Hey guys, I've recently come to a point where a cam swap might be needed in my near future. I was using comp cams programs and it recommended the 268XFI HR13 for what I have now, and what I plan to have in the future (very convenient). Unfortunately, I've hit a snag financially, so this will be a build as I go type engine. Please note: Other upgrades are intended, such as heads and intake manifold, as well as drivetrain changes, they're just not intended within the next few months due to financial constraints.

Currently, my engine (L98) is almost completely stock. It has a different exhaust system, but stock manifolds (however, a set of hooker long tubes are sitting in my garage itching to be installed) It has, from what I know, the same 083 heads that came stock on these engines. The intake tube is also a PVC creation with new 'hi-flow' filter. The injectors are brand new Bosch III 22lb injectors (why I didn't buy the 24lb, I'll never know). I do have an autoprom and have been tuning with a good learning curve, so that's not an issue.

I'm curious, as to what kind of performance gains I would see from replacing the stock camshaft with aforementioned camshaft on a mostly stock set up. (I would put money on 15 to 25hp, going against camquest6's very liberal "50"hp)

Of similar importance, I'm also curious as to what driveability issues I will have running that somewhat aggressive cam in an otherwise stock set up. It's also the stock torque converter stall, and the borg warner rear end with 3.27 gears. I do little city driving, most of the time the car is going between 45 and 75mph

(Sorry this is a long post)
Unfortunately, I'm fairly certain the #8 intake lobe of my camshaft has been rounded off. I recently replaced the cam with another stock camshaft, and as much fun as it is, I would hate to keep swapping camshafts around as I build my engine up to where I want it.

Also, how does this cam do with say a 100 or 150hp shot of "just in case"? How would it fare with a T-56 (assuming I'm a competent driver)

Future upgrades include: AFR 195s, Holley Stealth Ram, Hooker long tubes (as soon as I obtain the rest of the piping), higher stall torque converter OR T-56. This car is a daily driver, but I would like it to give most of the newer cars a run for their money (C6 corvette not included)

Thanks for reading all of that, and thanks for your help.

Edit: Post was previously about an XR270HR but I feel (through my own and others opinions) that the 268XFI HR13 would be better. Hopefully that eliminates confusion from the below posts

 

For some reason, I skipped over the LSA of this cam... 110deg might be a little much for my 730ECM. Would a 268XFI HR13 Be a better choice? For those not interested in looking it up:
XR270HR:
----------Int--Ex
Dur: -----270 276
@0.050: -218 224
Lift: -----0.51 0.51
LSA: 110deg

268XFI HR13
----------Int--Ex
Dur: -----268 276
@.050: --218 224
Lift: -----0.57 0.565
LSA: 113deg

I understand I will have to get the 083's cut for the lift, but that wont be too bad.

 

i would imagine the 268 being better overall. i mean it has higher lift, slightly less advertised duration, wider lsa, same price, and passes even cali emissions. I see no area in which the 270 is better. but that's just me

 

Yeah, that's what I was thinking. Now, the same questions in my first post, but with the 268XFI (Performance/driveability issues on mostly stock L98 until I can upgrade the rest)

I don't have emissions tests to pass where I live fortunately, but that doesn't mean I want to pollute the environment intentionally haha.

 

The XFI is the better or the two cams. Performance UP; no drivability issue; excellent vacuum for brakes; noticable idle. In line with the HotCam as far as duration, but more lift and much better ramps. Biggest I'd go with a 350/355 streeable engine without entering the area where some negatives begin to kick in.

It's a SWEET cam!

Just my views.

Jake

 

How will it affect driveability on stock L98 heads/tpi? (083 casting I believe)