TheSamba.com :: View topic - bolt on upgrades for stock oval 36hp 1200 engine.

Sun Dec 30, 2007 10:47 pm

When I get my oval in 9 months, once I get to Hawaii, it'll probably have the stock engine in it. While I save up n pay off the loan to get the car I was thinking of ways to make the 36hp a little faster with simple bolt ons. Would ration rockers work with those heads? A 30 or 34 pic stock carb might work also. I’ll be converting it to 12v so a lightened flywheel will make it little faster at accelerating. Can I put a petronix type points in the stock dizzy? Would a 1 1/2" merged exhaust with single quiet pack be too much? I may just go with the abarath 4 tip exhaust to keep it looking old school. Thanks

Mon Dec 31, 2007 12:03 am

Okay first off, You CANNOT convert 36 horse to a 12 volt system, 2Nd you cant run a 34 pict carb on that manifold.

The only way to convert it to 12 volt is to buy a porsche 356 generator, they are the same size.

As for bolt on performance, Dual 28 PCI Old School carbs are good,

Judson Superchargers are good.

Or, an Okrasa would be the best, or just change out the motor.

There isn't alot of bolt on 36 horse stuff.

And, a 64* crank is 6 volt only, lightened flywheel is out of the question, they are only good on High performance applications.

1 1/2 exhaust is a superflous amount of exhaust for that motor.

You can't do any real mods to a 36 horse.

Mon Dec 31, 2007 12:12 am

Quote: You can't do any real mods to a 36 horse.
Sure you can...

How about running it on Alcohol and shoving 20PSI of boost through it..
On top of making it larger than 1600ccs...

Mon Dec 31, 2007 1:49 am

Project_67 wrote: You can't do any real mods to a 36 horse.

Wow :shock: In one bold sweeping statement you've just rendered 14 pages of Samba information...useless :lol:
http://www.thesamba.com/vw/forum/viewtopic.php?t=96565

I think you both have a lot of reading to do. :wink:

Mon Dec 31, 2007 11:34 am

I went to a show in Bakersfield once where a guy was doing custom welded 36hp heads, and welded stroker cranks....you can hot rod a 36hp if you ca find the parts. :wink:

Mon Dec 31, 2007 6:10 pm

yea i read the 36hp post last night, after i put this listing. it has alot of good info. i dont wanna have to split the case. just minor boltons. i was goign to use the 12v porsche generator. ill need 12 starter and fly wheel and coil and i was hoping electronic points would work in the stock dizzy. the ratio rockers will help too. an oil sump and maybe external filter are good ideas too. okrasa abd judson kits cost way too much. the dual 28s would be sweet. wold a 30pic carb fit on the stock manifold? i found a merged 1 3/8ths exhaust btu i wanna keep my heater. thanks

Mon Dec 31, 2007 6:20 pm

kingodirtp3 wrote: wold a 30pic carb fit on the stock manifold? i found a merged 1 3/8ths exhaust btu i wanna keep my heater. thanks

The carb will fit the manifold. Keep in mind that a 1600 header does not fit 1200 engines. The only headers I have seen lately to fit 36hp are these: http://www.thesamba.com/vw/classifieds/detail.php?id=268712

With that in mind adding a header with single qp muffler and a 30 pict-1 carb will probably make a negligible difference in power on an otherwise stock 36hp. I think you would be money ahead to keep your 36hp bone stock and start building on a 1600 based engine.

Tue Jan 01, 2008 2:27 am

thanks. i:ll probably get the 4tip WOB mufler i:ve seen recently. the ratio rockers may help a little bit and electronic ignition, if either of them fit on the stock heads/dizzy. the lightened flywheel that will get put on when i switch it to 12v (porsche gen) will help acceleration. the oil sump and external filter will help with reliability. using a doghouse 36hp fanshroud will stop #3 cyl. from running hot. the bigger carb or even dual carbs with a freeer flowing exhaust will help it some, enough to make me happy till i save up for the type4 engine n tranny swap. i figure anytime you can get the engine to breath better and keep the oil clean n cooler for longer is a good thing. if i can do the dual carbsm ratio rocjers, blue coil with petronix points, 4tip exhaust it should get me to around 45hp and run better n more reliable.

