Voodoo lunati cams?

[kirkwoodken]

My engine is a typical 406: 10:1, stock 4 bolt block, AFR 210"s, roller cam, original Bill Thomas modified Rochester FI, 5.7, stock crank. CC rollers and rockers. Locally cut convertor stalls at 4400; ignition is an antique Delta Mark 10-B, purchased in 1968. It's been on at least 5 cars and I've replaced scr's twice, and put a smaller main capacitor in it so it revs a little better. T-Brake 400 Transmission was also built by local guy, Ken Duncan. No problems yet.

I pulled the engine about a year ago, just to see how everything looked, and found a lengthwise crack in one cylinder about 1 inch from the deck. I have a different block ready, but it isn't back together yet. The car is only a toy so it doesn't get much use. The first iteration of the 406 was with Dart II CI heads. Cam was CC 300 street roller, 255/255 110 LSA, .550" lift. While it made great torque, it fell on its face at higher rpm, most likely the result of a single pattern cam and a poor exhaust port. That engine made 455 RWTQ on Bob Steigemeiers chassis dyno. I don't know how much the torque convertor skewed the results. I feel 455 is a good number for a street style 406. I took Bob's advice and got heads with better exhaust ports.

The reason I went to the chassis dyno was to set the mixture on the Rochester. When I arrived, Bob called four of his friends so they could see what a Rochester FI looked like. Mine was the first he had seen. Once the R/L stops were set, the fuel curve was very good. Bob said he had always heard the Rochester's were inferior, but mine looked pretty good. I later had Bob flow the FI and it lost about 20 CFM in port flow.

My goal was to build basically what Duntov wanted in the Corvette in 1963; but the bean counters wouldn't allow it. Bill Thomas carried the ball by putting 383's with Rochester's in the Cheetah's. I bought my FI from John Ippert in 1970. John duplicated the Cheetah engine for his 63 Corvette, using, IIRC, Racer Brown's ubiquitous 66R.

Hope I haven't wandered too far.

[pdq67]

I personally have ridden in a '58 "Vette ragtop that had a mildly worked over '64, 375hp/327 FI engine, trans and 3.08 reg's under it and I'm here to say that the sucker with no more than an old Isky Z-30 solid lifter cam along with 2.5" dia. x 6" long pipe nipple dumps straight down off the rams-horns would flat haul the mail!!

As for a Rochester FI now, I would get hold of the guy up at Southbend, IN and talk to him. Jack Podell??

pdq67

[wyrmrider]

Which FI do you have
the early one or the later one
NICE

[Bob Hollinshead]

My engine is a typical 406: 10:1, stock 4 bolt block, AFR 210"s, roller cam, original Bill Thomas modified Rochester FI, 5.7, stock crank. CC rollers and rockers. Locally cut convertor stalls at 4400; ignition is an antique Delta Mark 10-B, purchased in 1968. It's been on at least 5 cars and I've replaced scr's twice, and put a smaller main capacitor in it so it revs a little better. T-Brake 400 Transmission was also built by local guy, Ken Duncan. No problems yet.

I pulled the engine about a year ago, just to see how everything looked, and found a lengthwise crack in one cylinder about 1 inch from the deck. I have a different block ready, but it isn't back together yet. The car is only a toy so it doesn't get much use. The first iteration of the 406 was with Dart II CI heads. Cam was CC 300 street roller, 255/255 110 LSA, .550" lift. While it made great torque, it fell on its face at higher rpm, most likely the result of a single pattern cam and a poor exhaust port. That engine made 455 RWTQ on Bob Steigemeiers chassis dyno. I don't know how much the torque convertor skewed the results. I feel 455 is a good number for a street style 406. I took Bob's advice and got heads with better exhaust ports.

The reason I went to the chassis dyno was to set the mixture on the Rochester. When I arrived, Bob called four of his friends so they could see what a Rochester FI looked like. Mine was the first he had seen. Once the R/L stops were set, the fuel curve was very good. Bob said he had always heard the Rochester's were inferior, but mine looked pretty good. I later had Bob flow the FI and it lost about 20 CFM in port flow.

My goal was to build basically what Duntov wanted in the Corvette in 1963; but the bean counters wouldn't allow it. Bill Thomas carried the ball by putting 383's with Rochester's in the Cheetah's. I bought my FI from John Ippert in 1970. John duplicated the Cheetah engine for his 63 Corvette, using, IIRC, Racer Brown's ubiquitous 66R.

