The season of hill climbing is all but over and thoughts are now firmly focused on what to do next.
Today I have about 370+ x 320+ engine as:

Apexi FC with AndyF map
Grouppe S headers/helix u/pipe
550 cc + Walbro
TD05 20G
3'' decat system (soon to have a sports cat)
Optimax and NF
Parallel fuel mod/oil breather
Stock panel filter
Sti V8 TMIC and samco hoses.

Dilema:

I have 2 choices I think to build a quicker car, and I would appreciate the thoughts from you all.(I asked this last year and look what happened...)

1
2.5 short engine (stock internals) with the above bolted on using my Sti V3 as a donar.
6 Speed Jap spec/ratio's stock trans + Lateral paddle clutch
Avon hill climb slicks (same as 205 x 16 x 45)

2
Current engine
5 speed Zen box, synchro helical + lateral paddle clutch
Avon slicks

I think both these options will cost about the same.
The work will be DIY for (1) and for (2) somepne paid to do the box internals.

I need a faster car, not a Rolling Road Queen car, so strong low rev boost and an emphasis on TORQUE.
On a typical hill climb I am about 1.5 seconds on a 50 second hillclimb behind the EVO.

All thoughts welcome.

 

My thoughts on it would be gearing to suit the event.

I've never been to a hillclimb event before, so don't know what to expect, but i would think if you have several events which are similar in terms of bends and speeds attained, then you would gear the car to suit the majority.

I assume hillclimbs are all short straights, plenty bends?

 

And if there are a lot of bends, get anti-lag, so you don't waste time waiting on boost

 

i think that the JDM gearing with a td05/06 on a 2.5 will just be too short.

Id look to find away to fund the car using a 5spd and a 2.5 with antilag, launch control etc

David

 

A datalog of a typical run might help decide, even just ECU data with TPS, RPM, boost, vehicle speed which FC datalogit and a well secured laptop could easily do. Even better would be to add some G-traces through say an AP22 or similar, but that might get complex.

My thinking is that you would then see where the "deficiencies" lie?

Despite being a power junkie, I would have to think that better tyres (adequately warmed - presumably important on a short event) would make far more difference, but presumably you're not on really sticky stuff yet because of sympathy to the gearbox? Also, what about some start line cooling - CO2 or nitrous spray allowed? More water spray? Pre-prep with ice before hand? It is astonishing how much heat could build up in the engine bay and presumably be lost from the tyres and brakes?

 

Great start!
The hills are very similar. Take your favorite country lane, about 1/2 mile long. Take the fastest run at it as you know noboby/thing is coming the other way.

I am on Kumho V700 soft compound which grain-up like slicks on a run. they are noticeably hot after a 50 second climb.
Avon slicks are much softer again. Havn't done the slicks yet due to the stock Sti box.
Thought about the Sti Jap 6 speeder to try to get some sort of LSD in the car with matching rear diff.
I just wish MarkA had done his car and hill climbed it so i could see the effect.

The car gets a TMIC cooler tank full of ice cubes about 5 mins before the off, the TMIC is drowned in cold water at the same time, and the spray is switched on mannually for the entire hill climb duration.
Co2 is a real oportunity for the TMIC (which I want to keep)

None of this will give me the torque, but the run in the EVO made me think about RA type gearing again. I tried an RA box on 4.11 diffs last year and it was slower up the hill compared to the Sti V3 box.
Maybe Type R ratio's are better? I need a normal 5th to cruise with to and from the events.

Seems a 2.5 with a UK 6 speeder is right? (cost= 3K plus 1.5K)
Zen box = about 4K when finally done.

Keep it coming!

Graham.

 

there is an uprated 5 speed gearbox for sale on ebay now which should be able to cope with the power of a 2.5ltr engine

 

It is SOLD.
Absolute bargain if it is in top condition, and perfect for my car with the current or 2.5 motor.
Graham.

 

1 day left starting bid at £750 and no takers and its quaife stuff with semi helical gears

 

I know!
Maybe another nugget of gold like that will appear with my name on it next time. A steal if all is well with it.
Graham.

 

Patients my son all things come to those that wait!!

DW - 6sp JDM to short, surely that's the point of hill climbing, quick acceleration and not high speed runs?

