120 replies to this topic

[mini25]

yeah but going back to the orig question, would it not be better to get 200BHP with 2 turbos, as u would get power at low revs or is this not poss

[Sprocket]

No mate. Not on a five port small cc engine. The T3 is man enough and you can get hybrid ones built to overcome these issues, you just need a big wallet.

[Leonard]

minisprocket, surely the 16valve head on this engine proves that the head has released all this power? i know it also uses different cams as you cant use the 5port ones, but as i understand, its the head that gaves the extra flow?

minisprocket, surely with this engine its the 16valve head thats freed up the power?

[Sprocket]

I did say the 300+bhp was debated and did not say that it a 16valve head would not produce any more power.

Comparing highly tuned normaly aspirated race engine of 1480cc with a five port head ( which has nothing below 4000rpm) in the region of 140bhp?? against a 1293cc turbo which is driveble all the way through the revs producing 225bhp. The five port head is not as much a limiting factor as you are suggesting, when turbo charging.

Granted putting a 16valve head on the a series realeases power but that is not realy required on forced induction. remember that the gearbox and clutch reliability are already stretched at 225bhp.

Even with a 16valve normaly aspirated 1380 engine it only gives 180bhp in race tune so the five port 1293 turbo still comes out tops

When talking about the head being the limiting factor, then this would be more so the case on a normaly aspirated engine and this forum, funnily enough is called 'Turbo Charged'

[Grant]

watch this a-series turbo 224BHP

http://videos.street...45B43BE719A.htm

[Oldskoolbaby]

The Japanees 16V Delta Mini has 210+ bhp in N/A form. I reckon that with a cros flow head 300 bhp will be acheivable. But as everybody says, the gearbox will just not beable to take it. Maybe using an inline A series mated to a gearbox from an other manufacturer will solve this. Saying that though. I wouldn't want 300 Bhp through the front wheels. Id rather mount it in thie back.

[Miniwilliams]

mini25 that's a very good point you make, as after all most of the top skylines run 2 smaller turbos to make the power more usable, so why not on an A series.

[Wil_h]

Unless you have staged turbos, two turbos will make little differance to power delivery. Mainly because the two smaller turbos only get half the exhaust energy/volume so they won't really spin up any quicker.

Twin turbos are usually used because for packaging, 'V' engines for instance.

I know that the later Subaru Legacy turbos used a stage twin turbo setup, I assume that this is what the Skylines use too.

[Grant]

just watched that video again, does every turbo flame??? and the two buttons on the gear nob does anyone know what they do??.

thanks

[Turbo Nick]

my mini certainly doesn't flame like that....i think he's got something special that he wont tell anyone about

If i remeber right when the car was in miniworld the two buttons are for different boost settings.

[Jimmyarm]

How about putting two turbo's a series turbo engines end to end like they do in the Astons' with the ford V6's (I think they both drive through the same gear box).

Straight 8 A series turbo, I want one !

[Miniwilliams]

I see your point Wil, but a skyline is a straight 6 engine. as is the supra. just seems funny that from standard they have 2 turbos. it must be cheaper for the factory to add just one, so 2 must be different in some way.

[miniboo]

the reason why they have twin turbo's on those cars is because the engine is so big that to have a singlew turbo it would be massive and would cause enormous lag. therefore they have have two twin stage turbos low boost and a high boost one i believe.

[Bigbudders]

I think both the turbos are the same size, they just use smaller ones so they spin up quicker, reducing the lag effect. That was the idea with the porsche turbo anyway, don't know much about them Japenese beasties, but i suspect it would be the same reason.

[Jimmyarm]

The Skylines have two smaller turbos to bring the boost on earlier for improved acceleration.

A common mod is to replace the two with one big beastie to give better top end power, my GF's brother has an Rx7 with one big turbo on (replacing the two smaller ones originally on it). Its pushing out about 420bhp

He's doing laps around the ring of low 8's and recently won the RWD class at silverstone, beating a Porsche GT3 ! Best thing is he drove his car there and back and the 2 competitors behind him had theirs trailered there. I want his car ! lol