BADASS SR510NA

[kwalmsley]

So Taupo SS2000 RD3 sucked ass. Car was handelling like a pig, massive understeer into massive oversteer, lapping 2-3sec's slower than normal and getting blown by cars I normally run rings around.
The only good thing would have been meeting Morgan - good to meet you dude - thanks for coming down.
Been busy fixing a few things which will hopefully sort most of the probs we encountered but will post an update on these once completed. Also whilst addressing these areas we've decided to install a long desired addition - sneak preview below, so in the words of the Pointer Sisters....... "I'm so excited, and I just can't hide it, and I know, I know, I know, I know I know I want you, want you, I want you.



That's what $2.5K will get you and I'm hoping will give me (once dialled in) another second or so around most tracks and be pretty much on the right path (finally) in regards to rear suspension.

[PL510]

Very sexy!!

[nzdatman]

very nice. hope they work as good as they look.
good to meet you too, see you next time you're down.

[kwalmsley]

Here's what happened to the original axle on the start line at Puke. Sheared the end off really clean and square - almost looks like it was machined off. Had them hardness tested and all looked ok for the type of steel it was so really don't know what went wrong here?



Anyway we decided to start again and have another go. This time we have chosen to use 300M steel which is largely regarded as the best axle steel you can get. Had to bring it in from the States. Did some research and there's a dude in the States that makes alot of race CV sets for all types of vehicles - he makes Subaru axles in the standard size from 300M steel and guarantees them (for 1 year) to be good for 600hp, so hopefully should be ok turning my 260 odd Will keep you posted on that.





Blank done


Cutting the splines

[kwalmsley]

Also been busy trying to sort the handelling problems experience at last Taupo round. Ever since moving the lower control arm locations up in the front crossmember (see previous post on this) we haven't been able to get as much negative camber or caster as we would like to run (due to limited guard clearance). This lack of alignment had chewed out the front tyres prematurely which was contributing to the massive understeer experienced. One of the front inserts had gained a leak also which didn't help things much either. Had these dyno'ed and rebuilt by Racelign. Decided to machine up some new adjustable top plates with the rosejoint boss moved to enable more camber and caster to be added within the standard guards, also saved a little weight as you will see in the photos.

Old plate on the left - new on the right.






Unit of measure displayed on the scales is kg's so new ones are a whole 110grams lighter each side - That's an extra Bigmac I'll be able to eat prior to racing

Fitted back up - a fair way over compared to the old plates so hopefully should give us the extra adjustment we were aiming for.

[kwalmsley]

So been plodding away also with all the spare time I have (NOT) on the rocker cover. Infact spent way too much time on this thing and was starting to get dis-illusioned about the success of this part with the more work I did on it, however decided to carry on and today I'm really glad I did!

Finished the grinding, bogging, sanding, priming etc and then got http://www.autotouch.co.nz round to flow it up for me.



Then wax on wax off Daniel-Sun. Got to do this at least 5 times. I did 6 on this as I've learn't from previous experience not to short-cut with this step.



Also lesson learned from previous experience (failures) that applying the gelcoat can be tricky - can't apply it too thick and not too thin or you get all sorts of failures (aligatoring/cracking etc) if not done right. For this part I decided to get someone who knows what they're doing to apply it for me. Gave it to Dale Fibreglass who make Dale ute canopies and they sprayed on the PVA release and Gelcoat for me - only cost $60 and they also layed a first layer of glass tissue to it which I thought was very reasonable - thanks guys!

Bought it home and got busy laminating - did 4 x layers of CSM (Chop Strand Matt) to form the mould.



Trimmed it up and revealled some voids where the CSM hasn't formed to the tight and complex curves of this part.



Simply mixed up some more resin and used the trusty old McD's cup to poor this in to fill these voids like so.



Then cracked it out off the plug - always nerv-racking at this point as you don't know how it's going to look. In this case was all good, largely credited to the correct application of Gelcoat by spray and someone who's experienced.



Wax on, wax off again Daniel-Sun. Another 6 times (never skint here or you will live to regret it). Also carried out all prep for the part lay-up. In this case as the part is going to be only 3 layers of carbon I decided to include some polyurethane foam core to the large flat areas to stiffen these areas up.

