I think you'l find that to hit 100% VE at a given rpm, (on a race motor) will have more to do with the hermholtz effect. (Tuned intake runner length) I've read that during R&D jaguar actually acheived MORE THAN 100% VE (At one engine speed) using really long runners.

Blower is up and running. I don't have the manifolds made up yet, but the blower itself is mounted with the belts working correctly, pumping air around the engine bay. It sounds farking awesome,
EDIT: but made a mess:

nasty mess


Quote:

theyre just generalised numbers, from the same book, a 4 valve head is 88% VE, so that Ferrari head that you're running would have to be at least 130% minimum


kululadotgroen-

Your're right about it being way underdriven, that is deliberate. the 4AGZE runs an SC12 on a 1600 engine, this is a SC14 on a 1500, looking for low boost (4-6 psi) as a testing ground for further mods.

Quote:

I have just had a thought- is your engine in your car? If not (and its not too much hassle) would you be able to pull the crank pulley off for a comparo with a A series? I was looking at the crank pulley size on a 86 corolla on the weekend, but didn't have enough time to pull it off and see if it could be easily adapted to fit an A series. The one on the N/A 4A-(k?) series engine I looked at was more like 120mm diameter.

This setup needs a decent front pulley- the one I have made has produced a couple of nasty resonant patches in the rev range (surprise, surprise), so when I upgrade to higher boost I will get somthing made up properly.

Still working on some suspension stuff, so engine is not in yet I'll pull it of tonight and measure it up for you ie. crank hole size, key depth and such.

The pulley is a double one, with the front pulley being a lot smaller than the rear one. The rear one drives the SC and the waterpump, and the front one drives the alternator and powersteering. The front one should be around the 120mm size, which adds up with your measurement of the N/A one.

Another question, are you going to get rid of that nasty belt driven fan and add an electric fan, 3kw right there you know...

thanks for that- I'm thinking of either using the 4-A pulley if that is possible or getting the pulley taken off at a machine shop and welded on to my A15 one.

plastic fan is long gone, I am running two thermo fans, but I need a thermostat that opens earlier cos it is pretty damn hot here in summer & the thermo's end up running pretty much non stop to keep it cool. My temp guage also wobbles all over the shop, so I need to sort that out as well.

A few updates:

There are a couple of different options for mounting the carby for a draw through system-

the first would possibly be best if you were going for a draw through only setup, which would mean mounting the blower the correct way up:



..... yeah, ok.

corner

offset

But for the setup I have the carb stays in an almost standard position, just forward about 10-15cm, which would potentially allow you to cover the whole lot with a large, round aircleaner (preferably offset to the rear) and keep things looking reasonably standard.
moved forward

rotated 90 deg

You have to make a blanking plate for the emissions:

plate

the flanges require a far bit of patience. despite the thickness, the flange still warped a bit when I welded it.

10mm Steel beam used for for manifold flanges

outlet manifold

And on a side note, always make sure you use the right gasket- this one was matched to the bottom of the carby rather than the shape of the manifold. the vacuum has torn the section between the two carby throats uot and sucked the gasket through my engine. Would have been interesting to know if it burned up or went straight through.carby gasket

I have just got round to finishing the manifolds- turned out to be more work than I had hoped, but that's always the way with these things....... especially when you don't have the right tools for porting. Struggling to find hoses in 2.25" diameter for a decent price (and not bright blue) will have to wait till businesses open up in the new year.

I am about to lose regular internet access, but I will do my best to post up results and a dyno sheet within the next month.

realy should use silicon hose. I tried an inferior (But still fuel proof) hose on mine. There was a massive backfire, and It dropped two clyinders. plus the sound of charger blowing out through the blown hose. I thought I'd blown the motor.

She's a runner, and performing beyond expectations.

I had to go with bright blue silicon hose ( expenseive ####e too) and being the dumbass I sometimes am, used a 90 degree silicaon hose to attach the transfer pipe to the inlet manifold. Under normal driving conditions the manifold vac crushes the hose, & then it pops out again on boost. laughed my arse off when I first started it up and saw this thing breathingwhenever I hit the thottle. Seems to run ok regardless.

Runs up to just over 5psi. and goes pretty damn well- seat of the pants suggest its up by 20-30%.

Not all plain sailing though.
The first and biggest problem I have is that the carby does not have an accelerator pump jet for the secondary throttle. this means that it runs lean and pings on transition to the secondary. I am not sure how to overcome this- if there is another model of 32/36 that does run a secondary pump jet or I have to work out another solution, like hooking the throttles up so that they are synchronous.

The next problem is that I run out of spark at about 5500-6000. I need to close the plugs up a bit more (currently 0.7mm from 0.9 stock) but I also have a whole lot of cr@p that sources its power from the positive coil terminal (O2 sensor, clutch for blower etc) so finding a more appropriate source for these may help the situation a bit.

(does anyone know if this affects spark?)

the last problem seems to be fuel supply. After a first, second third run, as it was winding out in third the AFR meter suddenly went from 11.8 to 17 under full throttle, accompanied by a massive dive in the power. My guess is that the stock fuel pump couldnt keep up, and the blower sucked the carby bowl dry. A good way of blowing up an engine.

Anyways, in between these problems it is running strong with a bucketload of torque (compared to before) and boost coming on from around 2000rpm. oddly enough, it actually sounds smoother than it did as a N/A motor.