Thanks Perrib,

So sometimes a bigger engine can get better gas mileage, right? If I understand correct, I want higher gears with taller tires to keep my rpms down,right? I'm thinking of running 30" or 31" 15s for tires. What size vales are in a stock head? Should I run bigger ones? I'm not so much worried about the mileage in sand, mud, and dirt, it just must be good on the street and highway. I'm not looking for a wild engine, just something with good low end torque (do I really need it) for climbing hills and going through mud off road (it doesn't have to be fast there) and still able to reach reasonable traveling speeds on the street/highway with low RPM. 1776 or 1915 don't have as much low end torque as a 1745, 1849, 1904, do they? Does a stroker get worse MPG?

Another thing to think about- typically, more displacement and more hp will cost you reliability (and $$$). I'd guess that Perrib and 57baja's strokers might be somewhat exceptions to this rule, as their motors are both one-off, researched, custom-built labors of love, not the somewhat mass-produced motors non-technical peeps like myself are stuck having built for us by Jethro and Jim Bob, for oodles of coin.

It seems like there's no perfect solution to any dilemma, and this one's no exception.

perrib wrote:

There is more than one Bus owner with a 88x94 or a 90x94 engine with a W100 cam and dual Webber 40s that get 130-140 ft lbs of torque from 2000-4500 rpms.

Is the 94 here bore or stroke?

88 and 90 mm stroke. 94 mm bore. Like AZ 350 states they are not cheap to build correct but neither is a 1600 done right. The basics are a good cooling system. Factory dog house & oil cooler and all the factory cooling tin. Gene Berg has a section in his articles about cooling a Baja. The next problem is oil capacity and filtration. Three quarts and no filter is not good even for a stock Beetle. Along with a head temp, oil temp and oil pressure gauge, full flow oil filter and a thermostatically controlled auxiliary oil cooler is the minimum needed. An exhaust gas A/F ratio meter is also a very good idea. Between the gauges you should be able to keep the engine alive a long time. Now is the time to add more oil capacity. There is really no good way to protected a deep oil sump and retain ground clearance but this is the easiest way to do it but you will have to lower the skid plate. You will lose 2-3 inches of clearance. The other option is a dry sump. These are the first parts to buy so the budget does not eliminate them. On to reliability the less rpm the engine turns the longer it will last. The Engle 100 style cam fits that bill and it does not require a lot of compression which will make the rings last longer. Also the rpm range of the 100 style cam does not require a counterweighted crank so a 1776, 1915 can be assembled cheap. If you are not near a VW Machine shop Rimco can rebuilt your stock crank and rods and rebuild your case. Send them your flywheel, pressure plate and clutch disc them they can balance the rotating assembly. They also sell all the other parts you will need which saves on shipping. The more money you spend on the heads the better. Gene Berg had spent a lot of time developing different port volumes and shapes for all the Engle cams and applications. While not cheap $1200 and up they pull strong at any rpm. They don't trade cfm for air speed. They are custom built for your application.

Next step up would be a stroker. Keeping the 100 cam you can still use the old case if it is still serviceable. I would start with a new case. CB race case comes fully prepped for an 88 stoke.Gene Berg has Engle 100 cam already clearanced. CB may also be able their version of the 100 cam pre clearanced. To keep it cheap use a CB 86 mm crank and CB 5.5 H Beam rods with 3/8 bolts. While chinese they are held to a better standard than the white box parts. You can also use the $600 set of CBs Los Panchitos heads. The longer stroke will make up for any short comings a universal port job may have. I would think the cam followers would be the part to show the most amount of wear. A set of $500 Udo Becker cam followers would cure that. I picked CB because like Rimco you can basically one stop shop from their catalog which saves on shipping and gets parts that should work together. Bob at DeMello Cranks, DRD racing, Brothers Machine, Gene Berg, Competition Engineering can also supply you with the correct parts to build a stroker engine. Keep in mind no matter what you build you will be spending time jetting the carb(s) and the A/F ratio tool is worth the money to jet the carbs correctly the first time. Sometimes less is more. To keep it real simple and inexpensive you could just build a 1776 with stock heads, small Trimill, stock 34 PIC carb and a CB mileage or stock cam.
Still use the full flow oil filter, small auxiliary cooler and gauges. Using a 4.12 RP and 1.48 3rd and 1.19 4th gear will give 56 mph at 3000 rpms and 75 at 4000 rpms with 31" tires.

It sounds like you want to have your cake and eat it too! LOL. When you say that you want good low end and for hill climbing, and good gearing for freeways at high speeds, there's two ways to accomplish that and both have to do with trannies. You can get a Berg 5 transmission (5 speed). One of the guys in our club has one, and it works great. The other way is to have a trans built with a granny gear first and an overdrive fourth. That would leave huge dead spots in your RPM range, though.

My engine would do a bunch better on mileage if it wasn't screaming going down the freeway, and if it wasn't turning 33" tires doing it. A full caged and full bodied car doesn't help either.

perrib is always good for advice and insight, and this time is no exception. I'd probably do things a bit different (such as a 110 cam), but there is truly great wisdom in the points he brought up.

I have a 1-1/2 quart sump and still have adequate ground clearance. I modified my rear bumper as shown here:



If you're running stock suspension it would be tough, though.

As far as driving at high speeds, I have absolutely no troubles at all. I've had mine up to 100 MPH and the only thing scary about it is that it handles so nicely at that speed. If something goes wrong, it doesn't give you much time to react. I try to keep it under 85 when I drive.

Of course, that probably doesn't help the mileage, either.

Thanks Perrib,

OK If I understand correct, A 1904 stroker will cost me more to build, rev higher, and not last as long, right? It would be a better idea to build the 1776 or 1915, and stick with stock heads and crank to get the best mileage, and life out of my engine, and keep the costs down, correct? If I build the 1904 stroker, how much extra will it cost, how much higher will it rev, and how much life will I lose from it? Lastly how will it effect speed and MPG?

