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First time poster, did not see anything regarding rebuilding the 4200 LL8 engine. . . Please don't flame me if I missed something!

Anyhoo, I found this 4200. Looks like it would need some serious work on the bottom end, but for less than $200, I find myself very tempted.

Anyone done any rebuilding on these critters? Is it worth rebuilding?

I'm considering the swap into my '68 Camaro. Why? Because no one else seems to be doing it. And I can keep the cute "250" badges on the fenders.

Feel free to snatch that thing up, too. If someone here wants it first, fair's fair. I'm still trying to make up my mind.

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Not really worth rebuilding. I have bought 4 in the last 2 years from salvage yards for customers for around $800.00. Just last week i bought a complete 04 wreaked trailblazer for myself $1000.00 bucks, To transplant the 4200 into my 63 chevy p/u. LARRY C.

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IIRC, you do not want that year engine anyways.

The cylinder head, does not flow that good as compared to the newer ones.
2006 or was it 2008 has the better engine/head?

There are a couple of these engines in the early Camaros & Firebirds.
BBC & SBC Camaros are a dime a dozzen.

MBHD


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 Originally Posted By: NOX
First time poster, did not see anything regarding rebuilding the 4200 LL8 engine. . . Please don't flame me if I missed something!

Anyhoo, I found this 4200. Looks like it would need some serious work on the bottom end, but for less than $200, I find myself very tempted.

Feel free to snatch that thing up, too. If someone here wants it first, fair's fair. I'm still trying to make up my mind.



Offer him $50 and use it as fitment core, a good running 2005 4200 can be had for $500. No one is going to pay $180 for it.

Once your done with the core haul the head off and port it - its worth 20-25HP and swap it onto the other engine. Sell the block/other head to the next guy for a fitment core for $50.

Note the 2002 to 2005 engines had black valve covers and early heads. With a ported early head and good exhaust you'll be close to 300HP.

The late motors have better parts but also cost closer to $1000.


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Sage advice. I will see if he'll take $50.

Been reading many of your posts, EFI. Gotta say, you get a fellow thinking in some pretty cool directions.

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Get a copy of the Aug 2011 car craft....it'll enlighten your day...


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Look up "Self Racing, Durant, OK." They are the 4200 gurus in my book. They have three they built and race. I was impressed when I watched their entry turn in the 8.0's on a 1000 ft strip in a mid size car body. They have some great working knowledge about that engine.
Normbc9

Last edited by Norm Silver; 01/01/12 12:36 AM. Reason: spelling error
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Have that issue. That '68 Firebird is pure inline porn. The only thing that was disappointing was not seeing more of the car, and more of the build. I've been googling tirelessly, and still haven't turned up more than that one under-hood shot.

Norm, that is probably the coolest thing I've seen all weekend!

Last edited by NOX; 01/02/12 07:16 PM.
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Nox,

Talking to the owner Jeff - he plans on attending the convention in May with the car... details on on here. So take a drive it might be worth your while.. :).

And there just might be some other turbo 4200's showing up...

Are you planning on running a stick or auto trans?

I know someone that has a complete T56 setup for a 4200 ready to bolt in. Its just come up for sale. Trans flywheel clutch shifter etc - full meal deal.


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I would really love to see that car in person. I'd really like to see his motor mounts and crossmember setup.

If I end up doing this swap, I'll stick with the 4L60E behind the 4200. I want to retain the stock column shift on the Camaro for the simple fact that you just never see them. Ever. For my purposes, the 4L60E would be more than adequate. I'm really just looking for good highway performance in this car, plus the wierd factor.

Sure would be fun at the car shows, parked next to all the generic and BORING first gen Camaros with the usual crate 350 swaps. Just thinking of all the dirty looks and WTF's gets me all excited. I really like the idea of a small "Vortec" logo right behind the "250" badges on the fenders. Heads would be scratched, I think.

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this is the honest truth ...


Last year I took the truck to the car craft nat. and day 1 we parked beside a 9.999/10 69 camaro with an LS swap.

More people stopped and looked at the 4200 turbo installed in a beat up (body wise..)flat black farm truck than the shiny camaro.

#1 question WTH is that???


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The more I read and the more parts that you develop the more I am leaning toward a 4200 my '68 flatbed rather than the turbo 292. Like you have said all along cheaper in the long run with greater fuel economy and probably more useable power. The 292 can go somewhere else. Maybe the '59 Lark. \:o


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4200 dimension

Note this is NOT the stock oil pan shown!


