I have what I believe to be a standard Pobjoy 1916 in the back of my Beetle. It has a set of 36IDFs feeding it, and it farts through a Vintage Speed exhaust.
On the dyno it has done 71HP at the wheels, which as I understand it, is about where it should be.
Whilst it tootles along very nicely, I'm hoping that there might be a little more potential that can be unlocked, without dropping big money on it. If I could get 90HP - 100HP at the wheels for an investment in parts of less than $2,000 I'd be very happy.
I've got two questions then:
* What's still 'stock' in a Pobjoy base engine?
* What might be a relatively sensible modifications to increase performance?
I think for instance the camshaft and the heads are stock, so that might be a place to start.
Also, whilst electronic ignition might not produce HP gains per se, it should improve drivability?
Thanks for your (helpful) suggestions.
1969 Beetle - June
1974 L Bug - Gwendolyn
2002 Bora V6 4Motion - Anita
BizarreModeratorThe artist formerly known as blue74l
Craig S wrote:I have what I believe to be a standard Pobjoy 1916 in the back of my Beetle. It has a set of 36IDFs feeding it, and it farts through a Vintage Speed exhaust.
On the dyno it has done 71HP at the wheels, which as I understand it, is about where it should be.
Whilst it tootles along very nicely, I'm hoping that there might be a little more potential that can be unlocked, without dropping big money on it. If I could get 90HP - 100HP at the wheels for an investment in parts of less than $2,000 I'd be very happy.
I've got two questions then:
* What's still 'stock' in a Pobjoy base engine?
* What might be a relatively sensible modifications to increase performance?
I think for instance the camshaft and the heads are stock, so that might be a place to start.
Also, whilst electronic ignition might not produce HP gains per se, it should improve drivability?
Thanks for your (helpful) suggestions.
For under $2000 it isnt going to happen.20-30 hp is alot. U will need cam,heads,carbs,exhaust..id keep saving those pennies and just keep enjoing that 71 reliable hp for a bit longer..
Standard unported vw heads with standard sized valves and standard vw single valve springs.......compression set at around 8.5:1 from memory
Standard vw rockers with standard vw pushrods
94 p/b kit
Standard non counter weighted 69mm VW crankshaft with standard VW conrods
Standard full weight flywheel
Standard VW camshaft reground to Tighe camshaft 148a specs with standard VW camgear
30mm oil pump
Should have an anti surge sump fitted.
Carbs are usually Kadrons but yours has 36's
Exhaust is usually 1 3/8 system, but yours has Vintage speed.
The HP you're quoting (71hp) is actually at the high end for a base, with most being around 65-70hp atw.
The bad news for you is that there really isn't much more HP that can be gained from that combo. My old race motor (it died) built by Pobjoy with high compression, street eliminator heads, counterweighted crank, race spec cam, 44 idf webers etc etc had 98.8hp atw....so your target of 90-100hp is not going to happen with your motor.
You can fit 1.25 ratio rockers to that combo which gives it a tad more poke, but as for fitting bigger carbs or a better exhaust, well don't bother as you are running standard sized heads and valves so you will gain no more HP.
The cam in that motor will produce more power with better flowing heads, but as the crank is non counterweighted the problem is that it will not be able to take advantage of the heads and higher revs......so there is no point fitting better heads
Your best option is to start buying parts and find another engine builder,then sell the current motor you have..................to do anything to your current motor combo ( apart from rockers) is a waste of time and money.
Thanks everyone for your time and thoughts, I figured it was probably more of a pipe dream for the budget, but was worth asking.
At present I have three VWs, but because I now catch public transport to work, the amount of kms I do has dropped a LOT. Add on top of that my wife's car and a subaru beater that my son is learning to drive on, the rego, insurance and maintenance is killing me, and one of the five isn't even registered yet.
So I'm thinking it's time to get Gwen "finished" (as much as these things ever are), sell the Bora, and then use the money from the sale to replenish the bank account that has suffered so much and use the remainder to get the 1969 back on the road on 'club' rego. Obviously part of that plan was to give Gwen a little more 'poke', because I will very, very much miss the sweet 2.8 V6 and 6 speed box in the Bora.
