Before Black BS'ing thread.

I decide to sell my spare 3800 stall speed ( stalls at 3400 on my 274) JW Turbo 350 converter and get a 3500 JW. Summit has it for 483.00. Jeg's had it for 362.22 shipped. That's cheaper than re-stalling the one I have, considering the shipping both ways to JW. The one in my truck now is a 2800 TCS billet converter that works much better with the nitrous than the 3800 did. The 3500 should stall at 3100. The tighter 2800 converter was worth 3/10ths. in the 1/8th over the 3800. Less wheel spin for my MT Street Radials.
 
Fast Lane Friday on the 1/8th mile pit road strip. N/A with a 125 shot of N20. After the Corvette, a 392 Hemi Charger went down to the truck.


 
Nope. It's a 74 Toyota I have had since new. It's had various Buick V6's since 1977 and it has 360,000 miles on it.
 
I had a spare 4.1 291 block sitting around that was supposed to be standard bore, but was actually .030 over. It also had small cracks in the deck on the center bolts. I honed it out to 4" and had it decked .005 to see how deep the cracks were. They were deep enough to cause concern. I put Time Sert thread inserts in the 4 bolt holes affected by the cracks. Attached is a photo of the finished inserts. I used steel inserts and used a big flat whetstone to bring them down flat to the deck. I countersunk the holes to within .015 of the full depth the countersink tool goes to. I modified a Time Sert fixture I bought cheap on E Bay to bolt it flat to the deck with a drill bushing to drill the holes straight, then used the tap and tap guide in the 7/16-14 Big Block Chevy kit to tap the holes for the inserts. I will have another .005 taken off the deck if I ever use this block. The biggest problem is getting the inserts in perfectly square to the deck. I first tried this on a junk block and got them crooked before I used the plate type fixture I modified. Having the inserts even with the deck, instead of recessed as the inserts are intended to be, should keep water away from the studs.

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Put an offer in on this. My LC2 setup needs a home. 3.8 car. Pretty nice overall. Lord knows I don't need 3 G bodies but i've been looking for a clean G wagon for 6 years and this popped up. I have enough parts floating around that I can probably get this in the low 12's with what I got for $500.
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Put an offer in on this. My LC2 setup needs a home. 3.8 car. Pretty nice overall. Lord knows I don't need 3 G bodies but i've been looking for a clean G wagon for 6 years and this popped up. I have enough parts floating around that I can probably get this in the low 12's with what I got for $500.
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Then all you need is a wife and kids to go with that!
 
Been a while since anyone has been on this thread. I swapped my 270" iron head flat tappet spare engine into the truck last month so I could go through my 274 with the pain in the ass girdle. I felt a vibration at 2000 RPM that felt a little like when I cracked my main webs. Turns out it had the same vibration with the spare. The only change was a 2 1/4 into 3" stainless exhaust system. 304 stainless has a totally different sound and feel then mild steel and that is the "vibration". I took the 274 down to the bare block to inspect for cracks. It looked as good as the day it was built. I put new cam bearings, mains, and rods and reused the pistons and rings which had perfect 215 psi compression and leak down. The roller cam and chain were perfect. All the rod bearings were good, but had a little wear on one side. (CAT rods are not machined very well) I have Molners in the spare. They are first rate. This 274 engine has GN1 heads. I put the 274 back in Monday and it runs strong. Feels like 75 more horsepower than the 270 and way more torque. I also looked very closely at the Diamond moly top rings. I have been running a 150 shot of nitrous, which is not recommended with moly rings. They looked perfect, but I am going back to 125 since there is no traction at Homestead Speedway's pit road drag strip. A 150 shot on a V6 is like a 200 shot on a V8 as far as per cylinder stress load goes. The girdle is doing it's job well. It just takes way more time to assemble the engine but it is worth it.
 
