280XFI vs 292XFI
280XFI vs 292XFI Yep...another cam thread. I need some input to help me make up my mind. My setup will be/is 383 cid, 11.5-11.8 CR, heads flow in the 270s at .600 lift, ported LT1 intake, 58mm tb, long tubes, 3600 stalled A4, 3.89 9", 3400 lb car. I'm on the fence between the 292 xfi (242/248 584/579) and the 280 xfi (230/236 576/570). Comp has a cam help sim that I downloaded and ran with the above info. It recomended the 292xfi as did their cam help desk. I've seen a few in here that run the 292xfi but my fear is that its too big for my app. At the moment I am running a Comp 224/230 574/570 (1.6) on 10.4 CR with heads flowing in the 260s at .600 lift. I am leaning toward the 280xfi. I like the lift numbers on all three cams listed above but I was just wanting a bit more duration than my present cam. If there would be a better cam than the ones I have in mind, please edcuate me. I'm like everyone else, just looking for the best combination for the buck.
Mec
Mec
Mec
Last edited by Greaseymec; Jan 11, 2008 at 01:07 AM.
Trending Topics
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Launching!
Joined: Nov 2007
Posts: 271
Likes: 0
From: Moore Oklahoma
What kind of springs are you running? Also, what are your shift points and trap rpm? Stall speed? Did you have to use a small base circle cam? Sorry for all the questions Warren. Just got the engine out today and will be doing the teardown tomorrow. Hope to finish the short block by next week so I'm doing a little fishing! (info fishing that is) Thanks for all the replys. Keep em coming.
Mec
Mec
I just replaced my Comp 918s with PAC-1518s for this season, but haven't been down the track yet. Yes, my XFI-292 is custom ground on a small base-circle.
I had a Vig 3200 last season (1.48 to 1.50 60fts), but just installed a Vig 3600 for this season. I wonder what they will be now, possibly 1.40s? The Vig likes to be "flashed" off the line for the best 60fts.
Keep the questions coming!
WD
I've read a few blurbs about Caddy lifters. Do you know anything about them? At the moment I,m running OEM lifters with a Crane dual spring (10308) which advertise a higher spring rate than the 1518s. Do you think the old school "the stiffer the better" would help? I was thinking of using the 10308 with a lighter retainer that what comes in the kit.
Installed Height (in) 1.750 in.
Seat Pressure at Installed Height (lbs) 165 lbs.
Open Height (in) 1.110 in.
Open Pressure (lbs) 426 lbs.
I've read about and understand the science behind the beehive but, seems like it will take a stiffer spring to help control this cam. Your thoughts?
Mec
Installed Height (in) 1.750 in.
Seat Pressure at Installed Height (lbs) 165 lbs.
Open Height (in) 1.110 in.
Open Pressure (lbs) 426 lbs.
I've read about and understand the science behind the beehive but, seems like it will take a stiffer spring to help control this cam. Your thoughts?
Mec
While I have no experience with either of those cams I would suggest 4.10 gears over the 3.89s...With my set up which is a much smaller cam than the 292 switching from 3.73s to 4.10s got me 1.5 mph in the traps with a 28" tire...The 3600 is a good choice...I just had my Vig 3600 restalled to 4000 for next year...I'd stick with with the Engineer's recommendations for spring choice as he's one of the few who seems to have figured out the big xfi stuff...Good luck with the set up...
--Alan
--Alan
Thanks for the input Alan. The gear change will most likely happen after I get the new combo in and tuned so I can have a better idea of the gear I need to run. I kinda like my 27" QTPs so the gear will most likely be a 4.11. Fairly easy and cheep to find for a 9". Keep the info coming!!
Mec
Mec
