412 replies to this topic

[stevevx220]

Jon Have you any idea how much the new charger will cost? Steve

[Jon]

Hi Steve, Harmut (Hitec) and I have had many conversations about this and we are trying very hard to keep the costs down so that we can both supply and fit the conversion for a target price of £4500 inc vat. this way it will be £1000 less than the Delta conversion, whilst offering the benifit of a charge cooler system and more power in the stage 1 and of coarse then with the stage 2. The stage 2 work starts this coming week. Regards Jon

[VIX]

I'm starting to get allot of stick from Mark, friends and now customers ! about its lack of use, they may have a point 18months old and 1202 miles is a bit embarrassing

If you want someone to put some miles on it just say the word!

On the earlier post about reliability, I wouldn't be too bothered about shortened engine life provided the vehicle was reliable in the meantime.

[Jon]

On the earlier post about reliability, I wouldn't be too bothered about shortened engine life provided the vehicle was reliable in the meantime.

I'm conviced that this will be a very reliable conversion, as we (Hitec and ourselfs) had no internal engine problems with the old delta conversion and this was running without charge cooler etc. With the new conversion, the major componants i.e supercharger inlet manifold etc because off their OE use will have OE durability.

I for one cannot wait, I've got to give Marks turbo a run for its money...

[stevevx220]

How much will the systems weigh? (v1 & v2) Steve

[Jon]

How much will the systems weigh? (v1 & v2)

Steve

Hi Steve its a good question as I want to work out the power to weight ratio. We should have this info very soon, we think at the moment its about 21 kilos. The drive shaft on the new unit is lighter as it is cast as part of the super charger housing.
In theory the stage 2 will be marginally lighter as the supercharger pulley is a smaller one (for more boost) machined from alloy, which may save .5 of a kilo, hey it all counts

[SPLAM]

Jon you only do 66 miles a month, my offer still stands.

[Foxy]

IIRC Damon was saying that he was getting under 15mpg following his SC conversion...is this what you would expect, Jon?

[Jon]

Its worse than that it did 1158 miles in the first 4 months and has not been outside since!! the other milage has just been streching its legs inside on the dyno to keep everything lubricated etc I do have a little excuse, as it has no seats at the moment !!!!

[SPLAM]

I do have a little excuse, as it has no seats at the moment !!!!

Feeble excuse.

As Foxy says MPG would be good to know.

[Jon]

IIRC Damon was saying that he was getting under 15mpg following his SC conversion...is this what you would expect, Jon?

No this is not normal, as Maggs is getting much more than this. The problem we found on Damons was a weak recirk valve hose which was callapsing causing the manifold to get momentary boost on cruise. This meant that the computor would react but pulsing in fuel on the additional injectors and thus over fuelling the car at part throttle . The new conversion has the dump valve bulit into the super charger inlet on a butterfly which then feeds directly into the inlet manifold so no more callapsing pipe.
Therefore your cruise economy will be as standard. Full throttle will depend on how much you are enjoying yourself.

[SPLAM]

what has hitec said about the head on the 2,2 engine?.

i know some of the engineers at saab, that is developing the turboengine aswell as the sc (not really official ).

one of the biggest concernes for boosting a 2.2 is the weak combustionchambers in the head.
the roofs are too thin and the lostfoam-casting isn´t helping

i got 2 (evolution3) cylinderheads from saab that has 80% thicker roofs and a upgraded kokill-casting.
they are good for >450hp and very stable at high cylinderpressures.

Jon,

A little *bump* of Dudes question. Any ideas?


Oh also Will the rev limits still be the same?


Sorry for all the questions.

[Jon]

Dude is quite right the 2.0 LM 850 turbo unit has got a better grade of casting. This is due in most part to the GM durabilty test, all engines have to go through this test. which is 200 hours flat out at different RPM's, i.e pulling a concrete caravan up a hill. So when they are talking about failures it is at very extreme loads and heat build up. The VXR engine only just passed this at 220 bhp by the skin of its teeth The MK5 Astra VXR turbo engine has had major work to pass at 230 bhp. Now I'm not saying this to start scaring VXT owners etc, but the point is they do this worst case scenario test so they know the engine will last a damm long time, seviced poorly and driven without any mechanical sympathy. Most manfacturers will recognise what the police say in that even the most aggressive drivers can only drive flat out 10% of the time, before they come to an obstuction, be it other traffic, a junction etc. So we would not get the opertunity to drive at full load for hours on end. Which is why we do not see Z20LET engine failing left right and centre at 250+ bhp. Further more we are lucky in that our cars weigh little more than a bag of crisps, so it is allot harder for us to subject them to these extreme loads The GM 2.2 drag engine that had its first failures at 284bhp this was rods I dont think the head was changed untill over 330 bhp. One other point to note the 2.0 supercharged engine was developed down the road by Lotus, indeed a friend of mine did some of dyno build work and mapping. This 2.0 unit was used as it was already in existance built for the turbo application, and runs quite a high compresion ratio. So some of this development problems will have been more to do with the turbo as they run hotter than the supercharger. With the 2.2 conversion we have dropped the compression far lower than GM for safety and durability. Thanks for staying with me through all that. If you made it this far here is the answer to the second question Yes the rev limit will remain the same. Right I'm off for a beer

[SPLAM]

Right I'm off for a beer

And deservedly so to.


Thankyou Jon.

[stevevx220]

we have dropped the compression far lower than GM for safety and durability.

How has the drop in compression been achieved Jon?

[Ricky2772]

Most manfacturers will recognise what the police say in that even the most aggressive drivers can only drive flat out 10% of the time, before they come to an obstuction, be it other traffic, a junction etc.

I must be mad then...
just drove back home from ski-resort on my A6 on winters.........
it was an 1,5 hours long worth of 3-lanes hwy....
flat-out at 220kmh AT ALL TIME ...with few slow-downs in between...
wifey coud not believe I was home that fast...with her along, it takes usually 2+ hours.....
...aaaaaah..some fun here and there in life....

[Jon]

we have dropped the compression far lower than GM for safety and durability.

How has the drop in compression been achieved Jon?

The compression ratio has been lowered again by a lazer cut stainless steel plate and 2 gaskets. This seems to be a very commom way to do this, HKS do the same thing, we have been doing this on all our turbo conversion since 1988 in fact the more European tuners I talk to the more common it seems.

[SPLAM]

So the plate is sandwiched between the two gaskets i take it?

[Jon]

So the plate is sandwiched between the two gaskets i take it?

Yes Sam, exactly that.

[SPLAM]

How far off if you know, will the SC be ready for you to start fitting?