Nick H.

I have heard the same about the Sniper EFI from someone else I was talking to about this, but they suggested that I may be better off just sticking with the carb, and that my low efficiency is likely caused by a poorly tuned/adjusted carb or ignition. The Sniper setup I bought is still in the box, I haven't started the install yet. I may try to recoup some of my money, it was a pretty expensive setup, but I'd rather "buy once, cry once" as they say. I was planning to go with EFI and electronic ignition, in the hopes that the combination would help reduce detonation more effectively. It's already got an MSD electronic distributor, but that's just a standalone ignition setup that was supposedly "top-of-the-line"... 30 years ago. I'm going to list the Sniper EFI kit for $900obo, see if I get any interest. I paid just under $1,400 shipped in 2021, but it sells for $1,200 now, so I figure 25% off is probably the best I can hope for out of it. I just don't know nearly enough about this kind of thing to really make the best decisions on my own. I can fix just about anything on a car, but engine building is something I've got zero experience with. 😭 I currently have tailpipes that dump shortly after the rear axle. I'd consider extending the tailpipe either out the rear, or out the side just ahead of the rear bumper. The car sounds good, it's just SUPER loud. The stereo (factory single-speaker AM/FM/8-track) is useless with the engine running, and carrying a conversation is impossible. It's likely that I'll pull the interior to install some Dynamat or similar sound deadening material, that should help a bit, but I'm hoping to stop setting off my neighbor's car alarms by driving down the road (with a 3200rpm stall converter, there's no way to "idle" down the road sadly) I'm going to do some more research on EFI setups, and I'll reach out to the manufacturers I've been looking at for heads, and see what they suggest. I'm leaning toward a port EFI system instead of TBI, but if I can get this beast to run on pump gas with the current carb, it's likely I'll just go that route. Old pics are in the linked thread above, the car hasn't really changed much since then, unfortunately. I'll be grabbing more pics along the way though, and I'll be sure to share them here!

I posted here 11 years ago looking for advice on my dad's '70 MC, trying to make it more street-friendly. Problem was, I was 25 at the time, and simply didn't have the income to support the changes that I needed to make. So the car sat. And sat. And sat some more. It was garaged the whole time, and I've started it up every once in a while to keep things from seizing up, but it still needs some work before I'd consider it road-worthy. I have made progress in my career, and I have the income to finally get moving on the car. I started buying parts a few years back, and I'm hoping to get the car on the road this summer if possible, just wanted to run my plan by the folks here for a sanity check. First, details of the engine as it sits: 468 BBC 4 bolt main 12.5:1 static CR (Dad said it had "12.5:1 pistons", still don't know what that's supposed to mean) Closed-chamber iron heads - some machining done @ rebuild time, but I have no details. Holley 850DP Carb w/ no choke Offenhauser intake Hooker shorty headers 3" dual exhaust w/ h-pipe Crane CC-314-2 cam (cam card details below): Lift: Intake @ Cam: .3334 @ Valve: 567 Lift: Exhaust @ Cam: .3468 @ Valve: 590 Rocker Arm Ratio: 1.70 Advertised Duration @ .0136 Tappet Lift: Intake: 314 Exhaust: 324 TH350 trans, professionally rebuilt w/ shift kit 3200rpm stall converter (I think? Not entirely sure, my memory is fuzzy) The plan: Replace heads w/ open chamber aluminum heads (still looking for these) EFI retrofit - Holley Sniper EFI kit w/ Sniper EFI fuel tank (Already have the EFI kit, ordering the tank/pump soon) Electronic ignition (Holley Sniper 2? Hoping that this will further mitigate detonation, but not set on the specific model, as I haven't ordered this yet) Replace headers - Current shorties are shot, rust holes on primaries. Already have a set of Hooker stainless long tubes. New mufflers - Current 3" duals w/ fake flowmasters is loud enough to set off car alarms from 20 yards, I'd like to be able to hold a conversation while driving. I know, I'm being demanding. Serpentine belt retrofit - Not really for any performance purpose, just would prefer to only worry about 1 belt, and the v-belts tend to squeal on cold starts, from what I recall. My goal: Get the car to a place where it can run on pump gas. I was told years ago by the mechanic that did the cam break-in that this engine requires minimum 105 octane leaded, currently run 110 Turbo Blue race gas (not street legal. This car is the opposite of inconspicuous - Bright yellow, 4" cowl induction hood, and an exhaust note that wakes the dead. I'm going to start turning wrenches soon. Hoping that this plan will be enough to run 93 octane without pinging. Car's been sitting for quite a while, so before I start the car again, I'll be replacing all filters and fluids. It will also need new tires before it sees the street, the BFGoodrich Radial T/A's that are on it are like new, but VERY old. Fronts were replaced in 2010, rears are at least 25 years old. Once the mechanical work is done, the car will be going in for body and paint work, probably next spring, and I'll probably pull the seats and drop them at the upholstery shop for new padding and vinyl (already have that too, thanks Dad) My question is this - The original advice I received in 2013 wasn't entirely consistent. Do you think the plan I've outlined will succeed? Am I missing anything? Any other parts I should replace while I'm under the hood?

