Dale FZ1

So is yours 100% road use, or some track work included? At this stage it's rated as bling only?

Dave, I have had to make cooling the priority because I was thoroughly peeved with not getting a full run in each time before the ECU failsafes started kicking in, and also the potential reliability woes with it running hot. I agree it makes most sense to combine the undertray/splitter as one unit for aero and cooling. Either the cooling engineers know something more than us, or the production accountants worked out they could pull costings down without affecting stock performance. It would seem to me that the stock plastic tray from the lower radiator support - front crossmember would give a decent return on investment for cooling, and they didn't worry as much on the aero side given the GTR is the hero model. Would be good to have a close look at a dead stock GTR and see what tricks the factory used.

So do you have something installed under the engine, or a splitter on the front bar?

That's the top lid or plate that I was looking to make. But purely if it was functional, as per the thread title. It appears that running the top plate from top of intercooler and sealed against the radiator roughly at two-thirds height is something that would work. GTR running an OEM intercooler with (presumably) less restriction to the airstream might make things different.

Nice work Dave. I agree that multiple heat exchangers makes getting decent airflow that much harder. Interesting to note that even without side plates you got a good result. Does the S13 run a front bar splitter or the splash guard underneath the engine?

After this info I had to check for myself Ty. Is this what you were referring to? http://www.autospeed.com/cms/A_2160/article.html Makes for interesting reading, I just don't have heaps of time ATM to go road testing with a manometer. I followed a fair bit of info written by Edgar when he kicked off Zoom Magazine, even back then he was big on testing and validation. Clever stuff that proves why something works.

That info could be gold, Chris. Ignore the chassis being used, the issue is managing airflow through two different height heat exchangers and making them both work well. That would have effectively given two different pressure zones at the radiator core, and make the intercooler core continue do its thing at speed as well - theoretically at least I wonder how well it worked?? It might be a challenge to the cooling efficiency of the radiator if only a portion of the core gets exposed to full airflow but sounds ok. It may be that I only need a horizontal divider from top of intercooler height, and sealing against the radiator. The bonnet should work well enough as a top guide plate, with good sealing rubber mounted on the support panel. Hopefully someone can post up some pics of their work. Good ideas are one thing but the devil is in the detail.

For interest's sake it would be great if you can find the direct link. Initially I hadn't considered the effect of that plastic "splash guard", until I experienced overheating issues. Then I was directed towards thinking about air pressure differentials across heat exchangers, and it occurred to me that the simple plastic guard was actually helping to create a draft through the engine bay and pull air through the radiator. Simple concept, but takes some thinking through. For the next event that guard will be back in place, unless I have enough time to fit a diffuser direct to the bottom of my front bar.

This pic shows the side plates and the rubber seals if you look closely. Little bit tricky to show the lower guide but it's there. I'm in the process of fitting a GTR replica front bar with bigger openings, and there will be further guides fitted to channel air onto the intercooler rather than allow it to spill around the sides.

Interesting that yours ran hotter with full ducting at sides and top. I had in mind to leave a slot to at least let a little bit through the grille passage. It might be a balancing act with intercooler spec to achieve decent airflow through it, and then also through the radiator core. I want them both to work at least reasonably efficiently. My understanding is that air will pass through successive cores only when there is a pressure differential on either side ie. high pressure to lower pressure. My logic says that with no top plate the bulk of radiator airflow will surely pass through the grille and render the intercooler fairly much a loaded heat sink with nowhere to shed heat because the air isn't passing through it. I believe that my radiator had been doing that because of poorly thought-out air control and passing a cold inlet air duct unsealed into the engine bay. Ultimately the best bet will be to try running with and without top plate, log the data and see. There are enough SAU track runners, no way am I getting the Neil Armstrong feeling with this one. Post up some pics and ideas and share the experiences.

Long story is I experienced some cooling issues with the R33 at track days. Had a good hard look at things, and it appears airflow through the radiator core was inhibited. I've got onto most of the fixes I can identify, with a little help/comments from a few people on SAU. I am very conscious of proper sealing of air gaps, and quality/spec of the radiator. My R33 now has guides installed at bottom and sides of the intercooler:radiator gap, trying to establish if there is any gain in putting a guide across the top as well? My thinking is that if I don't run one that full airflow through the grille will give the radiator a high pressure zone but effectively render the intercooler a high speed barge board. Unless I force the air to travel through the intercooler first by using a top guide. I'm looking for comments from those people who have installed and tried out air guides between FMIC and radiator particularly for track use. I don't believe road-only experiences will be of great help simply because the road speed/engine speed/loads are sustained high enough for long enough to show up strengths or weaknesses in cooling systems. I know this is probably more motorsport/build/fabrication related but figure posting up here is appropriate. Comment/discuss please.

