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Thu Mar 28, 2019 4:51 pm

I’ve been going round and round on engine sizes and decided an thick wall 92 1835 would be best for my situation and wants. Anyway I’m here to get some advice on more specific things like cam, oil pump, carbs, exhaust etc. My current engine is a very stock 1600 dual port that’s just tired. What I need out the 1835 is this
1. Reliability. I need this engine to work in 10 degrees or 110 without cooling issues. If this sacrifices some power then it’s worth it.
2. Need to have heater boxes. I plan to run stock heads, stock heater boxes with a 1 5/8 exhaust.
3. Low/mid range torque. I don’t plan to rev this engine past 4K regularly and I’d like to keep the revs in stock range for the engine life so high end horsepower isn’t really a must by any stretch. I just want it to pull really well.

As for application this is going in a 74 Super Beetle. Drives around 30 miles every day with mixed highway and in town use. It will be full flowed and if it got 20-25 mpg I’d be thrilled. This is where you guys can help. What would be a good set of carbs (30 or 40mm duals?), mild cam (Engle 100-110?), oil pump (stock or should I go larger?), ratio rockers?

Thu Mar 28, 2019 5:11 pm

1 3/8 header will be more then enough, cb cheater cam maybe and keep the deck tight.

Thu Mar 28, 2019 5:39 pm

The stock heater boxes will choke-off an 1 5/8" exhaust, so yer stuck w/ that handicap. No matter really - they are fine if one is after low end-to-mid range performance.
You could unshroud the stock (tiny) valves & add some mild head porting.
A CW crank would be nice if budget allows, a 12# flywheel & pair of 40mm K-dogs would make it sing.
Get a blueprinted oil pump, bolt-together rocker shafts, FFF setup & just use the native doghouse cooler from the '74 1600.

Thu Mar 28, 2019 5:46 pm

Tims super stock heads, 1.4 ratio rockers with a web 86+5 cam and some dual 40 idf webers and my beehives. Wide and useful power band, smooth and quiet with long term durability.

Dan

Thu Mar 28, 2019 6:04 pm

And just incase you need a translation, K-dogs is the Kadron carbs. Very reliable and easy to install. Good luck with your build.

Thu Mar 28, 2019 6:46 pm

Awesome input. And I knew the boxes would be a restriction but as long as I don’t try to push a lot of air or have high rpm I should be ok right? And I’ll check on those heads. For the crank I’m going to check around and see if I can find a stock welded cw crank for a good price. And not to start WWIII but would the dual 40’s or Kads be better for application or does it matter as long as they are tuned correctly? And I plan on using an SVDA as well. And my transmission should be in good nic but there are always surprises. And should I worry about running ratio rockers or should a slightly larger cam and stock ratio be enough?

Thu Mar 28, 2019 7:22 pm

74SuperScary wrote: I’ve been going round and round on engine sizes and decided an thick wall 92 1835 would be best for my situation and wants. Anyway I’m here to get some advice on more specific things like cam, oil pump, carbs, exhaust etc. My current engine is a very stock 1600 dual port that’s just tired. What I need out the 1835 is this
1. Reliability. I need this engine to work in 10 degrees or 110 without cooling issues. If this sacrifices some power then it’s worth it.
2. Need to have heater boxes. I plan to run stock heads, stock heater boxes with a 1 5/8 exhaust.
3. Low/mid range torque. I don’t plan to rev this engine past 4K regularly and I’d like to keep the revs in stock range for the engine life so high end horsepower isn’t really a must by any stretch. I just want it to pull really well.

As for application this is going in a 74 Super Beetle. Drives around 30 miles every day with mixed highway and in town use. It will be full flowed and if it got 20-25 mpg I’d be thrilled. This is where you guys can help. What would be a good set of carbs (30 or 40mm duals?), mild cam (Engle 100-110?), oil pump (stock or should I go larger?), ratio rockers?

