lilgiff

I built this motor about 10 years ago. Afterwards the car sat moth balled for the majority of the time, save for a few hot runs around the block. Bottom line, the motor was never dialed in and fine tuned. I wanted to get some opinions on the build and see what you folks think I should be getting from the powerplant (HP & Torque), possible guidance on what would wake it up even more, and what gear you think I should run. I really love the torque these Olds motors make and have read plenty about how they really take advantage of mid-range ratios like the 3.42. I think this car would run respectably with a 3.73, but welcome everyone's feedback!

Engine:
Block: Oldsmobile 350 CID (OE)
Carburetor: Holley 4150 HP Pro Series 830 CFM
Intake: Edelbrock 7111 Performer RPM
Fuel Pump: Mondello High Volume Mechanical
Rod Bolts: ARP
Pistons: TRW 2320 (.030) Forged Aluminum
Rings: Moly
Bearings: Michigan 77 (Main, Con Rod, and Cam)
Timing Chain: Mondello TR-252 Double Roller
Lifters: Mondello Hydraulic HL-230
Camshaft: Mondello JM-20-22
Lift - Intake: .496 Exhaust: .512
Adv Duration - Intake: 266 deg Exhaust: 274 deg
@ .050 - Intake: 226 deg Exhaust: 230 deg
Oil Pump: Melling HV, Pickup & Hardened Drive Shaft
Oil Restrictors: Mondello
Oil Pan: Milodon Deep Sump 7 Qt.
Water Pump: Mondello Aluminum 5 9/16”
Other: ARP & Stainless Grade 5 Fasteners
Machine Work: Line Bore .030, Recondition Rods .010, Turn Crankshaft .010, Brass Freeze Plugs, Install Cam Bearings, Balance Rotating Assy
Exhaust:
Headers:
Modifications: Custom Powder Coating by Jet Hot

Cylinder Heads: Oldsmobile #6 Casting (OEM)
Modifications:
Rocker Arms: Mondello ARK-350 Aluminum Roller
Valve Covers: Mondello Tall Cast Aluminum
Valves: Mondello Stainless Steel Posi-Flow Swirl Polished
Intake: 2.00” Exhaust: 1.625”
Springs: Mondello SK-245-D Double Coil
Machine Work: 3 Angle Valve Job, Guides, Locks, Short Hardened Seats
Stage 2 port & polish by the Rocket Ranch

Model: Turbo-Hydromatic 350 (OE)
Modifications: TCI Pro Super Rebuild Kit
Converter: B&M Holeshot 2400

Model: BOP GM 10 Bolt (OE)
Axle Ratio: 2.56:1

lilgiff

Pictures
This was a loooong time ago.. I have since added a pro billet distributor with a 6AL and a nice TCI balancer.

ah64pilot

Definitely needs gear...

I had the identical cam in a 455 with stock E heads...everything else was the same as yours and the car went 13.001 on street tires (BFG Radial TA's) It ought to be a strong performer but needs more gear with that cam. I would start with the rear end.

lilgiff

Obvoiusly!
Any thoughts on ratio? Think 3.73 is too tall? Don't want to lose that famous Olds torque when driving it on the street... that takes all the FUN out of it! Haha!

coppercutlass

3.73 is perfect for the street . You can run a 28 in. Tall tire on the street then use a 26 in. Tall one at the track to get roughly a 3.91 gear. This is what I do and I like it. Dunno if its me but 830 seems a bit big to me. Jmo but you said you drove it so I assume it is running well.

ah64pilot

X2...you have the same carburetor I have...Holley HP 950 flowing 830 cfm. Mine has been worked over quite a bit but it still flows 830. But, if it's working for you...

cutlassefi

I agree with the rest, too much carb or not enough cam. What's the compression? Could probably use a 2800 converter as well.
And I don't understand the "line bore .030, and recon rods .010", can you explain?

Thanks.

ah64pilot

Care to enlighten anyone on how much power your SMALL BLOCK made? Hahaha!!! You creep!