Sliced some 5mm-6mm thick slithers from this poly-block and then sanded a profile to one side to fit the curves of the cover. Such nice easy stuff to work with.





Then get everything ready for the lay-up as once started you don't have much time before the resin starts curing and you want to get it under vacum as soon as possible to ensure a nice defect-free (or as much as possible anyway) finish. For this part I did 2 layers of 196gsm Twill Weave Carbon Fibre then the foam core then another layer of the said cloth to finish. Also had to think about operating temperature of this part as the engine oil can some times get up to 110deg C. Had to shop around for a suitable laminating resin that would handle that kind of heat without softening. Ended up getting some Vynil Ester resin from Adhesive Technologies which they sell to the likes of Brittan (Motorcycle) etc and is good for 140deg C.

Part layed and now in the vacum bag.



Left this under vacum for 3 hours then left overnight. Came in in the morning and took it out of the bag and placed in the our high-tech (stove in the workshop kitchen) oven to post cure. Did this at 80deg C for 4 hours.



Let it cool down and then nervous as started to pry from the mould. It's always nerv-raking at this stage as usually it's taken alot of time to get here and you don't know what your going to find. In this case I was pleasantly suprised



That's straight from the mould - STOKED AS!! So stoked cos along the way talking to all these professionals (buying resin, getting Gel applied, reading the books etc) I was getting less and less confident of the successful lay-up of this part. They all reakon the carbon wouldn't form around all the tight and complex curves of this part, however i decided to continue anyway and apart from a few minor areas requiring a little TLC it came out really good, I'm rapped as with it.

So 29 hours to date to get to this stage (yep she's gonna be a 40 hour rocker cover by the time it's finished - tehe) there was only one thing left to do - weigh it of course.





If you can't make out the reading that's 0.37kg (370grams). I'm going to carve out the aluminum flange from the alloy rocker cover and bond this to the carbon one so it seals well to the engine so I reakon by the time it's finished should only weigh - 1kg - 1.3kg, a whole 2kg's lighter than the alloy one - I get pretty excited about weight savings nowadays no matter how small they are.

Also had to drop it in the engine bay for a sneak preview of how she's going to blend.

[kwalmsley]

Oh - also got the ITB castings back today. Did ask for these to be done in Magnesium, however they've just done them in C601 alloy .



Don't mean to sound ungrateful as he's a mate and did them for a box of beer, however sometimes it's easier to just pay someone you don't know so at least you can complain if you don't get what you want or ordered. Anyway these will do the trick for sure - so Thanks heaps Leon! Will do a bit of finishing, them send them to get abrasive rolled to smooth them similar to my existing ones. Once that's done it's off to Lynn Rodgers with the head for flowing.

[dattohoe]

This thing is a true masterpiece i cant believe it only weighs 810 kg! these things were light enough at factory curb weight of something like 920, and with an sr in it, i though it would be around 1000 kgs now! shittttt i hate to thing what mine weighs now with fj20 and r200 and big c.v axels in the rear.... im scared to weigh her....
Nice work tho!

[skidmrx]

this car tickles all the right spots.Love seeing it progressing(not that it needs it).

[kwalmsley]

Thanks guys - comments are always appreciated. Quite enjoying the posting of progress also, provides a place to keep a journal on it as such and starting to get on a roll now. Few bits 50% done so will update upon completion shortly.

[240znz]

Looks great. Where did you get the CF from?

[kwalmsley]

Looks great. Where did you get the CF from?

http://www.nuplexcomposites.co.nz/ - however I think most composite suppliers would have it.

[2 doors]

well done mate, I love the fact that you didnt let the EXPERTS put you off, quite often there failures are due to not being able to charge out the time required to make a product, thereby forceing them to cut corners, to bring the time down to enable profit to be had.
and many thanks for naming the places where the products can be purchased, will save others much time id guess.

[max_1600]

Hi Kane

Seriously impressed with your racer. Sits right beside the BRE cars for quality in my books.
I have been meaning to open a dialogue with you for a while seeing as you seem to
always push the boundaries with the 1600's. There are a few things I would like to have got around to
when I was racing a 1600 but never could manage. Might be of interest to you.

