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Projects don't always proceed smoothly, and sometimes things go wrong. Unexpected obstacles arise. It happens to all of us. But part of what makes us hot rodders is the ability to rise to the occasion and overcome those obstacles. At the risk of falling into clichs, that ultimately makes us better people, ready to take on the world at large and make it our own while we pass on what we've learned at the school of hard knocks to those who follow us. That's what we do at Pit Stop; we answer as many of your technical questions as space permits. When e-mailing, don't forget to include "Pit Stop" in the subject line, as well as your full name and hometown or military info in the message. If you have quality digital photos of the car or problem, and if they're at least 300 dpi at 4x4 inches or larger in size (bigger is always better), send 'em.-Marlan Davis
Solid Rollers On Hydraulic Cams
Can you run aftermarket solid-roller lifters on an aftermarket cam originally designed for hydraulic-roller lifters? Other than the profiles of the hydraulic-roller cams perhaps not being as aggressive as the solid-roller cams, what would it hurt? Could the rpm range of the hydraulic-roller cam be extended by using solid-roller lifters? Would the lobe profile on the hydraulic-roller cam be somewhat more forgiving for the valvetrain components than the lobes of the solid roller?
Clyde E. Byrd
Little Rock, AR
With care and within reason, it is often possible to run solid flat tappets on a hydraulic flat-tappet cam and even mechanical-roller lifters on a hydraulic-roller cam. Putting solid lifters on a hydraulic-cam will gain about 500 rpm on the top-end over hydraulic lifters due to the solid lifters' improved valvetrain control-unlike the hydraulic, solids have no bleed-down/pump-up problems. Some hydraulic-roller cams-particularly smaller grinds with 220-240 degrees duration at 0.050-are quick off the seat, but this tends to cause more instability on top. Using solid lifters, even with the existing hydraulic springs, enhances top-end stability and fights the onset of valve float.
Successfully running solid lifters on a hydraulic profile requires some amount of valve lash (a solid lifter cannot run at zero lash or be preloaded). This lash effectively reduces cam duration, especially at low lift off the valve seat (see table). With less duration, peak torque and power occur at lower rpm than would normally be the case for the given combo when running a hydraulic lifter-in other words, the cam acts smaller.
Exactly how much lash is required varies with the specific cam profile, as well as the material the block and heads are made from. Too little lash and you could burn a valve; too much and the valvetrain gets very noisy. Generally the amount of hot lash will vary between 0.004 and 0.015 inch. Such tight hot-lash settings cause problems with aluminum blocks and heads, which see considerable thermal expansion between cold-start and normal operating temperature, so running solids on a hydraulic profile isn't recommended with all-alloy engines. Generally, aluminum heads on an iron block work out OK, with lash expanding about 0.012 inch from cold to hot. With iron heads, expect about 0.008-inch growth.
The more aggressive the lobe, the tighter the lash needs to be. The tighter the lash, the more thermal expansion problems must be taken into consideration. For example, Comp Cam's older Magnum hydraulic-roller grinds usually run fine with solid lifters at 0.012-0.014-inch hot lash. But its newer, much more aggressive Xtreme Energy hydraulic rollers get very noisy over 0.010-0.012 hot lash, so Comp recommends 0.006-0.010 lash settings. When lashing the valves, set them at 0.004 inch cold, then warm up the engine, and recheck it hot. Fine-tune lash settings within the preceding recommendations if the valvetrain is too noisy. Once satisfied, let the engine cool down again and recheck the lash. In the future you can accurately cold-lash the motor.
Some classes restrict competitors to hydraulic lifters. Cheaters have been known to run hydraulic lifters on a solid profile. Because they have no quiet lash ramps, solids make for better race profiles. If you take hydraulic lifters and put them on a solid profile, they generally run better than they would on a roughly equivalent hydraulic profile, generating more area under the curve. Hydraulic cams in general are quicker in low-lift, low-rpm, high-endurance applications. Race motors don't care about vacuum and throttle response; they care about area and rpm. Putting hydraulic lifters on a solid grind raises the rpm points at which peak power and torque occur compared to using solid lifters on the same solid cam. However, the actual power and torque peak numbers at the higher rpm points will be lower using hydraulic lifters. That's because the hydraulic lifters installed on the solid cam are slower off the seat, even though they develop more overall duration. Effectively, the hydraulic lifters installed on a solid grind act like a bigger (but slower) cam with very little increase in flow capacity (no more air, but more time to breathe). In terms of numbers, this means a 249-degree-duration (at 0.050-lift) feels like a 255-degree cam.
To successfully run hydraulic-roller lifters on a solid-roller profile generally requires that the solid cam be a tight-lash (under 0.020-inch hot) profile in the first place, with less than 30 degrees difference between the 0.020- and 0.050-inch duration specs.
Duration Vs. Lash
This shows the change in effective duration at the valve from different valve-lash settings on a Comp Cams Xtreme Energy No. 3315 lobe profile. It assumes1.5:1 rocker arms.
