Blown On A BudgetBob Beckers, Wisconsin: I have a '67 Camaro RS convertible with a four-speed and a '95 GM ZZ3 aluminum-head crate engine (9.8:1). It has an Edelbrock carb, 151/48-inch headers, 211/42-inch mandrel-bent exhaust, a 4.10:1-geared 12-bolt, an HEI, and a cowl hood (with plenty of clearance). My problem is the Joneses, or trying to keep up with them. Most of my buddies run bigger-cube engines, and I've found myself on the losing end of the spectrum. I researched the Pro Charger in a desperate attempt to redeem myself but can't chew on the $5,000-plus it takes to go that route. I have a $3,000 budget and want to get the most bang for my buck. I read and respect the things you've done, and I'm begging for your input. The car is street-driven on 93-octane pump-gas, approximately 500-1,000 miles per year.
Terry McGean: We suspected your quest could be fulfilled for less than the $5,000 you cited, and probably within your $3,000 budget, so we first consulted with ATI ProCharger to see if it could offer an alternative to your findings. Given your specs and budget criteria, the techs at ATI recommended a system using the self-contained P-1SC ProCharger unit. This model is rated to deliver a 30 to 70 percent increase in horsepower on pump gas, and according to the guys at ATI, a complete non-intercooled system can be put together for about $2,700. Although the lack of an intercooler might seem like a compromise, the techs pointed out that since this is a carbureted system, the fuel actually has a cooling effect on the incoming charge air. It will require a Holley carb with mechanical secondaries and nitrile-filled floats, and you'll likely need a fuel pump upgrade also. Intercooling can be added to this system if desired for maximum potential; a universal two-core unit with the tubing kit has an MSRP around $860, while a three-core is approximately $1,100. ATI says the upgrade is fairly simple and can easily be added later on.
We also checked in with Vortech after seeing that it offered a carbureted blow-through system. According to the tech guys at Vortech, the 4GP218-010S kit is considered universal to a certain extent, though it is made for carbureted small-block Chevys mounted in '67-'69 Camaros (with cowl hood), '64-'72 Chevelles, '55-'57 Chevys, and '62-'72 Novas. The kit is based on a tried-and-true V-1 S-Trim blower, capable of providing enough boost to make 750 hp. Also included are the mounting brackets, oil feed and return lines, a carburetor enclosure, a feed tube between the blower and carb enclosure, a crank pulley, and the mounting hardware. You'll have to consult with Vortech to select and purchase the right blower pulley for your combination and you'll also have to fashion an air inlet and filter arrangement for the blower. Summit carries this kit for $2,404.95.
If you want to cut the budget further, you could go with one of the Roots-type mini-blowers offered by Weiand, marketed under the Pro-Street Supercharger line. These are sold in kit form, including the intake manifold, pulley system, gaskets, belt, and hardware. Weiand offers superchargers of several different displacements in this line, though it claims that in general, these kits are typically good for a 25 to 40 percent increase in power. Prices for small-block Chevy 142ci kits start at $1,569 on summitracing.com and increase from there for options like a polished case, Teflon-lined rotors, and larger displacement units. We've actually used these blowers with some success; in fact, some years back we strapped one to a late-model 350 that was similar to a ZZ crate engine and saw right around a 100hp gain. You can also put nitrous on top of them.
Of course, Freiburger recommends going right for the classic 6-71, which Weiand also produces. They're actually pretty reasonably priced, starting at just over $2,000 on summitracing.com for a kit with small-block manifold, the satin-finish blower, 2x4 carb adapter, pulleys, a Gilmer-style belt, tensioner, gaskets, and hardware. Don't expect it to fit under the hood, but according to Weiand, it should add 45 to 55 percent power.
Picking PistonsFrED Markus, Alexandria, VA: I'm getting ready to build an engine for my project car, a '73 Camaro. The engine won't be anything too spectacular, just a fairly sound 383 that will most likely use an aftermarket cast crank and 5.7-inch rods. I haven't decided if I'm going to run Vortec heads or go with aftermarket aluminum assemblies, but I'm hoping the budget is there for the aluminum, and I'm leaning toward Trick Flow 23-degree heads. If I do get aluminum heads, I'll shoot for 10.0:1 compression. My cam will be a flat-tappet hydraulic with about 0.525-inch lift and mid-230-degree range at 0.050. The car will be used for weekend fun on the street and occasionally at the track, and I'd like the car to have the capability of running 12s, though I realize it may take some nitrous to get there. That brings me to my main question: Do I need to run forged pistons, or will hypereutectics be acceptable? It seems like in the old days, all performance engines had forged pistons, but now that I'm shopping, most reasonably priced slugs are hypers, and most of these are marketed as high-performance pistons. I don't want to skimp, but I also don't want to spend money on pistons that could go toward my heads if hypereutectics can handle my needs. With eventual upgrades, I'd like this engine to approach 500 hp at the flywheel, or at least be strong enough to handle that level of power. I'm thinking of a 150hp shot of nitrous too. Will hypereutectic pistons disintegrate under these conditions?
