Scott Hamel

Lunati

276/284 522/539 cam

what i read about cam (400-455 c.i. vehicles. Will need 9.5:1 or better compression, 2800-3000 stall speed converter and 3.42-3.73 gears. Cam has a very rough idle quality!)

i'm using Lunati's valve springs , lifters and timing chain.

air gap intake

2700/3000 stall ACC

COMP CAMS OLDSMOBILE 455 MAGNUM ROLLER ROCKER ARMS KIT 1.6

holley 750 Double pumper

car already has 373 gears

it's all being stuffed into a 68/69 Olds 455 with "C" heads. come out of a Toronado it's got around 10 to 10.5.1 comp.. has hooker headers with 2 1/2 full going though flowmaster super 10s. i did upgrade to HEI also. i'm not looking for a 10sec car just a nasty street car.. i mean it already goes pretty damn good.. but could go better with some work.. i will be bringing the car to NH to run the 1/4 maybe 3 or 4 times a year.. hoping to get my boat into the mid 12s its a fully loaded 73 cutlass

what do ya think?

DeltaPace77

Idle shouldn't be to bad, as running a very similar Crane grind H-238/3347 in my 455. Did have Crane move LSA up a few degrees, for less overlap and better idle. Everything's quite similar to yours, 3.73 axle, and good exhaust. Also MSD multi-spark ignition. Has a vacuum canister to help out, but idles decent, with all accessories working fine. Another thing. Crane Hi Intensity flat tappet lifters, that bleed down some, at lower rpm's, and adjustable valvetrain.

ah64pilot

What I see is a basically stock 455 with a bigger cam, an air gap intake, and 3.73 gears. Have the head gaskets ever been changed? If so, your compression could be less than you think. Your carb is about perfect. Anyway, I could see low 13's out of it...maybe some 12's with slicks.

IMO your exhaust is a little on the small side, with a bigger cam and long tube headers you could get away with 3". It would also give you some room to grow into. I think you'll have a strong performer but it wouldn't be a "nasty" street car in my eyes.

Scott Hamel

i'm installing a adjustable valvetrain with the comp kit. the only thing i mite add NEXT year because i've spent So damn much on the motor this year is Aluminum heads.. but there going to have to wait awhile.. i already have a arm and a leg into this car ..lol

Scott Hamel

no not as ''nasty'' as yours.. i just dropped over $500 bucks on a full exhaust.. so 3'' is going to have to wait.. my motor only has like 75k on it.. its never been apart. stock 455? its not a junk mid 70's smog motor.. i think its one of the better builds olds put out. i'm working with a stock bottom and "C" heads for now.. i'd really like to drop a set of Alum heads on her.. but thats not going to happen this year.

ah64pilot

I think you're off to a great start...you're going to be happy with it. And think, driving it like this for a year will allow you to get used to it. When you add something else it won't be as much of a change to YOU, the driver. But it will be a big change to the overall performance of the car. Good luck!

captjim

If those duration #s are at .050, that is a LOT of cam for a driver. I would go a bit smaller, something like an old-school Engle 20-22 (226/230, .496/.502, IIRC) It should sound and run good, have decent idle and manners (that other cam probably won't). High 12s with M/Ts should not be a problem. IMHO.

EDIT: OK, I see that is the Voodoo cam,
http://www.lunatipower.com/Product.aspx?id=2350
I wish you guys would post complete specs and part numbers when asking for advice. That would work OK, but I think you would be better served with less lift.

DeltaPace77

Honestly, if the engines out now, and your planning on heads later, I'd really find a way to fund them now. Lot's of work to do twice, not to mention cost of new gasket's, ext. Also, if planning a head swap with the engine in the car, really a pain. I've done this before, and way easier on an engine stand.

cutlassefi

Quick and short;
Carb is too small for a dual plane intake.
Cam needs more lift and less duration if you're ultimately going with better heads.
I'd double check to see what your compression really is.

Scott Hamel

yeah sorry about the cam post but i did say it was Lunati 276/284 522/539 cam. as far as the carb goes i think that the 750DP will do the job i can always mess with jets etc.. as far as compression from what i've looked up and know about the motor its as stated.. 10 to 10.5 i know the motor came out of a 68 or 69 toronado.. for the life of me i can't remember if it was a 68 or 69 toro. i know its a low miles motor thats never been apart. as of right now i still have the C heads on it and the lower toro intake and this mill moves my 73 cutlass very nice..

Scott Hamel

the engine is still in the car .. i agree it would be easy on a stand. i don't mind the work..

Scott Hamel

Manufacturer's specifications for toronado mills


Engine: 1966–67 - 425 cu in (7.0 L) OHV V8, 1968–70 - 455 cu in (7.5 L) OHV V8
Power: 1966–67 - 385 hp (287 kW) @ 4800 rpm, 1968–70 - 375 hp (280 kW) @ 4400 rpm, 400 (298 kW) @ 5000 rpm with option code W-34
Torque: 1966–67 – 475 ft·lbf (644 N•m) @ 3200 rpm, 1968–70 – 510 ft·lbf (691 N•m) @ 3000 rpm, 500 ft·lbf (678 N•m) @ 3200 rpm with option code W-34

i just called my buddy who helped me pull the 455 and he said the car was a 1969 toro GT.. he has the carb that came off the motor on his 454 chevy. i think it was like 850cfm?

VORTECPRO

Carb is too small for a dual plane intake. And that is good advice.

cutlassefi

I think that if it's stock you have 9.75:1, at best.
Regarding carb size, see my dyno test of a 10.0:1 iron headed 455 with a similar size cam and a Performer and RPM air gap. It clearly wanted more than the 750 it had on it.

