E30 with SR20DET

[Theo]

Another bit of flame throwing with a little slide coming out of druids which along with the long final corner was still damp and very low on grip. The car kept doing a sort of floaty four wheel slide through the last corner in particular.

[GeoffBob]

I was using the balance bar adjuster to tweak the bias, the proportioning valve is left alone. You advised I set the rear line pressure to 500psi - I think at some point I'd like to test the rear line pressure with a gauge to check I've got the valve set correctly (I never did find a graph for it). Perhaps I could even swap it for a screw type for finer adjustment and then lock it in place somehow.

Excellent idea Pressure is conserved through the pipework, regardless of T-pieces etc. Hence, with one back wheel raised, you'd need to insert a pressure gauge in place of a bleed-nipple and then get someone to push the pedal. Keep in mind though that the proportioning valve doesn't cap the rear pressure, it simply "proportions" how the rear pressure varies as a function of the line pressure to the valve. Hence, you also need to tee a gauge into the feed line to the prop valve. The "knee pressure" (adjusted at the valve handle/knob) is that pressure (measured at the input to the valve) at which caliper pressure rises slower than the input line pressure. Before the line pressure reaches the knee pressure there should be a 1:1 relationship between the line pressure and caliper pressure.

On a seperate note, I wa getting intake temperatures (post intercooler) of around 25 degrees C, when the ambient temperature was something like 6/7 degrees. Is this good/bad/average?

This all depends upon how much boost you were making and how long you were sustaining boost for. The higher the boost pressure (relative to atmospheric, by definition) the higher the temperature of the air coming out of the turbo (due to adiabatic heating, and the inefficiency of the compressor). Hence, the longer you make boost for and the higher the boost pressure, the more heat you will have to dissipate into the body of the intercooler (and hence pass back to the air passing over the intercooler) in order to restore the intake air temperature back to ambient. Personally I would say that roughly 20’ higher than ambient at the intake manifold is pretty good, but this is assuming that you were pushing her fairly hard. If this were the case cruising down the motorway, not making any boost at all, then I’d say you had a problem.

[Theo]

Right, bit more faffing that I had anticipated to to brake pressure testing. I was thinking I could just test the pressure at the caliper with the lever in it's 6 different positions. Perhaps I'll just have another attempt at finding the relevant graph!

With regard to intake temp, that was 'hard' driving at 1 bar boost for 15 minutes or so. When cruising off-boost the air intake temp is the same as ambient or there abouts.

Another positive I've just thought of was the total lack of fuel starvation now that I have a swirl pot fitted, even with only 1/4 of a tank of fuel. When I did Brands in 2008 the car needed 1/2 a tank or more to stop prevent fuel surge.

[GeoffBob]

Right, bit more faffing that I had anticipated to to brake pressure testing. I was thinking I could just test the pressure at the caliper with the lever in it's 6 different positions. Perhaps I'll just have another attempt at finding the relevant graph!

Good idea. That graph will tell you exactly what you would have found out doing the "two-gauge" test. As I recall I did your brake calculations using the graph from a Willwood prop valve (or was it a Tilton?). I'd suggest contacting whoever made your valve, get a graph from them, and simply set it to the specified position as per the graph.

Watching your 2nd video I'd say that your car is well composed on track, you've obviously done a good job of setting up your suspension. No obvious signs of pitching and/or rolling (as best I could see).

With regard to intake temp, that was 'hard' driving at 1 bar boost for 15 minutes or so. When cruising off-boost the air intake temp is the same as ambient or there abouts.

Then I would say that your intercooler is more than adequate for your application ”“ well done. FYI I determined an intake manifold temperature (at thermal equilibrium) of 55’C running 200hp at 1 bar boost continuous at an ambient temperature of 35’C (typical for down here) for my own engine. So that’s a 20’C increase over ambient. While I realise that our turbochargers and intercoolers are quite different, the point I want to make is that a 20’C rise over ambient (after the intercooler) sounds fairly typical to me. Anyone who records less than this is probably running a larger capacity 6-pot engine making the same hp on less boost.

[Theo]

The graph you used was for an AP valve (which has 7 possible settings), but mine is made by Wilwood (which has 6 settings) - who didn't reply to me when I contacted them requesting a graph. I'll try again

I' very satisfied with the composure of the car, It really is a world away from when the car had the 3.5 engine and different suspension. Last time I was at Brands I destroyed the NSF tyre in no time, now that the bodyroll has been virtually eliminated the tyre wear was not so concentrated on the corner.

