Supercharged Stock 1600 DP

[T-34]

Been following MarioVelotta's thread on his Microsquirted 1600 and he suggested that I post my own build thread up here.

I recently got an early bay back on the road and foolishly forgot how damn slow a stock 1600 was in these things. Having just rebuilt the engine and not having the budget to build another bigger engine I decided that I needed to make some improvements in the power department and decided that forced induction was the way to go. Whilst I've actually been bouncing the idea around of turbocharging a stock 1600 for the past few years, I was inspired by some of the vintage speed guys and decided that I would add a supercharger to this one.

My build is based around a bone stock 1600 DP with an AMR 500 supercharger. My plan is to hopefully eventually get this to the stage where I can sell them as a kit.

As I have already posted a build thread elsewhere I will do a bit of cut and paste jobbie and copy the info here.

[T-34]

Taken from my blog over at VDubber.com... http://www.vdubber.com/blogs/entry/supe ... ght-part-1

A buddy of mine has been collecting parts and researching adding an AMR supercharger on his 36hp powered oval. Inspired by the 36hp medusa oval he's opted to use an AMR 300 blower on his project. After doing a bit of research of my own, I decided that an AMR500 blower would probably work reasonably well on a stock 1600 engine.



My plan for the conversion is to use the stock 1600 with no other modifications. Eventually I intend to change out the headers to something that will flow a little better but for the initial test I want to see what kind of power gains can be had by simply bolting on a supercharger. For this I will need to get some baseline readings, so at some point I will need to get the bus on a rolling road.



I plan to set the supercharger up in draw through configuration. Originally I wanted to use the stock PICT34 carby as I have only just had it rebuilt but soon realised that I do not have the height to fit it in the bus without resorting to mounting the supercharger in some weird location. The best configuration seems to be to use a side-draft type carburettor. I did a bit of a search for 2" SU's but they are not so common over here in Australia, even EBay did not turn up too much. I did consider robbing one of the SU's off of the Jaguar but decided against it. Instead I decided to use the good ole tuners favourite a Dellorto DHLA40. As luck would have it a sole DHLA40 was ripe for the picking on EBay, so I crossed it off of the wanted list.



I also stumbled across a local guy here in Adelaide. He runs a Jap car business and imports AMR superchargers, he was able to supply me with a pair of blank flanges for the AMR500 along with a vee type pulley and a blank flange for a Weber IDA (Same pattern as Dellorto DHLA - I hope!) Now I have everything I need to be able to make up my own inlet and carby manifolds. The new pulley ratio should give me about 7 or 8 psi when run from the stock diameter crank pulley. This is not an exact mathematically calculated figure but should be in the ball park. There are simply too many variables to consider to be able to calculate it with any accuracy. I figure that it should be a good starting point and if I need to increase / decrease from there I can then look at running a smaller crank pulley for the supercharger.



My plans for the drive setup are to use a longer belt to run both the generator (to be replaced with an alternator) and the supercharger. I will use a tensioner pulley to help keep everything in check and stop the belt from jumping. If for some reason I do need to reduce the supercharger speed I will opt to fit a power pulley and a Porsche alternator pulley. This will have the effect of providing a lower ratio drive for the supercharger whilst maintaining a stock fan speed for optimum cooling. If I need a higher ratio drive for the blower I will likely have to look at running a separate pulley and belt for it.

I plan to mount the blower to a custom made mounting that will attach to the stock filler tower mounting bolts. This may also attach to the fuel pump mounting bolts as well. I will likely get rid of the mechanical fuel pump and use an electric one. This is mostly because of space constraints but also to help prevent fuel starvation.

At this stage I am also trying to keep the costs to a minimum. At the moment I am waiting for the Dellorto to arrive. Once that is here I will look to making the mounting bracket and manifolds. There are a few other things that I need to sort out before I can install it but for the most part there is relatively little to do.

If everything works out okay, I might look at manufacturing the parts to sell as a DIY kit. Both with and without the AMR500.

[T-34]

As a starting point I went and took the bus to the local dyno to get some baseline power figures.

In stock configuration with an SVDA and a 34 PICT/4 the bus was making a massive 39.8 HP (about 51 at the flywheel) WOOT!

Since then I have been busy designing and building the prototype. I've made up a jig to cut the make the with manifolds and built the initial supercharger stand. At present the kit is basically finished apart from one or two small details.