But it's your build, just trying to help. I'll say it again though, considering your ultimate goals, still the wrong cam.

VORTECPRO

Can you put up a link to that dyno test?

captjim

My little 355 has a 770 on it. IMO, olds engines "like" big carbs.

cutlassefi

https://classicoldsmobile.com/forums...parison-4.html

z11375ss

So what size carb should he run? I'm running a 780 dp and it seems to be enough but I certainly don't want to leave anything on the table. I have almost the same cam and compression is 10.25 to 1. Edelbrock heads, air gap, msd, hooker, 2 1/2 exhaust.

cutlassefi

Minimum 830cfm for a dual plane, 750 or so for a single plane.

z11375ss

Ok then, time for a new carb!

jfb

I use a 850 double pumper with a cam a little more lift then yours and about the same duration but not much more believe me dude it likes with proper jetting and power valve to run rich think about that and i have over 11 to 1 compression and that needs more fuel flow and it still is rich with just about on the border jetting.

VORTECPRO

Hold on, lets explain why "any" dual plane intake likes a big carb, with a single plane intake oviously you have an open plenum which all 4 bbls can feed the engine. A dual plane intake splits the engine in half, especially with a divider, which only lets 2bbls feed each side of the engine, this why a dual plane intake likes more CFM.

z11375ss

Thanks for the info guys. I always like to learn as well as teach. I'll go with an 830 and bring it back to Straightline and put it on the dyno and see what we can do. I have an excellent tuner who will be able to really dial in the carb. I thought for sure a 780 would be enough. To the flywheel the engine is putting out about 435 horse and about 575 torque. Good, but not great. See my clip under dyno pulls withthe 455. In the clubhouse.

DeltaPace77

Not sure about Scott's carb, but mine has a properly tuning Q-Jet, to my build application, with Performer dual plane intake. Thing really runs. Maybe a bit more than some, as has Dave Smith cc'd, ported/polished heads, and TRW forged pistons. Everything's set up for 10:25 compression. Looking at the Lunati page, looks like Scott's cam, averages about 235 degrees duration @ 0.50", with over .500" lift, and about big as I'd care to go on a street engine. Mine's also mated to a 700R4 od tranny, with nothing special about the converter stall. Idles decent around town, and cruises on the highway really nice. Also Scott, while know you're doing what you can, really recommend you pull the engine. I have an engine picker, stand, and only way I'll do it any more. Good listing your location, as maybe some here could help out. Pulling an engine, sounds like a big deal, but really not. Do it, all the time.

z11375ss

I agree, easy.

ah64pilot

Do you know the specs of your cam? I ask in your other thread but you haven't responded. I was just wondering because your car has a nice lope to it.

I saw your dyno thread, it looks like you made 347 HP and 459 TQ to the rear wheels...not bad! What are you figuring your drivetrain loss is to get 435 / 575 at the flywheel? Did you guys use 20% or 25%?

cutlassefi

Steve, do you not own a calculater?

435x.8=348
575x.8=460

Just a hunch but I'd say they used 20% as a factor.

jfb, try using some punctuation on your next post. It doesn't have to be perfect but your posts are currently unreadable imo.

Thanks

ah64pilot

Well I was close, I was trying to figure it in my head. I'm just wondering why so much...20% for a 4 speed car is a lot isn't it?

Scott Hamel

so i should go with a little less cam and more carb?

cutlassefi

Yes. And something to consider, typically it comes down to an actual consistent Hp number, not always a % so to speak.
Scott- yes, I'd use something around an 850 and a cam like I did for real57vette. His combo is very very similar to what you're targeting. We did a 228/236 @.050 on a 110 with .568 lift on both.
Thanks.

Scott Hamel

After it's all put together, i was going to send it to Karl's East coast speed for a dyno tune. if it needs or makes a lot more power with a larger carb he will let me know.. and gladly sell me one..lol he has lots of rebuilt carbs and i could trade my 750 in with some cash for the right carb.. as far as cam goes this was my close second

http://www.lunatipower.com/Product.aspx?id=1723&gid=287

Scott Hamel

i would also get a little less converter 2400/2800 stall if i went with this cam

http://www.lunatipower.com/Product.aspx?id=1723&gid=287

dc2x4drvr

With that cam, vacuum for your power brakes could be a problem..

455man

How much would an open spacer help with his 750 and dual plane intake?

cutlassefi

14hp, see my dyno test.

Scott Hamel

just add a vacuum canister for my brakes

Scott Hamel

i'd like to open it up with a spacer but with a RPM intake carb and spacer with air cleaner not sure if i'd clear the hood?

DeltaPace77

Keep in mind, a vacuum canister doesn't make any vacuum, just stores the most vacuum the engine makes for awhile. If the engine itself never makes a strong vacuum at any point, all you're gonna get. As mentioned, if you contact the cam manufactures tech line, then can give you a part number, for a slightly varied grind of the cam you're wanting. Good giving them a call anyway, as can help with the cam selection, for your set up.

ah64pilot

Those cams are about the max for power brakes but you shouldn't have much problem. With a canister I think you'll be fine. Any more cam and you're gonna need to start looking for alternative vacuum sources or go to manual brakes. I prefer the latter, I did it on the silver can and I love it!

cutlassefi

With the cam I recommended you'd be fine for power brakes and a 2200 or so converter. I've sold three or four of these for various big blocks in the last 6 months, no issues with power brakes and low stall converters.