I have a dual port 1600 in my 56 Beetle. This winter I plan on removing and dissassembling it due to a oil burning issue. I want to keep it a 1600.
I need some advise, with the rebuild. want to put an Eagle 100, or 110 cam. 1.25 rockers. Does anyone have any suggestions about lifter, valve spring, push rods. Also was thinking about straight cut cam gears. Any advice would be great.. Thanx in advance...
mild mod 1600...
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Marc
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Re: mild mod 1600...
I assume you mean Engle W-100 or W-110.
What carburetion will you be using? Heater boxes/exhaust system? What gearing and rear tire size, and how will the car be used? I presume you aren't intending to do any head porting; would you always buy more expensive fuel if it needed it, or would you prefer to be able to use the cheap stuff with impunity?
What carburetion will you be using? Heater boxes/exhaust system? What gearing and rear tire size, and how will the car be used? I presume you aren't intending to do any head porting; would you always buy more expensive fuel if it needed it, or would you prefer to be able to use the cheap stuff with impunity?
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jksampson
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Re: mild mod 1600...
Sorey for the mis spell. Its a weekend car, about 2k miles a year. Yhe carbs are dual 34 pic . Yire size in the rear are 195/50r15. Gas grade isnt any issue. I was going fo.research rejetting the carb to..
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jksampson
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Re: mild mod 1600...
The exhaust is gt muffler with no heater boxes. Havent really yhought about head work. Again im looking for advise..
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Marc
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Re: mild mod 1600...
Sounds like a pretty mild combo, something that should live without 8-dowelling the crank/flywheel...not cost-effective to pay for head work IMO. What transmission are you running?
The W-100 w/1.25 rockers comes pretty close to emulating the W-110 w/1.1s. Neither grind was actually designed for 1.25s (they didn't exist back then), but there's sufficient safety margin built in that they're OK to run...but if you haven't purchased a cam yet, why not save some money and use the W-110 with stock rockers?
Or, if your stock cam is still in good shape you might consider recycling it with some 1.4:1 rockers and HD single springs. If the lifters are still good (and you don't mix them up) that could save you quite a bit and the performance would be similar to the W-100.
New stock springs (w/shims) and healthy stock rockerarm assemblies (no worn wavy washers or springclips) should suffice - they will work up to the RPM you'd be making power at with either cam if the valvetrain weight's not excessive - i.e. w/stock adjusting screws. With a stock crankshaft it's not advisable to exceed 5000 RPM or so. Personally I prefer to err on the side of caution and build the valvetrain slightly stouter than minimum requirements, so I'd be going with "solid" shafts, HD aluminum or steel pushrods, HD single springs, and swivel-foot adjusters from the outset rather than wait to see what fails first...but if you're feeling lucky, none of that stuff is absolutely mandatory for an engine that should be "all done" by 5 grand.
Be sure to check the port-matching of the intake manifolds to the heads, and if necessary open the head ports up to eliminate any step. Some would advise a static compression ratio of around 9:1 for the W-110, and if you don't mind buying more expensive gas that's not outlandish...but there's only (at best) 2 HP difference between that and a <8:1 motor that can swallow Regular day in and day out, for my money not worth the cost at the pump.
Straight-cut timing gears improve cam thrust-bearing life by eliminating the longitudinal motion of the cam caused by the resistance of the valve springs - until you're running some pretty stiff springs there's not much to gain there (other than an arguably "cool" whirring noise). For a typical street engine with single springs they're kinda pointless IMO - for a couple bucks more you can get a set of cam bearings with "double" thrust shells which should be enough to last the life of the motor.
If you find that your oil consumption problem is due to excessive piston/cylinder wear and need to buy a new set, consider the AA "thickwall slip-in 88s" which require machining of ONLY the heads and boost your displacement to 1679cc...that is, unless you're still running the `56 split-box trans
I've schucked flywheels by abusing 1679s though, so if you don't 8-dowel you'll need to control yourself.
The W-100 w/1.25 rockers comes pretty close to emulating the W-110 w/1.1s. Neither grind was actually designed for 1.25s (they didn't exist back then), but there's sufficient safety margin built in that they're OK to run...but if you haven't purchased a cam yet, why not save some money and use the W-110 with stock rockers?
Or, if your stock cam is still in good shape you might consider recycling it with some 1.4:1 rockers and HD single springs. If the lifters are still good (and you don't mix them up) that could save you quite a bit and the performance would be similar to the W-100.
New stock springs (w/shims) and healthy stock rockerarm assemblies (no worn wavy washers or springclips) should suffice - they will work up to the RPM you'd be making power at with either cam if the valvetrain weight's not excessive - i.e. w/stock adjusting screws. With a stock crankshaft it's not advisable to exceed 5000 RPM or so. Personally I prefer to err on the side of caution and build the valvetrain slightly stouter than minimum requirements, so I'd be going with "solid" shafts, HD aluminum or steel pushrods, HD single springs, and swivel-foot adjusters from the outset rather than wait to see what fails first...but if you're feeling lucky, none of that stuff is absolutely mandatory for an engine that should be "all done" by 5 grand.
