jdnca1

572;

I run a 280/[email protected] 115CL with .730 lift in a 10.5:1 632. The problem you'll have if you try to run much more duration than this is it will be very difficult to make the motor idle below 1000. I would also not recommend trying any more lift than .730 ish because coupled with the spring pressures necessary, the lifters won't live (speaking from vast experience here) I would talk with Steve Tanzy @Erson for a cam recommendation, he nailed Wette Vette's and mine. I had so many lifter problems I recently switched to the Schubeck "radius lifters" (basically a high tech very hard material solid flat tappet with a radius to run on a roller cam lobe) My guess is your durations and lifts will be very similar to mine, but your CL might move to a 112. How hard do you plan on turning the motor? I have an Erson 276/284 @.050 with .730" lift on a 114 brand new in the box that would probably work perfect, it has the "pro-stock" firing order 1-8-7-3-6-5-4-2. I had this cam ground before I decided to go with the Schubeck program. I just about bet that is the Cam Steve will recommend you.

bob

JDNCA1/

You have some wild ramps on your cam. How hard do you turn the motor? I would be interested in hearing how your Schubecks work out. Merry Xmas.

jdnca1

Bob;

One thing to keep in mind about big inch motors is they like A LOT of cam. My previous cam had the same duration with lift approaching .800"...very, very aggressive ramps. (AKA lifter killers) Had to run triple springs that were 340# on the seat and around 950# opening. 280/288 is definately a big cam, but not like it would be in a 502. My motor will idle at 900-1000 and drops to about 650 in gear. Most of the reason I can make it idle is I run small carbs 2X775 race demons, a pair of 1050 Dominators would never work. The 115 CL helps the idle a lot as well. The motor actually wants more cam, I have it installed 2 degrees retarded. Any more duration though and the idle qualities would not be compatable with shifting a bravo. I turn around 6200 natural and around 6700 on NOS. The Schubeck stuff has been trouble free to date and makes BIG power. I took .050" lift out of the the Schubeck cam and left everything else alone, still made the same power. The lifters weigh half of a traditional roller lifter, you can run less spring, and there are NO moving parts to break. To run the Schubeck program you have to run a custom grind cam thats coated (different base circle, 1" vs a 3/4") tap the lifter valley to install the link bars (similar to Jesel lifters) and get new pushrods (shorter) which helps with deflection issues. I changed springs as well, now 270# on the seat with 750# opening.

Merry X-Mas to you as well.

bob

JDNCA1/

I spoke to Joe last year and almost ran his stuff. There were some questions on durability and what would happen to the lifter coating in the event a spring broke and the lifter started bouncing around on the lobe. I would be interested in hearing of people who have experienced 200+ hours with his lifters/hardened lobes. How many hours do you feel you will get before you have to address the lifter lobes or cam coating? Is it an expensive proposition to have the cams ground to a 1" base circle"? In your application, do you do much idling? No doubt, if you can run the inches and the cam profiles you have, your going to make some power! Thanx, Bob

572scarab

With this set up will my bravo be able to handle this as far as in & out of gear. I was planning on around 6000 to 6500 RPM.I am not sure of the RPM that it needs to be at.This high comp is a idea we are tossing around .My engine builder says we can do this! I belive him, He has built some pretty wid stuff. I just wanted to here some other opinions Thanxs Guys!!!!

jdnca1

Bob;

Believe me I was skeptical as hell and still need to see a lot more time before I am a complete believer. So far, everything Joe has claimed has turned out to be true. Ther is no power loss at all over a roller lifter and if anything a slight gain. My last set of roller lifters lasted 7 hrs, so anything beyond that is a positive. The first set went about 40 hrs on a slightly smaller cam and I think 50hrs is all I would expect with my combo. Joe claims he has circle track racers with 2 seasons on sets. I don't think the lifters will be an issue from a wear standpoint due to the rockwell being a 95, the cam would wear first. I will be happy with 100hrs, Joe thinks 200 before a cam change...Who knows? A cam and lifters runs around $1300. In my opinion if a spring breaks you have problems with either set up. I guarentee a standard roller lifter will self destruct in very short order taking the cam with it. The Schubeck could live (if it doesn't shatter) which would be my worry. If you look at your springs regularlly and check seat pressures every 30-50 hrs you should catch anything starting to sag. One spring to stay away from (at least in my application) are the Manleys, more often than not they will break before they sag.

572;
You should be fine on the shifting issue if you have the right combo; heads, cam, intake and carb. The Rpm band you are looking at is exactly where I try to run and will work great for a high CR motor. Feel free to PM me if you want some ideas and/or experiences. Wette Vette is a great source as well, his high CR 496 is nastier than many blower motors I've seen.

WETTE VETTE

I bet he would give you a good price too. That would be a real good starting point and with .025 to .030 valve lash you will be right at that .700" max lift for durability, and the duration is about right as well. Set your heads up with about 230 to 240 seat pressure and run a double spring like the comp 951 or the Isky. You will have great power to 6500 RPM and decent durability. That cam was designed by Erson to be easy on valve train components with gentle lash ramps for endurance and still put out the killer power of a solid roller. Make sure if you are going to do this to run enough head. 325 fully ported for max flow would be the smallest I would go. A fully ported 345 or cnc 355 Dart Pro 1 would be ideal. To crank a large pitch prop 6500 RPM with the 572 will require some healthy flow capacity. Keep in mind the high compression does a pretty good job keeping adequate torque down low, but to make big HP on top end you need cam and flow capacity which also includes good headers!!
Good luck!!

traviss

wette vette.. check your PM box..


Travis

blown1500

Hello Guys!
Hope you all had a great Christmas!!!
I have the discussion about compression motors vs blower motors or nos all the time! When you are trying to make the power you are talking about here with a normally aspirated engine, you must have some very good and EXPENSIVE components. A blower motor makes this level of power with much less stress on all the parts. You can use a smaller cam-by a lot-the heads don't have to be as good, idle is much better, engine life can be much longer, and many other positive factors.
If room is a factor, consider different blowers like Pro Charger. They can be put in some pretty small bays. If you must have a normally aspirated engine, make it as big as you can with less compression and use lower RPM-consider something like Sonny Leonard's 704. The initial cost of the blower will almost certainly be offset quickly by fuel economy and breakage costs. You can pm your phone number and I'll give you a call and we can discuss this at your convinence!
Have a great day!!