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Wonder if Inliners will open up their drag racing classes to include the 4200 engine. Right now it only has class divisions for the early Stovebolt/GMC engines and the late 194-292 engines.



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There's an inliner class for any type of inline. I've held drag records with a (relatively late model) 1965 Ford 300 and a 2003 BMW twin turbo 4-valver sedan.


FORD 300 inline six - THE BEST KEPT SECRET IN DRAG RACING!
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I love the 4200. I have one in an 04 TB. I agree, it would be a great addition to an early truck. My way of thinking says, you need all the assosiated wiring and trans for a swap. How would you overcome things like the secondary air system, wheel speed sensors, etc...

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 Originally Posted By: Whitedog
I love the 4200. I have one in an 04 TB. I agree, it would be a great addition to an early truck. My way of thinking says, you need all the assosiated wiring and trans for a swap. How would you overcome things like the secondary air system, wheel speed sensors, etc...


It's helpful to have everything, but not always necessary. I can disable air injection, evap, etc, etc. Wheel speed info is not necessary for swaps. Reflashes for swaps are on limeswap.com

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I'm intrigued. I've been looking online at wrecked TB's and Envoys. 2wd seems a little harder to come by, but the trans is the same as 1/2 LS trucks, so no big deal there. Even an early, stock 4.2 is rated at 260-270hp. I know from my TB, that you can run over 20mpg on the highway. Not too shabby when compared to a small block. My biggest complaint is that the power on my 4.2 comes in a little late(around 4000rpm) I wonder what uncorking the exhaust and stepping up the timing would do. It might just make an old truck run like a scalded dog.

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Have a look at the power curves below. The torque curve is actually remarkably flat owing to the VVT. The lag in power may actually be torque management - which can be tuned out.



I have a manual trans in my supra, so torque management is completely off. I find the motor to be more torque-y than peaky.

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Torque management? I didn't know there was any such a thing. Just driving around town, the TB is a little doggy-dog, but once you get on the pedal or put a trailer behind it, it is a whole differnt animal. I assumed it had to do with the vvt of the cams. Torque management does make sense. The 700r4 and 4L60 were known to be jerky, especially in the lower gears. I'm assuming the torque management helps soften things up a little bit.

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 Originally Posted By: Whitedog
Torque management?..... I'm assuming the torque management helps soften things up a little bit.


Yes, but it's also a form of stability control (especially if it's slick) harder to skid at those speeds with less torque available.

I'd rather have the torque and be responsible for "driving" (as opposed to the practice of sheep herding I see so many people do with their vehicles nowdays ).


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My original plans for my 'bolt were to find a 261, or dual carb and split the exhaust on my '59 235. The more I think about it, the 4200 is probably the way to go and I would be much more satisfied with the end result. Finding a wrecked TB and stripping the drivetrain may even be cheaper than rebuilding a 50+ year old drivetrain and trying to squeeze a few extra ponies out of it.

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 Originally Posted By: Whitedog
My original plans for my 'bolt were to find a 261, or dual carb and split the exhaust on my '59 235. The more I think about it, the 4200 is probably the way to go and I would be much more satisfied with the end result. Finding a wrecked TB and stripping the drivetrain may even be cheaper than rebuilding a 50+ year old drivetrain and trying to squeeze a few extra ponies out of it.


Oh, I definitely agree that the 4200 is the better value proposition. I got my 2006 -complete with all accessories, pcm, and wiring- for $850.

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 Originally Posted By: limequat
 Originally Posted By: Whitedog
My original plans for my 'bolt were to find a 261, or dual carb and split the exhaust on my '59 235. The more I think about it, the 4200 is probably the way to go and I would be much more satisfied with the end result. Finding a wrecked TB and stripping the drivetrain may even be cheaper than rebuilding a 50+ year old drivetrain and trying to squeeze a few extra ponies out of it.


Oh, I definitely agree that the 4200 is the better value proposition. I got my 2006 -complete with all accessories, pcm, and wiring- for $850.


X2 - with a good tune, and a decent exhaust your not far off 300HP crank.

In my '51 I stated with a well built 292, - made about 200HP, but drank gas like no tomorrow. Changed to a bone stock '05 4200 motor and picked up 10 MPG highway. No other changes to the truck.