Be sure to check the port-matching of the intake manifolds to the heads, and if necessary open the head ports up to eliminate any step. Some would advise a static compression ratio of around 9:1 for the W-110, and if you don't mind buying more expensive gas that's not outlandish...but there's only (at best) 2 HP difference between that and a <8:1 motor that can swallow Regular day in and day out, for my money not worth the cost at the pump.
Straight-cut timing gears improve cam thrust-bearing life by eliminating the longitudinal motion of the cam caused by the resistance of the valve springs - until you're running some pretty stiff springs there's not much to gain there (other than an arguably "cool" whirring noise). For a typical street engine with single springs they're kinda pointless IMO - for a couple bucks more you can get a set of cam bearings with "double" thrust shells which should be enough to last the life of the motor.
If you find that your oil consumption problem is due to excessive piston/cylinder wear and need to buy a new set, consider the AA "thickwall slip-in 88s" which require machining of ONLY the heads and boost your displacement to 1679cc...that is, unless you're still running the `56 split-box trans
I've schucked flywheels by abusing 1679s though, so if you don't 8-dowel you'll need to control yourself.-
jksampson
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Re: mild mod 1600...
So what your saying is a stock cam, with 1.25 rockers and HD springs will give me rhe same results.
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Marc
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Re: mild mod 1600...
No, but with 1.4:1 rockers it'll come close to the W-100 in overall performance - in other words, ~3HP improvement if the valve springs are good for at least 5000 RPM.
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jksampson
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Re: mild mod 1600...
I do have a set of HD spring new in the box, that I bought at a swap meet about 1 yr ago. I really dont want to split the case if I dont have to. You said 1.4.1 rockers, are the different then the 1.25 rockers. If there is anything else that you recommend. Please let me know.. Thanx for your time.
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Marc
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Re: mild mod 1600...
1.25 rockers yield a valve lift that's 25% greater than the lift at the cam lobe, or ~14% more than you get with stock 1.1 rockers...barely enough to justify their expense IMO.
1.4s yield about 27% more lift than stock...twice the improvement.
An Engle W-100 has .383" lobe lift, or .421" valve lift with stock rockers or .479" with 1.25s.
A stock cam has ~.324" lobe lift, so 1.4s yield about .453" valve lift.
The W-100 has more duration than stock, but the 1.4 rockers on the stock cam will get the valve open to the point where it's actually flowing significantly nearly as quickly as will stock rockers on the W-100.
While the characteristics aren't identical, they're so close that few folks would be able to tell the difference by the seat of their pants - so if you don't need to open up the bottom end at this time, the 1.4s are an option that's worth considering...like the slip-in thickwall 88s.
One drawback to increasing the rocker ratio is that it often necessitates using shorter pushrods to establish correct rockerarm geometry; also, the entry-level 1.25s are merely 1.1 parts that have had the pushrod cup machined closer to the shaft, which raises the pushrod in the tube and may cause interference. TRUE ratio rockers come with shafts and support stands with offset mounting holes to shift them down, which keeps the pushrod centered in the tube.
IMO the HD singles should be used for any combination involving a cam or rocker ratio that's greater than stock, with the possible exception of the W-100 using stock rockers. When you install them, fit a .015-.020" steel shim under each one to keep them from gnawing into the head, and sand the keepers so they "pinch" into the valve stem...you need to remove enough material from the flat face of each keeper so that when you hold a pair in place against the valve, with them touching at one end, there's about a .010" gap between them at the other end. This locks the valve in place better than the stock arrangement which allows it to spin between the keepers - that slop can also lead to the grooves/lands of the valve stem being damaged in operation.
1.4s yield about 27% more lift than stock...twice the improvement.
An Engle W-100 has .383" lobe lift, or .421" valve lift with stock rockers or .479" with 1.25s.
A stock cam has ~.324" lobe lift, so 1.4s yield about .453" valve lift.
The W-100 has more duration than stock, but the 1.4 rockers on the stock cam will get the valve open to the point where it's actually flowing significantly nearly as quickly as will stock rockers on the W-100.
While the characteristics aren't identical, they're so close that few folks would be able to tell the difference by the seat of their pants - so if you don't need to open up the bottom end at this time, the 1.4s are an option that's worth considering...like the slip-in thickwall 88s.
One drawback to increasing the rocker ratio is that it often necessitates using shorter pushrods to establish correct rockerarm geometry; also, the entry-level 1.25s are merely 1.1 parts that have had the pushrod cup machined closer to the shaft, which raises the pushrod in the tube and may cause interference. TRUE ratio rockers come with shafts and support stands with offset mounting holes to shift them down, which keeps the pushrod centered in the tube.
IMO the HD singles should be used for any combination involving a cam or rocker ratio that's greater than stock, with the possible exception of the W-100 using stock rockers. When you install them, fit a .015-.020" steel shim under each one to keep them from gnawing into the head, and sand the keepers so they "pinch" into the valve stem...you need to remove enough material from the flat face of each keeper so that when you hold a pair in place against the valve, with them touching at one end, there's about a .010" gap between them at the other end. This locks the valve in place better than the stock arrangement which allows it to spin between the keepers - that slop can also lead to the grooves/lands of the valve stem being damaged in operation.