Barry Rabotnick, Federal-Mogul Product Manager, Performance: You'd think a straightforward street/strip-style engine build would be easy, but this is actually the toughest application to pick a set of pistons for because many different choices will work. There's a lot of confusing information and marketing hype regarding the benefits of one material or design over another. Let's try to cut through the noise and make some clear decisions.
Pistons for automotive engines are manufactured using one of two methods: forging or casting. In addition, there are a couple of popular aluminum alloys for each method. Cast pistons for high-performance use are almost always made from hypereutectic alloy, which uses a high percentage of silicon (over 16 percent). Silicon in piston alloys improves wear resistance and adds strength at the cost of ductility (flexibility). Forged pistons are made from either 4032 alloy, which has about 11 percent silicon, or from 2618 alloy, which has greater high-temperature durability but essentially no silicon. For forged pistons, the 4032 is a better choice for long life in street and bracket cars; the 2618 is better for true race applications where long service life is less important than durability under extreme stress.
Hypereutectic pistons have a definite cost advantage over their forged counterparts. They'll perform great for the street and can survive a fair amount of racing abuse. The other advantages of hypereutectic pistons, including tighter operating clearances, are really minor compared to the cost benefit. In computer-controlled, fuel-injected, knock-sensor-equipped vehicles, hypereutectic pistons will survive at power levels well beyond those you're considering; carbureted applications call for more caution. Forged pistons of any alloy will easily handle the power you're going be making. The real difference is what happens if and when the piston you've chosen fails. A hypereutectic will crack and possibly break, where a forging will normally deform or go "plastic," causing less damage to other engine parts. The choice is therefore based on the likelihood of failing the engine, rather than on how the parts perform when everything is OK. A daily driver goes hyper, a real racer goes forged-you're in the middle.
Out of respect for your budget, I was ready to send you to the store for a set of hypereutectics until I read that sentence about a 150 shot of nitrous. If you can keep your nitrous boost at that modest level, I still think a hyper would be a good fit, considering the cast crank and the generally mild nature of your engine. If you think that you'll be bumping that bottle a little harder (I have yet to meet anybody that thinks they have enough horsepower), I would consider moving to an entry-level set of forged pistons just to be safe. A set of basic forged flat-tops will cost you only another hundred bucks, but it might be cheap insurance.
'This guy wants an aftermarket cast crank with 5.7-inch rods. He'll probably need to add Mallory to balance the thing. He'd be money ahead with 6.00-inch rods.
Ask AnythingAsk Anything is the portion of What's Your Problem where readers send questions for industry big-wigs, then we get the answers. So pick a hero and e-mail your query to CarCraft@primedia.com.
'Barry's last name reminds us of Rabbot, the giant robot bunny who destroyed Carl's car on Aqua Teen Hunger Force.
The Cadillac Of Small-Blocksdroopy1907, via CarCraft.com: A guy at a salvage yard told me that some LT1s came out in Cadillacs. Does anyone know that to be true? Terry McGean: Yep; despite converting almost its entire line to front-wheel drive in the mid-'80s, Cadillac continued to offer a rear-drive model until the '96 model year. The Fleetwood Brougham was based on the same architecture as the Chevy Caprice and Buick Roadmaster, and like them, the Cad version received the LT1 engine for '94 to replace the 350-inch throttle-body injected small-block Chevy used previously. Most sources refer to all of these cars as GM B-bodies, but in fact, the Cadillac is actually a D-body. The only real difference is a longer wheelbase. If you were to find one of these Cadillacs in the junkyard it would have the same 260hp iron-headed LT1 found in the Caprice of the same vintage.