Looks like you're pretty handy in the fabrication stakes there Mick. Well done, now get into running this thing up with some boost into it.

Not sure with RB engines, bu I understand some shim-over setups have bad from for spitting shims out when used at high rpm for extended periods and maybe if cam profile is altered from stock. Some Neo engines run alloy buckets though - light weight = good.

And was it just idle thought, or has the plan been progressed to something concrete?

I'm interested to know what ride height was used with this setup, and also whether this one or Simon's had any clearance issues with the front upright near full lock? This build is taking its time but the collection of goodies sure looks to being as good as it gets for a 2wd R33.

All clear Scott, thanks. So you're using the good fasteners Troy? Source/supplier?

Yes I did think it should offer a theoretical advantage, hence the question. The Tial V band inlet/outlet fastening method is very attractive to me from an ease of servicing/installation viewpoint. A mate who runs an Evo gravel rally car (with anti-lag) has experienced a lot of trouble with the 3-bolt flange nuts coming loose in just one stage (so as little as 20km of competitive driving). Extreme heat cycling partly to blame, but it was fixed by sourcing flash Ralliart spec nuts and conical spring (belleville) washers. Cost to regular plebs like us would be 4.50 per washer (need 2 per stud), and 21.50 per nut... Madness but that's what it takes to keep the bastards tight. Slight deviation, but makes me wonder if the 3 bolt spec is more prone to having the flange nuts loosening themselves?

Scott it's hard to keep up, but your post earlier today suggested that the flow increase was related to the round inlet/ 3 bolt style turbine inlet. And that was the direction/purpose of my enquiry. Then things moved along seamlessly with comments about extra flow capacity related to bigger/different billet compressors. So what gives? Consensus or hard information about whether Mitsu-style 3 bolt inlet is a good thing?

Troy is it only the Trust turbine housings that are 3bolt/round inlet configuration, or do Kando supply them in that style also?

They're not always consistent with other detail going onto the ID tag. 700382-5012 = GT3037R aka GT3076R. Don't look too deeply, its not important.

Agreed, but the maths is (for me) where it's at to ensure the different configurations ARE going head to head. I don't want to see a one/two make championship, and I would like to see a Drivers championship. Where's Jack Monkhouse?

AWD cars are very efficient point-to-point cars through the forest. No doubting that. But if all I want to see is something fast I can go to the nearest airport and view the takeoffs. The 2wd regs are an overdue step in the right direction from the viewpoint of spectator interest. And I think that a sensible approach to regulating for equity/ parity between N/A and turbo via weight and/or inlet restrictors would work. Might also be a workaround for cost savings so people don't feel obliged to have to build a new car each year or 2 just to stay competitive? The economic climate doesn't look like getting any healthier anytime soon so any competitor interest is better than dwindling numbers. I think the Poms have got it right with their touring car formula. They are prepared to play with it to ensure it continues to work rather than let things go and then wonder what went wrong.

Having trouble getting the regs to download so can only go off comments posted above. The 1.7 multiplication factor would always see a turbo 1.6 running in a different equivalent engine capacity class. Torque hauls cars out of turns, but getting a FWD with massive midrange to pull, steer, and not eat its front tyres in a single stage might be a challenge. I'd be all for ballasting the turbo cars if that meant hearing a b.it of N/A bark in the forest. But I don't think weighting up FWD cars is the way to encourage broader participation. How many small/medium RWD platforms are out there these days? Not many .

That is a pretty accurate description of what to expect. Cubic capacity gives a lot more torque at idle, turbo lights up early, and can blow hard to make a lot of stick. For road use the 0.82 housing is very good match, maybe a bit restrictive if you want to run for extended periods at high rpm ie. on the track. The GT3037 might be a superceded unit but it is a good thing.

The compressor can only flow to its maximum capacity. Sure, bump up the boost and watch the midrange soar (good times ). Even running E85 you will run into a restriction with what the turbine can flow up top. I'm guessing a bottleneck around 320kW, but a ridiculously fat midrange with 25psi.