Valve Duration at Lash Lift 0.004" 0.008" 0.012" 0.006" 279.7 273.6 268.6 0.020" 262.5 258.9 255.6 0.050" {{{240}}}.9 238.6 236.5 0.{{{200}}}" 183.2 181.9 180.6Where Do I Get
...a plate-type adapter to use a 700-R4 trans behind the 318 in my '89 Dodge van? Would a GM torque converter be adaptable to the Mopar flexplate?
Don West
Elmwood, IL
Adapter kits typically include the adapter plate, plus a new flexplate, any necessary crank adapter, and miscellaneous hardware. The new flexplate in turn accepts a GM-style torque converter. Kits like this for your application are available under PN 149160 from TCI Automotive (Ashland, MS; 662/224-8972; www.tciauto.com) and under PN 318-350 from Wilcap Co. (Pismo Beach, CA; 805/481-7639; www.wilcap.com)
...a new flasher compatible with the LED light bulbs I'm installing in my '55 Chevy?
John Branson
Scotts Bluff, NE
You need to replace the old thermal flasher with an electronic flasher. Two sources for retrofit units are Hotronics Products (Anaheim, CA; 714/971-8543; www.hotronicsproducts.com) and Ron Francis Wiring (Chester, PA; 800/292-1940; www.ronfrancis.com).
...books that can teach me the basics of high-performance engine building as well as fixing up my '91 Camaro?
Scott Campbell
South Bay, FL
For engine building and blueprinting basics, see the Engine Builder's Handbook by Tom Monroe (ISBN 1557882452) and The Step-By-Step Guide to Engine Blueprinting by Rick Voegelin (ISBN 1884089267). For modifying the Camaro, check out How to Tune & Modify Your Camaro 1982-1998 by Jason Scott (ISBN 076030436X) and Camaro Performance Handbook/Performance Modifications for 1982-1992 Camaros by David Shelby (ISBN 1557880573). These books are available from Amazon.com, Motorbooks (Osceola, WI; 800/826-6600 or 715/294-3345; www.motorbooks.com), and other booksellers.
...resto and performance parts for a '63 Rambler Classic with a 190 straight-six?
Phillip Rovghton
Philo, IL
Three sources close to your neck of the woods are Blaser Auto Nash, Rambler, AMC (Moline, IL; 309/764-3571; www.blaserauto.com), Webb's Classic Auto Parts (Huntington, IN; 260/344-1714; www.webbsclassic.com), and American Parts Depot (W. Manchester, OH; 937/678-7249; www.americanpartsdepot.com).
Ford FE Head ID
I have a set of cylinder heads for what I think is a 390 Ford engine. I found three different sets of numbers and letters in separate places: C8AE-H, D1F, and 7M5. Can you tell me what year and what horsepower these heads are by the casting numbers and letters?
Eddie Loyd
Judsonia, AR
I checked with Tony Knight at the Cylinder Head Exchange, a large Southern California head "core-bank." The basic casting number "C8AE-H" identifies the heads as a common '68-'71 big-block FE casting used on a variety of 360, 390, and 428 applications, including the '68 390/265 or 315 hp, the '68 428/340 hp, and the '69 390 265 or 280 hp. Most varieties have Thermactor (smog-pump) passages,67-70cc combustion chambers, and 2.02-inch intake/1.55-inch exhaust valves. As-cast port sizes were 2.34 x 1.34 inches on the intake side and 1.84 x 1.34 on the exhaust-common for standard FE heads. These heads offer decent performance if larger 2.08/1.65-inch 428-Cobra Jet valves are installed.
"7M5" is the casting date. The first numeral is the last digit of the year the casting was made; the second is a letter that identifies the month; the third and (if present) fourth numerals are the day of the month. The letters representing the month start at "A" for January, and go up from there, except the letter "I" (which in sequence would have been September) is skipped to avoid confusion with the numeral "1." Your heads were cast on December 5, 1967. Ford expert and collector Cliff Jensen says later-dated versions of these heads may have slightly better as-cast flow characteristics due to subtle changes in the short-turn radii.
My sources do not know exactly what "D1F" means, except to say it seems to be present on many of these castings. It may be an internal plant/shift code.
Mopar Magnum 402 Unbalance
I have a new Mopar crate motor for my '67 Cuda project. It is a 402 Magnum (PN P5007647), which is a 360 stroked from the factory. Because I wanted overdrive to go on Power Tour(tm), I chose a Dr. Evil-built A-518 (46RE). I cannot find a SFI-approved flexplate for it. Because it is externally balanced, the issue of either having a balanced flexplate or adding a weight kit to the Hughes torque converter that came with the trans comes up. Mopar Performance offers a weight kit (PN P5249843) to balance a performance torque converter for the new Magnum 360 crate engine. I'm concerned because the 402 has a 4-inch stroke. Would the correct external balance be different?
Mike Reese
Cape Coral, FL
The 402 and 360 Magnum engines share the same amount of external unbalance (which is different than '92-and-earlier cast-crank Chrysler small-block A-motors). You can either add the Mopar Performance "Magnum 360" balance weight and positioning package (PN P5249843) onto your torque converter and retain the existing neutral-balance flexplate, or use an SFI-approved, externally balanced B&M flexplate (PN 10242) and keep the converter neutral-balanced. This B&M flexplate is catalogued for '93-'99 360 engines with an A-727, but it also works for your application as the A-518 (46RE) trans is basically a four-speed/overdrive version of the venerable A-727 three-speed.