Thanks az350x,

Money is definitely tight, but to do it right I may have to shell out a little extra, as long as it is not too much. I know what you mean by non tech peeps, I am one of them. It sometimes confuses me, but I always like to learn what I can.

Thanks 57Baja,

If I can have the cake and eat it too, it would be wonderful. A Gene Berg 5 may be what I'll have to buy, although I may have to wait a while for it. When you say screaming, are you referring to RPMs? How high are they?

i have a 1641cc motor with engle 110 and thats it and i have gotten my car up to 75 ish it takes a little to get the momentum to get there but after that it was just cruising
and i got a 34 pict carb on there that is tuned almost perfect right now so it all depends

Thanks for the info Dan. I'm still thinking I want a little bigger engine.

yeah i hear yeah i want a bigger motor to but just dont have the money for it

Your choice of cam decides what rpm range the engine will run in. Do you need a lot of RPM maybe if you drive like I do. I gave a budget 1776 as a cheap engine option ($1800 with gauges and an A/f ratio meter if your engine is reusable) that will make a difference.
Adding a stroker crank just adds more torque not more rpm. I'm picking the 100 and the smaller CB mileage cams because they do not need dual valve springs so the cam and lifters will last like a stock engine. The 110 needs dual valve springs you can feel the difference just by swapping from single to duals. As far as mileage you only need x amount of HP and Torque to maintain 55-75 mph. That's why it is important to emulate the factory RPM Vs MPH. . .
I thought you were on a budget? It takes a good $4300 to turn a 4 speed into a GB 5 speed and complete the installation. If you build it to make power from 1000-4500 rpms you do not need 5 speeds. Once you get into an engine like mine or 57 Bajas Valve springs need changing at regular intervals. With my VZ style cam the cam followers at 20,000 miles look like they have 80,000.Lifter bore look like they have a million miles. Even a 110 cam beats up cast iron cam followers faster than a stock cam.The simpler you keep it the less "routine" maintenance you will need.

Longer stroke = Greater piston speed = More torque.

Larger bore = More volume pushing = More power.

A 74mm crank would be a fine choice. I have a rev limiting rotor on mine that prevents me from revving past 5800 RPM's. I want my engine to last a good long time. If I was building a good solid motor on a budget I'd stick with the 74mm plan and couple it with 94's for a medium displacement engine that would run great all day long. I think an FK7 with 1.4 ratio rockers, good heads, and a decent set of carbs would work terrific for what you're looking to do. Keep the compression around 8:1 and it will last a good long time. By using a mild stroke, you won't need to get into complications like rod ratios, and Type 4 mains, and you won't need to buy a terribly expensive set of rods and crank. You'll still need to shorten pushrods for proper rocker arm geometry, set your deck height properly, and set your compression by reshaping your combustion chambers, but it is a far less complicated build than going way larger. Of course, it won't be 200 HP, either.

perrib wrote:

Your choice of cam decides what rpm range the engine will run in. Do you need a lot of RPM maybe if you drive like I do. I gave a budget 1776 as a cheap engine option ($1800 with gauges and an A/f ratio meter if your engine is reusable) that will make a difference. Adding a stroker crank just adds more torque not more rpm. I'm picking the 100 and the smaller CB mileage cams because they do not need dual valve springs so the cam and lifters will last like a stock engine. The 110 needs dual valve springs you can feel the difference just by swapping from single to duals. As far as mileage you only need x amount of HP and Torque to maintain 55-75 mph. That's why it is important to emulate the factory RPM Vs MPH. . . I thought you were on a budget? It takes a good $4300 to turn a 4 speed into a GB 5 speed and complete the installation. If you build it to make power from 1000-4500 rpms you do not need 5 speeds. Once you get into an engine like mine or 57 Bajas Valve springs need changing at regular intervals. With my VZ style cam the cam followers at 20,000 miles look like they have 80,000.Lifter bore look like they have a million miles. Even a 110 cam beats up cast iron cam followers faster than a stock cam.The simpler you keep it the less "routine" maintenance you will need.

Thank Perrib,

Yes, I am on a budget. A GB 5 will have to wait for a long time. I was unaware of the high cost I am not sure of the RPM issue. Why would I need alot? How do I build the engine to make power at stated limits? Simple looks good. Low maintenance looks good also. I don't want to be constantly wrenching. I was thinking a stroker to make it up hills and muddy trails without working the engine to hard.

57baja wrote:

Longer stroke = Greater piston speed = More torque. Larger bore = More volume pushing = More power. A 74mm crank would be a fine choice. I have a rev limiting rotor on mine that prevents me from revving past 5800 RPM's. I want my engine to last a good long time. If I was building a good solid motor on a budget I'd stick with the 74mm plan and couple it with 94's for a medium displacement engine that would run great all day long. I think an FK7 with 1.4 ratio rockers, good heads, and a decent set of carbs would work terrific for what you're looking to do. Keep the compression around 8:1 and it will last a good long time. By using a mild stroke, you won't need to get into complications like rod ratios, and Type 4 mains, and you won't need to buy a terribly expensive set of rods and crank. You'll still need to shorten pushrods for proper rocker arm geometry, set your deck height properly, and set your compression by reshaping your combustion chambers, but it is a far less complicated build than going way larger. Of course, it won't be 200 HP, either.

Thanks 57baja,

I don't think I need great HP, but I don't want a wimpy motor either. Do you think I'll get over 100HP with the plan you suggested? Will I still be able to cruise at 65 with out the RPMs being to high? What do you think they will be? What type of MPG can I look at with this set up? 30" - 31" x 15 tires?