Rb25de (supercharged) Project

[Louїє]

nice build (:

[r33_racer]

Ok so not much good! It made a best of 330ish rwhp, but its been pulled to 300rwhp until I can sort things out. Driveablity is shit house as the bypass valve is too sensitive and its too on/off when it comes onto boost. The powerfc also isnt good enough to try and help tune around this sudden change in boost, so when it does come onto boost it goes really rich really fast and it doesnt like it so it stutters, backfires pops and farts before it comes good and inorder to get it go good straight off you really just gotta jam the throttle open and then it goes like a rocket.

Now the good bit is the down low to midrange is just fantastic! I found out if you accidentally stab the throttle from slow speed and it manages to get past the silly afr's and revs out cleanly it just breaks traction all over the place. Had a few hairy moments on the trip home lol. Its impressive for such low hp!

The downside is the noise it makes is just stupid! Its so fricken loud. I got way more attention then Im comfortable with on the way home. So I need to try and figure out a way to reduce the noise. Farks me how though...

The heat thats generated also is quite high. Compounded by the fact the extractors run right next to and over the top of the intake. So the radiating heat isnt doing it any favours. The outlet and intake pipe get so hot you cant touch them. So im going to look at some water/meth injection to feed into the intake to hopefully reduce the intake/outlet temps.

So I still have alot of work to do to get it upto scratch! But im happy that it didnt blow up and nothing major went wrong!

Edited July 20, 2010 by r33_racer

[TiTAN]

map based ECU for the next tune?

have you thought about making up a heat shield for between the extractors and the charger/pipes? or wraping the intake pipe with fibreglass wrap?

[Duncan]

lol complaining about exactly what you were hoping for

for the noise....remember that we are all used to a dirty big turbo damping the noise from the motor....supercharger has no such restriction in the exhaust and you have to consider much more muffling than in a turbo setup.

I know plenty of turbo cars running no mufflers and "acceptable" noise levels on the track....none of which have anything on even a tiny, non-turbo motor. It was really driven home to me when I pitted next to a (real) mini with side pipes....it was way louder than my race car

[r33_racer]

Yeh I will most likely get a Vipec.

At the moment there isnt really much room to make a heat shield. When I modify the intake tract, it will give me more room between them so I can then do just that. I think number 2 primary is like 10mm away from the intake. Not very well designed unfortunately lol. Good thing is there is always round 2!

[Duncan]

why not just get a link? same hardware as vipec but cheaper.

[r33_racer]

lol complaining about exactly what you were hoping for

for the noise....remember that we are all used to a dirty big turbo damping the noise from the motor....supercharger has no such restriction in the exhaust and you have to consider much more muffling than in a turbo setup.

I know plenty of turbo cars running no mufflers and "acceptable" noise levels on the track....none of which have anything on even a tiny, non-turbo motor. It was really driven home to me when I pitted next to a (real) mini with side pipes....it was way louder than my race car

Yeh I know what you mean Dunc. But the exhaust isnt too bad, though it could do with another muffler or resonator, lol perhaps a cat to atleast keep it legal to some degree. Its the supercharger noise thats the issue. The induction noise is loud, the discharge and whirring noise is way over the top. Its about ten times louder then what I was honestly expecting.

[r33_racer]

Didnt consider a Link. But will look into it!

[Duncan]

ahh that side! need to box the intake, and consider the resonators like the standard intake system has. nfi how you would guess the right resonator volumes though.

the march is damn loud on the intake side when the SC is running too....but it turns off over 5k.

[Rolls]

The induction noise is loud, the discharge and whirring noise is way over the top. Its about ten times louder then what I was honestly expecting.

Maybe remove the pod and put the air box back, and consider putting some sound deadening around the unit?

[r33_racer]

Yeh I will definitely have to look at all those options! Cheers for the ideas.

The sound deadening was something I was considering also Rolls. Around the p.side guard and probably under the bonnet. If it only reduces about 10% of the noise it would have helped a shitload! About the airbox, im not sure Id be able to fit that back in. Would probably have to fabricate one...

[r33_racer]

Dunc does that charger turn off via a clutch pulley system of somesort?

[dazmo]

Splurge out and get a good ECU mate MoTec or Autronic. The Vipec is overrated and not really that great an ecu the logging is shit a doesnt work properly and they have trouble acuratley reading a crank trigger.

As Duncan said if you are going to get one you would be better off with a link as that is really all a vipec is although slightly Autronicized and the link is cheaper.

I understand that budget is a big factor for a lot of people (personally i think the ECU is the most important part of any build so cant understand why people would not get the best available). Also consider that the vipec has been on the market for only one year or so where as MoTec and to a slightly lesser extent Autronic have been at the forefront of ECU tech for over 20 years hence being the controll ECU for many motorsport catagories and the prefered choice of a major percentage of some of the most successful race teams the world over and there is a much larger choice of tuner for either of these ECU's. Another point to consider is that a lot of workshops will sell you whatever product has the best profit margin in it for them and not what is neccesarily the best product.

I know of several people that have coverted to a Vipec only to then find out they are not all they are cracked up to be and have since gone to a MoTec or Autronic and achieved a much better end result and one of these guys was one of the Vipecs biggest fans.

[r33_racer]

Yeh I heard Paul has gone to a motec lol.

Well the powerfc was in the car when I got it. So its just stayed in there since. We run a SM4 in our race car, but I just cant afford to put an autronic or motec in my road car. Link or vipec perhaps or something else around that level. I do dream about motecs though!

[dazmo]

Fair call might be best of with an extra loom for the road car and just use the autronic and swap between the road and race car and just upload wichever apropriate map. worth considering as is pretty hard to drive two cars at once. At least that way you can then just buy yourself another sm4 when the budget allows. By the time you spend the coin on a vipec link you will be a little more than half way to a new sm4 anyway.

[Duncan]

Dunc does that charger turn off via a clutch pulley system of somesort?

yeah it has an electric clutch on the front because the turbo takes over above 5000rpm. just like an ait con compressor clutch

[MBS206]

Yeh I heard Paul has gone to a motec lol.

Well the powerfc was in the car when I got it. So its just stayed in there since. We run a SM4 in our race car, but I just cant afford to put an autronic or motec in my road car. Link or vipec perhaps or something else around that level. I do dream about motecs though!

Look at the adaptronic then, either the e420c or e1280s.

[TiTAN]

Fair call might be best of with an extra loom for the road car and just use the autronic and swap between the road and race car and just upload wichever apropriate map. worth considering as is pretty hard to drive two cars at once. At least that way you can then just buy yourself another sm4 when the budget allows. By the time you spend the coin on a vipec link you will be a little more than half way to a new sm4 anyway.

he isnt the only one driving the cars, his dad drives the race car too doesnt he?

trying to compare an ecu that costs twice as much (or more in the motecs case) as the link/vipec isnt exactly fair, for the money on a street car they are a very capable ecu.

one thing thats confusing me a little, why does he need an extra expensive ecu with uber awesome logging features on a street car? you dont exactly drive around and check the logs after every trip to the shops

[zebra]

I do, lol

[Rowdy]

I do, lol

+1 lol

oh well if youve got it you may as well use it