super charging a 2.0 8v tall block

Very interesting reading.

I've got a 1H engine out of a Rallye minus the G-Lader. I was going to go the turbo route and even had a turbo technics manifold and turbo for it but had to sell it unfortunately. I like the idea of keeping it superchargered but not using the G-Lader. What Eaton supercharger would be suitable? Would the M45 be too small? Ideally I'd like to be breaking the 200bhp barrier.

 

M45 would be fine.
It will be much louder at throttle openings than the G lader as a downside.
In terms of performance feel the turbo route is the better option.

 

Not concerned about the noise, it's a track car so it's loud and uncomfortable as it is.

I would still like to turbo it, but I've just bought a flat (hence selling the manifold) and I'm just thinking of the most cost effective way of getting it up and running soon.

I've got uprated injectors and a front mounted intercooler. Other than custom brackets for the supercharger would there be anything else needed? Would the stock ECU from the Rallye be okay?

 

M62 from a merc kompressor

 

You will have to look out for noise limits on tracks.
Yes,
The STD rallye ECU is fine once you can get someone who can recalibrate the spark and fuel tables.

 

Yes you can also use one of these, once you are sure which Mercedes model it came from as not all Merc superchargers are from the M62 family.
Again a study would have to be undertaken to ensure this chioce would match up to expectations, drive feel and engineering.

 

Thanks for this mate, when you say "if only it continued to sustain"..how would you get a more sustained torque curve from the 8v lump, Are there any modifications you can do to the engine to allow this

With regards to the compression drop, is the only reason, the issue of det, so as long as we have good cooling, there should be no reason to look at lowering the compression at 5psi.

Would a different camshaft i.e a mk2 camshaft, a g60 cam, a pipercam aid in the flow rates of the 8v for charged air..

Has anyone played with different pulleys or is there a way to work out the best pulley size for optimum boost whilst staying within the chargers compressor map..

What is it that is limiting the flow past 5000rpm.. is it the inlet manifold.. the exhaust etc..

sorry for all the questions, just trying to work out whats the best way of building a reasonably quick charged engine..

Cheers

Dicky

 

Fitting an acoustic valve works wonders on the noise front
We have done this to Georges.

throttle position also has a massive effect, but it was not a viable option to run his with throttle in front of the charger inlet (but we tried it)

 

Whats an acoustic valve

and why was it not viable to put the throttle in front of the charger??

 

vacuum store if pipework is long makes for a horrible throttle responce..

acoustic valve is a simple usually vacuum switched crude throttle plate which shuts up induction noise. we used it on georges and it made a good 10db(A) reduction on idle and light throttle 'whine'

 

how does it work then.. do you have some pics of one.. cheers...

 

loving this and how neat the install looks.. this is what im aiming at with the eaton.. although judging by the charge temps that you guys are talking about, i think i might have to throw a frontmount in there somewhere...

I have looked into that acoustic valve.. i notice they have them on a clio trophy.. is there only use, lowering the whine..

 

their purpose is to reduce induction noise yes.

The problem we found on t'body on charger inlet, on the setup on Georges, was initially it sucked the silicon hoses flat, as they collapsed under vacuum. We fixed that by inserting wire coils in them, but the throttle responce was horrible...

eg. the length of stored vacuum down the inlet tract was so much so that you could progressively open up the throttle to over 1/4 open before the engine would go off idle, and at the point the stored vacuum was consumed, the revs would fly up massivly..

We ditched the idea and went back to stock position t'body and recirculating dump valve to act as a bypass on idle

 

Yes I agree with this statement but your previous statement petaining to the use of a 20vT engine with different burn rates, combustion design and unknown cylinder pressures based on increased manifold boosting, to justify why it is not required to drop the compression in an 8v wedge shaped combustion design, that is normally N/A, now with a strap on charger is what I took issue with, based on my work with both types of engines.

On an 8v engine using an Eaton M45 supercharger, at 5psig you should be OK on a STD engine pending a good calibration, but on 10psi you will need to reduce the CR if you are to continue optimising torque as MBT will be det limited. They are heavily det limited around 1800-2500rpm when N/A, so with increased cylinder pressures from boosting this would only worsen. I have actually done this back to back. Same done on a 16v (16vs maintain 6psi on the the STD Merc M45) when we were trying to see what we could get away with. All engines use an air to air FMIC.

I agree with by using a DTA standalone on your customer's vehicle should allow you to run the modfied engine close to its optimum. But expect to encounter the same traits in calibration settings that I have stated as you near MBT.

 

you know earlier in the thread you talked of back pressure leading to a level of 10psi as the pressure chokes up.. will this affect the CR then...

Whats MBT...

 

and both turbo and non-turbo 20v engines have identical cylinder head combustion chambers.... which to me confirms what I know.. not an 8v I know.

the point was for the OP, low pressure charging, and 5psi is all the M45 does on stock pulley/stock crank pulley setup, does'nt warrant dropping the compression.

I know the same mk3 e45 charged golf on E38 is what gets referenced to a lot, as he did a lot of write ups during the build, but to me, there are many erros in his spec and approach, which is why I chose not to follow such a flawed path. He has also consummed a few chargers in the process I believe.

Just jumping for the compression plate approach because its goign to be "charged" is not correct as you and I know. the extent of charging is the qualifier as the next sensible question before deciding what to do..(for the benefit of the OP)

I have to say I dont like the E45 charger, and its heat buildup is horrible compared to turbos. If it was a clutched engagement type system, then it would be better. Its always compressing air the engine does'nt want, and bypasses the hotair (well not so hot if the FMIC is working), but the FMIC is constantly hot on its intake be it cruising or ragging.. which is something I just dont like personally. cruising with a turbo car its producing no boost and nothings working hard, but the e45 is still compressing air the engine does'nt want to injest at light throttle, cruising etc..

It has novelty value, but turbo is what I would have done. (but could not have done for the same money)

regards
bill

 

have a read thru some of this...

http://www.ecutek.com/tuning/ignition/

 

as an aside, given your dayjob is engine calibrations, what are your thoughts on the plug failures and headgasket failure my ibiza recently suffered..
maybe best to discuss in the thread here>> http://www.clubgti.com/forum/showthread.php?t=151685&page=14

 

Cheers badger, thats an awesome read.. ive bookmarked it as well...gotta love learning stuff over the net...

1 thing im worried about... is the 8v a 4 window or 1 window distributor?? because i believe the management i got will only work with a tp100 ignition module like that on the mk1 golf and a 4 window distributor..