Story so far with hub dyno results for BW 91/79

Hi all

As well as putting up some info that some may find useful, I wanted to say a few thanks as well.

During the last few months I've had a few ups and downs while tryng to get my car mechanically sound so that I can get round to some cosmetic stuff, such as wheel refurb, etc.

The story with this car started two years or more ago. It went from a standard twin turbo VVTi to a single as soon as I got it. The turbo was a Garrett GT4088R on an SP manifold (I think) and at the same time this was being done all the new fuelling work, etc., was carried out, new 850 injectors, uprated pistons, rods and bearings, but nothing on the head. The ECU was an AEM.

All went well, for a while...

I had the same problems everyone else seemed to be suffering with the GT4088R - frayed blades. Upon seeing this happen, the manifold also decided to follow suit and promptly cracked around the runners and on the turbo flange.

After that I decided to leave it alone for a while as I had other things that needed my attention and I was also stinging from paying out a lot of money to basically have feck all to show for it.

Back in April I decided to try again, and this time I went for a BW 91/79 and Whiffbitz manifold, which Paul also fitted. I also decided to have the head done this time round and had Titan Motorsport cams fitted (272 9.9mm lift) along with Supertech valves, springs etc.

A Syvecs ECU was then supplied and fitted by Ryan and he then went onto map it. It produced 654BHP when it went on the the dyno at SRR, with about 540 ft/lbs.

The main thing I noticed when I first drove it was that it seemed laggy, quite a difference to the previous setup. Ryan had commented on this too. When I spoke to Paul and he saw the graph, he said it looked too laggy for the setup. Other people with the same turbo and manifold seemed to be getting useable boost around 4000 plus, mine wasn't really doing anything 'til about 4750 or so.

Anyway, a number of things were investigated to see if there were any obvious problems but nothing showed.

I then got the car to Chris Wilson, who had looked after my previous Supra, taking it from a standard UK to a really nice BPU setup. And having Chris only about 15 mins away is excellent.

During the time Chris had the car he did a lot of work to it, including fitting a new clutch, flywheel, idle control valve (needed because the idle was pretty crappy to be honest) plus a few other odds and ends.

Chris also fitted a new VVTi unit as the old one was making a knocking noise. Once the new one was on Chris dismantled the old one and found it had seized, definitely buggered.

One of the other bigger jobs he did was to re-do the valve clearances, and boy, what a difference that made! The car went from being noisy, harsh-sounding and seemingly stressed when being asked to perform, to being sweet, tight, more willing to get on with it, and all with lower EGT's.

Also, the oil temp now didn't go above 100 or so, even when pushing fairly hard, whereas before I could easily and quickly go over 110 and beyond. Everything seemed a lot, lot better.

After that we had a few electrical issues which caused a far bit of frustration to say the least. A couple of sensors were dodgy and got replaced but the main issue was tracked down to the wiring for the map sensor being severed. Once we sorted that, the ECU reported back that all was good and I set about booking a new mapping session.

Which brings me onto last Friday when I spent the day down at TDI in Thurrock getting the car mapped by Dave Rowe.

Some we did on the road but the real stuff was done on the hub dyno. What a setup that is - a fantastic dyno room with more fan-power than a Take That concert.

We were in there for three hours or so and I even managed to do my bit by sitting in the passenger seat pressing Alt R on the dyno keyboard when I got the thumbs up from Dave before each pull

The car went in running at 1.45 bar, making 654 BHP at the flywheel and 540 ft/lbs from when it was dynoed at SRR back in June.

It came out running at 1.75 bar, making 593 BHP at the hubs with 479 ft/lbs on Tesco 99.

Dave (mapper) and Sam (TDI) both commented that there was more power in there but a limiting factor seemed to be the wastegate spring, which was only .5 bar.

I was really pleased with the overall results and I'd like to thank Dave for a stirling job. It was great to work with him and see him in action.

One issue that cropped up was my intake temperature. A probe on the cold side of my filter was reading 56 degrees. It really pushed home how useful it could be to get the air intake boxed off from the hot air in the bay and fed with its own dedicated supply.

On the way home the car felt good. It sounded nice and pulled really well, wanting to break away at the back on a few occasions.

The lagginess is still there so it seems as if the cams are playing their part in that. But when it all comes on song, pulls hard and keeps going, they're probably playing their part in that too. I'd love to get a quicker spool and will look into possibilities.

So, a big thanks to the guys at TDI. Sean and Sam were highly professional and did everything they could to make the day as hassle and stress free as possible. Very knowledgable guys too.

Also, I need to thank Lee (SRD) and Jamie. Many times I've spoken to both on the phone and every time each has spent time talking stuff through and giving honest, real-world advice on a number of things. Thanks guys.

And Chris. I've now known Chris for quite a while and I think I've caused him as much frustration during that time as I have myself. Particularly with this most recent set of problems. But, he has always given me honest, straightforward, no-nonsense advice. There have been times I haven't listened, but I've suffered for it. And he's gone above and beyond the call of duty to help me when I've been in a hole, on more than one occasion during my time as a Supra owner. Thanks Chris.

Jules

How does that relate to Flywheel figures from SRR, just so the members can see the difference, at first glance and to the average guy it looks like you have had all that work done and lost HP, which is not the case.

Nice one Jules, glad its worked out.

How does that relate to Flywheel figures from SRR, just so the members can see the difference, at first glance and to the average guy it looks like you have had all that work done and lost HP, which is not the case.

He is now at about 685bhp up from 654.