I'm glad the intercooler appears to be effective, I had slight concerns over it's efficiency as it was an ebay cheapo. In the unlikely event that we have a warm summer next year, it'll be interesting to see whether it manages to maintain a charge temperature of ambient+20.

Sorry to keep gushing on about the car, after so much time and quite a bit of money it's great to have finally used the car for it's intended purpose and even better that it seems to be a resounding sucess.

[baptie0]

well done theo

[winx]

nice one fella, very pleased for you!

[DRIFTBOY]

Congrats mate, I'm pleased it worked well for you!


Great thread this too!

[n1tr0_9]

Thinking back to when we did the set up.....

...the scales were placed under the car, the weights were measured and initially the front left was much lower than the front right. So the platforms of the front left and rear right were wound up. This improved the weight distribution across the front. That would suggest that the computer was plugged into the scales the right way round. I still dont understand why when Theo gets in, the weight increases on the lefthand side more?

[aluntirlan]

Hi,

I'm about to do this conversion myself. I have a complete 200 SX donor car that has 250 -300 bhp and I'm very excited about the swap. I'm after a pattern/measurements for some engine mounts - can you help?

Thanks - Alun

[Theo]

Hi Alun, sorry for taking a month to reply. Karan might still have the pattern for the engine mounts, I'll ask him about them next time I speak to him.

Now for an update on the car.

A proper electronic boost controller is now fitted and working perfectly, keeping boost at a safe level and adjustable in-car. It's a Biltz DSBC Spec R incase anyone is interested.

Fitted a GReddy baffled sump to the car to guard against oil starvation which can be a killer on the SR20, apparently.

Also fitted a shorter ratio final drive, replacing the 3.64 I previously had with a 3.91 with modified ramp angles to give 40% lock - Thanks alot Gareth! I'm yet to try it out in anger, but had a quick drive and early signs were good.

I've also just booked an open pit lane trackday at the Nurburgring which comprises the Nordschleife and the GP sprint circuit - to say I'm excited is an understatement! This is happening on the 19th April so not long to wait

Little pic from Rockingham:

[appletree]

Make sure you get some pics and if possible some video. the ring in pot e30 turbo is going to be lots of fun, power and great weight distrubution

[Theo]

Hopefully there will be a couple of photographers there getting good photos.

It's going to be a real experience taking the main straight flat out, rather than stopping half way and going through the barriers again for another lap.

I'm preying it doesn't rain.

[gareth]

that sounds like an awesome day you have planned. i'm SO jealous!

slight off topic... why do all the jap tuning parts have such gay names?

does the diff lock up ok then?

[Theo]

They have gay names to deter people from having those sad shoppping lists on the side of their car.

Diff seems to lock much better but I really didn't give it any beans as the car still had normal unleaded in from when I cruised back from the last trackday. I'll give it death once I fill up with super unleaded and report my findings.

[gareth]

you need to have the list down the side of your car
HALFORDS
COMMA
MIGBODGE
GREDDY
RIPLEYS
EBAY

etc etc

[e301988325i]

EBAY

[Theo]

There are a fair few bits on there from ebay! There's also Comma oil in the gearbox, oh the shame!

[GeoffBob]

Sounds like you are about to have quite an adventure Theo. I'd be more jealous if the Ring were within reach. Living down here it's not even an option for me

If you were a snail you could have the letter "S" painted all over your car. Then when you get to the Ring everyone would say "Wow, look that S-car go!"

Sorry, that's so old is embarrassing

[Theo]

Taxi for GeoffBob!

[tomislav]

Hey theo, when you going to the ring?

Just interested cos me and a rather large group are going there 21st t0 25th may

[Theo]

The trackday is on the 19th April so I don't think our paths will cross.

[GeoffBob]

Only eight more sleeps to go Theo

Brake bias adjuster and prop valve all setup ok? Same compound pads front and rear? Happy with the M/C sizes?

DO bring yourself and the car back safely!

Best Wishes
Geoff

[Theo]

Thanks Geoff, plan is not to crash as I have to drive the car home. Bit of a gamble but I don't have a trailer or suitable tow car so there's not much choice.

The brake balance is excellent, you did a great job with all the calculations. The 'Ring has many varied braking zones (over 24km per lap with the GP Sprint circuit included) so a few tweaks on the bias adjuster will probably be in order. I still have the EBC yellows fitted front and rear which are lasting well although I fancy a set of Performance Friction 01's next time round, everyone seems to rate them as one of the very best pads.

