TPITuned Port Injection discussion and questions. LB9 and L98 tech, porting, tuning, and bolt-on aftermarket products.
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is the comp cam 268XFI to big for daily driving...i have a L98....im looing for a cam with a noticable lobe for my daily driver along with performance....thx.....ohh and plz give recommendations for cams...ive done searches but havent found a whole lot on daily driver cams
__________________ Modded L98 in progress...in hopes of a 13 sec daily driver that can hang with an ls1....let me know if u have any ideas
i have a bigger cam, the 276 cam, and it was my daily driver for a bit. I also have a T-56 which makes a big difference. The key though is in the tune, which gets harder to nail down the bigger you get.
i was j/w cuz i saw the lift on it was like .570 ...so i didnt know if thats like too big or not....but if u had a bigger cam than that maybe ill go with the 268xfi
Well that cam is bigger than mine lift-wise, but not in duration nor LSA, so yours should be a lot easier to tune. Your gonna need some pretty hefty springs with that high lift.
I have that exact same cam sitting in my gargage. It is going into my engine. However like Ken said you need the heads to support the high lift. I'm also running 1.6 roller rockers.
I'm currently running a ZZ9 style cam and the advertised seat to seat is around 282 degrees and this is with 212 degrees at .50 lift. It idles quite well and by the way and is on a 112 degree lobe centers.
The XFI268-HR13 is 268 degrees advertised duration with a 218 degree duration on the intake at .050 and 113 lobe center. To me this is a "big" cam in a small package. It should idle quite nicely especially with the 113 lobe center and like Ken said with the proper tune.
This cam also has a smaller seat to seat duration than the GM LT4 Hot Cam and Comp Cams own EFI268-112 cam. This cam is of the latest design and was designed for a fuel injected motor. I like the looks of it.
I'm having a 4-bolt short block built up to change out the one I have and of course this cam will be in it. I should be able to have a report after the first of the year. Hoping to be well past the 304RWHP and using my TPI setup. Love that TPI. Shooting for over 400HP at the crank. Allen
__________________ Best of 11.57 and 115.73 mph(1811DA). Motor: Dart SHP block 368ci, AFR Comp 195cc heads, 11.1:1 comp, highly modified TPI 1st style SLP runners, moded GM plenum and First Injection TPI intake manifold, Mike Jones 3/4 race cam, Yank PT4000 converter, Dyno Don 1 3/4" shorty headers, Dyno Don custom exhaust, custom cold air intake, AS&M monoblade throttle body. Meziere electric water pump. Mufflex 3.5" exhaust catback. Magnaflow 3.5" muffler#12909. Kevin91Z Tune. 4L60E installed. Now 420RWHP, 417RWTQ with new motor.
Last edited by 1989GTATransAm; 10-03-2005 at 08:57 PM.
I picked the comp 268 xfi,Should be done sometime this month.heres The set up Vortec 350 4 bolt main stock bore,balenced. 9.5.1 pistons comp cam 268 XFI Roller comp magnum roller lifters L98 Iron heads 64cc screw in studs Comp 1.52 roller rockers Comp beehive springs Comp push rods comp double roller timing chaing Holley Stealth Ram Tpis 58mm throlle body 24 lb Injectors Harris stage 2 chip flowtech headers and y pipe borla cat back (no cats)
I have no idea how its gona run,or the numbers it will make. Im curiouse about how the l98 head will perform.any input is greatly appreciated thx.
If your asking me Ill be sure to make a video,its done just needs installed,itll be a few weeks,I wont get it back till the snow clears.
I may have my parts ordered by then I'm running alum l98 heads gasket matched comp hydraulic flat tappet xfi260 cam the 268 idle is lil rough for me comp 1.6 rockers block is bored .60 over flat top pistons had the crank turned over gonna get tpi ported and exhaust will be hedman shorty headers true dual 2.5 haven't picked mufflers yet and 24injectors, and planning on getting a custom tuned chip.