Tarmac Rallying Perpetual Thread

[tk80]

i just keep coming back to the turbos and sump (dry sump) question.

Haven't seen too many of the cars at drive bathurst at targa...that's all.

[sav man]

N1 Turbos are laggy, but they can handle a tonne of boost. Just means you have to rev the engine (We ran ours to 8500rpm)

As I've said before, once you move the pickup, and gate the std sump it'll do the job easily.

You don't see many Targa cars on the circuit, because most of the cars don't have a racing class to fit into.

[Marlin]

Bathurst isn't a sustained high revs track, and I would tend to do only say five laps at a time rather than go round and round and bloody round, that's what will kill it.

[sav man]

As far as high revs go, Mt Arrowsmith would have a lot more sustained high revs than Bathurst.

[Marlin]

Yeah I'd tend to agree. I also believe that if a car can last Targa, it can last just about anywhere if driven sensibly.

[sav man]

When the Targa class in tassie got to run at the V8 Supercars, the only cars that couldn't handle the 15 lap races (local races are 5-7 laps) were the circuit cars. The cars that compete in Targa just kept going and going.

[Snowman]

There is no doubt in my mind now that a PROPERLY set-up GT-R on Targa N1's is pretty much as good as anything for a circuit car (bar the superlap type specs).

My car would easily run sub 1.20's at Sandown now - and there sure ain't many cars running sub 1.20 at Sandown. I used to be convinced you needed around 400awkw's to achieve that but we now have several cars closer to 300 running those times.

Looking at history the Gibson cars were doing Bathurst in 2.15's and Sandown in 1.16's on slicks. So if my car can do 1.18's on R Comps at Sandown I'd say sub 2.20's on slicks would not be an issue - if the driver is up to it.

[PHaT MR30]

You were there Roy.... you saw it didn't you?

He might have been there, but didn't see much, too busy watching Porn in snowy's toerag

[Roy]

If only I could have had more me time in the bushes. Not sure I saw it Spent a lot of time looking at the Rick Shaw RX7 that was for sale on the back of the truck :0

[Marlin]

There is no doubt in my mind now that a PROPERLY set-up GT-R on Targa N1's is pretty much as good as anything for a circuit car (bar the superlap type specs).

My car would easily run sub 1.20's at Sandown now - and there sure ain't many cars running sub 1.20 at Sandown. I used to be convinced you needed around 400awkw's to achieve that but we now have several cars closer to 300 running those times.

Looking at history the Gibson cars were doing Bathurst in 2.15's and Sandown in 1.16's on slicks. So if my car can do 1.18's on R Comps at Sandown I'd say sub 2.20's on slicks would not be an issue - if the driver is up to it.

Completely agree Snowy. You'll remember the Dutton I was at with you, I ran the White 34 around Sandown in a 1:20.1 from memory, and I'd never seen the track and did four laps. I think a reasonably fast Tugga car is pretty fast anywhere, even my dirty 32 is one of the faster cars of it's ilk around Lakeside.

[Snowman]

Yep - it's like sav suggested N1's are laggy.

They are only laggy if you run bigger cams chasing top end speed/power. My car was full boost by 3,000rpm and had 300awkw's by 4,500rpm. Hardly laggy. Consequently we were shifting before 8,000rpm too.

(but I run stock cams)

Good response and GOOD handling - and these cars will be quick around most tracks.

[tk80]

tomei 260 9.15 cams are pretty mild (what i've got).....are you saying even they are too big for good response?

from memory mark berry's 32 had the same cams with n1's in the early days and that thing was an animal down low. Mind you i think he had about 28psi running through it.

[Marlin]

Yep, and changed turbos every time you looked at it due to wear.

[tk80]

Yep, and changed turbos every time you looked at it due to wear.

translation please

[PHaT MR30]

translation please

Frequently replaced the turbos due to wear from running high boost

[Snowman]

The biggest issue with bigger cams I found is the off throttle response. Off the throttle into a corner and back on the throttle there is a lag in response compared to standard cams.

Back in the early Dutton days - I had those cams and -5's. My car made 380awkw's. And I was able to run 1.21's at Sandown. We changed back to standard cams - which according to the dyno was WORSE through the middle - and ran 1.19's. But you could massively feel the difference in back on throttle response which is where the time came from. Even bigger gains were had a places like Winton where there was more benefit to throttle response.

I have had more tubro / cam combinations than I care to consider on an RB26 engine - but if I was building a new one from scratch (which is basically what I did last year) I would build one with standard cams and N1's and know I could run around all day long and beat 99% of cars out there. (And the ones I couldn't beat would probably be 1 lap wonders).

And yeah - Mark was running straight 110 race fuel. I've always run 98RON from the petrol station.

[Marlin]

Frequently replaced the turbos due to wear from running high boost

Once again Timmy keeps me on the straight an narrow

[R31Nismoid]

Yep - it's like sav suggested N1's are laggy.

They are only laggy if you run bigger cams chasing top end speed/power. My car was full boost by 3,000rpm and had 300awkw's by 4,500rpm. Hardly laggy. Consequently we were shifting before 8,000rpm too.

(but I run stock cams)

Good response and GOOD handling - and these cars will be quick around most tracks.

I think he is talking R33/R32 N1 turbos though, sav - correct me if i am wrong.

So if he is, 33/32 N1 items are ridiculously laggy. Think worse than -5 response, for the same power as R34 N1 turbos.

It's not a pretty picture as nothing happens below 4500rpm with the older variants and hence you need to ring balls to get anywhere

[sav man]

yep R33 N1's, full boost at 5500rpm. dad ran 25psi through them in Targa 2010, and we checked them after the event, and they are still like new. cams were stockers n1's.

anyone with R34 N1's who winges needs a kick in the pants.

[Marlin]

Yeah I never had issues with the 34 N1's, and it was always good for a good clutch kick