Throwing A CurveR.L. Hutchison, San Angelo, TX: I've got all my pieces together for my '76 Comet but I'm having motor setup problems. At 4,000 rpm at WOT in any gear, the motor seems to lose power. The motor is a 0.060-over 302 with 9.2:1 compression, Trickflow Twisted Wedge heads and roller rockers, Comp Cams 268H cam, Edelbrock Performer RPM intake, Hooker 151/48-inch long-tube headers, ACCEL distributor and 300+ CD ignition, and an Edelbrock 750-cfm carb. I know the carb is a little large, but it's what I had. The power runs through a T5 five-speed trans to a Currie Enterprises 3.89:1 TSD differential and out to the 245/60R14 BFGs. The car weighs about 2,800 pounds. The problem only happens under load, which is why I suspect ignition timing. Timing is set at 21 BTDC, which I think is too much, but the motor runs well and makes good manifold vacuum (about 15 inches) at idle. The distributor mechanical advance is the way ACCEL shipped it to me (all in by 3,600 rpm), and the vacuum advance is disconnected because even 2 degrees of additional advance creates a misfire under light load. I guess I don't understand enough about timing curves. Please help.
Jeff Smith: It sounds like you've put way too much initial timing in the engine in search of a smoother idle. The Comp 268 cam isn't that radical, but its additional overlap will pull the idle vacuum down to about 10 or 12 inches of vacuum at around 900 rpm or so. In your case, with 21 degrees of initial timing, you have too much total mechanical advance at higher engine speeds, which is why the engine lays down. While we don't know the exact model of the distributor you're using, ACCEL's John Hrinsin tells us that if it's a relatively new distributor, it probably has around 24 degrees of total mechanical advance. Add in your 21 degrees of initial, and that's 45 degrees of total timing at or above 3,600 rpm. This means you're starting the combustion process very early, so at higher engine speeds, the engine has to work against greater cylinder pressure that's building before the piston gets to top dead center (TDC).
So here's the fix: First of all, use a dial-back timing light or a timing tape so you can measure total mechanical timing. Let's assume you're at 45 degrees above 3,600 rpm. At idle, set your initial timing at 12 degrees BTDC and recheck-you should then have a total mechanical advance of 36 degrees: 12 + 24 = 36 degrees. The idle vacuum will drop slightly, but it should still be reasonable to run accessories like power brakes. Now, you will be able to reconnect your vacuum advance and adjust it to add in perhaps as much as 6 to 8 degrees of additional timing at part-throttle. Be sure to hook the vacuum line to the distributor from a ported vacuum source on the carburetor, not manifold vacuum. Ported vacuum on any carb is a source where there is no vacuum present until the throttle is opened slightly. This eliminates vacuum advance at idle, which isn't necessary. Remember when checking total mechanical advance to disconnect the vacuum line to the distributor, otherwise you will be reading total advance including the vacuum advance.
Should you prefer more initial timing than our suggested 12 degrees, you can modify the distributor to reduce the total mechanical advance. For example, if you desired 18 degrees initial but found that 36 degrees total was optimal for best power and the distributor had 24 degrees total mechanical advance, this would require modifying the distributor to limit mechanical advance to 18 degrees (18 initial + 18 mechanical = 36 degrees total). Some Ford ACCEL distributors use a GM-style mechanical-advance system placing the weights and springs just under the rotor. If this is the case, look for a pin with a bushing under the advance weights. Using a larger bushing that limits travel in the slot will reduce the total mechanical advance.
That's the scoop on ignition advance. You can experiment with total ignition timing, the rate at which the timing advances, and the amount of initial timing by juggling the major players. By doing so, you will see a huge difference in power while spending almost no money. It's all about spending a little time with your engine.
Dept Of CorrectionsIn the August '05 "Ask Anything," we conferred with Jay Buckley on the subject of brakes, but it looks like we made a couple of mistakes. All of the actual tech info was on the money, but we referred to Jay as a "brake engineer" when in fact he is a brake training manager and considered the Bendix Answerman. We also referred to his employer as the Bendix Friction Materials division, but it turns out that technically, it is Honeywell Friction Materials. The lawyers should now be appeased.
Blow This JointPage_19, via CarCraft.com: How do you get your U-joints out if there are no snap-rings?