Alright, what about the clutch? Will the f-body clutch work? How about the speedometer?

Guys, I'm looking for a little input here. . . I have decided that it's time to cut down my "collection" a bit, and I want to make my Monte a bit more enjoyable to drive. It currently has a built TH350 behind a 468BBC. It's fun to drive, but it is terrible on gas, and I think I would really enjoy banging gears in this car. Now, one of the cars I'll be getting rid of is a '94 Firebird Formula with the LT1/T56. I plan on parting the car out, but I've been told that the T56 will bolt right up to the BBC in the Monte. I have a few questions. As far as I know, I won't need a bellhousing, the input shaft is the same, and everything will line up properly. Will the LT1 flywheel/clutch setup work? Can I use the Firebird tunnel to modify the Monte trans tunnel for the shifter to fit through? Will I need to get Monte specific pedals, or can I use the Firebird pedals/master-slave cylinder setup? Is it possible to use the SS console with a manual transmission, and how far off will the opening be for the shifter after installing the T56, assuming I don't relocate the engine at all? How about making the factory speedometer work with the T56? I'm going to be rebuilding the T56 with stage 2 internals from thegearbox.com, which they say will handle 600-650HP. I will also be installing a clutch that's up to the task. I am fairly certain I'll need a custom driveshaft, which isn't a problem. This is something I had talked to my Dad about before he passed away, and he thought it would be pretty cool to see it done. I'd like to keep the engine as close to the way he built it as possible, but I may need to drop the compression a bit so I can run it on pump gas. . . Any suggestions? I am parting out two LT1 Formulas, one's a 700R4 car, the other a T56 car. Most of the money is going toward paying my Mom the rest of what I owe her for the car, and I'll probably sell the TH350 to help cover the cost of any additional parts needed for the trans swap, such as the driveshaft, trans k-member, clutch, etc. I don't have a specific timeline for this project, although I would like to see the Monte Carlo back on the road within 2 years, and hopefully finished completely at that time, although I'm not going to be upset if things take longer than that. Any help is appreciated, and if anyone here has done this swap, I'd love to pick your brain for a bit about the challenges you faced. Thanks!

Thanks for the information, I will continue looking for a set of aluminum heads then. I didn't know the head composition could cause pinging. . . I'm still rather new to all of this, I've only helped rebuild engines before, when it comes to choosing parts, I've always had to ask for help. Should I go with a hydraulic roller cam instead of the mechanical that's in it? Maybe something a little more mild? Anyone know where I can find a decent deal on a set of long-tube headers? Hopefully something ceramic coated or stainless, as the mild steel headers that went on when the engine was installed have rusted through.

Here's a couple pics and a video: Pic of Dad with the engine back in '96 when he started the tear-down: And here's a link to the YouTube Video of me driving it out of the garage after doing some work in January 2010, getting the car ready to be driven to Dad's funeral.

I like the idea of the gear vendors overdrive, essentially turning the 3 speed TH40 into a six speed with .78 overdrive ratio. . . Hard pill to swallow though, that's almost half what I paid for the car. Worth considering though, and I will look into it.