I'd have a word with Axis about either a stg3 (2.5) or stg4(2.33)

 

Is nitrous allowed in this sort of event? If so even a small shot might be enough to give you the edge you've been looking for. There's some clever kit out there now that can feed it in/back it off progressively. Much cheaper than the other options too.

If thats out of the question do you have an AVC-R, when I went 20g Andy said that it would help it spool quicker and get you the bottom end punch you're after.

 

Graham/Mark, a big lesson I've learned, converse to all popular thinking a short ratio STi box is the exact oposite of what is needed for hills/sprints, my gearing with PPG Dog box and 4.11 diffs have proven to be fantastic at every venue this year. Much better than the STi 5 ratios with 4.44. Saves a gear change and with the 2.5 there is so much torque there is no need to be lower geared (or in a lower gear).. proof of pudding .... track records at every sprint. Under the record a Doune, Forrestburn, not Fintray yet, but it was wet. Next year hopefully a clean sweep.

---john---

 

I think you have your options muddled up Graham

I would be thinking this

1
2.5 short engine (stock internals) with the above bolted on using my Sti V3 as a donar.
5 speed Zen box, synchro helical + twin plate clutch
Avon hill climb slicks (same as 205 x 16 x 45)

2
Current engine
6 Speed Jap spec/ratio's stock trans + twin plate clutch
Avon slicks

Revvy ness of your current engine will make better use of 6 speed box, and on a hill climb, i would have thought a JDM or UK would make no difference, as 1 to 4 ARE identical, 8000 rpm in 4th is good for 110mph on 3.9 diffs.

With a 2.5, you can go with taller gear, as the additional torque will offset any loss the taller gearing may provide.

Note the change of clutch spec too.

 

That is interesting.

Firstly, Nox is a no no.
I had the same issue with the RA box as John says, all that shifting takes too much out of driving the car in the bendy bits.
A 2.5 gives all the torque reasonable (and that the chassis can cope with).

Please explain the twin plate clutch to me. The EVO uses one as nothing else would stay in one piece (shows the engine output?).
I also take your point about the gearbox swop. For some reason I thought the Jap ratios were shorter in the Sti than the UK Sti.

Thanks for all the input and interest...any more?

Graham.

 

Ooh, good thread. Well done

Is a TD05/06 20g different to a TD05 20g or are we talking about the same thing?

What's your induction path like at the moment? Will you be getting 740's for the bigger goal? Will your TMIC hold together at the boost required? Your torque is low ATM for the spec you have.

I drove a 2.5 properly for the first time last w/e and it was torquey This particular car needs some work on the top end rev wise but low down it's a lot of fun. The spool impressed me too for a stock TD05 and Gruppe S headers.

Based on that drive I'd say 2.5 for the punch you require over short distances.

F

 

As P20SPD says, JDM 6 speed only has 5th and 6th gear shorter than UK spec box, 1st to 4th are identical.

 

A paddle will do for your application, factor on using two friction plates per season, changing mid season to avoid dissapointment. Stick a 2.5 in and leave the rest the same. Confused by your 'sold' comments about ebay, so I'm assuming you don't mean this one.

http://cgi.ebay.co.uk/ws/eBayISAPI.d...MEWA%3AIT&rd=1

 

So wouldn't the 2.3 be better for the hills then?

as in best of both worlds IE more torque and still be high revving?

 

A 2.3 would better, yes, do you have one lying around 20G will be running out of puff at 6500 on a 2.5 anyway so why bother with a screamer on that turbo.

---john---

 

Graham

With regard to the twin plate plate, more of the big power boys are convinced its a fit and forget application for 400 to 550 of bhp and torque, anymore and its close to call. The LP paddle will cope to some extent, but with general driving IMO it wont.

The twin plate offers superb driveability for day to day running (ie driving to events, holding clutch in queing traffic etc) something a single plate wont. If you trailer to event, then single plate it, as you dont at present, twin plate it IMO.

Add the fact you will change to full on slicks, and the load through the drivetrain will be far more substantial, and as you dont like clutch changes, why fit one that needs changing 50% through the season.

Due to my yobishness, i have just totally destroyed a twin plate clutch with a car producing in excess of 550 of each. I was deaf as a post due to flu, and didnt hear the clutch slipping until it was too late (but was told it did it in every gear). However, i still did a 10.6 1/4mile. If i had done that with a single plate, i think i would have stood still in 1st!!!!!

