Fuel Air Spark Technology

The first oil change on a fresh ^engine is always an "aha" moment. When you find the oil clean and the filter perfect you're totally relieved. When you find material in the filter, or on a magnetic drain plug, your heart drops and you question where it came from. Sometimes it is quite easy; other times it's like this couldn't be inside this engine!

We highly doubt you have a ballooned torque converter after 5-10 miles of driving, unless those first few miles were repeated power brake launches. We don't think your little 388 has enough torque to balloon the converter. You've listed the few sources your brass-type shavings in the oil could be from. The wristpin bushings are usually out, because if the bushing locks up, they rarely shed much debris, and the pin continues to rotate in the piston. Yes, over time it wouldn't be happy because the rod couldn't float from side to side with the pin locks retaining the wristpin. Some timing chain sets use a bronze thrust washer between the camshaft gear and the block, but the COMP Cams Magnum series timing set doesn't. Finally, if you were running a roller camshaft, you'd be using a bronze distributor gear and they have to wear in from initial start-up. They are a service item, and you need to keep an eye on them over the lift of the engine. However, you're using a standard cast camshaft and shouldn't be running one.

PERFORMANCE Q&A

This brings us back to the rear main thrust bearing, because it's usually the culprit. We had a battle with our little 305 eating rear main thrust surfaces. After going through two bearings (slow learner) we finally figured out what it was doing. When the machine shop align-honed the mains, they cut the rear main cap on an angle. This caused the hone to cut a taper in the rear main that was slightly tighter in the rear of the main saddle. This, in conjunction with the cap being slightly cocked on the block, reduced the thrust clearance. We then sanded the rear main thrust surface to achieve 0.004-inch crankshaft endplay, assembled the engine, and thought we were good to go. Well, that slight taper in the rear main would allow the oil pressure to exit the front of the rear main and not lubricate the rear thrust surface of the rear main. Within about 20 dragstrip runs the endplay was about 0.020-inch and guess what we found in the oil filter?

The first thing we'd do is check your crankshaft endplay. If it's still within spec, put a fresh filter and oil in the engine. Put some more time on the engine and give it a good break-in cycle. Service the engine and check the filter for debris. Check the endplay of the crankshaft to see if the clearance has moved. Sometimes on a fresh build things need to get happy with each other. You've identified where the material could come from. Good luck with your break-in.

super mixer a I built a 372ci small-block with a B&M 420 Mega Blower and outfitted with two 750-cfm Edelbrock carbs. Out of all the Hot Rod and Chevy High Performance magazines I have read-and I have read many-l have never seen an article on tuning a 2-4 engine. What concerns me is, remember the old Torker manifold from Edelbrock for a big-block and how the carburetor was turned at an angle for fuel distribution? GM printed info on stagger jetting for this engine, but can you imagine all the mumbo jumbo it will take to get the plugs to read right? Dealing with eight carb holes! Could you please help me on this? Charles Guarisco Silverhill, AL

A The Edelbrock Torker manifolds did turn the carb at an angle to help fuel distribution, but also to help equalize the runner lengths. This helped the distribution of fuel and also the air feeding into each cylinder. As for jetting your blown baby, you have two big mixing rotors directly below the carburetors. These rotors are going to mix the air and fuel and steer the mixture. There isn't anything you're going to do with the jetting of your two four-barrels above the blower that will make much difference in the intake manifold. When you do get down to jetting your engine, you'll want to stay to the safe rich side of the fuel curve. A 12:1 AFR is a safe fuel mixture for your supercharged engine at wide-open throttle. As for part-throttle cruise conditions, you can shoot for 14.7:1, but with the volume of the blower and all the distance from the carbs to the cylinders, you may need to run it slightly on the rich side for good driveability. If you have an issue with distribution, this will cover up most of them. The last thing you want a boosted engine to do is go lean. A quick lean period at full throttle could spell disaster for your engine.

Your best investment would be a wideband air/fuel ratio meter for your car. They have really come down in price and will give you instant feedback on the fuel mixture going into your engine. We've now used about four of the AEM Digital Wideband Air/Fuel UEGO Gauge kits PN 30-4100 in our own race cars, and several of our friends' cars. This completely takes the guesswork out of dialing in the fuel mixture of either a carbureted or EFI system. We prefer the digital gauge, because at a glance you can see the air/ fuel going down the track. They utilize a very quick-responding Bosch wideband oxygen sensor for optimum accuracy and reliability. Another really nice feature is that the sensor has a 0-5V output to be used with data loggers, so that can interface with your race car data logger or laptop EFI tuning software. SOURCE: aempower.com a little spin?

a just finished building a '69 âś“hevelle and have a 598 big-block backed by a Tremec TKO II five-speed with a Ford 9-inch rearend and 3.73:1 gears. I have ladder bars, Hotchkis 11/2-inch drop springs, QA1 double adjustable shocks, and I'm running a P295/65R15 Mickey Thompson drag radial.

I had it dyno'd, and it generated 631 hp at 5,600 and 647 Ib-ft at 4,500 to the wheels. I'm having a little trouble hooking up coming out of the hole and was wondering if I took the ladder bars out and installed a sway bar, would that help or do you have any other suggestions for this situation? This is a full body car with factory front suspension. Trip

Via email

A A little trouble hooking up?

You're trying to control 647 Ib-ft of torque with a TKO II five-speed with a 2.87 first and an M/T drag radial! That gear ratio, coupled up with your 3.73:1 rear screw, gives you a total First gear ratio of 10.70:1. That's a lot of power for a stick-shifted A-body, and it must be an absolute blast to drive. Have you ever tried to take off in Second? The 1.89 gear drops your launch multiplication down to 7.05:1. Yes, that's very high, but 650 Ib-ft of torque is a lot to hit on a small street tire.

Alf Wiebe sells race-only rear suspension designs for NHRA Stock and Super Stock cars that would make the car hook. However, it's a race-only suspension that would put tremendous strain to the rear axlehousing and mounting during street operation. Wiebe won't even sell his system for street use because it will only break parts. We assume you're running bolt-in ladder bars with the factory four-link rear suspension? If this is the case, the rear suspension is in a complete bind. The suspension is trying to move across two different instant centers, and the car must be very stiff (little or no movement). Yes, remove the ladder bars to allow the factory four-links to apply the torque.

Now, let's look at some four-link systems on the market that will allow you to continue driving your monster on the street and give it some more teeth. Check out Wolfe Race Craft, specializing in stock-suspended, small-drag-tire cars that really fly. Wolfe's adjustable four-link suspension bolts into your factory mounting points, and the complete system (PN AWOLDK) comes with adjustable upper and lower control arms and a weld-in double sway bar, which

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