Interesting that the torque figure is about 60ft/lbs less on the TDi dyno, since dynos only read torque and power is based on a calc.

Glad to hear it's all coming together.

Nice job, glad you got all your issues sorted.

654bhp at 1.45bar on SRR is very respectable anyway. I bet it feels great now

Thanks for the kind words Julian. You know me and electrics. Sorting the cam clearances and the VVTi is no biggie to me, but an ecu with no instruction manual and an interface that looks like pre GUI Linux is not something I go into confidently I am sure it's vastly capable, but to me it was hard work. Glad it all came together once I had fitted an idle control valve and you found the wiring break. My next goal is to get you take the damned thing on track, before you get locked up using 600 + BHP on the road Living where we do, with Oulton just up the road, and Donington having re opened for business it would be a crime not to get you making proper use of it, especially as it has new R888's on it. Enough power, now we need to make it stop and go around corners competently Thanks again, it was frustrating at times, but you are a joy as a customer and a nice guy to boot, so I don't mind.

Did Dave Rowe map the solaris then? I thought he was a motec only man?

Did Dave Rowe map the solaris then? I thought he was a motec only man?

I think he will map anything if he is paid, he prefers certain ECU's to others, he rates the F-Con funnily enough (almost don't want to get rid of it) and obviously Motec.

I think he will map anything if he is paid, he prefers certain ECU's to others, he rates the F-Con funnily enough (almost don't want to get rid of it) and obviously Motec.

Cheers!

Good to see/hear that he'l map anything.

Nice results well done.

I had to talk nicely to him, as he is so busy he is probably in the enviable position of being able to turn down any jobs that sound like potential hassle, but he did it! Ryan is away and Julian was getting frustrated now having an idle control valve and working VVTi, but no mapper.

I had to talk nicely to him, as he is so busy he is probably in the enviable position of being able to turn down any jobs that sound like potential hassle, but he did it! Ryan is away and Julian was getting frustrated now having an idle control valve and working VVTi, but no mapper.

Having now had a proper look at that graph and seeing power at the wheels go up by a factor of x 2.6 within 1000 RPM between 4000 and 5000 RPM all I can say is it will be handful in the wet

It is still very laggy, at 4000rpm its only making 180 ish rwhp, my big 76mm turbo makes 271rwhp at the same revs on the same dyno at similar boost.

It is still very laggy, at 4000rpm its only making 180 ish rwhp, my big 76mm turbo makes 271rwhp at the same revs on the same dyno at similar boost.

Isnt your 76mm a billet though Jamie?

Isnt your 76mm a billet though Jamie?

He is on a much smaller turbo, it should not be that laggy, something is not right imo.

It is still very laggy, at 4000rpm its only making 180 ish rwhp, my big 76mm turbo makes 271rwhp at the same revs on the same dyno at similar boost.

Yeah apparently those Precisions are shite eh JP !!!!!!!!

He is on a much smaller turbo, it should not be that laggy, something is not right imo.

Thats true, I need to get mine on a hub dyno for comparison as mine has similar lag

I haven't actually driven this machine of Julian's yet, he's offered me a go in it this week. Looking at the graph it wouldn't be to my liking for a road car, but on track it should be a beast given it's no proper LSD, very modest tyre sizes and knackered suspension I'd be putting a much smaller turbo on it if it were mine, and I was going to use it on the road. Do they do a smaller exhaust housing for the one he has, as a cheap test? I am not 100% about the cams, either. It just sounds a bit funny, almost as if the phasing of the cams is out, but they are timed up fine.....

I haven't actually driven this machine of Julian's yet, he's offered me a go in it this week. Looking at the graph it wouldn't be to my liking for a road car, but on track it should be a beast given it's no proper LSD, very modest tyre sizes and knackered suspension I'd be putting a much smaller turbo on it if it were mine, and I was going to use it on the road. Do they do a smaller exhaust housing for the one he has, as a cheap test?

It should spool much quicker on that turbo Chris, its 67mm iirc, i cant see it being cam related either, 272's would not make that much difference to lag time imo.

My money is on the turbo is knackered, was it ever inspected Jules?

The compressor wheel looks fine, it has no excess radial play or end float. Not sure about the exhaust wheel, never seen it. It's not one of those things that has to go back to the US for bits is it?

The compressor wheel looks fine, it has no excess radial play or end float. Not sure about the exhaust wheel, never seen it. It's not one of those things that has to go back to the US for bits is it?

AET supply them so shouldn't be an issue.

The compressor wheel looks fine, it has no excess radial play or end float. Not sure about the exhaust wheel, never seen it. It's not one of those things that has to go back to the US for bits is it?

BW turbos are pretty cheap, if there is something wrong with it i doubt its worth fixing, id like to see Jules get to the bottom of this lag problem as i know its been going on for a while, just throwing some ideas about:)

BW turbos are pretty cheap, if there is something wrong with it i doubt its worth fixing, id like to see Jules get to the bottom of this lag problem as i know its been going on for a while, just throwing some ideas about:)

I recall the repair kits are about £150 so surely cheaper to repair than replace, if its the tubby causing the issue.

Does this car have an open wastegate or is it plumbed back into downpipe, does the wastegate have a good seal when shut?

It was on an open wastegate, he's had it plumbed back into the downpipe now, but I don't believe Julian saw any difference. Anyone know what exhaust housings are available for it?

It didn't sound like it was leaking when it was on an open pipe. Can't remember what make the WG is, Julian may see this later.