Which Direction? Itbs Or Supercharging

[rallyeash 155]

My NA 205 is over 300hp/tonne

[welshpug 1,622]

S

 

Even on a low boost setup (250 bhp ish) you're looking at well over 300bhp/ton and plenty of torque to go with it.

 

You underestimate how heavy a gti6 lump with all the gubbins bolted to it weighs, even before bolting the SC stuff on Spikys car was 835 KG, that's 308/ton at 258 bhp, hardly "well over"

[Matt180 31]

Yeah I suppose theres a fair bit of difference with the EW being all alloy, mine comes in at 817kg 1/4 of a tank and I was going on that!.

 

 

All things considered it still has more power to weight than a GT3 rs and that's on a low boost "low cost" setup. Im pushing mine to the limits of my s/c and just shy of 460bhp/ton....still not spent a lot for those kind of figures!!

[welshpug 1,622]

I bet it doesn't stop and turn like a GT3 though

[allye 530 3 Cars]

I wouldn't mind betting Matt's stops a fair bit quicker than a 911.

[Matt180 31]

I'd give it a good go I can certainly stop but no high powered FWD car will pull out of a corner like RWD. I had a 10 lap battle with an instructor in a S/C Atom at Donnington last year. I eventually got past after carrying far more speed on the straights and into the corners, just cant get on the power as soon as he could!.

 

The battle ended with me breaking my gearbox He came over and had a good chat with me in the pits and showed a lot of interest in the car, he even took me out for a few laps in the Atom to cheer me up They are a awesome bit of kit, no drama at all. Couldn't get my head around the fact we were going the same pace and yet it was so smooth, I guess that's the difference between a proper chassis and a 25 year old French bean can!

Edited December 19, 2013 by Matt180

[rallyeash 155]

They are a awesome bit of kit, no drama at all couldn't get my head around the fact we were going the same pace and yet it was so smooth, I guess that's the difference between a proper chassis and a 25 year old French bean can!

A lot of that will be the Atom has proper focused suspension geometry rather than a Compromised cheaply built French hatch. (By Peugeot, not meaning this personal to your build) It's a large cost to get the roll centre, suspension pick up points correct and eliminate flex from the chassis and subframe.

 

My mates 205 which has had the full Colin Satchell suspension setup, subframe, customer wishbones, worked 406 hubs, bump steer sorted, rear coil overs etc is a completely different car to be in compared to mine which runs track focused parts but retaining a GTI subframe, 309 front running gear and a Convential 205 beam albeit with big torsion bars and arb.

Can compare this to your experience with the Atom. I appreciate the Rwd and fwd difference though

 

Yours sounds like a beast with that kinda power though! Would love to see it at a track day some time

Edited December 19, 2013 by rallyeash

[Gman 29]

I used to have an audi s3 and hated the delayed power delivery. However, I was under the impression that the Lynx SC suffered from no "elastic band" type power delivery and throttle response was similar to a standard engine. Or am I completely wrong on this?

 

I love the adjustability of the car on the throttle as it is, and bodies may be the way to go if a SC will spoil this.

 

Sandy - I will PM you about ITB options

[Matt180 31]

rallyash- I agree on the rear coilovers, that alone has turned mine into a completely different car!.

 

 

Gman- I'm not sure where you have heard that? it certainly doesn't sound like the typical Rotrex delivery!. I haven't been out in a lynx powered car, but its all pretty much the same!. The only difference with the lynx kit is that the TB is on the inlet of the S/C which I don't like the idea of. That shouldn't affect power delivery though. Mine makes linear power all the way to 7900rpm

Edited December 19, 2013 by Matt180

[Batfink 201]

A correctly sized throttlebody for the supercharged car will help responsiveness massively. The standard GTI6 one is too big for 'small power' 250-300bhp. More like for 450bhp.

Now you will never get the same response to a tb'ed car but its not really much different to a n/a single throttle body. As you are driving the car hard I never once thought I didnt like the response from an eaton! The car was also standard compression. I guess theres some differences in pickup when a car runs lower than normal compression in how the power is delivered but the car felt standard in how it responded, but simply much much faster.