Today I dropped the engine out of the bus to fix up an issue with the bulkhead tin and swap out the generator for an alternator I also plan to fit the supercharger. My initial idea to use a stock exhaust for the first dyno test has gone out of the window and I have opted to use a vintage speed exhaust instead. I figured that if people are going through the trouble of fitting a supercharger they would likely not be using a stock exhaust. If I get some time down the track I might swap it back but at the moment I need to get some miles on the engine as I'm due to go on a road trip in a few weeks.

Hmmnnnnn

For some reason this forum does not rescale the images so I cannot post my images. I know someone will say rescale them and upload them to photobucket or somewhere, but to be honest I can't be bothered. Being a web developer it really is a very simple matter for the forum admins to improve image handing and rescale the images on the fly.

The images can be viewed here - http://www.vdubber.com/photos/album?gro ... bumid=1109

[andy198712]

that looks like its fits really well!

[T-34]

Thanks Andy.

Originally I wanted to fit the stock 34PICT/4 on top of the charger but there simply isn't a lot of headroom over an upright engine in an early bus so this forced me to turn the charger by 90 degrees and use a side draft. I've tried to keep it as compact as possible.

I need to get the body back on my bug so that I can take a look to see if it will fit. My guess is that the Dellorto will be too large for the decklid to close without standoffs but I will have to wait and see. Would be good if one setup would fit both bus and bug. If the Dellorto ends up being too big I will look to use a single barrel carburettor instead.

One limiting factor is the alternator. if this was made for cars with generators only then it could be made to sit a lot lower.

[T-34]

Incidentally - I will be making up a kit for a 36 horse - a buddy of mine wants one for his '58 so when he gets the engine back together I will be using it to develop a prototype for a 36hp version.

Vintage speed with a decent supercharger

[MarioVelotta]

This will be really cool! You should fit a throttle body on the side so it can be tested with EFI as well. It would be a snap to switch out the factory end castings to EFI as well. I like the simplicity.

[T-34]

Been busy today finishing things off. Working through the last few items on the TODO list and generally getting things to a state when I can start to install it in my bus. I disassembled everything and gave it a coat of magic black paint ready for assembly, and here it is - the fruits of my labours for the past couple of months. Kit #1. This is obviously just the prototype and the finished product will look a bit different (and have better quality welding) but it's along the lines of what I want to put together. A turn key kit with everything you need. I just couldn't resist taking a photo of everything together - it almost looks like the real deal



I also dropped the engine out of the bus ready for the transformation. It's still suffering from my trip to Speedweek - 2 hours driving over unsealed roads means that red dust gets EVERYWHERE - even inside stuff that was inside the cupboards!! Fortunately the stock oil bath air cleaner actually works really well and there was not a trace of dust in the air filter or inlet - testament indeed!!



With everything cleaned down I stripped the engine down to fit the supercharger. It was interesting to see how an end user might fit the kit. I was originally hoping that it could be done without removing the engine but unfortunately it looks to be too much of a PITA to remove the stock manifold without removing the fan shroud, which itself is a PITA with the engine in the car. It would be possible to get it out without having to take off the fan shroud by cutting the right hand heat riser off but this might asking a bit much. So unfortunately it looks like an engine out job to fit it.

With the engine out of my bus I also addressed a few other issue such as the bulkhead tin. AFAIK early 1600 busses were fitted with single port engines without dog house coolers. This means that the tin does not have the hole for the doghouse cooler tin to exit through. When I fitted the engine I opted to ignore this but as it did run hot on a couple of occasions (cruising on a 41 degree day) I opted to cut and shut the tin with a late beetle tin.







I've also got a fan assisted oil cooler to fit. The case is already full flowed and running an external filter, I will extend the oil hoses and add in the cooler once the engine is back in the bus.

So with the bulkhead tin fixed and the generator swapped out for an alternator (the stock generator simply isn't man enough to drive my fridge) I started to install everything. I hit one or two small snags - the fuel pump case studs are longer on this engine and the fly cutting on the top case is a little different and so fouled the stand a little. Once addressed the rest of the supercharger went on pretty easily. One thing that took a little time - simply because it is uber-fiddly, was getting the pulley aligned. I opted to make the stand so that the supercharger can be aligned using washers behind the fixing bolts to pack the supercharger in / out as required, I've done this so that any variation in engine setups can be accommodated. The only issue is with sausage fingers like mine trying to get washers on a bolt that I cannot reach is a little hard. Still - I'm glad I found out how hard this is as I can address this in the fitting instructions.

And this is about where I got to...





Everything is mostly fitted up, I just need to limit the advance on the dizzy, fit the exhaust and see if she runs. I also have to trim a bit of the carby gasket back as it interferes with the throttle linkage before I put the engine back in the bus (and vacuum out the engine bay).