I had a spare 4.1 291 block sitting around that was supposed to be standard bore, but was actually .030 over. It also had small cracks in the deck on the center bolts. I honed it out to 4" and had it decked .005 to see how deep the cracks were. They were deep enough to cause concern. I put Time Sert thread inserts in the 4 bolt holes affected by the cracks. Attached is a photo of the finished inserts. I used steel inserts and used a big flat whetstone to bring them down flat to the deck. I countersunk the holes to within .015 of the full depth the countersink tool goes to. I modified a Time Sert fixture I bought cheap on E Bay to bolt it flat to the deck with a drill bushing to drill the holes straight, then used the tap and tap guide in the 7/16-14 Big Block Chevy kit to tap the holes for the inserts. I will have another .005 taken off the deck if I ever use this block. The biggest problem is getting the inserts in perfectly square to the deck. I first tried this on a junk block and got them crooked before I used the plate type fixture I modified. Having the inserts even with the deck, instead of recessed as the inserts are intended to be, should keep water away from the studs.

View attachment 301765

VERY NICE! I have a 484 with a couple cracks, if I sent a deposit and shipping costs could I borrow that fixture sometime?
 
Take a look at this on E Bay. https://www.ebay.com/itm/Kent-Moore...254392&hash=item43d564095c:g:RwcAAOxyBC1SCd8n This is what I used to adapt it to a Buick bolt pattern. Not sure what engine it is for. I had to elongate the holes with a die grinder. It's pretty crude. The large hole is where I put a drill bushing and it's where you put the tap guide. I used a Time Sert 0761D big block Chevy thread repair kit. I used a drill bushing that fits in the large hole with a 7/16 bolt with a sleeve on it. It centers the plate on the bolt hole, then you tighten down the plate to the deck just snug. Next you put a drill bushing in the hole with the ID of the Time Sert drill bit. You drill out the hole and then countersink the hole with the countersink tool being careful to not go too far so water will not get to the stud or bolt. Then the tap guide goes in the hole and the hole is tapped out. The insert is installed with a driver tool lubed with driver fluid and a special locktite that only the Time Sert dealer sells. It goes on the threads. It sets up fast and if you make a mistake you have to heat it to get the insert back out with an easy out. If you can get the Time Sert 0761D kit with mild steel bushings available on E Bay from the Thread Doctor for $125.00, I could send you the plate and drill bushings with bolts. I got the drill bushings from McMaster Carr. Another way to drill the holes straight is to use a magnetic drill that will attach to the block and drill it straight. Those drills are big bucks. That's why I adapted the plate from whatever engine it was made for. The universal block repair kits from Time Sert are $400.00-$500.00.
 
Thank you! This is the "other" 484 I had when I sold you the un cracked 484. You build that block into something? I was always curious reading your posts.
 
So hypothetically, what about a stock cylinder head with a drill bushing instead of the plate? Probably can't fit the drill through it and/or the tap extension. Alternately, I could have my machinist buddy build a proper one out of a thicker plate to make it more idiot proof (which is something I happen to need). Maybe I'll just have him mill the whole top off an iron head for a jig lol.
 
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I tried drilling out the threads using a cylinder head and a long 29/64 drill bit. The head is too loose a fit. The tap can also go in crooked even with the tap guide. You can't hold it straight by hand. A 29/64 ID X .750 OD X 1.380 or so long drill bushing fits in the plate and so does the tap guide. A 7/16x14 bolt with a shoulder lines it up in the center of the hole. A steel or aluminum plate would be the ideal set up, drilled to the V6 bolt pattern. The engine I bought from you is in my truck now. It's the one I just went through.I had it machined for a girdle with no shims used, line honed, square decked, and bored A couple of years ago. It took nine months to get the machine work done. So far it is working great. It replaced the last one that had egg shaped cylinders, cracked deck, and stripped head stud. Something caused that block to distort. That's the one i drilled using a head. Studs were crooked and had to put them in after the heads were on. I gave up on that block and built the one I got from you. I still have the old block. I honed it to 4" and removed the thread inserts and put oversize inserts made for a Chevy. That block would be a last resort to use.
 
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