I do love the noise from throttlebodies over any other sound though, lumpy cams and bodies just make a car for me. Its old school character. I'd actually say I'd rather have less power and a better noise. If I was chasing over 220bhp I think i'd go supercharged. DIY is so much cheaper. Top end n/a engines are too much for the likes of me on my wage.

Edited December 19, 2013 by Batfink

[welshpug 1,622]

The lynx kits use a restrictor ring, even on the 400 bhp high boost kits

 

Though its not purely about the boost figure, its about how much air going in, was chatting to a friend that works at a GTR specialist, and they only run around 1.1 bar for 700+ bhp on standard engines, but rather different turbo and exhaust specs.

Edited December 19, 2013 by welshpug

[rallyeash 155]

I didn't realise your car was on rear coilovers Matt... ill have to have a browse of a build thread :-)

[Matt180 31]

Yeah have a nosey, it needs updating actually but for some reason Im struggling to upload photos!?

 

 

That's something else I have in my favour, mine is high compression at 11.1 so helps with the response.

[cheesegrater 43 1 Cars]

Looking at the power curves you'll see an Eaton come on alot sooner than a rotrex. Ill happily take you out in mine and I'm sure if you speak nicely to Justin he'll do the same. Albeit his is an Mi rather than a GTI6.

[petert 551]

Is it just my impression of the dyno sheet, or is the Lynx SC very flat under 3000? It doesn't appear to have much more than a strong NA engine.

[allanallen 528 2 Cars]

Is it just my impression of the dyno sheet, or is the Lynx SC very flat under 3000? It doesn't appear to have much more than a strong NA engine.

That's how they are, even the 'high boost' are sedate low down, It means they're kind on the drivetrain i guess and as far as the low boost goes it's probably a lot kinder on the standard engines.

 

I'd like to see a graph of yours Matt if there is one? I imagine yours is much nicer with the throttle body downstream of the charger.

[Matt180 31]

It also depends a lot on how they are geared. Mine is wrong, i need a smaller pulley to bring the boost in quicker and i wouldn't have to rev the nuts off it as much!

 

[Harni 6]

That's how they are, even the 'high boost' are sedate low down, It means they're kind on the drivetrain i guess and as far as the low boost goes it's probably a lot kinder on the standard engines.

 

I'd like to see a graph of yours Matt if there is one? I imagine yours is much nicer with the throttle body downstream of the charger.

 

This. Even a Super high boost one which is 450hp is only (i say only!) 300lb/ft

[markw 1]

I have a Tb`d GTi6 (ish) engine in my car and it is amazing, makes just under 240hp

at just under 8k, sounds awesome, but big power costs a fortune, I built it for sprints and hills and has been very successful in its first year, BUT I have to say can be a bit "tiring" who wants to drive round at 7k+ revs all day on a track day yes, but from 40mph on the public road to overtake slower car, my mates 200hp 8v turbo is quicker, I will fly past him at about 70 though!!

 

I am a big fan of the 8v turbo and my next road car will be engine`d this way.

[Gman 29]

Thanks for all the help and advice on this. I have decided to go down the lynx sc route.

 

All I need now is to find a reasonably priced second hand sc kit!

[dcc 855]

Spikys...

[Gman 29]

But overpriced in my opinion given that a lot of much newer kits go for around the 2k mark and that was when they were still relatively sought after

[Spiky 37]

Also, don't forget if you buy a 306 setup you have to do all the mods and make pipes up like I have to get it to for, where as my setup is for a 205

 

Food for thought

[dcc 855]

it is a bolt on 205 gti kit, that comes with engine and everything you need? He's even mounted the intercooler! I suppose you can only lead a horse to water...

[Gman 29]

I do appreciate that it has most of the kit needed. It does however need the inlet shortening to fit a standard 205 bonnet and a power steering pipe made up for the relocation bracket.

 

Spiky, is yours currently running the cossie inter cooler or the larger one? I.e. Are the pipes make to fit the cooler behind the front grill?