Power Estimates?
Thread Starter
On The Tree
Joined: Feb 2023
Posts: 109
Likes: 59
I see. Well when I called cam motion they asked me what spring kit i was using. When I said the 660 btr platinums they knew exactly what I was talking about and knew what lobe they wanted to use. He asked if it was a daily or weekend car and then came up with the .646 lift number based on that information. Had the guys at tooley shim and set the heads up and pressure test so im confident everything should go well.
TECH Fanatic
Joined: Aug 2009
Posts: 1,845
Likes: 255
From: Coast of San Mateo County Between Pacifica & HMB
I think you could hit 670 crank hp based on my 393" that made 690 from 7100-7300 rpm, still 682 @ 7600 with similar pieces.
MMS LS3 Heads (TFS version), MMS FAST W/ Mid-Length Runners, 243/249 LLSR (HR = ~ 237/243 adjusting for lash),
115*+3* .680"/.650" with 11.7:1 comp, and 1 7/8" AR LTs.
Differences Dailey Dry Sump (worth 15-20). Big Bore 4.175" X 3.60"
My .02 on cam for your goals with that much N2O & Street Ability
Something like~ 239*/251* 114*+2*
Not a "Cam Guru"
Also definitely 2" headers if you have the room.
MMS LS3 Heads (TFS version), MMS FAST W/ Mid-Length Runners, 243/249 LLSR (HR = ~ 237/243 adjusting for lash),
115*+3* .680"/.650" with 11.7:1 comp, and 1 7/8" AR LTs.
Differences Dailey Dry Sump (worth 15-20). Big Bore 4.175" X 3.60"
My .02 on cam for your goals with that much N2O & Street Ability
Something like~ 239*/251* 114*+2*
Not a "Cam Guru"
Also definitely 2" headers if you have the room.
Thread Starter
On The Tree
Joined: Feb 2023
Posts: 109
Likes: 59
I think you could hit 670 crank hp based on my 393" that made 690 from 7100-7300 rpm, still 682 @ 7600 with similar pieces.MMS LS3 Heads (TFS version), MMS FAST W/ Mid-Length Runners, 243/249 LLSR (HR = ~ 237/243 adjusting for lash),115*+3* .680"/.650" with 11.7:1 comp, and 1 7/8" AR LTs.Differences Dailey Dry Sump (worth 15-20). Big Bore 4.175" X 3.60" My .02 on cam for your goals with that much N2O & Street AbilitySomething like~ 239*/251* 114*+2*Not a "Cam Guru" Also definitely 2" headers if you have the room.
I think cammotion spec'ed you a great cam for, and with a stalled auto you should be fine driving it around but it is going to be rowdy. It definitely isn't too big..it is pretty spot on and it'll help you smash your goals. You could still give up some cam size and gain better manners while reving to 7500 like NAVYBLUE was showing. His cam has 12 degrees less overlap, but retards the cam timing a bit to allow it to still breathe at high rpm.
The altitude does change things a little with regards to how much "power" you need. I expected your combo with that cam to run 6.20's NA assuming sea-level, but at that altitude you'll probably be more like 6.40-50's. Going from 6.20's to 5.50's doesn't typically need a 150-300 shot. Noprep you probably won't be able to spray all of it at the start though.
The altitude does change things a little with regards to how much "power" you need. I expected your combo with that cam to run 6.20's NA assuming sea-level, but at that altitude you'll probably be more like 6.40-50's. Going from 6.20's to 5.50's doesn't typically need a 150-300 shot. Noprep you probably won't be able to spray all of it at the start though.
Oh and I never guessed, but I'd figure maybe 640 flywheel. ~1.6 hp/cube is a good estimate for pump gas LS stuff that's put together well. Tbh as long as it has a good powerband and is strong, I always see nitrous engines as just a vessel for spray lol. You could make 550 or 750 you just spray the difference.
Thread Starter
On The Tree
Joined: Feb 2023
Posts: 109
Likes: 59
To answer both of you, hopefully i can get closer to 700 crank out of it ~1.7hp/ci. It will likely take around 850-900 crank to get into the high 5s and low 9s out here at 3400lbs race weight with driver and gas. As far as torque, I was looking to make peak torque around 5000 and whatever it makes it makes. With an unlocked converter and dyno parameters the torque number will on the chassis dyno will likely not give a good depiction of what the engine makes to the crank. The current combo I have with a much smaller 236/245 cam and as cast 225s, msd manifold 11.3 scr made 470 wheel and 430 torque and only ran out to 6300rpm. Runs a 7.2 NA on average with a 1.59 60ft and a 6.6 with a 1.49 on 150 spray. I want to shift the torque curve up, spray into the 1.3 - 1.4 shorts and aim for anywhere is the 5 second territory. At no prep events this should be enough to be competitive in the small tire non-W classes.
Oh, and nitrous will be progressive. Likely a 200 shot over 1.5 - 2 seconds or so. Depending on track conditions. The track and street get really dusty over here so conditions can change quickly.
Oh, and nitrous will be progressive. Likely a 200 shot over 1.5 - 2 seconds or so. Depending on track conditions. The track and street get really dusty over here so conditions can change quickly.