I can add my 2 cents, as an 1835cc DP driver since back in 1976....in Arizona heat, with dealer-added AC for the first 2 decades.
I have thin wall 92s, that's what were available back then. Case and heads were stock except for the larger bores. Crankshaft is stock regrind, not counterweighted, stock 4 dowels. CB Performance oil pump/filter, stock camshaft, quiet exhaust, fan shroud-mounted oil cooler (no doghouse), stock F&S 3-arm pressure plate, stock sprung disc, stock flywheel, stock transmission. Single Weber 40DCNF and German 009 distributor, "quiet" exhaust. I don't go past 4500 rpm "just because". I have plenty of power, cruises nice too; good mix for city and highway; numerous trips to California (and back) in mid-day, mid-summer.

I never experienced 10F temperatures, likely my lowest was 25F; but 110F is just a typical summer day here, measured in the shade. But there is no shade. And temperatures 3 feet above the highway are likely astronomical.

Thu Mar 28, 2019 7:33 pm

I think you'll be more than happy with a:

FK7 on stock 1.1 ratio rockers (crazy quiet) or a W100, single springs

8.0-8.3:1 compression

40 IDF carburetors with 28 vents

Stock boxes with 1 3/8" header

Aluminum pushrods

I drove a 1776cc 90,000 miles before I parked it. It had a FK7 on stock rockers, progressively-wound stock replacement springs on 043 stock valve heads, 3-angle vj with no porting, 8.1:1 cr, 40 idf carbs with 28 vents, and heater boxes with a 1 3/8" Bugpack tuckaway muffler. Got me around 30 mpg on a so-so tune, could move my 67 Bug at 65mph at 2900 rpm on the freeway for 1 1/2 hours in peak California Summer weather, and had plenty of power. I assume the low running temps were because of the valvetrain.

Thu Mar 28, 2019 7:34 pm

I daily drove an 1835 on and off for years (since the 90's) and that engine is in my 65 bus now. Tight deck, 8.something compression, ported small valve heads, and a crane 282 cam with these specs (cam is advanced a bit)
Total lift @ cam 0.0360" @valve 0.407" Rocker arm ratio 1.13:1
Advertised Duration 282* Duration @0.050" 240*
It ran well with dual kadrons for 20 years, and runs great with Dellorto 36's
It currently has an 019 and 1.25 rockers on the intakes, and makes a lot of torque, more than enough for a split bus. I don't wind it out much as I have HD single springs.
SD

Thu Mar 28, 2019 7:51 pm

That’s awesome Cusser and great news for me! And if I can stick with a 1 3/8 exhaust then I will. Also I’ve heard a lot of good from the FK7 from several of the local guys as well so I think that’s set. And the ratio rockers on just the intake valves? I’ve never heard of just one side getting the ratio and the other not. What benefits does this give?

Thu Mar 28, 2019 9:17 pm

74SuperScary wrote: That’s awesome Cusser and great news for me! And if I can stick with a 1 3/8 exhaust then I will. Also I’ve heard a lot of good from the FK7 from several of the local guys as well so I think that’s set. And the ratio rockers on just the intake valves? I’ve never heard of just one side getting the ratio and the other not. What benefits does this give?

I'm running 1.25:1 ratio rockers on just the intakes with a cam that's close to an Engle 100. I'm not very well versed on the effect, someone correct me if I get this wrong, but I think what it does is prevents the exhaust pulses from over-scavenging the cylinders. What that means is that, while the intake and exhaust valves are overlapped, the exhaust pulses can actually suck some of your intake charge out the exhaust pipe. You want some of this effect, to help draw the intake charge into the cylinder, but not too much.

Fri Mar 29, 2019 4:37 am

Coyotemutt wrote: 74SuperScary wrote: That’s awesome Cusser and great news for me! And if I can stick with a 1 3/8 exhaust then I will. Also I’ve heard a lot of good from the FK7 from several of the local guys as well so I think that’s set. And the ratio rockers on just the intake valves? I’ve never heard of just one side getting the ratio and the other not. What benefits does this give?