Tue Jan 01, 2008 4:53 am

36hp rockers are unique to the 25/36hp engines. Where have you found ratio rockers for it?

Wed Jan 02, 2008 4:19 pm

i haven't found any, i was asking if soemone new of any.

Wed Jan 02, 2008 6:10 pm

No one makes a 12volt flywheel for a 36hp, you just use the 6volt starter with a 12volt solonoid. You could possibly have the ring gear machined off and install a 12volt ring gear (Berg used to sell) on the 36hp flywheel. As said a 36hp takes a different size(width) exhaust than a 1200 40hp ora 1300-1600 based engine, there are still headers out there for a 36hp, watch the classified, I have several used ones.

Sun Oct 20, 2019 11:45 am

Since it has been a number years I thought to revisit this. Any new parts out there for bolt on 36 horse performance?

The only things I can see would be to run one of the aftermarket 30 PIC carbs (like the '67 stock carb, but manual choke) and replace the pea shooters with open pipes. I don't know if there are any real gains in those changes. I already have a 40 horse box in front of the 36 horse engine, making my gearing about 7% lower than stock.

I'm generally happy with the stock engine, but I have this freeway onramp on my way to work each morning. It is a left hand ramp, short and uphill. I'm finding myself on the freeway in the left lane still only going about 52 mph, trying to get to the right lane quickly because the grade on the freeway means gaining the 8 mph to hit the speed limit will take another 30 seconds.

Sun Oct 20, 2019 8:01 pm

EVfun wrote: Since it has been a number years I thought to revisit this. Any new parts out there for bolt on 36 horse performance?

Wolfsberg West sells dual port heads, a stroker crank, and an 80mm big bore piston and cylinder kit. Speeedwell sells a few parts, aluminum intake manifolds, ratio rockers, and a reproduction of the Pepco supercharger made famous by Dick Beith at Bonneville in the 1960's. Mr Motorhead and Mr Okrasa sell performance parts, those guys, and Blackline Motorsports, and Juan Cole will even build an engine for you.

There's more available for the 36hp platform now, than in the last 30yrs!

Mon Oct 21, 2019 4:34 am

I was thinking more about bolt on parts, in keeping with the original thread. I agree, there are more new internals for upgrading a 36 than there was 25 years ago.

Over at Speedwell pretty much everything is out of stock except the valve covers. A supercharger kit would be a good bolt on upgrade, expensive but a kick in the pants I bet. The ratio rockers are not a bad idea either.

There is the dual carb kit from Riechert tuning, but I never had any luck getting in touch. The feedback here doesn't look promising either.

A dual carb kit, ratio rockers, and an appropriate exhaust would be a pretty nice bolt on package for perhaps 15% more power and something interesting to see at VW events, plus it could be installed in a day without tearing the engine down.

Mon Oct 21, 2019 7:00 am

EVfun wrote: I was thinking more about bolt on parts...

In my experience, 'bolt-on' speed parts don't really do a lot but drain your wallet, and wet your appetite for more 'real performance' :D

Still, your point is well taken. Several friends have taken on the 36hp stone stock challenge, there's a few things a guy can do free up some power, that I've seen first hand make quite a difference.

The first thing I'd do in your position is make sure the engine is well tuned. I've tuned on many cars that have good parts, but one or more things weren't right, leaving as much as 15% power untapped.

I'd want to make sure the valves are set correctly, the engine has good compression, no more than 10% variance across all 4 holes. If it needs a valvejob, it has to come apart. If it's burning a lot of oil, it also has to come apart.

6v systems are susceptible to corroded connections, pitted points too, resulting in a weak spark and erratic timing. Same with older 6v coils, plug wires, cap and rotor, poor connection at the breaker points. I'd want to ensure my entire ignition system was working well, nice blue hot spark. Also the vacuum and mechanical advance function, make sure it's working properly, and you are getting full advance. I'd also mark the pulley at TDC, 5deg advanced, 30deg advanced, so you know where you are and where you've been.

Then the carburetor; float level set correctly, accelerator pump working as it should, tweak the nozzel to squirt near the wall of the venturi (not at the throttle plate). and make sure the throttle shaft doesn't leak air. If it does, have the carb rebushed.