Need to do a bit of preparation on the car such as teathering the front spoiler/splitter to the valance so it does bend downwards at high speed. A nut and bolt check is also in order, i'm reasonably confident nothing has fallen off though.

[Theo]

Good news - both the car and I are still alive, after an incredible trackday. The car was pretty much perfect and immensely satisfying to drive - I'm properly chuffed with it.

Driving down the hugely bumpy straight was fantastic, I actually laughed out loud the first couple of times - such were the severity of the bumps which I was going over at 150mph.

Here's a little pic which a friend took, had a great lap with that 993 behind, what a way to spend a monday!



I'm planning on a host of upgrades/maintenance/tweeks so may take the car off the road for a month or two - I really don't want to though..

[GeoffBob]

Glad you made it back safe and sound Theo! What an awsome time you must have had. I am absolutely green with envy!

Must say, the intercooler looks stunning poking out below the bumper like that

What sort of tweeks/upgrades do you have in mind?

Regards
Geoff

[Theo]

Sorry, Geoff but I had to gloat!

The intercooler does look cool, it has a nice collection of insects impaled on the fins now. Incidentally I was getting consistent intake temps in the low 30s (degree C) with an ambient of around 13/14 - Even after 50km of constant lapping....or in other words, 2 laps!

What sort of tweeks/upgrades do you have in mind?

The list is long, largely maintenance I suppose.


- Replace bonnet pins with plus flush aero catches
- Replace front crank oil seal
- Check steering rack for leaks and repair/replace
- Re-do a couple of areas of seam sealer
- Under seal over cage nuts on underside of floor pan
- Tap top hose adaptor to M14x1.5 and fit sensor/wiring for standard gauge
- Brace intercooler cut-out in front valance
- Make better engine mounts
- Fit banjo connection parts for clutch hose and re-bleed
- Get BOV working correctly
- Tidy up wiring in cockpit
- Lower the steering column another 10mm
- Perform compression test
- Refit bulb to right hand side of heater control panel
- Check condition of spark plugs
- Check accuracy of oil temp gauge
- Replace worn bearing on OSR coilover
- Make sure km/h speedo and 8k rev counter are reading accurately
- Fit breather filter to valve cover
- Fit more countersunk m8 bolts/nuts to front splitter
- Buy and fit missing nut/washer/seal for rocker cover
- Get matching passenger seat
- Fit high pressure oil switch
- Fit smaller battery and relocate to behind passenger seat
- Get car corner weights done again
- Fit exhaust heatwrap to turbo elbow and downpipe
- Fit Rocker arm stoppers
- Fit larger clutch slave cylinder
- Check condition of prop centre bearing
- Check exhaust system for blows
- Check condition of drive shafts

I'm also keen for some more power, so need to consider some bigger injectors, remap, bigger maf and a better turbo..

[Kos]

just a few things planned then

good to hear your car performed well

i did consider doing this track day as well, but i just had no time for it and other comitments but all but with all thats happened at heathrow i would have !!

[Theo]

Shame you missed out, but there looks like there's another one in August...

[GeoffBob]

Incidentally I was getting consistent intake temps in the low 30s (degree C) with an ambient of around 13/14 - Even after 50km of constant lapping

So that’s a Delta-T of around 15 to 20 ”˜C at thermal equilibrium (I’m pretty sure that 2-laps of the Nurburgring constitutes thermal equilibrium ). That really is very good Theo

The list is long, largely maintenance I suppose.

- Replace bonnet pins with plus flush aero catches
- Replace front crank oil seal
- Check steering rack for leaks and repair/replace
- Re-do a couple of areas of seam sealer
- Under seal over cage nuts on underside of floor pan
- Tap top hose adaptor to M14x1.5 and fit sensor/wiring for standard gauge
- Brace intercooler cut-out in front valance
- Make better engine mounts
- Fit banjo connection parts for clutch hose and re-bleed
- Get BOV working correctly
- Tidy up wiring in cockpit
- Lower the steering column another 10mm
- Perform compression test
- Refit bulb to right hand side of heater control panel
- Check condition of spark plugs
- Check accuracy of oil temp gauge
- Replace worn bearing on OSR coilover
- Make sure km/h speedo and 8k rev counter are reading accurately
- Fit breather filter to valve cover
- Fit more countersunk m8 bolts/nuts to front splitter
- Buy and fit missing nut/washer/seal for rocker cover
- Get matching passenger seat
- Fit high pressure oil switch
- Fit smaller battery and relocate to behind passenger seat
- Get car corner weights done again
- Fit exhaust heatwrap to turbo elbow and downpipe
- Fit Rocker arm stoppers
- Fit larger clutch slave cylinder
- Check condition of prop centre bearing
- Check exhaust system for blows
- Check condition of drive shafts

Oh, you mean jack up the windscreen wipers and install a new car underneath . But seriously, that’s quite a list (can see you have put some thought into what you want to do), should keep you out of trouble for a while.