Well, I went out to fire the car up today, put a new battery and cables in it, and got her to fire up without doing anything but cranking and pumping the gas pedal a few times. Bad news: Passenger side header primary on cylinder 3 (or 2, not sure which side is #1) has a rust hole in it about the size of a dime. Time for new headers. I'll get them ordered after new tires go on, I found some hooker full-length ceramic coated headers for $400 (same as what's on the car, but coated rather than uncoated). Need a new battery tray also, can't find mine. Found a new stamped tray, with hold down, tray support bracket, and bolts for $75. Probably get that ordered too. Also, I mentioned before in another thread that I needed a new left quarter glass, as someone broke mine out. . . Well, I popped open the trunk, and what do you know, there's a full set of factory glass at the bottom of the pile of body trim and moldings! I already had the glass! Heading back home this morning, should have a few days next week or the week after to continue parting out my Firebird, and I'll make some progress on the Monte. Starting to get excited! Also, I had a guy offer me a set of ported oval-port iron heads for $300, he says they have larger valves than stock, and are ready to bolt on. I'm waiting on the specs, but is there any reason why I should shy away from iron heads, aside from the weight?

You should be fine with some stock replacement rotors in that case. Delco rotors w/ hubs are $43.79+shipping on RockAuto.com, and you can find discount codes online to save even more. O'Reilly Auto Parts has "BrakeBest" brand rotors available at $57.99 each w/ hub, so ordering online is going to save you money AND get you a better part. These parts were looked up for a '70 454 Monte Carlo, although I imagine they are the same parts, regardless of drivetrain. Do you have rear disc brakes too? Or are you running stock equipment? One thing to consider, on a street-only car, you won't gain much by going with a drilled and/or slotted rotor. They can actually cause issues if used in a car that only sees the streets. The slotted rotors will increase the wear rate of your brake pads, and while increasing initial "bite" a small amount, you likely won't notice a significant improvement over a stock-style blank rotor. The best way to improve braking performance, IMO, is to research the pros/cons of the different brake pad and rotor options available, and decide what you are willing to compromise with. Is excessive brake dust a concern? Brake noise? If you aren't going to drive the car hard (i.e. racing events), you don't really need anything more than a blank rotor and some decent pads. I run semi-metallic pads and stock rotors in my '94 Formula, and the brake performance has never left me wishing for more. Granted, that's a completely different animal, but regardless, gaining an understanding of how it all works, what pads/rotors offer as benefits (and drawbacks) over one another, and choosing the best fit for your driving style is the best option. Hope that helps. I remember reading a VERY detailed article explaining the braking systems, differences between different types of pads and rotors, and explaining which work best for different types of driving. If I can find the link, I'll post it here for you.

Cam Specs are (posting as shown on cam card) Lift: Intake @ Cam: .3334 @ Valve: 567 Lift: Exhaust @ Cam: .3468 @ Valve: 590 Rocker Arm Ratio: 1.70 Advertised Duration @ .0136 Tappet Lift: Intake: 314 Exhaust: 324 It's a Crane Cams CC-314-2. The card describes the cam as: ROUGH IDLE, MODERATE PERFORMANCE USAGE, GOOD MID-RANGE H.P. I'm not sure what the actual CR is, Dad always referred to the pistons as "12.5:1 Pistons", so I'm sure that is just the static compression ratio. I'm probably going to try to take it to a tuner to have everything dialed in, and find out what kind of fuel was required. I've been told 105 is the lowest I could safely run in the car, but honestly, I really have no idea how accurate that statement was. It may already be able to handle 93 No-Lead, but I won't know unless I pay someone to figure the engine out. I'll post the head casting #'s when I go home a week from Tuesday. I'll likely be tossing another $50 worth of Turbo Blue in it just to get it moving around the driveway again, get the shift linkage adjusted, and start reassembling the engine compartment.

That's what I thought it was. I'll get that taken care of when I go home. Is there any place where I can order a replacement parking brake cable? The brakes in this car need work regardless, but the rear drums I don't believe have been touched. I'll likely wind up replacing with discs at some point, but that's not a priority at the moment.