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For the price of a rebuild kit on a Stovebolt, a whole running vehicle can be purchased. Rebuilding the 4.2 can be pricey, but there shouldn't be any need to. I have yet to hear of any TB's or Envoys that have had a major mechanical failure. In fact I've seen many online that are well on there way to over 200k miles.

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But if you add the cost of reflashing the ECM, oil pan , mounts etc., the cost starts to climb quick. We pulled one from an Envoy along with every wire connection and line and layed it out on the shop floor. We were overwhelmed with the complexity and wound up trading it all off. I can see it as a viable swap in the future as parts availability grows and prices come down. IMHO


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If keeping the driveline stock, there shouldn't be any major costs. Fabrication is another story though. The Achilles heal of the whole project is the oil pan. I have a 54 truck. The engine could be mounted higher in the engine bay to compensate for the oil pan clearance issues, but then there is the issue of trimming the fire wall and building a partial tunnel. If I had a MII suspension it might not be such a big issue.

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 Originally Posted By: Whitedog
The Achilles heal of the whole project is the oil pan. I have a 54 truck.


What wrong with the oil pan.



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It's a front sump pan. A quick look into my engine bay, places it right above the solid front axle.

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EFI-DIY has an engine swap oil pan available. Its rear sump.
Search "4200 rear sump pan".



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HERE is how one of my friends installed a 4.2. These pictures span a year, silver wheels to red wheels. Major mods on front crossmember. EFI's pan was not around then. He used the 4.2s trans, ignition and EFI. Much stock wiring was used but I think he had someone work on the ECM. He really likes it and is thinking about doing another one.

Last edited by Beater of the Pack; 01/20/12 09:55 PM.

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Beater- I must commend your friend on his efforts. The duct tape holding the air cleaner on should add another 10 horsepower, right? LOL

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EFI-DIY; What is the cost on an oil pan like that?

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 Originally Posted By: Whitedog
Beater- I must commend your friend on his efforts. The duct tape holding the air cleaner on should add another 10 horsepower, right? LOL


In those first shots he had barely got it going and drove it from his house to the show it had no air cleaner. He fought several issues the next year and duct tape was the least of them. In our area he was in the pioneer mode. He is not an internet guy, he is a hot rodder. I copied much of efi-diy's posts for him and he had some sources of his own. It will be at the Convention/Rappin' this year. Come and see it. I think there will be several 4.2s in attendance. One of my sons gave me duct tape with flames for Christmas. I may let Danny use some. \:D


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I think it's cool he stuffed the 4.2 in an early truck, he could've done what millions of others have done and go with a boring 350/350. I didn't mean any malice with the duct tape. I know as well as anybody that hot rodders have to deal with what they got until a solution is found. Heck, my cousin drove a Ford Ranger around for a couple years with a Briggs and Stratton air cleaner taped to the throttle body.

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 Originally Posted By: Whitedog
I think it's cool he stuffed the 4.2 in an early truck, he could've done what millions of others have done and go with a boring 350/350. I didn't mean any malice with the duct tape. I know as well as anybody that hot rodders have to deal with what they got until a solution is found. Heck, my cousin drove a Ford Ranger around for a couple years with a Briggs and Stratton air cleaner taped to the throttle body.


That -in fact- is pretty epic.

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Epic? An old Chevy with a 4.2 or a Ranger with Briggs air cleaner.


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 Originally Posted By: Beater of the Pack
Epic? An old Chevy with a 4.2 or a Ranger with Briggs air cleaner.


Both!




But in different ways \:\)

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I keep doing and re-doing the math, building up the 250 vs. swapping in the 4.2, and every time the numbers come up in favor of the 4.2.

Oil pan doesn't bother me. Limequat's Supra build illustrates that well enough. Doesn't seem like that big of a deal.

Wiring harness could be ugly, but again referencing Limequat's build, doesn't seem that horrible. Certainly not bad enough to make a fella throw in the towel.

I have my eyes out for a local donor. They must be pretty popular, or in low supply around here, because the ones that end up in the junkyard are stripped bare in a matter of days. When I say stripped bare, I mean down to the body shell. These people aren't leaving a scrap. I've never even got a sniff at a motor, yet.

Thanks for the link to those pics, Beater. Would be cool if we could get some shots of the frame/crossmember mods and engine mounts. That's what I'd really like to see on that turbo firebird build.

Found a fair looking LT1 in the classifieds. Was tempted for about 0.6 seconds. Too easy. 350 Camaros are more common than dog exhaust.

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