[DeanBenson]

I hate to start another cam thread, but I'd like a camshaft recommendation.

This is for a 64 Lemans convertible, it will be a street only cruiser, driven to work a few days a week on the interstate, local cruises/car shows. 2.93 posi, M20, Pypes 2.5, R/A manifolds, 65 Tri-power, power brakes, full roller rockers (ratio depends on what you recommend, I have 1.5s now). I want the engine to be all done by 5500 RPM and run on 89. We have 91 octane here now but...

I just bought a fresh never fired 75 400. +.040 TRW, XE262, recon stock rods w/ARP bolts, balanced, pistons are .015 in the hole (I've only measured one so far). It has fresh 6X-8 with no port work, stainless valves 1.77 exh.

I plan to ditch the 6X-8 and use my other fresh 6X-4's, they have some heavy bowl work done and are gasket matched. I plan to disassemble the engine and have the block decked and squared to about .005 down in the hole. I plan to mill the heads to achieve 9:1 static.

I was leaning towards a XE268 cam or a voodoo, before I started looking hard a Sandoval Performance's website and reading more about hydraulic roller cams. Now I'm torn, confused and tired of thinking about it.

I was looking at his L/C2 206/[email protected] 110 LSA or L/C3 214/[email protected] 108 LSA rollers or "the daily driver" 224/[email protected] on 108LSA

It seems that there are only positives with a HR, more torque, less wear, decent idle. Are there any draw backs to having a roller cam with the tri power? Will I see a big drop off in fuel economy with a high lift roller? I'd like to get at least 17 MPG if possible.

The more I read about XE versus VooDoo, I was leaning towards a VOODOO Part Number: 10510702
•Advertised Duration (Int/Exh): 262/268
•Duration @ .050 (Int/Exh): 219/227
•Gross Valve Lift (Int/Exh): .468/.489
•LSA/ICL: 112/108
•Valve Lash (Int/Exh): Hyd/Hyd
•RPM Range: 1300-5500

So what would you do? Is there a good HR that will fit the bill for what I'm trying to do? Or will the roller kill my MPG, (the reason I chose 2.93 axle). Am I better with one of the HFT? Which one?

I do not want a max effort, squeeze every hp out engine.

I've kind of steered away from the OEM grinds because of the low 9:1 compression. Should I just stick a 068 in and be done? I have a crower 60916 on the shelf but I don't think I have enough compression for it either.

Thanks for any recommendations and advice to help un-confuse me.

Dean

[steve25]

With those rear gears I would set up the heads to take 1.65 rockers and run the 068 cam or something close that would have the lift of the 1.65/ 068 combo with just running 1.5 rockers.
A 400 cid motor even with a stock 066 or 067 cam really needs 3.55 gears if the car weights in at over 3500 lbs.
the gears will make the car perform far better than the bigger cam and 2.90s can dish out below 4000 rpm!

[DeanBenson]

Yes I figured the 2.93 gears would be my limiting factor, that's why I'm trying to build a low end torque engine. Would going with a HR over a HFT help more or are the rollers really more just for high RPM and total overkill for my needs. I was looking at the smaller HR profiles for more low end torque.

Thanks for reply

[geeteeohguy]

I'm pulling a 2.56 gear with my heavy, automatic '67 GTO convertible, and it does just fine. It's a 9.3:1 400 (406) with an 068 cam and #15 heads (87cc with small valves). Stock intake and ignition. Not a ball of fire off the line, but no slouch, either, and a real terror on the open road. Cruising 75-80 mph and getting over 20mpg doing it doesn't hurt much, either. My firm belief that even in a stickshift car, a 3.55 gear isn't needed, and is a detriment to street driving. BTDT, and changed the gearing on my 389 powered '65 GTO to 3.36, and would have gone to 3.23 or 3.08 if the carrier would have accomodated it. Tall rear gears like 2.56-2.93's will do better with a low-end torque type of engine combo, especially in a stickshift car though, and a mild cam is a better choice. FYI, the tallest oem gear that Pontiac offerec for manual trans cars was 3.08.

[Cliff R]

If you get the SCR up to a true 9 to 1 the Lunati flat cam would be fine, IMHO. It's pretty short seat timing and wider 112LSA.

I wouldn't put a 108 or 110LSA small HR cam in that build for any reason, it will be happier all the way around with a small to moderate size cam on a 112LSA....IMHO.

[DeanBenson]

I should be able to get 9:1 Is this enough compression for an 068?

Is there a good 068 sized roller on 112 LSA? Or is a roller just not needed for what I'm building. I don't want to have to worry about cams going flat.

I've been playing with CAMQUEST and the torque/hp curves I'm seeing with CAMQUEST and comps XR264hr and XR276hr are adding about 30-40 hp and 2-26 ft-lb over the XE262. I'd like to have that extra power if it doesn't negatively affect driveability, or will the roller give a better idle and driveability?

XE262 366hp 441 tq 218 224 @.050 on 110 lift .462/.469
XR264 400hp 443 tq 212 218 @.050 on 110 lift .487/.485
XR276 410hp 467 tq 224 230 @.050 on 110 lift .502/.510

Anybody running a similar combo? It looks like geeteeohgy is similar but with 9:3 and a 068.

[Dick Boneske]

Dean, I made up a cam comparison sheet to help us with our 467 in the Firebird we're working on. We picked the Lunati Voodoo 20510711 hydraulic roller at the top of the chart.

It may be a little mild for our 467 with the big heads, but we were concerned about power brakes and streetability. Note the 112 degree lobe separation and just over .500" lift.

It looks to me that this would be ideal for your 400.

I didn't forget about your plating--likely going next week.

[DeanBenson]

Thanks Dick, I think the roller cam you chose may be a little big for my 400 with stock rods, rpm range 1800-5800. I like the next smaller grind Part Number: 20510710 rpm range 1400-5400.

I'm just wondering if the cost of the roller is worth it on my mild build. It looks like the roller really kicks up the torque numbers over a similar sized flat tappet. How much torque would I be giving up by running the crower 60240 HFT 210/221 .422/.446 on 112LSA?

Part Number: 20510711
•Advertised Duration (Int/Exh): 270/278
•Duration @ .050 (Int/Exh): 219/227
•Gross Valve Lift (Int/Exh): .515/.530
•LSA/ICL: 112/106
•Valve Lash (Int/Exh): Hyd/Hyd
•RPM Range: 1800-5800
•Includes: Cams Only
Previous Part Number: 60911


Part Number: 20510710
•Advertised Duration (Int/Exh): 262/270
•Duration @ .050 (Int/Exh): 211/219
•Gross Valve Lift (Int/Exh): .507/.515
•LSA/ICL: 112/106
•Valve Lash (Int/Exh): Hyd/Hyd
•RPM Range: 1400-5400
•Includes: Cam Only
Previous Part Number: 60910


Anybody have experience with the two voodoo rollers in a 9:1 400?

[jonmachota78]

If this is a new build It will be considerably cheaper for you to go roller up front than it would be to convert to a roller down the road. Fwiw