You don't have to say, but I'll give a hint...most big block owners are looking for that number

lilgiff

C/R is estimated 9.5 to 1. Agreed, I don't like the 2400 stall converter that's in it now... kicks in a little early.

Block is bored .030 over, reconditioned connecting rods .010

380 Racer

Both my 355 and my 380 loved the 950 HP I've seen them used on anything from a 283 to 468s. I feel it's the right carb IMO. Yes a higher stall is needed 2800-3200, again IMO.

coppercutlass

Yeah but u are comapring apples to tortillas here. You have a 9 second car . Not to mention you probably have big runners high flowing heads high compression and a big cam to support it all. I'm guessing a 950 hp will have to be seriouls tuned for an sb set up. Most carb literature I have says if you have to go up or down more than 2 jet sizes its too big or small.

380 Racer

I'm afraid you assume too much. The 950 was never run on my 9 second 425. I used it on my last version 355 which ran high to mid 11s, 10.5 compression, very mild home ported heads, hyd Engle (Mondildo) cam. Sorry don't remember cam numbers. Performer RPM intake and box stock 950 carb.

The same carb (with minor jet changes) on my 380, plus more head porting, a Street Dominator and a solid cam ran 10.70s. I'd say that is a good all around carb. Why do you think I just dropped a buttload of money and went racing? I started racing my car in 1984, it ran a 14.10.

380 Racer

Timeslip.jpg

captjim

.009 over the dial in and a .005 light?? You suck!!!

coppercutlass

I'm not assuming. I tried a 750 eddy and it was way big. An out the box 650 quick fuel was way too big from my experience atleast. So yes I'm sure if I put a 950 I would assume a 950 would be to big based on my experience. I'm not doubting it worked for you but your 11 second car may have been more strip than street at that poitn. How loose was your converter ? What's gear ? I know looser converters allow bigger carbs. It all varries. Btw an out the box 650 holley dp for me has worked the best. Need to change pump cam but it has worked better than any other carb I have had .

380 Racer

IIRC it was about a 3000 stall, 4.56 gears. I was shifting @ 6200, a 750 dp was good but the 950 was better. The point I was trying to make was that I worked and worked my combos till I couldn't get any more out of them.
From what you posted Mr Copper......you assumed alot.

Hey Jim......too bad they all aren't that good......LOL.

jag1886

I would think for now a smaller carb would help him, he's not running a 3000 stall or a 4:56 rear end. He can always use his big carb later if he gets that carried away with the car.
I'd only change the carb and the gear and unless you like really bad gas mileage an OD transmission, put in an OD and you can use more gear and get fair-good mileage.
Maybe mileage doesn't matter you didn't say.

lilgiff

No, I definately don't care about mileage for this car. ET and blowing the tires off on the street... Those are my goals Oh, and embarrasing mustangs, of course.

ah64pilot

How are you seeing a .005 light? I see a .505.

Can you explain the Sportsman R/T system to me? I have a consistent .530 R/T and want to work on it to get as close to .000 as possible...is that possible on a sportsman tree?

***Nevermind...my local track shows a .500 light as a .000...that is why I was confused by what you were talking about. I left my question intact so that you could see that for a min, I was an idiot

I'll keep working on my reaction time...although this is the first car I've had that I could actually bother working on a R/T with***

380 Racer

Back before they went to LED bulbs on the tree, a perfect light was a .500. So my light was the same as a .005.

PS. Look at the date.........1998.

coppercutlass

i heard it was much easier to anticipate the old lights compared to the led's that are much quicker.

ah64pilot

Roger, just caught that...thank you!