Hope I haven't wandered too far.

Very very cool!

[kirkwoodken]

[quote="wyrmrider"]Which FI do you have
the early one or the later one
NICE[/quote]

TTBOMK, Thomas only modified the late model Rochesters. Mine is a 1963 375R. .018" nozzles and a .141 spill restriction. This puts the ratio lever in the middle of its travel with my size engine. For those who know nothing about these FI's, they will pump enough gas for 900 HP. Pump pressure can be as high a 400psi. They will not move enough air for 900 HP. Steigemeier tried to talk me into putting some nitrous spray bars over the air intakes. Maybe in my next life. It has been a fun project. My big fear is the float sticking, having a fire and melted blob where the Rochester used to be. The Rochester designer, John Dolza, designed FI systems for fighter planes in WWII. The metering system is like a giant Pitot tube, measuring impact air and pressure/speed on the side walls of the intake tube. As such, it automatically adjusts for variations in atmospheric pressure and density. The sophistication is hidden under a cloak of simplicity that many never seem to recognize. It is a Hilborn with a pill adjusted by air flow. The Rochester FI dual points distributor will go 8000 RPM without point float. Grumpy ran one in his early 331 cars. The old FI's are clean running, stumble free, smooth driving and idling, great mileage makers. The Rochester operating system could have been adapted to ALL GM gas powered products, improving mileage and emissions twenty years sooner.

I believe Kinsler bought the late model Rochester dies. He makes an intake manifold for them.

A 375 HP Vette would run mid 12's with headers. Don't remember what rear gears, but I would guess 4.56's-4.88's. That 2.2 first was a stinker.

[Sky rocket]

A few weeks ago, Cam King stated he considered the Voodoo line of cams, designed by his competitor, Harold Brookshire, to be the best series of off-the-shelf cams. If you are wanting EXPERT advice on off-the-shelf cams, this is it. No need to look further.

I'm running UDHarold's old Ultradyne UR10-UR15; Lunati's 501C2LUN. 255/263, about .630 lift IN with 1.6. 1.5 on exhaust. 109 LDA. I think it is 173@.200" lift. This is a strong Pro Street type roller that will peak at about 7000 RPM or higher in your engine. I have it in front of a 4400 stall convertor. Performance is brisk with 3.31 gears. I have no idea how well it would work with a stick, and my engine is a 406. This cam is also made on a 106 LDA as the 501C1LUN. You can get it from Lunati or Bullet, both good companies in my experience. Cam idles at 1200 rpm in my engine. Can hear at "501C2LUN" on youtube. I attribute the misses to year old gas. Induction is 1963 Rochester FI. Stock Douglas muffler.

From what I understand below this cam http://www.lunatipower.com/Product.aspx?id=1995&gid=290 is the modern versoin of the 501C2LUN.

quote
The 288/296R6 was UltraDyne's most famous cam.
288/296 at .020 255/263 at .050 176/183 at .200 .626"/.626" valve lift, .026"/.026" valve lash.
The 289/300R5 was its' bigger brother.
289/300 at .020 256/267 at .050 179/187 at .200 .638"/.638" valve lift, .026"/.026" valve lash.
The 288/296R6 is available from Lunati as their 501C1LUN, or from Bullet under the old name. The 289/300R5 is available from Lunati as their 501C4LUN, and again, from Bullet as the 289/300R5. Ask for Steve at Lunati or Tim at Bullet.
If you want a much better one(those are 23-27 years old!), I have a 283/291 at .020, 255/263 at .050, 180/186 at .200, and .625"/.625" valve lift, .016"/.016" cam. It has so much bottom-end that I have been cutting most of them on 108 LSA to help hook them up. I also have similar cams with .645", .660", and .682" gross valve lifts.
Bob West on Team Chevelle has a 283/291R8 in his 505 cid, 3880-lbs Chevelle, and I believe he's running 10.40s or a little faster.

UDHarold

[Kdub]

Hi Guys,

I'm looking for a new cam for my 388ci street engine, Is there anyone one here using those lunati cam profiles in their steet engines? I would like to bleed off some lower rpm TQ for a stronger top end.

http://www.lunatipower.com/CamSpecCard. ... mber=60133

http://www.lunatipower.com/CamSpecCard. ... mber=60134

Lunati recomened me the first profile.

