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sportston · Posted: Wed Jun 21, 2006 10:16 pm Post subject: wanted throttle body

Hi does anyone have a set of throttle bodies from a 16 valve lump?
Does anyone know if they will fit straight onto an 8v lump?

stedee · Alfa 33 Joined: 02 May 2006 Posts: 364 Location: brighouse

yes i do
haha
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sportston · Posted: Thu Jun 22, 2006 12:56 pm Post subject: bully for you!

i'm glad you do. What type? do they have individual flaps? I gather that they won't fit an 8v? In which case, do you have a set similar for an 8v? I don't want to change to carbs but I do want to get more out of the injection system. I'm coming to the conclusion that it may be just as well to get a couple of mini superchargers and use them instead of a single centrifugal one, due to expense. But if I want to fit two units (one per bank), I'll need a different throttle system. I may be able to modify a 16v set.

stedee · Alfa 33 Joined: 02 May 2006 Posts: 364 Location: brighouse

i only have the 16v ones and they are separate `flaps` for each cylinder
do you know you are on about fitting a charger couldnt you fit one on the main inlet of the plenum chamber with a custom pipe - how would you fit 2 if it is injected?
plus what would you do with the pulley to make it fit the belt for the supercharger
i was thinking of fitting one but i didnt want to change the compression and i wanted to do it on the cheap rather than spending 1000
as an alternative i may fit some kind of ram air system
steve
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sportston · Posted: Thu Jun 22, 2006 5:40 pm Post subject: would need this

You'd need to make a custom pulley that lowers the standard ratio in order not to overboost the engine. The problem with fitting just one charger is the diverting the air from the charger to each side of the engine. Normally this would not provide a problem , you'd just put a great big scoop/bulge on the bonnet to make room. I don't want a great big scoop. It would draw too much attention. I don't want the plod or local thieves eyeing up my vehicle every time I park or drive it. So you could make a modified plenum but it would mean channelling the air through 2 very acute angles, which doesn't seem good engineering practice. It would also be very interesting to have a system that could easily have the boost increased by a change of pulley without making the chargers spin too fast, thus shortening their lifespan and reliability.... The engine might not last very long though... How do you do it with fuel injection you asked? Fit a FSE fuel regulator (already done to mine).
Make a T in the MAP sensor pipe and join it to both sides of the engine to average it all out. Then get the ECU re-mapped ideally.
Can it be done for less than a grand? I'm not sure, but possibly. I'll let you know when I've done it.
And one more answer:- Why use two mini chargers? because they are cheap and readily available second hand in as new condition on ebay for a fraction of the cost of a new one elsewhere. I'm falling out of love with the idea of using a single centrifugal one due to the cost and availabilty. But I haven't made up my mind yet....
Watch this space!

sportston · Posted: Fri Jun 23, 2006 10:22 pm Post subject: BUT

You've given me an idea. I wonder if I can use one larger unit upside down? and move the alternator to one side, then make up 4 semi-circular pipes for a plenum....hhmmm. Needs more thought....

sportston · Posted: Sun Jun 25, 2006 7:41 pm Post subject: Changed mind

I think I've changed my mind. I don't want the throttle bodies now. I've decided to go for an upside down twin screw charger. So now I need to get a fuel injection manifold for an 8v ie that I can experiment on and make fit to the charger. Does anyone have one?

stedee · Alfa 33 Joined: 02 May 2006 Posts: 364 Location: brighouse

hello me again
i have got one for a 16v(you might have guessed)i think they are the same, i have been told that the manifold would equalise the pressure of the forced air to each cylinder - i was wonderind could you put it on backwards and then the inlet side would face the front and make it easier to connect the supercharger with a bit of modified pipe

will you send me photos of the work in progress so i can have a look and see how hard it is
cheers steve
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stedee · Alfa 33 Joined: 02 May 2006 Posts: 364 Location: brighouse

call me thick but how does the pulley effect the compression ratio?
i thought the ratio could only be altered by conrods or the thickness of the piston or thicker headgaskets
you can put 8v pistons into a 16v and that lowers the compression
steve
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sportston · Posted: Sun Jun 25, 2006 7:56 pm Post subject: not the engine ya dime bar!

It won't lower the engine compression ratio!
What I meant was; lower the ratio of pressure made by the supercharger in comparison to the engine revs.

stedee · Alfa 33 Joined: 02 May 2006 Posts: 364 Location: brighouse

yeah yhats ok then i thought i was totally missing the point once again
my hearing is sh**e can i blame that
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