I will initially run the engine out of the bus so that I can easily address any issues that might arise. Once I am happy I then need to get the bus back on the dyno to get it set up properly. I'm pretty sure that the carbs will be lean but don't have a functioning AR meter to test with (got a couple of lambdas but no gauges). The carby is from an Alfa and would have been part of a pair on a 1800 / 2 litre engine.

I'm also betting that I will need to swap out the venturis as it only has 30's fitted. I figure 34's or possibly 36's would be needed but I'm far from an expert in these matters. Here's the rest of the carb info:

The jets are as follows:

13.0 mains
7772.11 emulsion tubes
180 air correction
58 idle jets

If anyone has any insight into the carb set up it'd be greatly appreciated. Only information that I can find about sizing Dellortos relates to twins and not singles. It would be good to get it in the ball park before taking it to the dyno as they do not usually deal with Dells and I figure the nearer I can get it the less dyno time it will cost me.


Mick.

[helowrench]

Very nicely done

[Zander]

Frickin cool! I love the look of a blower

[andy198712]

This will be really cool! You should fit a throttle body on the side so it can be tested with EFI as well. It would be a snap to switch out the factory end castings to EFI as well. I like the simplicity.

does the charger need fuel through it to cool?

[gearheadgreg]

In my experience, most blowers do not need any fuel through them to cool. Roots blowers like this one can seal better with a small amount of fluid and the evaporative cooling can help the intake charge temps.

[MarioVelotta]

How much for the intake and charger less the the carby and manifold? I would be real interested in trying this with EFI over here

[T-34]

The charger has teflon coated vanes and doesn't need an additional lubrication. They work okay in draw through too. Some blowers don't as the fuel can lift / react with the coating.

@Mario. I will have to finalise costs and work out a price. Leave it with me and I will get back to you.

Mick.

[T-34]

So. Spent today fitting the engine into the bus. Had a bunch of shits and bits to fix up like fixing up my dizzy, rewiring for the alternator, fitting a new exhaust, adding the electric fuel pump, running new fuel lines, cleaning red dust from everything. In fact it took most of the day just getting everything to the stage where I could fit the engine.



I opted to drill and tap my dizzy so that I can dial in the overall advance. Much better than locking it out completely



Annoyingly I also had to fabricate a throttle adjuster / stop as I had failed to realise the DHLA carbs do not have an air bypass circuit and so require a throttle stop to be able to set the idle.

Got to say. This is the worst engine install I've done. Normally I can get it in pretty easy (said the actress to the bishop ) but this time no matter what I did the engine simply did not want to line up. I must have struggled for half an hour trying to align everything before I finally managed to get the thing home. I recon it's the damn stoopid sump extension that I have fitted - it was in the parts bin left over from a previous project so it got fitted to the bus. The issue is that the jack doesn't sit centrally so the engine doesn't sit right on the jack, which makes fitting the engine a bit of a PITA. Fortunately I picked up some spare flywheels last week so I will make myself up and adaptor for my jack so that the engine sits nice and flat.

By far the most annoying issue was that my 5 minute dash to the local motor shop to pick up some more fuel hose ended up with me stranded for an hour as the damn stoopid immobilizer on the Range Rover decided to play up. Eventually I manged to get the thing started but the remote control has decided take a holiday. Arrrrgh - just what I need - 2 cars off the road. Think It's time to put some rego on the scooter.

With the bus engine finally fitted I checked everything over and found that the banjo fitting to the carby had a hole in it. This was easily remedied by tapping the hole and fitting an appropriately sized bolt. However, when it came time to fire her up she would not start. I checked the spark - which was okay. Checked that there was fuel getting supplied to the carby, even checked that fuel was getting through the carby into the stacks. The engine would occasionally catch, but not start. This led me to think that the issue was not enough fuel getting through.

So I removed the carby and stripped it down. One can of carby cleaner later I have one cleaned carburettor. I will wait until tomorrow to see if this has fixed my issue.

Thinking aloud - my main concern is that the jets are simply too small / lean to work in this configuration. I had originally assumed that even with incorrect jets the engine would still start, but having never had a blown engine before I'm not 100% sure how the blower will react to incorrect carburetion. (sp?). I'm happy to drill the jets out to get the thing running, but only if I am pretty sure that this is what the issue is.

I will do a bit of reading to see what I can figure out before tomorrow, but it's 12:30, I stink of petrol and carby cleaner and I figure that I probably should get some sleep.

Actually - on a positive note. One thing I was a little concerned about was the belt tracking. My biggest fear was that it would throw the belt. Well, I'm happy to say that the belt stayed put. Yay! one positive to take from today!!