Rear Suspension:
Have you got any thoughts on mods to the rear suspension to reduce the camber and toe change ?
I came across a thread on The510Realm.com where a guy had designed a new
rear A-arm that uses the standard pickup points on the rear cross member.
Seems like he drew on the RX7 (later series) independent rear end concept.

Link to the thread is http://the510realm.com/viewtopic.php?f=29&t=12635

I also did some research into the BMW E series cars with their almost identical rear end.
Their race cars have a different rear cross member.
For racing they reduces the angle of the cross member relative to the chassis from 15 to 12 Deg.
Has the effect of reducing cabmer/toe change.
They also lift up the A-arm pickup points to increase anti-dive.
The way they make the Camber/Toe/Roll Centre adjustment is excellent too.

http://www.e30m3project.com/e30m3performance/tech_articles/susp-tech/index.htm
Check out the section on IRS roll centres - applies directly to the Datto.

I used to race a 1600 in U2L class and have watched a fair few others.
Common to all of them is their tendency to oversteer late in the corner and
thereby make it hard to get back on the power, costing lots of time.
Controlling the toe change will be a big help in this area.

With your new engine I thought you may be intestested in the following thread from Performance Forums

http://performanceforums.com/forums/showthread.php?t=67248606&highlight=sr20

One of the best NA head mod threads around. In the thread the guy (TK) uses an engine simulator
to model the right inlet and exhaust tract dimensions for an SR20VE head on 2L NA motor with
max power at 8000 rpm. He performed one simulation with 50mm ITB's but found it pulled 20HP off the top end!
Given that you are in process of building ITB's thought you might be interested.
Seems like a Plenum with 90mm TB is the go.

Would be interested in your thoughts Kane.

Regards

Max

[kwalmsley]

Hi Max,

Thanks for the links mate, haven't got around to looking at the BMW one yet but the other two offered some good info. Those rear trailing arms are the business, always planned on doing a moly tube a-arm for mine eventually but those definatley put a new spin on things and I quite like those (or a variation of them) as a way to go when we get round to it, they're very nice and offer lots of adjustment too .
We're sort of flying blind in regards to suspension at the mo. We had commisioned a guy over here who does alot of work on the NZV8 tourers and was working with a few of the Aussie V8 development series cars to help us with direction for suspension. He has a good software package that models up the existing suspension and then can play with it to optimise as such prior to going ahead and fabricating, however he took all the measurements and got a model working and then has sort of dissappeared so left us pretty much stranded . So we've just started doing bits at a time to hopefully progress in the correct direction. Current suspension is still very basic given the original intended purpose however we seem to be fairly competitive already in our series against far more developed cars.
The motor thread was interesting too - his software looks pretty cool and gives good insight into flow requirements for hp etc. Looks promising for us, we are using (and use on the current engine) a GTi-R head, different port shapes again from the std SR20 and SR20ve. From memory I think our original head was flowing somewhere near 318cfm inlet, however will confirm this and other flow figures with Lynn Rodgers when we drop the new head off so we can compare with TK's figures. Also from memory (bout 5 years ago now) Lynn thought he could gain more, however was all that was needed to meet the original breif.
As far as the ITB's go I think mainly the hp decreases due to the sharp throttle to head angle required using off-the-shelf ITB's and the manifolds available. Looks like most of what TK is talking about there is standard aftermarket stuff. Most of these would use a manifold appriximatley 50-80mm long which makes for a very sharp taper from 50mm throttle body to the inlet port. Ours taper down over around 200mm making this angle far more forgiving and offering much more flow. Also I think the port on the GTi-R head maybe a little bigger than the VE port (not 100% on this tho) which would help this taper even more. I still believe this is the right way to go for us (ours are going to be bigger than the mentioned 50mm also by the way).
All being said tho - thanks again for the links - hadn't seen these before and definately some well thought out info which will offer some new direction in areas so much appreciated - already ordered a copy of the EAP software that TK is using for annalysis of the new engine