503/.510

 

I would use a less aggressive cam than an XR276HR on a daily driver. That cam feeds my 383 pretty well, but when I had the same cam on my 350 the bottom end was a little soggy, even with 3.89 gears & 2800 stall.

 

My motor has all the bottom end you could ask for and I use that cam. It's the topend (above 5,300 that could use a boost) and your HSR should take car of that.

 

What would you use for a cam? He wants to have enough power to see a 12 sec time slip even if it's a 12.99.

 

Im thinking of the same heads and intake combo and was recommended the zz4 cam. The zz4 cam is good for the street and should be able to get your friend into the high 12's and still get decent mpg. This cam shouldn't be to big for the computer but will require some time chip burning since it is a SD ecm.

 

I run the XR276HR-12 in my Superram 383 motor. Its a weekend car. Its not a huge unstreetable cam but it is a bit big for a daily driver IMO. The cam does have the tendancy to surge below 1500 RPM, however I run a Vigilante 3000 RPM converter so it doesnt bother me. Gas mileage on the highway is real decent but around town it suffers.

You might want to look at the CC XR269HR-12 or XR264HR-12.

 

Well, I have a totally different opinion than most on what size cam is good for a daily driver. In my opinion, a 224/230 is a good choice for a daily driver 350. Of course, what i see as drivability is different than a lot of people on here. I know more than a few guys who are running at least a 224/230 in their daily drivers, and love it. They act just like any other car driving normally. Really its all in the tune. If you get the car tuned out right then it will act just like a car with a smaller cam. I am putting a 227/233 in my daily driver 355 I am building. :lala: I really wanted to go bigger but I had tailpipe emissions to worry with.

Really what needs to be looked at is what do you consider drivability? Do you mind having your car idle at or around 850 RPM at idle in gear? Yes, the 224/230 cam will make less torque at 2000 RPM but that top end pull that a HSR and that cam will pull will be mad. If you want tire squeeling torque possible at part throttle then go with a smaller cam that will have more low end torque. But trust me, that cam will make plenty of torque down low.

I have a buddy with that same 224/230 and a LT1 intake and from a stop w/ a 2800 RPM stall and 3.23 gears he absolutely blows away 1st and into 2nd gear. He is also running 12.32 @ 109.49mph w/ the # 1, 2, and 4 cylinders misfiring half of the time. :hail:

 

That is the real question. The XR276HR-12 can be used in a driver, there are alot of folks doing so, however it will be fussy, but not enough to make you regret it. I got mine to idle between 700-750 RPM.

There is an HSR 350 with a Hotcam running a 11.9 on this board as well. I would bet the Hotcam has better street manners.

Audio clip of my Superram 383 with XR276HR-12 at idle, Hooker Supercomp LTs and Mufflex/Spintech 3.5" to dual 3" out.
Audio Clip ~225KB

 

[QUOTE]Originally posted by OMINOUS_87
[B] I would bet the Hotcam has better street manners.
QUOTE]

I think they would idle about the same. What people fail to look at is that idle quality of a cam has more to do than duration at .050. the XE 224/230 is a 276/281 advertised duration cam. I have searched and can't seem to find the advertised duration for the hotcam but i am willing to bet it is somewhere in the same area as the xe276 cam because of the "lazy" ramp rates that cam uses in comparison to the XE lobes.

 

I hear too many people that put the LT4 Hot Cam in that like the cam but wish they had gone bigger. I don't want that to happen.

 

Then I would go for the 224/230 XE (xe276) cam. I thoroughly believe it will idle about the same as the Hotcam based on advertised duration. If you have any worried on that get the 276 ground on a 114 LSA.

 

What are the specs on the Hot Cam? how about the XE218/224?

 

Here are some specs on the cams off of www.sdpc2000.com

LT4 Hotcam 1500-6000 RPM
O-Lap: 218 / 228
Centerline: 0.525" / 0.525"
Lift (I/E): 112

XR276HR 1900-5600 RPM
Advertised Duration: 276
Advertised Duration Exh.: 282
O-Lap: 224/230
Centerline: .502/.510
Lift (I/E): 110°

XR276HR 2200-5800 RPM
Advertised Duration: 282
Advertised Duration Exh.: 288
O-Lap: 230/236
Centerline: .510/.520
Lift (I/E): 110°

Edit: Chris has a good point about getting the 224/230 ground on a 114 LSA. I never thought about that and may consider that cam when I put together my engine.