Help me plan my bus engine? 78mm x 90.5?

[W1K1]

There is also the link at the bottom of my signature for jim Martins engine build and:
http://www.aircooledtech.com/engine_build/
_________________
http://www.thesamba.com/vw/archives/manuals/jim_martin_engine_build.php

1973 super
1965 squareback 1500E
1971 bay window westy- subi swap

[Alstrup]

Web 218 all the way.
A little less peak torque compared to fk65, but a LOT less valve train noise and wear. Also less head temp. You can use single HD springs. I like to shim them 1 mm. ACN ally pushrods would be very nice.
As for heads. If you want massive lower end torque, have a good head guy make you a set of 043´s with 35/32 or 37,5/33 mm valves. Have him make the ports "hi velocity". It - will - kill the upper end performance somewhat though. My 1955 bus version pulls 115 - 117 hp @ 5300 and 170 Nm torque at 3200 with heads that are similar to CNC round port. doing it with smaller valve heads with good ports can pull the torque further down by roughly 250 rpm. and take 5 - 10 hp out on top.
I dont remember the reduction ratio of the big nut boxes for sure. But you should aim for a final ratio that equals 18,6 to 19 M/1000 rpm. No more.
Also, make sure that the engine gets ALL the air that is possible. I often drill a 2½" hole in the front plate just above the starter, to allow more air into the engine compartement. (If you drive a lot of off road this is NOT a good mod, as it will then suck a lot of dust into the engine compartement.)

Living up in the thinner air allows you to up the CR a bit. How much I am not the one to tell. At sea level I set these engines up for 95 octane Euro fuel. (About 91 US) And that is 8,6 - 1. I would buy some of the stuff from John @ ACN and get his angle on that.

T

[Moz'z58]

This is just my experience with a heavy camper, often loaded for long travel on and off-road. Lots of opinions around, not sure how many of them have 110,000 heavy Kombi road miles to base them on however. I live @ 3100' elev since '91 and drive snow/cold to hot summer heat in sierra foothills. This is a longish post to give info's-apology if tedious but likely you'll find others with real Camper and bit more HP in concurrence.

My bus is a '65 Kombi (was a westpahalia, now custom camper as it was rotted beyond repair) I've owned since 1986. In '89 I did the Berg recommendation for busses using their kit for a 1.7L 88x69 welded cw crank, 12# flywhl and 1700# clutch p/p/solid disc. The cam they sent is there gb296 = 276 duration and .374" lift, stock 1.1:1 rkrs, solid shafts and dual springs and their retainers , steel P-rods. Stock size valvesx3angle. Sump and full flow and berg relief cover. I use a 96 plate ext cooler in the summer. Disconnect it in winter. 6.9:1 CR.

I used 40 idf's on Berg manifolds w/ 009 for first 33k mi's then switched to Solex 40's. Not really necessary maybe but I felt the IDF's were too much carb for 1.7L and the Solex run smoother - still w/ 009.

This engine configuration has served me very reliably which is all I was/am interested in. My ideal was a 78mm berg crank but was more money than I wanted to spend back then. Still enough torque w/ 69 to do fine Kombi duty IMO/IME.

I have to disagree with the common statements that a 3.88 R&P is bad news in a bus. I use side scoops for CFM increase to the doghouse fan, and temps stay just fine @ Clyheads and oil. Split the diff if you get paranoid and go w/ 4.12, but many use 3.88. My opinion is many are building engines with very high CR into a heavy bus, driving long hot hours, and then blame a 3.88 if it's installed. Whatever.

If your climbing logging roads all day cutting firewood for a living then 4.37 may be best w/ the added HP, but I have no problem pulling uphill out of camp sites with a load. Keep in mind there is not much difference in the lower end gearing as opposed to tallness of 4th between the 4.37 and 3.88. The OG 4.37 was doing duty w/ much less HP and torque - the '65 w/ 1500 SP and Solex30 was considered a big step up in the day.

I went to 3.88 after a side gear went through the circlip and pulled the tube away from the bell flange due to fast mountain cornering driving in a loaded up bus. I bought the center from Transform in LB in 1992, and kept the R-boxes all the same. No problems since and 73,000 mi.

With the OG 4.37 and new 1.7 I was running high rpm's on hiway to reach 60mph and that bugged me. I was OK with that @ 1600 and single solex 34 for the first few years cruising 50-55 to keep the engine sane and safe, and generally took it in stride, but w/ new engine power 300+ mi trips from home to a destination took longer than necessary due to the R&P limitation . But the all new 1.7 it just didn't make sense anymore. I cruise at 2800-32/3400 and whatever that nets in mph relative to tire size. Right now I just put on Wintertraks @ 205/75/15 rears and the speed has jumped up to 65 mph. But I have cut wells and 6" steel spoke rear and 14" bay rims up front on BusBoys conversion disc brakes I added in '88-very worthy in heavy camper mountain driving - I got tired and scared of the fade on steep grades with all that weight. Really long reply but is my direct and still continuing Kombi experience. The trend now is all stock and I love them. But I like disc brack and the added track width I have and better handling result.

Have fun, and don't forget the dual valve springs and steel push rods with your dual carbs in heavy bus. Also pay to have it all balanced together if you can

[Splitdog]

With GRB's I'd stick with a small cam. Enjoy the bottom-end torque where you'll be at most of the time anyway. Letting the clutch out and bogging every time is bogus. I have a 1600 with dual kadrons and a 100 cam. I think that cam is too big. It doesn't come on until about 2300 RPM. So between 1500 and 2300 you get the bog. I have 8:1 CR.
_________________
CH³NO²

Z = z² + C

Der Blitzkrieg Kafers

#notacallooker

[Alstrup]

[tdubz510]

So, I'm thinking of buying a 59 Kombi that lives in flat Florida, that I want to turn into a West Coast camper/tourer.

I live in NorCal and want to be able to get to the mountains and National Parks and hot springs and such....you get the idea..not a flatland cruiser!

I want a very dependable, strong bus that will be moderately loaded down with a SO33 style custom interior for long spring and summer road trips..

Bus as is has been modified to a stock 73 type3 squareback transaxle, a very dependable 1600 beetle engine built on a fuel injected block...
I don't know the ratios in the transaxle..and I don't know crap about engines and transaxle ratios you guys were speaking of earlier to be honest!! lol

I'm thinking of going up in engine size to 1835.

I got a recommendation for an engine upgrade from a builder of engines:
a super street 1835cc full flow engine with 92mm thick walled pistons, a counter crank, stage 1 clutch, and A1 exhaust.

Think this is a good power upgrade with said 73 transaxle for my camper/touring plans for this bus?

Should this transaxle the PO has put in need to be changed to OG for better torque in some mountain roads??

Thanks for you help!!

[mark tucker]

dont. if it runs, leave it alone!! and then start buying all the new peices you need to build a 82mm ~84mm stroke engine with cnc chamber lost pan of cheetos heads & CB uniteck rods to fit the crank. cb probably has the cam you want too. and get the aluminum engine case thats stroked .slot the lifter bores and use a 30 mm oil pump, pumping out to the filter than cooler then back to the case. use the wide glade sump, dont use the filter in the sump, just the extended cb puckup tube into a oe style screen. and use total seal rings too.piston size of your choice. dont short change your self.you will just end up with a mess at the swapmeet.