A couple of years ago a younger friend of mine thought I was crazy when I said a perfect light was .500. He kept telling me I could go .000 but the last time I had ran a car down a track was 1998 when I graduated high school. Now it all makes sense.

gearheads78

Never raced at any track with LEDs. Are they hard to get used to?

ah64pilot

To be honest, it wasn't until 380 made that comment that I realized that Houston Raceway Park is using LED's. I never noticed the difference other than that the reaction time on the slip can read less than .500 down to .000. Before, less than .500 was a red light. Then again, there was about a 10 year lapse between track days

I don't have any problem with it now. Doesn't Texas Motorplex use LED's?

gearheads78

I am sure that do but I have not been there in years. Last fast car I had ran 1/8 miles tracks around here but that was 3 years ago.

lilgiff

Wow... My thread somehow developed ADHD! Let's bring in the focus here.
Has anyone run the 3.42 and the 3.73 with a fairly hot SBO?

coppercutlass

Yes I have ran both. I ran a 3.42 went to a 3.73 which I'm currently running. The 3.73 works great all around.

lilgiff

What do you have in the rest of your setup? Cam? Valves? C/R? Converter?

coppercutlass

Comp cams 280 h , 10 to 1 compression, 2.072 intake valves, 1.63 ex. 2800-3000 stall converter. Close to 400 hp.ran 13.3 at 103 with a small carb and tight converter.

rktolds

Anybody run this combo with a Muncie? I will run a mild 68 350 in front of an M20 and 3.73's until the funds allow a full blown rebuild.

ah64pilot

I think the best thing you can do for a combo regardless of power is run better gears. I think that'll suit you well and then it'll really wake up when you rebuild it

coppercutlass

3.73 gears are perfect for the street. I mentioned it before you can run a 28. In. Tall tire on the street to keep that 3.73 to 1 ration and run a short sticky tire like a 26 in. To bump it up to a 3.90 to 1. It then comes down to what you wanna do. I know guys running 4.10 gears on the street but it's not the greatest on the highway I'm not sure on a 4 speed rpm wise. I run a th400 . Maybe someone with a little more 4 speed experience will chime in.

Indy_68_S

Standard Muncies (M-20, M-21, M-22) & TH's (350 & 400) all have the same 1:1 top gear ratio....

SBORule

I started racing in 1976, it was 1966 Mustang 2+2 fastback with a 1969 Boss 302 with a toploader 4 speed and a 9 inch rearend with 4.86 gears and with N50 street tires, which were 28" tall about 10" wide, it ran 11.50's @ 119 mph. Not bad for my first car. But then again it was an ex-AFX drag car all it's life.

In 1984 I had a 1980 Turbocharged V6 Regal that was street legal and it ran 10.teens over 130mph.

In 1985 I had a 351 Windsor powered 1971 Pinto with a 9 inch rearend that was street legal that ran 10.40's with 150HP shot of NOS. It had a Holley 850 cfm carb built by BoLaws on it.

Those 830cfm carbs will make more HP and TQ than any smaller carb will, even on a mild SBO 355. I ran a Holley 800cfm double pumper on my 355 Olds 20 years ago and I think it ran every bit as good as the BG Mighty Demon 750 that's on my car now.

Only thing you really need to do is put some 3.73 gears in it or 3.55 gears if you want to spray it with some NOS.

SBORule

Oh my, I forgot to mention my 1971 Nova that had a 427ci BBC, M21 4 speed, 12 bolt with 4.11 gears that ran 10.90s, never used NOS on that car.

My 71 Chevelle SS 454, turbo 400, backhalfed ladderbar 12 bolt 4.56 gears 14x32 GoodYears that ran 10'0's 132mph, never ran NOS on it either.

There's a few more that I won't bore you with but really I think if you want to make you car run quicker, that 20-22 cam should be replaced with a JM 25-28 if you really like those Engle cams. If you want to run NOS get something around 238-242 @ .050" and add 4 degree's on the exhaust lobe with lift in the .550" range with 113-114 lobe seperation. If you don't plan on running NOS, same cam with 110 lobe sep should do the trick. You also need to get rid of that B&M Convertor and buy yourself a 10" 3000-4000 stall with anti-balloon plate from that place in Alabama called PTC their prices aren't bad and they seem to have a good reputation unlike B&M.

Beware of people who send PM messages, they usually hide behind the curtain for a reason.

11971four4two

pure