Engine spec is in my signature

Thanks

With the 10.5:1 compression and EFI, I would pick the first cam on a wide lobe separation like a 112 or maybe even a 114.

[Sky rocket]

Hi Guys,

I'm looking for a new cam for my 388ci street engine, Is there anyone one here using those lunati cam profiles in their steet engines? I would like to bleed off some lower rpm TQ for a stronger top end.

http://www.lunatipower.com/CamSpecCard. ... mber=60133

http://www.lunatipower.com/CamSpecCard. ... mber=60134

Lunati recomened me the first profile.

Engine spec is in my signature

Thanks

With the 10.5:1 compression and EFI, I would pick the first cam on a wide lobe separation like a 112 or maybe even a 114.

What are your thoughts behind that??

[Kdub]

The duration numbers look more streetable to me on the first one. The second one looks pretty aggressive for a 10.5:1 motor in a street car. The wider LS tends to be more EFI friendly and will help to shed off some torque on the bottom end and help extend the rev range.

[wyrmrider]

Based on skyrockets post above it looks as if the lunati profiles are 23 years+ old
Best to be talking directly with UD Harold or Mike Jones
Have an estimate of your head flows, bore, stroke, rod, exhaust, intake available when you call (jones )or include in an e-mail (udharold or call)

[kirkwoodken]

Something you need to consider is your base circle. If it is standard, about 1.030" on SBC's, your valve timing will be similar to what appears on the cam card. If you order a small base circle for rod clearance, you MAY need to move up to the next higher grind, as the small base circle will change the timing and duration somewhat. Typically, (There's that word again) small base circles make the cam smaller by 2-4 degrees in some areas. I'm sure Cam King will correct me, as this has been a topic in previous posts. The point is: timing will differ with base circles and roller diameters outside of the original design criteria.

Just to clarify, base circle is dependent on lift. On most cams, the cam nose has just a few thousands clearance from the bearing bore. When you get a small base circle, the nose of the cam is lower.

[Sky rocket]

Something you need to consider is your base circle. If it is standard, about 1.030" on SBC's, your valve timing will be similar to what appears on the cam card. If you order a small base circle for rod clearance, you MAY need to move up to the next higher grind, as the small base circle will change the timing and duration somewhat. Typically, (There's that word again) small base circles make the cam smaller by 2-4 degrees in some areas. I'm sure Cam King will correct me, as this has been a topic in previous posts. The point is: timing will differ with base circles and roller diameters outside of the original design criteria.

Just to clarify, base circle is dependent on lift. On most cams, the cam nose has just a few thousands clearance from the bearing bore. When you get a small base circle, the nose of the cam is lower.

Thanks, I have a standard base circle cam, I have no issues with a 3.625 stroke crank.

[greywolf]

Something you need to consider is your base circle. If it is standard, about 1.030" on SBC's, your valve timing will be similar to what appears on the cam card. If you order a small base circle for rod clearance, you MAY need to move up to the next higher grind, as the small base circle will change the timing and duration somewhat. Typically, (There's that word again) small base circles make the cam smaller by 2-4 degrees in some areas. I'm sure Cam King will correct me, as this has been a topic in previous posts. The point is: timing will differ with base circles and roller diameters outside of the original design criteria.

Depends on what machine grinds it, correct???

[wyrmrider]

kirkwoodken's analysis is correct no matter what kind of cam grinder is used
going to a small base circle also makes the nose smaller and increases the pressure on the components
going to a larger base circle- like going to a LS, reduces the strain on the nose
go to a larger base circle not only to get more lift but to reduce the strain on your cam lobes over the top
BBC "cam tunnel" mod or larger
Most grinders have new grinds for LS sized base circles...
Buicks have smaller base circles stock.
A good grinder will have special lobes for buicks and small base circle Chevy's
or use one of their more conservative grinds
Esample
Back in the Day Chet had different special grinds for the 4 and 4 1/4 stroke small block Chevy's in the twin engine cars (400 and 452 cu in). Springs and Heads were very limited and to keep nose pressure down with the small and smaller base circles durations ended up longer.
Loosing bottom end was not a problem as the tires would just go up in smoke with more.
Everything is different today CMC heads etc. I think you can do better than 20 year old grinds.

[cpmotors]

Never mind thanks anyway.

Yep the whole thread became absurd when you were looking at a simple 383 build and the Chrysler came in!!!

How do threads go off coarse so much guys?????

You missed the Off Ramp?