I need some help choosing a cam for my 383 with EFI. I hope you guys can give me some ideas and guidance.
My main question is would the Comp XFI 280 cam hyd roller (retro-fit for my block) would be a good choice for a daily-driver or should I step down to a custom 224*/230* cam. The Comp XFI 280 cam has specs of 230*/236* .576"/.570" (with the recommended 1.6 rockers) on a 113* LSA. I would be running 1.5 rockers (because that's what I have for now) which would give me .540"/.534" lift. The custom 224*/230* cam would probably be ground on a 112* LSA. Basically an XE XR276HR on a 112* instead of the 110*LSA. I've also thought about maybe using an XE XR282HR of 230*/236* .502"/.510" on a 112* LSA with some 1.6 rockers which would pump up the lift to .535"/.544".
I'm rebuilding my 383 for use in a true daily driver. T56 and either 3.42 or 3.73 rear gears. I'm looking for any/all creative ideas, suggestions, and thoughts. I'll outline what I've got below. The cam is the only item I don't yet have.
383 2 pc RMS, KB hyper 12cc reverse dome pistons (4.040" 385 actual), 5.7 Scat rods and 9000 series crank. After engine mock-up, I plan on having the block zero-decked to my rotating assembly. With the recommended 1003 Fel-Pro head gasket at .041" comp thickness and zero deck my compression comes out to a calculated 10.04-1.
Induction will be Accel SuperRam (unported) with Holley 58mm t.b., Holley AFPR, 30# SVO injectors, and my choice of either TPIS Big Mouth or Accel bases (I have both - best?). 89 MAF with the '165 ECM.
Heads are older non-Elminator AFR 190's (unported) of about 66cc chambers and the AFR valves. 26120 beehive valve springs will be used instead of the 26918 beehives because of the larger dia spring pocket of the AFR heads. According to Comp, spring specs are as listed: seat press 155# @ 1.880" open press 377# @ 1.280" with .590" max lift. This is the big-block hyd roller valvespring. I also have the matching titanium retainers along with the AFR rev kit. These valvesprings are over and above what Comp recommends for the XFI 280 cam. I got a killer deal on them. I also have the Comp Pro Magnum 1.5 3/8" roller rockers. I may jump to a 7/16" 1.6 rockers in the near future.
My calculated DCR with the XFI 280 would be about 7.8-1. I know this is a little lower than most people run but I'm looking at the times I may have to run the lower octane fuel. Dropping down to the 224/230 cam would increase my DCR to about 8-1. Would this be too high to run the occasional tank of 80 something octane gas?
Is the XFI 280 too big for a DD 383 as far as reliability and low (to mid?) 20's mpg's?
I will be having PCMforless burn me a start-up chip for this combo until I learn how and what to burn my own chips. I have what I need to burn chips but lack the knowledge as of yet. PCMforless has already said burning a chip for the 230/236 cam would be no problem.
I know this is rather long but I've tried to include all information. Please give me some ideas. Any guesses on possible HP/torque?
Thanks to all
My main question is would the Comp XFI 280 cam hyd roller (retro-fit for my block) would be a good choice for a daily-driver or should I step down to a custom 224*/230* cam. The Comp XFI 280 cam has specs of 230*/236* .576"/.570" (with the recommended 1.6 rockers) on a 113* LSA. I would be running 1.5 rockers (because that's what I have for now) which would give me .540"/.534" lift. The custom 224*/230* cam would probably be ground on a 112* LSA. Basically an XE XR276HR on a 112* instead of the 110*LSA. I've also thought about maybe using an XE XR282HR of 230*/236* .502"/.510" on a 112* LSA with some 1.6 rockers which would pump up the lift to .535"/.544".
I'm rebuilding my 383 for use in a true daily driver. T56 and either 3.42 or 3.73 rear gears. I'm looking for any/all creative ideas, suggestions, and thoughts. I'll outline what I've got below. The cam is the only item I don't yet have.
383 2 pc RMS, KB hyper 12cc reverse dome pistons (4.040" 385 actual), 5.7 Scat rods and 9000 series crank. After engine mock-up, I plan on having the block zero-decked to my rotating assembly. With the recommended 1003 Fel-Pro head gasket at .041" comp thickness and zero deck my compression comes out to a calculated 10.04-1.
Induction will be Accel SuperRam (unported) with Holley 58mm t.b., Holley AFPR, 30# SVO injectors, and my choice of either TPIS Big Mouth or Accel bases (I have both - best?). 89 MAF with the '165 ECM.
Heads are older non-Elminator AFR 190's (unported) of about 66cc chambers and the AFR valves. 26120 beehive valve springs will be used instead of the 26918 beehives because of the larger dia spring pocket of the AFR heads. According to Comp, spring specs are as listed: seat press 155# @ 1.880" open press 377# @ 1.280" with .590" max lift. This is the big-block hyd roller valvespring. I also have the matching titanium retainers along with the AFR rev kit. These valvesprings are over and above what Comp recommends for the XFI 280 cam. I got a killer deal on them. I also have the Comp Pro Magnum 1.5 3/8" roller rockers. I may jump to a 7/16" 1.6 rockers in the near future.
My calculated DCR with the XFI 280 would be about 7.8-1. I know this is a little lower than most people run but I'm looking at the times I may have to run the lower octane fuel. Dropping down to the 224/230 cam would increase my DCR to about 8-1. Would this be too high to run the occasional tank of 80 something octane gas?
Is the XFI 280 too big for a DD 383 as far as reliability and low (to mid?) 20's mpg's?
I will be having PCMforless burn me a start-up chip for this combo until I learn how and what to burn my own chips. I have what I need to burn chips but lack the knowledge as of yet. PCMforless has already said burning a chip for the 230/236 cam would be no problem.
I know this is rather long but I've tried to include all information. Please give me some ideas. Any guesses on possible HP/torque?
Thanks to all