I was interested to see that your BOV is on your list. It’s amazing how many people have BOV problems, and I have had my fair share too. Darn things never seem to work exactly as you want them to. I seem to recall you said you have your BOV under electronic control. I did the same with mine, but takes a bit of work to get the PWM signal to the solenoid to control the BOV exactly as desired (well, that was my experience, but I don’t nearly have enough experience to claim expert knowledge on this matter).

I'm also keen for some more power, so need to consider some bigger injectors, remap, bigger maf and a better turbo..

Could you possibly add a standalone management unit to that Theo? Would make your life so much easier than using the stock Nissan ECU. Would mean that you could get away from that MAF altogether in favour of a MAP based system. It’s a popular mod on the SR20DET. You’d be ill advised to program the ignition and fuel maps yourself (I still believe that a dyno is the best way to do this), but you could still implement other modifications yourself after she’s been mapped. I am forever fiddling with things like the rev-limiter, traction control, water-pump control, knock sensor, BOV control, and other bits on my Adaptronic ECU. All I have to do is plug in my lap-top and I am away. Just a suggestion.

The better turbo, to which you refer, would just have to be the GT2860RS Extremely popular on the SR20DET.

Regards
Geoff

[Theo]

Yes, it's a significant service I suppose! Thing is, the car has hardly changed since the day we got it running so the large number of tweeks are kind of inevitable.

My BOV isn't anything fancy - just a Greddy Type-S recirculated into the intake trunk after the MAF. I don't think I've ever heard the bugger 'blow off' I just get wastegate chatter, flames and bangs - I'm led to belive that this shouldn't be the case with a recirculated BOV.

With regard to the aftermarket ECU, I know it's a logical step but the standard ECU is proving so reliable that I'm inclinded to keep it - I see sooo many people having difficulties with aftermarket management. That said, I suppose this is down to poor installation/setup rather than inherant unreliability.

I'll look into the GT2860RS - I've also been recommended the GT2871, why would you favour the 2860?

[GeoffBob]

My BOV isn't anything fancy - just a Greddy Type-S recirculated into the intake trunk after the MAF. I don't think I've ever heard the bugger 'blow off' I just get wastegate chatter, flames and bangs - I'm led to belive that this shouldn't be the case with a recirculated BOV.

Sorry, thought it was yourself who had your BOV and wastegate under electronic control. I get confused communicating with so many different people. Flames and bangs you say? Hmmm, your Nissan MAF is a hotwire type, non? Any chance your BOV is blowing off backwards through your MAF? A hotwire airflow meter can’t tell direction (doesn’t matter which way air flows through it). If your intercooler is letting off a fair bit of steam back out through the MAF then it’ll fool your ECU into thinking you have a whole lot more air coming in than there really is. Hence your fuelling will run rich and she’ll pop and bang like mad. I honestly suspect this is what you have going on there.

With regard to the aftermarket ECU, I know it's a logical step but the standard ECU is proving so reliable that I'm inclinded to keep it - I see sooo many people having difficulties with aftermarket management. That said, I suppose this is down to poor installation/setup rather than inherant unreliability.

Definitely down to poor setup in my experience (or a cheap and cheesy ECU). Too many people don’t want to pay for dyno time and try to map them themselves. I prefer an aftermarket ECU for all the added features that you get.

I'll look into the GT2860RS - I've also been recommended the GT2871, why would you favour the 2860?

Oh no, the GT2871R would be an excellent choice. ”˜Has an identical turbine to the GT2860RS (both the 0.64 and the 0.86 A/R versions are available), but with a slightly larger compressor wheel.

[Theo]

I wouldn't have thought that charge is going backwards through the MAF - the standard Nissan setup is the same albeit with a different DV so you would imagine they have eliminated the possibility of this happening. I suppose I could check this by removing the recirc hose and blanking the port in the intake trunk and see if it still pops and farts.

I might look into an aftermarket ECU at a later date, at present I don't really see any requirement for it as I have no complaints over the Nissan management - I just want more ponies!

[crossie]

If you are off back to the nurburgring in August I ll book a lap out in your car now theo

[Theo]

Yeah no worries mate!

I'm tempted by the August trackday, a mate is having his stag do out there in early September though...