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71 Chevelle SS clone - 8.1L Swap

First off, if Russ posted what he paid, he would have done so in CDN currency. The difference isn't chump change. Secondly, in Alberta you are not gonna find this car, or one that looks like it for $12K. A rolling shell without drivetrain, interior etc will usually sell for $6-$7K easy here.

Buying one from the US is not impossible, bit it isn't free from extra costs, time, and transport, plus customs BS. A $12K US car would end up right around $25K CDN, and that is if it has no trouble getting through the "Out of province" inspection.

I know Russel has been searching for one of these for the better part of 2 years now. I also know Russel wouldn't dismiss any option without doing all the research either. He has a passport, a good tow rig and a great trailer...if that option was best he would have taken it.
 
I'd love to do a burnout in this car, but it'll just stall if I try lol no low end torque at all...

As far as the price paid - I don't think I posted it, but I paid about 10k less than local market value. The US cars always wind up more expensive once you factor in getting it here and getting it registered. Those out of province inspections are not easy to pass and are designed to fail any vehicle more than 5 years old. A 50 year old car they'll find plenty wrong with

This car may be full of bondo I could not find, but by the time it rears its ugly head I hope I have the time to redo it right by myself.
 
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Just my opinion, but I would sell the 8.1 to one of the fanboys and just do a modern Efi Conversion to the current bigblock in the car you will be grief and money ahead .

Of course the diesel guy in me says Dmax swap!
 
598 cid standard deck shortblock from Blueprint...

https://blueprintengines.com/produc...e-engine-big-block-gm-style-shortblock-ps5980

Saw Dave Frieburger and Steve Dulcich put one together on engine masters. Dave convinced Blueprint to build and sell these. The idea being because it's a low deck a guy could buy this short block and all his 454 stuff, like heads, intake, headers etc etc would all bolt on. Cheap way to get a big inch stroker into your car. On the dyno with cheap stock late model heads (like you'd find on an 8.1) with a dual plane intake, 850 carb, XE272 flat tappet cam it made 714 ft/lbs at 3500, and peak hp was 545 hp at a leisurely 4700 rpm. Short block even comes with a warranty.

Of course they also dressed it out with some Brodix parts and a huge dominator to show the other extreme. Even with only 10:1 CR it made 774 tq at 5200 and 853 hp at a perfectly sane 6300 rpm. 1250 cfm Dominator...lol

Anyways, $5600 for that short block is a crazy good deal IMO.
 
Wow, this thread is all over the place.
I'm going to interject my 2 cents here. I
understand it's easy to get all excited with a new car and have dreams of engine swapping. But it seems that you didn't do any justice to your current engine.
It seems that you just ran out and got an 8.1. which I respectfully disagree that belongs in a car like this. It lacks real aftermarket support and you will be limited to a certain level of horsepower. And no one wants that. A traditional big block like you have in the car now with a stroker crank and aftermarket EFI is the way to go. IMO.

Anyway back to your engine. Your complaining about it running not well and it being down on power.
While I am aware that you might have done some things you didn't mention on the internet. The first few things after you got it home to check the health would be.
1. Compression check
2. Vacuum check.
3. Timing check.
With those wrapped up and if everything checked out. I would change oil, oil filter, change spark plugs, change wires, cap, rotor, fuel filter, fresh gas, etc,etc.
Then I would buy ( assuming you don't have one) a wideband o2 sensor and a carb tuning kit.

Spend an afternoon or a few hours. And I would put my paycheck on that fact you can make that fat block roar again. If the compression doesn't check out, I would cut open the oil filter and inspect it. (Might be worth doing anyway) and then perform a leakdown test to see if it's the rings or valves.

Unfortunately, imo you jumped the gun on the 8.1 and it was shot. Seems to me, since thats not any good, your pissing money away for a short block.
Will the location of the TB even clear the hood on that 8.1?

Lastly an basic aftermarket TBI EFI will allow you to use the cowl flapper as God intended and may be the best part of the whole car.

Sorry my opinion is a bit harsh, and I'm not trying to shit on your build thread. But it does appear you lack a real direction. It's a sweet car. Welcome to the chevelle club. And sorry @Bowtie85, my chevelle is packed away for the winter. No "brake burns"

-Beags
 
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I started tearing the 8.1L down last night and found a bunch of glitter deposited in the lifter valley. I'm guessing I am going to find bigger issues once I pull the bottom end apart later this week. Depending on what I find, I may have to abandon ship on this particular engine.

Looking at the Holley Sniper EFI setup, I'll be close to $3000cnd in for the EFI setup, electronic ignition and fuel system. I do like the looks of that setup, but I may still have mechanical issues with the 454 that would need to be addressed as well. I may need to change the intake and camshaft to better match the power band I want for the vehicle, plus I would also need to put a new belt drive setup on it as the existing setup is definitely not right (both belts are operating at angles, and not the same angle either). I can't just go get a setup from the junkyard as there is nothing with a BBC out there, so I'd have to buy something online. That easily puts me at $4000+ to bring the 454 up to snuff. Yes, I'll need to add the fuel system for the 8.1L as well as a flywheel, but it more or less bolts in otherwise. The electrical stuff will not have any cost right now, as I have everything I need on hand already. I feel like I can definitely swing the 8.1L for a fair bit less money even if I have to buy a second long block.