TH350 Delayed Upshift
I have a '71 Nova with a TH350 tranny. It has a B&M shift-kit and ratchet shifter. When I manually upshift at wide-open throttle it doesn't shift right away. I usually end up blipping the accelerator to get it to shift before it goes past 6,000 rpm. Is it something with the governor?
Adam Harpold
Mason, OH
Yes-the rpm your governor is presently calibrated for is too high. Although normally the governor controls automatic upshift points, if you manually short-shift at an rpm point lower than the governor's automatic shift point, the manual shift won't occur until the governor is ready. Governor calibration is by means of internal springs and weights (think of it as sort of like a distributor centrifugal advance mechanism). Delayed upshifts sometimes occur when a generic rebuilt trans is installed in a light vehicle, or if the car has steep rearend gears. B&M sells a governor recalibration kit that allows setting upshift points at whatever point is desired.
700-R4 in a G-Body
I have an '84 Cutlass Supreme/Hurst Olds with a nicely modified 350 Rocket. I recently swapped in an '87 Grand National rearend (4.11:1 posi), plus a 700-R4 out of a '69 Camaro Pro Street car (the previous owner went to a six-speed). After installing the transmission plus the required BOP-engine-to-Chevy trans adapter, I found the tranny rides extremely high in the trans tunnel (about an inch between the tranny and the body). Presently, the location of the trans mount does not allow me to use the stock crossmember attached to the stock frame holes. I decided to still use the stock 'member, but I drilled new holes in the frame. Does anyone make a transmission crossmember for my application that utilizes the stock locations? If none are available, other than shortened U-joint life, am I at risk of damaging anything by running it like this? Is transmission performance an issue with the tranny at an angle? When driven normally, the trans performs fine. However, when I really lean into it (which is quite often), it shifts extremely fast up through the gears, not holding any gear for very long. I've ridden in the Camaro when it had this trans, and there were no noticeable shifting problems during hard acceleration.
Rick Swain
Mooresville, IN
Too-quick upshifts are most likely the result of improper TV-cable adjustment, mounting-bracket geometry, and/or overall cable length. In your case, also factor in the odd transmission mounting angle, which may be causing the cable to bind. Details on setting up the TV-cable were last covered in Pit Stop, Feb. '05. Find that issue and make sure that your cable is adjusted correctly, because incorrect TV cable adjustment can cause more than a weird shift; it can also burn up the transmission.
Besides shortened U-joint life, the unusual mounting angle could damage the rear bushing in the trans and may also result in excessive driveshaft vibration. Fortunately, there are several mounting solutions available. G-Force Performance offers bolt-in double-hump crossmembers that besides solving the mounting problems, easily clear big-tube headers and permit easy fabrication of a true dual-exhaust system. G-Force PN RC700 works for normal 700-R4 transmissions with a 22-inch front bellhousing-to-trans-mount distance. There is almost certainly enough clearance in its trans-mount slot to accommodate your adapter plate's added thickness. The G-Force product fits '78-'88 GM A- and G-bodies using the existing front set of holes on the driver side and the only set of holes on the passenger side. Other G-Force crossmembers are available to accommodate a variety of manual and automatic transmissions in these chassis. Although not usually required, G-Force also offers a "half-height" trans mount if post-conversion the installation ends up sitting too high.
Another alternative is to swap your existing 700-R4 extension housing for one with an extra cast-in mount pad located the same relative distance from the front of the trans as a TH400 or TH200-4R mount. Use this housing with the stock crossmember from an '84-'88 G-body factory-equipped with the TH200-4R (RPO MW9). Unfortunately, the crossmember (old PN 14063833) is no longer available new from GM, so put on your dirty clothes and get ready to do the junkyard crawl. The factory TH200-4R crossmember fits only '83-and-later G-bodies, whose framerails were extended to accommodate the new, diagonally mounted crossmember.
Drain Oil Hot-Or Not
I have been doing oil changes for the last 45 years by letting the engine sit overnight then draining the oil for two hours. Oil-change places and auto dealers drain a hot engine for a half hour or so. I tried that and I found the oil to be cleaner after the first day than the way I had been doing it. What is the recommended method of changing oil in an engine?
Richard Brown
Windham, NH
I, too, used to let the car sit overnight before draining, figuring that lets most of the oil drain back to the sump. But technology never stands still. To get the latest thinking on proper oil-drain procedure, I contacted Mark Ferner, Team Leader for Quaker State Motor Oil Research and Development. According to Ferner, it is better to drain the oil when it's warm. The oil's viscosity is thinner when it's hot, so it drains more quickly and completely out of the engine. Also, with a hot engine, contaminants are more likely to remain suspended in the oil, increasing the chances they'll be expelled from the engine during the draining process. Finally, because today's high-tech OHC engines hold oil in a lot more places compared to old-school motors, it's gotta be warm (and thin) to escape from all those upper-end crevices. Bottom line: Drain the oil hot, and let the car sit and keep draining for at least a half hour.
