ShopTalk Forums | Aircooled VW Tech & Restoration Help

Well I am pissed with the Samba Forums because i am tired of answers like "its fine the way it came from the factory" crap.
I hope there are more people here that understand building up from stock is fun.

anyway I am building my bus to run the 1/4 mile. I am trying to get in the 16 to 18 sec range. and i want to do this while keeping it a 1600. I know this sounds it might be hard , But I want to try. you know for the fun of it.

if anyone has issues stop reading now, and no response required.

ok I am at 22.31 right now.
my stats are
1600
holley bugspray 300 cfm
holley intake
1.4:1 ratio rockers
hi rev springs
hd pushrods
merged exhuast with stinger
stock tires

I am thinking of porting the heads and flycutting
it seems that at 4500 to 4700 I lose a lot of power. I think it is due to lack of air through the stock heads.

another thing that is a issue is the transmission is only mounted at the front and at the mustache bar. so is there another way to mount the tranny? I saw in later model bays that the transmission was mounted at the bell housing. could i use this mount on a 71? or even use some type of tranny strap like used in beetles?
I was also thinking using urathane mounts at the mustache bar.

this is just trying to prevent the next weak spot from failing.

Are you open to turbo?

As for the purist mentality and the associated grief...you need not worry, that doesn't apply here.

No I'm not against it. I just wanted to try to do it NA first.
I helped a friend turbo his 1600 singlecab and he made low 17's on his first pass.

Check this page out. yes, it's an article that is like 30 years old and doesn't give A LOT of technical details but it will get you started in the right direction. I know I've seen the more in-depth details some place, I think even on that site but for the life of me I can't find them. Must be old age. 126hp out of 1600cc. I figure if they can get that type of power out of an engine 40 years ago for rally, you can improve on it for drag racing now.

Where's the link

Welcome to the STF!

My guess would be the manifold/end castings are more of a limiter NA than the heads...

Might want to find that Bugsprays twin and some of the manifolds for duals...
You'll probably see quite a difference there.

I wouldn't mess with the internals much (CR) unless you change the cam.
You can easily get carried away flycutting... Keep the CR reasonable and tighten up the deck in a Bus.
(You should find it needs somewhat less timing...)

That 126HP 1600 IIRC was FAR from stock, dry sump, huge valves/cam/headwork/IDAs etc.
(Assuming it's the Austrian rally bug I'm thinking of)

Yup, that is the one and yeh, it had a bunch of trick parts. He didn't say he needed for it to be cheap, just wanted to keep it at 1600ccs

Here's the link I forgot: http://www.rallybugs.com/engtrans.htm

The big thing I was trying to point out is yes, you can make big power from a small engine and keep it NA. Might not be the cheapest way to do it, but it can be done. Plus, just think what technology improvements have come along since 1972.

Piledriver wrote:Welcome to the STF!

My guess would be the manifold/end castings are more of a limiter NA than the heads...

Might want to find that Bugsprays twin and some of the manifolds for duals...
You'll probably see quite a difference there.

I wouldn't mess with the internals much (CR) unless you change the cam.
You can easily get carried away flycutting... Keep the CR reasonable and tighten up the deck in a Bus.
(You should find it needs somewhat less timing...)

That 126HP 1600 IIRC was FAR from stock, dry sump, huge valves/cam/headwork/IDAs etc.
(Assuming it's the Austrian rally bug I'm thinking of)

You think it could handle dual 300 cfm?

Cool article. Makes me wonder what's the most hp someone has made with a 1600 ?
I believer friends turbo s-cab is between 100 and 110

theres a guy here with a turbo 1600 in a buggy that turned some good numbers. I think his build is a sticky. Regardless, I'm interested in seeing where you take this so please keep us posted.

I estimate you'd need to nearly double your engine output to barely break into the 17s; a 16.99 would take about 2½ times the power you have now.
Hate to piss on your cornflakes, but it ain't gonna happen with any NA 1600 engine that'd stand a chance of lasting 6 months in a bus. Even that 126HP IDA-equipped engine would take ~17¼ seconds to push 3300 lbs through the quarter. A stout 1775 or 1915 might have a chance, but what you really want in a bus is stroke - it makes it so much nicer to drive, and a larger-displacement engine (say, 2 liters or so) can give you the power you're after without having to be built with a short fuse.

Pre`72 bus bodies lack any provision for the bellhousing mount. If your stock mounts are in good shape they should work (can you even get urethane mounts for a `68-`71?)...if you're concerned about the next weak link, I predict you'll have problems with the shift linkage inside the nosecone before the mounts.

Wow this is all good info. Much better than the stock nazi's info over on the samba.
I believe that my friends s-cab is only putting out 100 to 110 hp and he is sitting at about 2700 lbs. My bus is about 3030 lbs and I can maybe save another 200 lbs by getting rid of the rear seats and floor mat. I am planning on visiting a dyno soon. We will see soon what I currently get at the wheels. And what the turbo s-cab gets at the wheels.

Every 100lbs you can get out (of a 3,000-3,300 lb vehicle) should be good for ~.22-.24 sec off the quarter-mile time. Losing 200lbs would have the same effect as gaining 3+ HP.

^Truth.

Acceleration combines force and mass over time. If you increase the force or reduce the mass, you increase acceleration, just like no matter what you do with the weight of a vehicle, if you give it enough time and distance, the top speed will be the same because velocity doesn't calculate in mass. If you lose some weight (the car or the driver since they relate), you will accelerate faster. The side benefit is if the weight-loss is done properly, the side benefit can be better handling (think turning as lateral acceleration) but enough on that.

My fun (as in quick) car is an 1985 Mustang GT. Yeh, right up there with an IROC-Z for mental images of mullets and Bon Jovi on the cassette deck. Sorry, no stereo in this one, all the music comes through the dual cats:). Stock these things are low-15s at best. Mine has a mild build (slightly hotter cam, the above exhaust, headers, blueprinted 650DP, mild port job). With the engine done but nothing else, it got into the mid-13s on a cool day. Diet time. Pulled all the AC components, sound insulation, carpet, seats (replaced with lightweight buckets), door panels, etc. Now it is in the high 11s. Want even better?

Look at this:

http://www.badassperformance.com/sdac/newyorker.html

Fun story to read:)

In high school we did somthing similar with a 350 and a chevette. POS but fast.

as for my bus I really don't have much of an interior right now but as I build one I will make sure i keep quick removal in mind.