Squig's Project; WIP

[Squig]

Thought the time had come to put down my progress in this WIP regarding the Uber Cavalier/Calibra Project... as yet I'm undecided on the bodyshell to use, my reasons are I need the 4x4 floorpan or at least something capable of running IRS at the back, which means a diff and at least the 4x4 rear drivetrain setup. I do want it to be a Cavalier, but I will absolutely NOT break a running turbo, gsi or 8v 4x4 to get what I want, there are simply too few left as it is. If I must a Cally will be used, however if I find a shell someone else has stripped when I come to need one then I will do what I want.

Now a quick warning to those who like quick start to finish WIPs or WIPs with huge numbers of pictures, this isn't one of those, nor will it be one of those. I wish to post a large amount of information others can learn from as I have so far, and a goodly amount is maths based I'm afraid, as well as touching on airflow re supercharger applications and converting a high compression NA engine into a FI low compression engine, which I will point out at the start is not easy and expensive. Which leads me to the reason this will take time, the expense and wanting things to be over engineered.

This project has to date taken 5 years owning to plan changes, finding suitable parts and learning what can work and what doesn't, either because there is an simpler way or for common-sense reasons. I have owned 2 engines intended for this project, a c25xe and a x30xe (the later being the engine to be used) and originally intended an Astra mk2 to be the shell running 4x4 through an F28 (since installed in the daily driver Cavalier v6), then decided on the Cav/Cally and recently realised the intended torque output would probably ruin the F28 in short order, hence the intentions now stand to a RWD 3.0v6 Supercharged Cavalier*.

...

*The project will be refered to as a Cavalier until the time comes to shell it.

[TurboDan]

This thread is useless without pictures!

[Squig]

not my fault you can't read anyway there will be pictures but this isn't being a glorified gallery

[TurboDan]

I think you should buy an old cav turbo shell and make it RWD as in turn the engine round and do it that way, would be well cool!

[Squig]

being done...

[Squig]

Engine & Internals;

• Standard X30XE block,
  Ported and mild polished heads with narrowed stem valves,
  Standard cams,
  Vernier pulleys,
  C20LET Mahle low comp pistons,
  Forged 4340 con-rods,
  C25XE pattern crank (unsure of this as yet as not checked fitment, but would be hoping for a crank capable of coping with 1200bhp, equating to 400bhp reliably),
  Eaton M90 supercharger.

As yet this is the intended parts list to convert the high comp 3 litre into a 8.5:1 CR FI engine... the idea is that the c25xe crank gives a reduced stroke (from 86mm to 79mm) which reduces the overall swept volume from approx 3 litres to approx 2.8 litres, I am aware that the turbo pistons will have an effect on the volume however the CR has been calculated without the head cc or the piston cc being accounted for, I can't see this having a massive impact and any effect it does have will allow more supercharger pressure. Speaking of which, supercharger maths is confusing... and I need to have it explained... more on that later...

[Squig]

Well it would appear the maths I've needed for some time was published in issue 47 of PPC and Ferkle had the issue open in the bog, which I saw when dropping logs .

The formula to calculate boost in supercharging is; (((SCCC / (EngCC / 2)) x PR x 14.7) - 14.7) - ((VO / 10) x 0.05)

• SCCC - Air flow in cc per rev of the supercharger,
  EngCC - Engine cc,
  PR - Pulley ratio,
  VO - Valve overlap.

And according to the maths I should be running 16psi of boost...

[Mort]

Have you seen this? - http://www.vauxhallownersnetwork.co.uk/ ... p?t=198634

Is this the sort of shell you are after for your project? You won't be first in line for it by the looks of it, but you might get lucky...

[Squig]

cheers buddy unfortunatley no where to store it in the meantime...

[humbucker]

Just bought an M90 supercharger on ebay for £130.84 inc delivery!!! assuming no hitches...

sound familiar?! that's you in 2006! let the party begin!

[Squig]

Could have been... there were hitches and hence some serious research has been going on, where was that from as I cant log into astra mk2 any more?

[humbucker]

from mig:

http://www.migweb.co.uk/forums/engines- ... lease.html

[Squig]

cheers buddy... yikes, I've learned since then

[Squig]

Right a little news here, kinda to promote another thread.... I have 5 LET pistons and need a 6th so please give me shout if you have a spare reusable one somewhere.

anyway...

Some side by sides of the newer LET and older 30XE's



and a quick guide to Mahle pistons from Vauxsport;

In the inside of every MAHLE - Piston you can find a casting number.
This number consists out of two numbers, then a letter and again two numbers.
From the letter you can find out of what kind the piston is:

D... Duotherm piston
F... Squeeze-cast piston
KB... Ferrotherm piston
L... Solid skirt piston
P... Forged piston
V... Auto-/Hydrothermik piston/
Auto-/Hydrothermatik piston

For example: A piston with the casting number 96 P 26 would be a forged piston.

Mit freundlichen Grüßen / Kind Regards

Claudia Richter
MAHLE Aftermarket GmbH

[humbucker]

are they the exact same size? i did read that you could do a direct replacement as the dimensions were the same but wondered about the tops, to change compression. also, while i think of it, for your project are you fitting steel conrods?

[Squig]

not sure... need to use the existing rod dimensions at the very least as the big end bore is too small in the LET.

So the plan, once one more LET piston is obtained, is to rebuild using new piston rings and standard rods for the moment then to start checking dimensions of the omega box I've got for comparison, then I can find out whether a remote SC installation is needed or whether I have room to top mount it.
Either way needs to be longitudinal to get the room... but the more I think about it the more I lean towards a cally build (it has the soul of a cav at least)... with a cav front as I can get more room, height wise, and hopefully not need to build a bulge.

[humbucker]

have you seen this?!

http://www.migweb.co.uk/forums/projects ... t-end.html

[Squig]

that's what gave me the idea

[Squig]

well ladies and gents, I'm afraid bad news today... all bar one of the pistons I've acquired are FUBAR'd... and although new replacements can be obtained, they are £100 a pop.

So this project is being shelved while I start saving.

On a plus point I now know where I can have the rod and crank nitride hardened for £20/rod and £200/crankshaft... I've been advised as well the chap who does it has a racing clientèle who run his nitride prepared gear in 600+bhp racing engines (see Excel engineering on our recommended map)...

So some good news but a hell of a blow with it.

[humbucker]

sad news man but worth it if you stick with the plan and shelve it for a while... will definitely be one to watch out for... and hey, that lottery win is just around the corner... right?!

[Squig]

to be brutally honest mate I'm half tempted to get rid altogether and just dump the 3.0 in the cav and be done... feeling that low over the whole thing...

[Envoy CDX]

to be brutally honest mate I'm half tempted to get rid altogether and just dump the 3.0 in the cav and be done... feeling that low over the whole thing...

Shelve it while you save as you say. Drop the 3litre in and it gets you a bit of play time

[humbucker]

you feel deflated now but you'll forever think 'what if' if you dont go for it in the long run. then again i appreciate the costs arent to be ignored.

[Envoy CDX]

you feel deflated now but you'll forever think 'what if' if you dont go for it in the long run. then again i appreciate the costs arent to be ignored.

It's usually cost that stops most plans

[Squig]

I need sponsorship....


Feeling better today... cheers guys for the comments