Try leaning out the main jet a little to see if it likes it (you can always change it back). There's a lot of power to be gained/lost in correct jetting. Learn to read plugs or get a wide band O2 sensor, or tune it on a chassis dyno under load with a 4 gas analyzer tailpipe sniffer.

Same with ignition timing, and the wrong octane fuel. Believe it or not, too much octane in a low compression engine will make a lazy, slow reving pig. (often confused, premium fuel does not have any more BTU's in it than regular gasoline) Try burning low octane regular and advancing the timing until it knocks a little pulling a steep grade, then backing off the timing a couple degrees. That alone 'wakes up' many engines.

Mon Oct 21, 2019 9:34 am

Basicly what Tom said.
However, in your case the only suitable way to go is the dual carb way. Yes, the judson is an option, but there is generally too much trouble with them if they cover some miles. And yes the Speedwell is a very good unit, but also rather expensive.
With the dual carb set up. If you want to take most of the guesswork out of it I would recommend you to contact Joe Ruiz or whatshisname, - Bruch something. Both guys have a good deal of experience with the older types of carbs.
The addition of 1,25 rockers will be both good and bad. Good because it will raise the rpm band so it will make more rpm hp. Bad because the lower to midrange torque will suffer. A set of these 1,15 ratio from AA https://aapistons.com/collections/rocker-arms/products/vw-36hp-hi-lift-rockers-1-15-8-pcs would be a good choice (when they get back in stock) because then the bleed off would be minimal and they will still give you 200 - 250 rpm more window on top along with a little more midrange.
Dual 28 PCI´s and the 1,15 rocker arms can give you approx 10 hp extra.

Wed Oct 23, 2019 4:58 pm

My 36 has few miles on an older rebuild, the previous owner drove it just 1000 or so miles a year. I know the valve lash is stable, the idle is smooth and the plugs look nice. One Tim rebuilt my distributor and another Tim rebuilt my carb -- both well known for their work. My distributor has 18 degrees advance max so I have been running 12 initial on pump regular (87 octane.) I usually run the normal E10 because the heat riser is plugged, and a little ethanol really cuts back on the carb ice.

I have not run a compression test. Seeing how I haven't in 20 years on any engine I would let someone local with experience handle it for reliable results. It's a good idea before bolting on performance, but it runs strong and smooth for what it is so not a priority while stock.

I regularly look at the WW Okrasa kit. One idea would be to run that, minus the new heads and with single port manifolds the same height. Surely that could be sold for half the price, considering the heads are by far the most expensive part. I'd buy! One of the older style dual 28PCI kits would be good too, but the throttle blade turns the opposite directions making the throttle linkage less off the shelf.

I know who Joe Ruiz is, Mr. Okrasa. I'm not sure who is the other person you are referring to.

Tue Oct 29, 2019 6:24 am

EVfun wrote: My 36 has few miles on an older rebuild, the previous owner drove it just 1000 or so miles a year. I know the valve lash is stable, the idle is smooth and the plugs look nice. One Tim rebuilt my distributor and another Tim rebuilt my carb -- both well known for their work. My distributor has 18 degrees advance max so I have been running 12 initial on pump regular (87 octane.) I usually run the normal E10 because the heat riser is plugged, and a little ethanol really cuts back on the carb ice.

I have not run a compression test. Seeing how I haven't in 20 years on any engine I would let someone local with experience handle it for reliable results....

Ah, now I have a better idea of where you are at. You should probably get a professional involved, you'd be money ahead. I can recommend the guys at Avery's, https://www.averysaircooled.com/

or if you'd venture across the northern border, Darren Krewenwich (sp) in Vancouver BC, well known for his no-nonsence tuning abilities, engine and cylinder head work, and for helping VW hobbyists in need of good advice.

Or just leave it as is, and have fun driving it.

Thu Oct 31, 2019 2:50 pm

There is always the trusty zenith carb.

Thu Oct 31, 2019 5:30 pm

Is the stock carb the limiter or the intake manifold/heads? I have a 30mm manual choke Solex as well as a larger venturi for my 28pci