Floyd, your talking about the same turbos .

The next couple of weeks may be interesting. I have just finished rebuilding my uprated EJ257 shortblock into a new age car, complete with JDM 6 speed, and ditching the TD05/06 (compressor/exhaust) and fitting a full on TD06. Target was 400+ of each, and having rung round all the well know names, including RCMS, the general concensus was a twin plate clutch.

As sad above, a 2.3 would be better, as it will accomodate the torque and revs, but the budget is in a different scale.

John, fit a full on TD06 and it wont be running out of puff at 6500

All the best

Steven
(eargerly awaiting the return of his car from Scoobyclinc after a respray, and can then install the 2.33)

 

Graham, what if Evo turns into MY06 Spec C with uprated 2.5 ?

Iain

 

Then I will return to my trusty 911, as I simply will never cope with that!
Sell the Sti (less the fab AST suspension) and restore my old Lambretta!

There is every chance it could happen as Roy has had the EVO for 5 years and is getting bored!

What have I done to deserve this?

Where do twin plate clutches come from, and for what budget?

Things seem to be gravitating to:

2.5 + Stiv3 donar, + 6 speeder + twin plate + slicks.

Will this catch a Litchfield Type C with 2.5? After the drive I had in the stock Black one I doubt it. Roy will never stop at the bolt-on level, there will be more!

Graham

 

Steven you're right about the 20G, hence the front entry Fannymold, Tial wastegate and assorted pipes lying in the garage waiting to be mated to a GT30R. Graham, your car with a 2.5 will kick seven shades of sh1te out of Ians type c 2.5 (no offence Ian, we are talking a stripped out competition car here). Twin plate clutches are in excess of a grand.
Driving to an event on a difficult clutch and needing a clutch with 'road manners' are two different things. Get a good paddle it will see out a year, just keep a friction plate in your spares box

 

John I don't think you have seen Iain's STI 10 Spec C racer yet that's been prepared by Power Station not a lot beat it at Donny Tuner day.

The Quaife box on eBay is running the same ratio's as I had in my 328 bhp WRX, 112 mph in 5th at 7000 rpm way too short IMHO but it was fun to drive more like a bike than a car through the gears.

I still think the STI 6 speed would be too low aswell, ok in newage due to the larger rolling radius tyres. Redline in 4th on a standard 2.5 bottom end would be in the region of 100mph. You need to work out max mph on fastest hill climb and then see what ratio you need to stay in best torque band.

 

Graham,
I think Steven's advice is sound.
Though not sure you would need the twin plate. IIRC you use the car only for competition + to and from events (maybe the odd weekend play)
I'm running an LP 5 paddle on the 2.5 and it is very well manered. It can be awkward in long slow moving traffic queues, but still very useable

If you go 2.5 I would get a Zen built box. The 6 speed is heavier and you don't need the extra gears because of the torque.
If you decide to stick with the STI3 then the extra gears may well be needed. Get a UK 6 speed if you can, it will make traveling to events easier

2.33 seems to be the way to go for competition engines, but they are prohibitivly expensive and you would then need the Zen box on top


Steven,
I will be interested in how the TD06 performs. What differances/advantages are you expecting compaired to the TD05/06?

 

I think you need to do some logging of revs/speed on the hills and try to work out the best ratios. (should have thought about it before the end of the season)

 

The Sti V3 ratios are surprisingly good for the hills I do. Be nice to have a slightly longer 1st, but the rest are ok.

I have seen and looked closely at the Powerstation/Litchfield white racer, and it is simply stunning.
Looks sooooo much better than the stock road car, but the presentation is ace.

Worth driving there just to ooggle.

As to the Jap box:

With so many ratios it must be possible to find a match to the 5 speed?
The cost of the obviously good Zen box is the same as 2.5/6 speeder.
You can get an AP organic @ the 6 speeder's larger size too with the 6 speed flywheel ( )

Graham.

 

Maybe Zen will do a discount for sponsorship

 

PM me if you want contact details and a guide price for a 2.5, 2.33 or 2.6!!

I thought the 6sp JDM had strong selector forks, might be useful for you as you crunch down the box

Mark A