t70

[D1 WTF]

so single tubby, is it good?  is it the way to go?  i did love the speed of the twin as it does kick in so quickly and just kkep accelerating!

[Ed_RX7]

Had a conversation with Geff about popping the engine out to have the ports extended a tad so that might well be a winter project...

yes a man after my own heart!!!:chat

[nurspec]

Singles are better for top end power, TO4R  keeped hauling arse hard at high end revs ,compared with twins,depends also what driving you want to do,
In town racing stick with twins/Small single, drifting medium to smallish single,drag - biggest single with seroius porting,

Does that sound right..

so single tubby, is it good?  is it the way to go?  i did love the speed of the twin as it does kick in so quickly and just kkep accelerating!

[A7NTY]

Had a conversation with Geff about popping the engine out to have the ports extended a tad so that might well be a winter project...

Make him do you a 1/2 bridge port, you know it makes sense Dont listen if he tells you its not driveable in traffic! THEY ARE LIES I TELL YOU its fine in traffic, I was trying to persuade Max of the benefits too.

[A7NTY]

John/Ed ,

Not really negative, it\'s something that we (re:worx and my chequebook ) are working on.  Geff absolutely bust a gut to get things working as nicely as they are but there\'s a bit of room for improvement!

Replacing my silenced mid-pipe for a silenced but less restrictive one made a peak power difference of 75rwhp which is pretty amasing.  The current backbox is very restrictive (hence being damn quiet) and we\'re also looking at changing the manifold to something a little smaller if we can\'t get power earlier.

Looking at the graph I\'m hitting
200rwhp @ 5000rpm
280rwhp @ 5500rpm
320rwhp @ 5900rpm
340rwhp @ 6800rpm
350rwhp @ 7400rpm

peak was 353rwhp @ 7000rpm

I\'ve upped the rev limit to 8500 on Geff\'s advice to reduce the risk of hitting it when hooning but I\'ve got very usable power from 5.5k to over 8k.  Ideally I\'ll be hitting 80% of peak power by 5krpm (so 280 in this example).

My target is 400rwhp so I\'d like to hit 320 by 5k rpm once the intercooler\'s sorted...  Should be ~1.0 bar boost too

One thing Iain, remember that the dyno will never truly show the lowest boost will come in unless the ramp rate is set really high (load rate) on the road stick it in 5th at about 1000-1500rpm and see what happens then? I expect you will find it comes in a lot lower than the dyno.

Cheers, Ant.

[iaint]

One thing Iain, remember that the dyno will never truly show the lowest boost will come in unless the ramp rate is set really high (load rate) on the road stick it in 5th at about 1000-1500rpm and see what happens then? I expect you will find it comes in a lot lower than the dyno.

Cheers, Ant.

By the time it comes in I\'d be doing 140!

[A7NTY]

By the time it comes in I\'d be doing 140!

OK 4th gear then

[iaint]

Singles are better for top end power, TO4R  keeped hauling arse hard at high end revs ,compared with twins,depends also what driving you want to do,
In town racing stick with twins/Small single, drifting medium to smallish single,drag - biggest single with seroius porting,

Does that sound right..

That\'s a fair summary.  Some singles will give the driveability of the twins with a little more power and a smoother delivery (i.e. no transition).

Really does depend on how you want to use the car.

One thing I\'ve noticed from having a setup where boost arrives much later is I get great mpg as I\'m not gettin ginto boost as much on most journies - only when it\'s needed.

[D1 WTF]

That\'s a fair summary.  Some singles will give the driveability of the twins with a little more power and a smoother delivery (i.e. no transition).

Really does depend on how you want to use the car.

One thing I\'ve noticed from having a setup where boost arrives much later is I get great mpg as I\'m not gettin ginto boost as much on most journies - only when it\'s needed.

i am liking that, being able to stay of the boost and getting some miles for your money is good.  
i use it as my everyday car.  i do fairly drive it though, like i was told when i first joined the forum "you must red line it at least once in a journey:D , and anyway rotarys need to be reved high:driving "
 is the t70 going to be alright?  
and do you really notice the lag, or can you still get it off the lights fast, without being \'completely\' sideways?

[A7NTY]

Well if you want my opinion here it is. Standard twins are sh1te, they make too much heat and the plumbing is a joke and a very very bad one at that. They also suffer from pitiful wastegates and quite frankly I found even an old mitsubishi truck special greddy T78 wasnt at all laggy even on a standard engine. With a 3540 Gt35r or whatever I would think you would have at most a tiny weeny bit more lag, better top end and less heat. An altogether better option.

[iaint]

is the t70 going to be alright?  
and do you really notice the lag, or can you still get it off the lights fast, without being \'completely\' sideways?

It should be fine, it\'s not far from being ideal as it is.

As for launching... I have too much mechanical sympathy and last time I tried I nearly stalled.  Need to practice a bit

[John Yorke]

is the t70 going to be alright?  
and do you really notice the lag, or can you still get it off the lights fast, without being \'completely\' sideways?[/QUOTE]

All depends on your driving style, If you lauch sympatheticaly at 3 -4k there aint much that will stay sitting beside you. By the time you are hitting full boost you will be on your own.
If your intention is to keep it as a daily driver you might want to consider a less brutal turbo though, it will be less strain on your engine, in other words you would have a longer time between re-builds, and better fuel consumption.

[D1 WTF]

john yorke- i am pretty sure i am going with the T70 but i am only getting the 1 something hotside.  so not to big, so should still be ok, i hope.  
is it not possible to have a couple of maps on the apexi?  one for motorway, mainly off boost and one for fun days(eg. raining days,lol)  ?

[John Yorke]

john yorke- i am pretty sure i am going with the T70 but i am only getting the 1 something hotside.  so not to big, so should still be ok, i hope.  
is it not possible to have a couple of maps on the apexi?  one for motorway, mainly off boost and one for fun days(eg. raining days,lol)  ?

1.15 is a good size for the exhaust. You should fit a boost controller which will give you those options - set up for daily drive .8bar [setting 1] through to 1.2bar [setting 4]for ragging / dragging.
Just make sure all the other bits are in place - uprated fueling, cooling, exhaust ect. ect.

[A7NTY]

Iain, a comparison for you from when our car had a stock engine and Trust T78-33D ancient technology mitsubishi diesel truck turbo. This is either 0.8 or 0.9 bar boost.

120rwhp @ 2400rpm
150rwhp @ 3300rpm
200rwhp @ 4100rpm
265rwhp @ 5000rpm
310rwhp @ 5500rpm
335rwhp @ 5900rpm
350rwhp @ 6350rpm
351.5rwhp @ 6900rpm

PS this is with a MASSIVE front mount intercooler and 4" HKS drag system (I think - might have been feed mid pipe and fujitsubo rear box which is far more restrictive)