Terry McGean: It sounds like you're talking about the '80-era GM style of U-joints that use plastic retainers in place of traditional snap-rings. If you look at the yoke you should see a small hole in the side of each "ear" that has what appears to be a small plastic plug. That plastic is actually just the tip of a retainer that holds the U-joint caps in place. Beating with a hammer will likely prove futile unless you get out the B.F.H. and really go to town, which may wind up tweaking the ears of your shaft or the yoke. Instead, get your hands on a small propane torch and heat up the caps. The plastic should start to ooze out of the holes. When it stops flowing, you should be able to press the caps out with relative ease. Replacement U-joints will include snap-rings that fit into grooves on the inner portion of the caps.
A word of caution: Using the standard motorhead's bigger-is-better operating rule, many guys seem to think that if a propane torch works well, an oxyacetylene torch will be even better. However, when you apply too much heat, the grease under the cap gets super-heated and basically explodes, firing the cap off the joint right around the time the retainer ring has completely melted away. Catching a red-hot projectile in the face is rarely fun, nor is shooting one into your paint job. Mild heat should do the trick. The Electric 400 Slide Kris Shields, Granada Hills, CA: I recently purchased a used 4L80-E four-speed automatic overdrive from a heavy-duty truck for a great price. I want to put it in a '65 Chevelle that I'm building. After purchasing the transmission, I noticed that the rear yoke bolts into the back of the output shaft rather than as a slip yoke that I've seen on all other automatics. Can I put a regular Turbo 400 yoke in place of this bolt-in yoke? It also looks like the trans mount is farther back than a TH350 or 400 trans.
I know that I will need a separate computer to run this transmission, but I'm not sure how expensive these are or what exactly I need beside the computer and a wiring harness. Will the aftermarket harness bolt right into the transmission case? I'm also going to need a different torque converter. Will a Turbo 400 converter bolt up to this 4L80-E? Thanks for your help.
Jeff Smith: We did some research for you, Kris. The 4L80-E, as you probably know, is similar to the old TH400 automatic fitted with an Overdrive. The First through Third gear ratios are the same (2.48, 1.48, 1.00:1) while Overdrive is a typical 0.75:1 or 25 percent overdrive. The truck-style bolt-on yoke is easily removed and a typical TH400 yoke can be substituted (TCI PN 965300, $129.99 summitracing.com).
You're also correct that the transmission requires the use of a standalone computer to control the shifting and pressure. TCI offers a separate computer, software, and wiring harness package (PN 377000, $659.95 summitracing.com) that allows you to control the trans via a laptop computer. You will also need a throttle position sensor (TPS) input into the computer to indicate wide-open throttle. TCI offers the sensor and an adapter package for carbureted applications (PN 377400, $199.95 summitracing.com), but you could buy a GM TPS sensor and adapt it to your carb for much less. Other required connections include a tach signal and 12-volt power to the trans. You'll also need a specific 4L80-E converter since TH400 converters will not interchange. The 10-inch TCI StreetFighter converter (PN 242900, $399.95 summitracing.com) is a good choice, but several other companies such as Hughes and High Impact Transmissions also offer converters. TCI also makes a 4L80-E locking filler tube (PN 743805, $64.69, summitracing.com).
We also found a company called Powertrain Control Solutions that sells a standalone control computer for the 4L80-E as well as other transmissions. This ECU sells for $700 and requires a $150 wiring harness but offers intriguing opportunities such as converting to a paddle shifter control. Shiftworks also offers a four-speed auto-shifter conversion detent kit for stock shifters as well as an extension housing conversion for $495 that converts the tailshaft to a mechanical speedometer. These electronic controllers will also work for the 4L60-E and 4L65-E "electric" overdrive transmissions. For you EFI fans, BigStuff 3 offers the combination of its impressive EFI controller with a built-in transmission controller all in one black box and the price is definitely less expensive than adding a separate controller for the trans.
The 4L80-E is a monster trans that's both heavier and longer than a standard short-extension-housing TH400. It will require the transmission crossmember to be reinforced and moved rearward. There are three different-length TH400 cases and three different-length 4L80-Es, so the variations are numerous. But with this heft also comes incredible strength and durability.
'Heh, heh ... B.F.H. is cool.
TRANS LENGTHS Overall Engine to Length Crossmember (A) (C) TH400 2831/48 26151/416 TH400 33271/432 27151/416 TH400 3771/48 27211/432 4L80-E 32111/416 3031/48 4L80-E 31151/416 3031/48 4L80-E 33 3031/48 4L80-E (4x4) 29 3031/48You Got Problems? We've Got Answers!CarCraft@primedia.comCar Craft Mag6420 Wilshire BlvdLos Angeles, CA 90048
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