Looks like the best idea is to finish everything non-engine related, sell the Bora, get June on the road, save my pennies (which will be easier with one less car) and build something a little more potent in a few years time, and then offset that cost a bit by selling Gwen's current engine. Fast, reliable and cheap: pick two!
Thanks again for the honest advice.
1969 Beetle - June
1974 L Bug - Gwendolyn
2002 Bora V6 4Motion - Anita
Subaru basic ej22 will give you 100hp at rears. If you are mechanically minded it way easy to go down this path and gain power, fuel economy and smoooootthhhness!
Bone wrote:Subaru basic ej22 will give you 100hp at rears. If you are mechanically minded it way easy to go down this path and gain power, fuel economy and smoooootthhhness!
Two problems:
* I'm not very mechanically capable
* I reckon the cost of the conversion once all done is usually higher than what people say
I also still have some deep seated defect, whereby I feel that air-cooled defines the car.
I just found the 2009 thread when Gwen still had the stock 1600 in it, where I started an at times interesting philosophical discussion on conversion vs air-cooled, and nearly 7 years later I still can't bring myself to do it.
I am aware that throughout car culture there is a rich tradition of engine swaps, but I still can't do it. I'd rather go slow.
1969 Beetle - June
1974 L Bug - Gwendolyn
2002 Bora V6 4Motion - Anita
I know, that a very few VW enthusiasts will like it, but we have neat 77 ponnies on stock 1600 / Dave 😁/ which has under 34 PICT 3 a restrictor plate of diameter 29.0 mm...so having a lesser output from overcammed and overcarbied 1915 makes me think a little...
70hp does sound a bit, uhhmmm, well bloody awful really! 😁
I had a 1641 many moons ago in a 750kg '63, and yes I tweaked and adjusted and cajoled the poor little thing into getting quicker, but at the start it had a 34PICT, DP intake, cheap 4-1 and 2" pipe, and mild pocketed heads with a 110-sized cam and 9:1, and bugger me if it didn't run mid-16s and scare the crap out of VN V8s all day.
At the end, after all the tweaking it did high-15s, but the first 150m it would take on damn near anything (including WRXs) on radials without fear.
What did that have I wonder? 45.6HP? Maybe nearly 51.8HP? 😏
We also just recently got a DP 1776 built for the Beetle, and it has stock Pict34 jetted, stock exhaust, big valve heads and 100 cam. I was told it should be good for 70hp at the wheels.
1303Steve wrote:NOS OK for the track but I'm sure Craig wants something streetable
It would certainly make things (illegally) interesting at stop lights, but...... no.
I'm tempted to try 1.25 ratio rockers for the heck of it.
More questions, this time on oil.
At present there is no external oil filter, but based on my reading you'd recommend a full flow external filter?
At what point should I get concerned over oil temp? I've never seen above about 105*C, which is when I'm doing 110 on the freeway, but frankly I've never done more than about 20/30 minutes on the freeway with her before. Would it be worth an external cooler in addition to the doghouse, or is that just introducing more problems.
1969 Beetle - June
1974 L Bug - Gwendolyn
2002 Bora V6 4Motion - Anita
You just need all of your tin installed and well sales.M
Craig S wrote:
1303Steve wrote:NOS OK for the track but I'm sure Craig wants something streetable
It would certainly make things (illegally) interesting at stop lights, but...... no.
I'm tempted to try 1.25 ratio rockers for the heck of it.
More questions, this time on oil.
At present there is no external oil filter, but based on my reading you'd recommend a full flow external filter?
At what point should I get concerned over oil temp? I've never seen above about 105*C, which is when I'm doing 110 on the freeway, but frankly I've never done more than about 20/30 minutes on the freeway with her before. Would it be worth an external cooler in addition to the doghouse, or is that just introducing more problems.
What part of "Subaru" dont people understand . My Ej22 has over 300 on it as still rock solid and Smoootthhh. Only the mower is air cooled these days around here!
Bone wrote:What part of "Subaru" dont people understand . My Ej22 has over 300 on it as still rock solid and Smoootthhh. Only the mower is air cooled these days around here!
Very true, its not all that hard, if you can remove and replace a VW motor on your own your 1/2 way there