My other concern with the 454 is that I really don't know anything about the engine. For all I know, it's a mid 80s low compression smogger engine that makes under 200hp. I know for sure that it isn't original or numbers matching. Based on how it drives, I'd definitely say it makes a lot less power than a stock 71 Chevelle 454 would have. I understand the dislike of the 8.1L. I understand the dislike of people who want the classics kept original. But this is not an original car, and I just don't think that an aftermarket EFI setup is going to be a magic cure-all for this application. 320hp/440ft lbs is plenty enough for me. I want to keep the car a BBC, otherwise I'd just drop a Gen 4 6.2L LS in for an easy 425hp.
 
Russ, I'd start with pulling the valve covers and seeing what heads are on that 454. That costs nothing and will narrow things down at least a little. If it has 781's at least it probably just needs to be unfucked. If it has peanut port heads then it very well could be some smogger pull-out.

Secondly, and I know this might be heresy to you...but have you considered staying carb'd with a good carb? Spend the money elsewhere. Carb's still make more power, and you already have one.
 
The 454 in Ratbag is nothing special...it would be funnernhell in a chevelle.
Just agreeing with the other guys about spending a few hours on what’s it it.
I’m all for the 8.1 as well.
 
All these guys wanna bolt on efi and give er. That’s fine and all, but hell I’ll take the 20mpg my carb’d roller cam small block all day er day. Nothing wrong with a well tuned vacc secondary carb.

Sounds like a lot of work to swap in that 8.1 vs unflocking that 454 Just like said above eh. A stock fuelly truck motor with no overdrive is just gonna drink fuel unless your gonna drive down the highway doing 45mph.

And to those that say peanut ports are junk, good thing they flow about as well as a vortec sbc head. While yes they aren’t the first choice, they aren’t as bad as made out to be. I’ve seen that smogger of @max 02 ’s get sent into the danger zone and seems to make not bad power fwiw.
 
Your car, your dream. It's seams you have picked a course and are going to do what you have to stay that course regardless if it doesn't make sense to the rest of us.
Might be worth noting that a 8.1 might not make the power where you want it for a car application.
I am all for a 8.1 just a stroker kind and not for a truck engine.

So what if it's a smogger engine? A cam swap and some nice low end heads would be cheaper then a shortblock.
It's insane to me that you would spend time messing with a blown up 8.1 instead of just running the numbers.
What happens if it's a 427 or something desirable and it just needs ( as Rene says) unFucked?

I also find it odd you will say, oh I'll just order a shortblock. And then complain about the cost of an efi kit. Got to pay to play.
Oh well, I'll butt out now. Happy chevelling.
 
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Take the accessories off the 8.1 and bolt them up to the 454. Why spend big money on aftermarket brackets and pulleys if you don't have to.
 
Chevy305 said:
Take the accessories off the 8.1 and bolt them up to the 454. Why spend big money on aftermarket brackets and pulleys if you don't have to.
Click to expand...
Serpentine belt system is so ugly! If your gonna keep the stock look don’t do it. Spend the time finding the proper V belt brackets. Put a 8.1 in it then it’s all fair game.
 
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All the 454's I had were 1973 and 1974 vintage ,low compression with peanut port heads,but I never had the feeling they were low on HP or torque despite their rating being only 235 HP and 360 ft/lbs torque..
Just swapping a cam in one that had a few dead lobes and a 450 CFM Holley carb woke that thing right up,it would spin 36" tires with a TH350 in my '77 K2500 very easily,and scratch 20 feet going into second gear..

The Chevelle station wagon I had with a '73 454 from a bone stock Caprice ran much stronger with a Holley spread bore Q-jet replacement carb than it did with the oem Q-jet carb..
Adding a Mr.Gasket distributor advance curve & weights kit and fiddling with various springs also made a very noticeable improvement..

I feel peanut port heads are better for all around street use,they keep the velocity going faster and make more low end power and torque ,and that is where you need it most on the street--and they will still be adequate for some strip runs too..
454's are long stroke engines and winding them up too high in stock form usually results in a tossed rod,I never wound mine up much over 4500 rpms..no need too,when the rear tires are already roasting..

I don't know if the 8.1 fuel injection would be compatible with an older 454,if it could,that might be an option..
But--I say there is nothing that sounds more awesome than a big 4 barrel gulping down a few thousand CFM's of air when you boot it!..
 
To be clear, I'm not planning on just yanking the 454 out without learning as much about it as I can. Gotta know what it is if I want to sell it, after all.

That said, this 8.1l ain't gonna happen. The further I dig into it, the more issues I am finding with it. It definitely has a ton of shavings inside. I got it on the stand last night and drained the oil. There was about a cup of silver oil inside of it. I'm more tearing it apart out of curiosity than a desire to rebuild it now. I'll put it back together and re-list it for someone else to pick it up for parts.

I am still undecided what route I am going to take with the engine be it bring the 454 up to snuff or find another 8.1L to put in the car. I definitely plan to ditch the carburetor and mechanical timing control either way.

I may have some time tomorrow night to bring the car inside and try to figure out what it has for an engine.
 
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