Just trying to figure out what I need to do to fix this. Car has a TH400 (maybe a TH350, not sure at the moment), and when it's parked, simply putting the trans in "Park" won't keep the car from rolling. Any incline/decline at all will overcome the parking gear, and the car will roll, and the trans makes a "clicking" noise, almost like a ratchet. I'm guessing it's either an adjustment issue in the trans shifter cable that isn't putting the car all the way into park, or there is something wrong with the trans itself, but you all would know better than I would. Trans was rebuilt, has a shift kit, and works flawlessly in all gears and reverse. Car was originally a column shifter/bench seat car, was swapped for buckets and a console w/ horseshoe shifter before the trans rebuild. Never had issues before the trans rebuild, but I was in High School when the trans was re-installed, and I don't recall exactly what Dad did to adjust the shift cable or anything else when we did it. All I know, I want to take the brick out of the back seat, so I need to be able to make the car stay where I park it, whether that's through repairing the park issue in the trans, or repairing the parking brake. Any ideas? I'll be home in 2 weeks, planning on getting the battery cables re-installed, putting the inner fender wells back in, getting it started up, and doing some thorough cleaning. Still working on a plan for the project, but those are the first things I'm going to do. If there's anything I need to check when I have access to the car, I'd like to know what/where to look while I'm there. I'm only going to be able to work on it 6 days a month until I get a place with a garage.

I'm going to look through my records and see if the head specs are in there. I'll also grab the cam card, and see if I can find out what pistons are in it. I was trying to figure out the final CR last night, and I just don't have enough of the information to figure it out. Are the casting numbers under the valve covers? Or are they elsewhere on the heads? I just want to know if I need to pull the covers to figure out what they are. Originally Posted By: ripleydale Hey Nick, I was under the impression you didn't want to sell the motor, so if it would just be sitting and doing nothing, I thought it might be better to rebuild it. I think you could make a nice motor and replace your torque converter for $3500, and you could sell some of the parts you pull from the motor. Open chamber heads will drop the compression and solve some of your gas problems. If you do it, make sure you check the piston to head clearance. I remember doing that to a 396 once upon a time and the dome of the piston was just catching an edge of the combustion chamber. I have a feeling that band aids like a head swap aren't going to make you happy. That engine and drive train were designed for racing, not cruising or gas milage. I agree, which is why mileage isn't my primary concern. Well, it is, and it isn't. I want better gas mileage, but only because it costs me so much to drive the car. If I could get around 10-12mpg on 93 octane, I'd be happy. As the car sits, it costs FAR too much to drive. After running the numbers, it comes out to $3.83/mile just in fuel costs alone, assuming the current price of $6.99/gallon for 110 Leaded fuel, and the cost to drive 50 miles each way in my daily to purchase fuel. Add to that the fact that a FULL 19 gallon tank of fuel in the Monte Carlo will only get me 38 miles during city driving, and it's a ridiculously impractical car. At 10mpg on 93 octane no-lead, which is currently $3.89/gallon, it would only cost me $73.91 to fill the tank, and I'd have a range of 190 miles/tank. It's a no-brainer. Not to mention, from what I've read, open-chamber heads are MUCH more free-flowing than the closed chambers that are on the car. My only objective is to make the car run on pump gas, any increase in fuel economy is merely a bonus. At 2MPG, I'll still drive it to shows, cruise around town when I'm at home, and enjoy the car, but at 10mpg, I'll do the same, further away from the garage. haha And I will admit, I have a lead foot. It's not just going to be "cruising" all the time, I'll take it to the strip to see what she can do, go on "spirited" drives, etc., but by and large, I simply want to be able to enjoy the car.

Before I sink money into heads, I just want to make sure they will solve the fuel issue, as I would hate to spend the time/money on them, only to find out that I'm still in race gas territory, and it won't run on pump gas. Dropping the compression like that, would I need to replace the carb as well? It has a Holley 750 double pump carb on it now, would that be too much after dropping the compression to 10.5:1? It would need re-jetted obviously, but would it be too much carb for the engine at that point?

Thanks, I'll look into it. Any idea what it would cost? I'm guessing I'm probably around 600-700hp right now, but the car has GOBS of torque, and I really don't want to try launching just to hear the trans grenade on me. The TH400 was built to handle the power, but 3 gears isn't doing it for me, as far as gas mileage is concerned. Once I drop compression and get everything set up right, I think I should still be around 500hp, and still have gobs of torque, but at this point, keeping the BBC in place is going to limit my budget, as the cost of the parts was going to be determined by what I was able to sell the whole drivetrain for. Any ideas on the compression issue? Can a set of open chamber heads and some thicker head gaskets really drop the compression by 2 points? Seems like a bit more than you'd expect, but I guess the open chamber heads really are that much different. Just want to make sure before I spend the money, you know?