I'm running 1.25:1 ratio rockers on just the intakes with a cam that's close to an Engle 100. I'm not very well versed on the effect, someone correct me if I get this wrong, but I think what it does is prevents the exhaust pulses from over-scavenging the cylinders. What that means is that, while the intake and exhaust valves are overlapped, the exhaust pulses can actually suck some of your intake charge out the exhaust pipe. You want some of this effect, to help draw the intake charge into the cylinder, but not too much.

2 Thumbs up for this guy! I believe in scavenging and a slight valve overlap

Fri Mar 29, 2019 5:22 am

Good to know! I and probably many others hadn’t thought of that but that’s a good point. I’d like to try that. And for my application it’d probably work well. That with some slightly ported heads would be a good flow help I’d think. Plus the stock ratio exhaust valve may keep the exhaust pressure down. Since I’m running with a smaller exhaust anyway.

Fri Mar 29, 2019 8:21 am

When I said ratio rockers I did not mean stock style rockers. I only use stock rockers on stock or very mild engines. Ratio style rockers are on the left and have many mechanical advantages over stock and by the time you buy all the necessary hardware there is no cost advantage.

Dan

Fri Mar 29, 2019 11:20 am

If you generally drive like with a diesel there is not really any idea in going dual carbs, unless you want it for looks or for the occasional use of the upper end power. I would just go thick wall 1835 or 1914 with a modified stock intake and 34 mm Pict3 carb. Simpler ands easier to maintain and will pull about the same power in the lower rpms if not better.
Go to the engine dyno thread and look for a 1955 std plus bus engine I posted. Copy that except for the crank (Assuming that you want to use stock stroke) you can use detailed stock valved heads too. you can let Modok or Brian e do them for ya. They know how to make the heads so they work well in such combo´s.

Fri Mar 29, 2019 3:09 pm

Dan Ruddock wrote: When I said ratio rockers I did not mean stock style rockers. I only use stock rockers on stock or very mild engines. Ratio style rockers are on the left and have many mechanical advantages over stock and by the time you buy all the necessary hardware there is no cost advantage.

Dan

Interesting. I’m pretty new to much of if the nitty gritty of engine work. So how are your rockers set up? I probably read it wrong so my bad.

Alstrup: I looked at that at that looks like a sick engine! And almost exactly what I’m looking for. I personally think torque is more fun than horsepower and more useful for a daily. I just want to be able to put the foot down and it pull and most of the time that’s between 2000-3000 rpm and I live in Missouri and there are hills upon hills so torque is very helpful. And what jets and changes did you have to do to the carb to get that power?

Fri Mar 29, 2019 4:12 pm

I use the rockers with the adjuster on the pushrod end. The rocker shaft is offset which moves the pivot point away from the valve which reduces guide side loading, valve jobs last longer. If you want lots of torque displacement is the way to get that, 2000cc or more.

Dan

Fri Mar 29, 2019 4:21 pm

Coyotemutt wrote: 74SuperScary wrote: That’s awesome Cusser and great news for me! And if I can stick with a 1 3/8 exhaust then I will. Also I’ve heard a lot of good from the FK7 from several of the local guys as well so I think that’s set. And the ratio rockers on just the intake valves? I’ve never heard of just one side getting the ratio and the other not. What benefits does this give?

I'm running 1.25:1 ratio rockers on just the intakes with a cam that's close to an Engle 100. I'm not very well versed on the effect, someone correct me if I get this wrong, but I think what it does is prevents the exhaust pulses from over-scavenging the cylinders. What that means is that, while the intake and exhaust valves are overlapped, the exhaust pulses can actually suck some of your intake charge out the exhaust pipe. You want some of this effect, to help draw the intake charge into the cylinder, but not too much.

ive thought about running ratios on just the exhaust side for turbo application. but i havent found and good used ratio rockers that used stock rocker shaft size