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Wed Oct 21, 2020 4:34 pm

Hey all, just trying to get the best / correct carb and distributor combo for a 1776 in an early bug. Only real mod will be a 2280 cam. I want to keep it stock looking so i'm guessing 34 pict carb with 034 or 205 vacuum distributor? Thanks!

Thu Oct 22, 2020 5:41 pm

Why so big and little on the carb? You doing experiments outback?

Thu Oct 22, 2020 6:11 pm

Years ago i built a 1776 with a 34PICT-3 for a friend... it ran better than I expected.

Yes. 034 vacuum/mechanical is my choice.

Thu Oct 22, 2020 7:47 pm

Glenn wrote: Years ago i built a 1776 with a 34PICT-3 for a friend... it ran better than I expected.

Yes. 034 vacuum/mechanical is my choice.

My friend had his 1973 1600cc DP built to an 1835cc DP and used his stock 1973 carb and distributor, fine.

Thu Oct 22, 2020 7:50 pm

I never understood why people go bigger in cc's, but don't up the carb size. A stock 1600cc is so under carb'd already.. You missing out on about 15hp..

Thu Oct 22, 2020 8:33 pm

craigman wrote: I never understood why people go bigger in cc's, but don't up the carb size. A stock 1600cc is so under carb'd already.. You missing out on about 15hp..
one time i tried this as well.
never again would i curse any "perfomance" engine with a single stock slowlex carb. if you're going to take the time to actually make this work right, then why not use a better carb?

Fri Oct 23, 2020 4:52 am

Once again.
Your bad results are because you think in dual carb tuning, and many often rely on either the stock air cleaner or a crappy crome air cleaner, which now, 40 years later still does not work properly on a Solex. - And, some people want simplicity over dual carbs.
Yes you can get more power out of the engine with dual carbs, but many don´t. In fact I have more than once heard stories from my customers that they have outrun similar dual carbed engines uphills. In a straight line there is of course no substitute for a freer breathing engine.
Dan, if you can find it down south, you would want a VW 043-905-205 or the same with an "L" suffix. Set timing to 10 degrees at idle, adjust max timing and youre in business.

Fri Oct 23, 2020 5:06 am

craigman wrote: I never understood why people go bigger in cc's, but don't up the carb size. A stock 1600cc is so under carb'd already.. You missing out on about 15hp..
Not everyone that drives a VW is a top ender! Some of us are content with excellent torque and good midrange power. I've had both singles and duals and can appreciate the simplicity, drivability and low maintenance of the singles.

Fri Oct 23, 2020 6:10 am

I agree. Up to about 80hp from a 1776 with a 34 Solex is not to be sniffed at, especially if compared to a stock 50hp 1600.

After a ver short warm-up my 1776 with that single Solex runs like a modern fuel injected car. I can accelerate smoothly in third from 1200 RPM and rev it till 5000. It is a so much better engine than stock in my early bay window bus. Plus it looks stock and is as simple as stock to run and maintain. Cheaper than dual carbs. Spark plugs easy to get to, no syncing required, etc.

Yes, I could get more power out of it with dual carbs but to me it's pretty much perfect the way it is.

I've had dual carbs in beetles before and they are perfect for cars with emphasis on performance. For everyday usability I really like my modified 34 on my 1776.

Fri Oct 23, 2020 4:08 pm

Thanks heaps for all the replies so far. Alstrup, what kind of air cleaner do you suggest? Also, what size venturi can you go up to before you start losing the vacuum signal for the distributor? Thanks!

Fri Oct 23, 2020 6:38 pm

You can gut the stock air cleaner, but leave about 60-70 mm of the inside "stack" Then take a K&N style filter to put inside. dependant on the actual year of the air cleaner housing you may need to "help" the intake a little.
Also, when doing it this way you will have to run the breather into fresh air, because it is almost not possible to get it on the right side of the filter. If you are creative its possible though :-)

On a mild 1776 I would go 28 mm. No more. This hardly influences the vacum, so no problems there.

Sat Oct 24, 2020 9:09 am

My 1776 Street Sleeper combo with 8.5 to 1 CR, ported and polished 37.5 x 32 valved heads, a W90 cam and a rejetted 34 pict 3 carb puts out 85hp and 75ft/lbs of torque and FEELS like it has dual carbs.

There is nothing wrong with running a single carb in a performance set up as long as it's done correctly. Sure, you are leaving HP and torque on the table but getting every last horse and every last ft/lb of torque is not everyone's end goal.

