Team Chevelle banner

voodoo 268 or 276 for my 468

  • Voodoo 268

    Votes: 21 45.7%
  • Voodoo 276

    Votes: 25 54.3%
1 - 20 of 27 Posts

·
Registered
Joined
·
1,146 Posts
Discussion Starter · #1 ·
I have an Engle 238 duration 540 lift single pattern on a 110 in my 468 now. It sounds great, pulls good, but has very little vacuum. #390 heads, ported, with small valves, old Wieand dual plane, nice worked Q-jet, TRW flattops, behind an automatic in a 75 Camaro. This car has to be streetable, and get decent mileage. I'd hate to put one in too small, but it has to go 50 miles round trip to the cruise spot (Winnipeg). Maybe a 3:42 gear out back would be a nice compromise, unless I keep the 4:56's and go an overdrive tranny. Your thoughts, gentlemen.
 

·
Registered
Joined
·
845 Posts
276 cam and put in some 3.73's. 28" tall tire you'll be cruzin just fine. That big motor won't see an improvement in mileage from the 268 to 276,if any its not nocieable.

How come 4.56's are out back? Did the car have a different combo before you 468? Gear swap is much cheaper and with that cam and your combo that would work better than 4.56's IMHO.
 

·
Premium Member
Joined
·
9,919 Posts
put the engine IN FRONT of the tranny.;)
 

·
Registered
Joined
·
1,146 Posts
Discussion Starter · #5 ·
How come 4.56's are out back? Did the car have a different combo before you 468? Gear swap is much cheaper and with that cam and your combo that would work better than 4.56's IMHO.
Yeah, the car came with 4:56's. Ya know, a 700R4 might be ok if you could just get it to live.
 

·
Premium Member
Joined
·
27,555 Posts
Personally, I'd focus on the gear change BEFORE considering a cam swap.
You should be able to tune that 238 Engle cam to provide more vacuum. What is the timing specs?
On a 110, it should't be too low...I would guess somewhere in the 12 in. range, especially with a Quadrajet.
My bro-in-law's Voodoo 276, 233/241 @ .050", pulls nearly 14 in a 383.
 

·
Registered
Joined
·
121 Posts
Until now I had a very similar cam in my 454. Also from Engle 238/244, valve lift .541/.559 and LSA 110*. It sounded really good and also pulled really good. But I also had very low vacuum (7" HG) with all the interrelated problems. I was told here in the forum it should have 10-12" vacuum in a 454, coudn´t find any problems on my car, no leaks, ignition timing ok, vacuum advance removed and modified, no help. Advanced it 4*, no help. I even pulled the heads now, also everything ok. Now I am installing a voodoo 60212 hyd roller and hope things will improve.
 

·
Registered
Joined
·
1,146 Posts
Discussion Starter · #9 ·
Yeah, too much gear. An overdrive would cure the problem. And ya know what--I don't have much for vacuum either! I think these Engle cams just have not got that covered. Sound absolutely delightfull, pull like ponies posessed, but no vacuum.
 

·
Premium Member
Joined
·
9,525 Posts
I think the 110 lsa has a lot to do with the lac of vac. my 110 lsa only had 5.5 in my 454
 

·
Registered
Joined
·
11,298 Posts
I aggree,238 dur @.05 is not that large of a cam for 468 cubes and possibly better tuning/dialing in is what needed here.

What is your current initital & total timing along with idle vaccum in neutral and then in gear if running an auto trans?

For example,I put a comp flat tappet hyd 292 cam with 244 deg dur @ .05 on a 110 deg l/s in my friends 469 pontiac (a little more cam in same size motor as your is)and it idles good with a slight lope/choppyness @ 900 rpm idle with approx 12-13 inches vacuum. That 292 cam pulls through approx 6,200-6,400 rpms before dropping off on power with his setup & it's very streetable in traffic in 469 cubes,but 244 deg dur @ .05 on a 110 deg LSA in a smaller 396 or 402 motor and that would be a different story for sure.


Scott
 

·
Registered
Joined
·
11,298 Posts
The 110 LSA could be part of the issue but maybe ENGLE is a bit off/inaccurate on their duaration @.05 measurements so there is actually more duration then they state,stranger things have happened over the yrs.

Scott
 

·
Registered
Joined
·
1,063 Posts
The voodoo 276 will give you enough vacuum for a 468. I had it in a 496 and I didn't notice any hindering of the power brakes due to poor vacuum. The power brakes worked as equal as the car with it's original 396 with the stock 325hp cam.
 

·
Premium Member
Joined
·
14,365 Posts
Just like Bill, and some others have stated, I'd change those rear end gears before changing the cam if I were you. If you want to focus more on gas mileage, then 3.55 gears would be in order, however, I'm partial to 3.73's with a 28" tall tire myself. But 4.56's w/out an overdrive trans is just too much for the street, and that's what's killing your gas mileage. I had 4.56's in a daily driver for three years and it was fine due to the O/D trans that the car also had. But 4.56:1 is too much gear for that cam anyway, unless maybe you're running a very low stall speed that you want to compensate for with the rear gear choice. The only reason that I had 4.56's in my daily driver was due to the car weighing a whopping 4,444 LBS with me in it, and having a very small V8 engine in it (namely 281 CID) so I really needed the gears to get the car moving off the line.
 

·
Registered
Joined
·
143 Posts
There's one thing people dont realize about the voodoo's. The advertised durations are rated at .0085 instead of the almost standard .006 that other companies are using. Comp uses .006 for their hyd profile adv durations. The 268 voodoo is actually 275 @ .006 if you want to compare the seat to seat numbers to a comp or engle. The ex is 280 @ .006.
 

·
Premium Member
Joined
·
17,954 Posts
I was thinking what Scott said. The cam has gentle take up ramps so the actual effective seat duration might be long. Combine that with a 110 , I asssume low compression and you get low vaccum. Most old GM cam shave the same seat issue, but sport 114-115 LSAs and were used with 10:1 minimum compression.

The Crane LS6 type I usd pulled 14" in a 433, it would pull 15-16"Hg in a 468. Solid though. F304. Still have the old cam on the shelf. But I used it in a 10.75:1 mill.

Go with the smaller VooDoo if you replace.
 

·
Registered
Joined
·
681 Posts
change the gear and get a vacuum canister.
Considering the large # of cams failures in recent years; especially on hydraulic falt tappet cams in BBC motors...I have to agree with above. Gears and installing a vacuum can is gonna be about as much as a cam with a lots less chance of any type of failure. dont get me wrong I think the VooDoo cams a greats...but not great enough to change and chance and failure when the one you have is working.

Oh yeah, terms such a decent gas mialge and BBC motors shouldnt be phrased in the same sentence. recently there was a post about milage and people were claiming Gas milage #s that rival new GM small block cars with fuel injection and weight 500 lbs less. I dont think so and would have to see it to believe it!
 
1 - 20 of 27 Posts
Top