Sat Oct 24, 2020 9:29 am

HI Roy,

Whilst I agree with you in principle I find 85 hp very optimistic for the combo you describe. On the other hand the the 75 ft/lb torque number you give is less than a stock 1600...

Had you said 75 horses and about a 100 ft/lbs. of torque. with a power peak at just above 4000 RPM I would have no problem believing you.

To be sure: I'm not calling you a liar. I know you built more engines than most. Maybe you mixed up some numbers or the dyno was off?

I have been following closely achievable Solex single carb performance from various guys experimenting and specializing in the field and I know 85hp are possible from a 1776. But hardly with a 34 PICT with stock venturi and the W90 cam, I don't think.

Stefan

Sat Oct 24, 2020 9:38 am

It depends on which correction factor is used. Also static versus sweep - Something we typically tend to forget when rating hp etc.

Sat Oct 24, 2020 9:42 am

StefansBus wrote: HI Roy,

Whilst I agree with you in principle I find 85 hp very optimistic for the combo you describe. On the other hand the the 75 ft/lb torque number you give is less than a stock 1600...

Had you said 75 horses and about a 100 ft/lbs. of torque. with a power peak at just above 4000 RPM I would have no problem believing you.

To be sure: I'm not calling you a liar. I know you built more engines than most. Maybe you mixed up some numbers or the dyno was off?

I have been following closely achievable Solex single carb performance from various guys experimenting and specializing in the field and I know 85hp are possible from a 1776. But hardly with a 34 PICT with stock venturi and the W90 cam, I don't think.

Stefan

Sorry, doing two things at once. 75hp and 85ft/lbs of torque

Sat Oct 24, 2020 10:20 am

[email protected] wrote: StefansBus wrote: HI Roy,

Whilst I agree with you in principle I find 85 hp very optimistic for the combo you describe. On the other hand the the 75 ft/lb torque number you give is less than a stock 1600...

Had you said 75 horses and about a 100 ft/lbs. of torque. with a power peak at just above 4000 RPM I would have no problem believing you.

To be sure: I'm not calling you a liar. I know you built more engines than most. Maybe you mixed up some numbers or the dyno was off?

I have been following closely achievable Solex single carb performance from various guys experimenting and specializing in the field and I know 85hp are possible from a 1776. But hardly with a 34 PICT with stock venturi and the W90 cam, I don't think.

Stefan

Sorry, doing two things at once. 75hp and 85ft/lbs of torque

Ah, thanks. that hp number now makes sense. torque is still low-ish but that may be due to larger than stock intake valves?

I have standard size valves, the CB 2239, 1.25 rockers on the intake, CB center section, a bit more compression than your combo and 105 ft/lbs. of torque.

Sat Oct 24, 2020 11:24 am

StefansBus wrote: [email protected] wrote: StefansBus wrote: HI Roy,

Whilst I agree with you in principle I find 85 hp very optimistic for the combo you describe. On the other hand the the 75 ft/lb torque number you give is less than a stock 1600...

Had you said 75 horses and about a 100 ft/lbs. of torque. with a power peak at just above 4000 RPM I would have no problem believing you.

To be sure: I'm not calling you a liar. I know you built more engines than most. Maybe you mixed up some numbers or the dyno was off?

I have been following closely achievable Solex single carb performance from various guys experimenting and specializing in the field and I know 85hp are possible from a 1776. But hardly with a 34 PICT with stock venturi and the W90 cam, I don't think.

Stefan

Sorry, doing two things at once. 75hp and 85ft/lbs of torque

Ah, thanks. that hp number now makes sense. torque is still low-ish but that may be due to larger than stock intake valves?

I have standard size valves, the CB 2239, 1.25 rockers on the intake, CB center section, a bit more compression than your combo and 105 ft/lbs. of torque.

Those numbers are with the stock pea shooter exhaust. Running a 1 3/8" header system will bump both number up 7-12 points, depending on what exhaust is used.

Sat Oct 24, 2020 1:14 pm

Makes sense. Stock exhaust is (too) restrictive for pretty much anything above stock. I wouldn't run one on such an engine not only for performance reasons but also to keep head temps down.

Sun Oct 25, 2020 3:48 am

Thanks again for the replies. What exhaust setup is best to use with the 1776, single 34 pict, 2280 cheater setup please? Thanks!

Sun Oct 25, 2020 4:49 am

DANP85 wrote: Thanks again for the replies. What exhaust setup is best to use with the 1776, single 34 pict, 2280 cheater setup please? Thanks!

Anything with equal lengths "headers" and less back pressure than stock. Some vintage speed models are quite alright, apparently.