Papercup's V8 RX7

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papercup

Original Poster:

2,490 posts

220 months

Saturday 17th July 2010
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Exhaust manifolds are lovely, all twisty and turny and different both sides:








and from undeneath:


papercup

Original Poster:

2,490 posts

220 months

Saturday 17th July 2010
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As mentioned before, we are keeping one of the Rex oil coolers for safety's sake on track. What the hell, its there right? The fancy thing i bought a while back (picture on previous page) that allows remote mounting of oil devices without using a sandwich plate is in and its all connected and working:





You can see the sensor for the oil pressure there:





and below it Craig has plumbed the oil temp sender in the sump



Edited by papercup on Saturday 17th July 19:20

papercup

Original Poster:

2,490 posts

220 months

Saturday 17th July 2010
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The rear end, with the auto diff i sourced, all fitted. It looks to be in good nick:



These are waiting for these to be fitted to brace it all up:



Edited by papercup on Saturday 17th July 19:22

papercup

Original Poster:

2,490 posts

220 months

Saturday 17th July 2010
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The standard power steering cooler is a bit pants, and takes up too much room. Better we use this dinky little thing. Its living where the other oil cooler usually is (the opposite side to the one we've kept) and it will share this space with the air filter...




papercup

Original Poster:

2,490 posts

220 months

Tuesday 20th July 2010
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Just sent the V5 off to notify change of engine number and cubic capacity smile

Spoke to Craig today; exhaust will be finished tomorrow, and the air-con guys also visit tomorrow to see whats needed to get it all working. The car now has an air-con pump from an early F-Body Camaro as the one that came with it from the Pontiac GTO has the pipes exiting on the wrong side.

papercup

Original Poster:

2,490 posts

220 months

Sunday 1st August 2010
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Had to go to a wedding oop north this weekend, so a perfect excuse to drop in and see Rex. Lots more progress has been made. In fact, if the ECU guy hadn't gone AWOL this week the car would be running. Hopefully by the end of next week it will be.

You may remember I am being difficult by not only insisting on keeping my pop-up lights (meaning Craig can't use his normal route for the air intake, and he needs to use a different radiator) but also insisting on working air conditioning. Craig has risen to this challenge, and how!

The pictures above from a few weeks' back show that we originally kept the passenger-side oil cooler but the intake has now gone over there, meaning Craig has now decided to switch to using the drivers' side instead (the Rex came with both). So now the little power steering cooler we saw a few weeks back has a bigger brother behind it!



You can also see the aircon radiator, which is mounted outside the diamond-cut ally panel that Craig had made, and that can be seen a few posts up, looking very obvious. Thats now been sprayed black to suit the rest of the car. You can hardly see it any more, as its not only the same colour as everything around it, but also is covered up by the aircon rad. The aircon rad will have its own fans.



Where the original oil cooler was is now full of K&N!



You can also see the radiator, mounted vertically, the first time Craig has done this. Its inside that front panel and has its own fan.



Here it is with the bumper on, so show how well things are hidden:



With the aircon rad being black, its a nice 'stealth' look from the front, whereas I was used to having a bloody great silver intercooler in the middle!



You can see that none of this hangs below the bumper, so there shouldn't be any ground-clearance problems:





And from the side. You can see in the distance where Craig has used flexi tubing to bring the intake under the frame rails, and you can see the how well everything has fitted:



The engine bay with the bumper fitted. So that aircon rad is completely within the bumper.



I like the tidy way each coil pack is on the head, right above its own plug:





The underneath is all done now. Here is passenger side at the front, with the oil pickup and filter visible next to the sump, with the new downpipe from the manifold fitted:





From further back, showing the downpipes meeting at the centre box.





From the back of the car:





Here is the rear of the car with all the bracing fitted for the diff.





And from the side:





...and the diff brace itself:





Last but not least, a rather poor (sorry frown ) picture of the dashboard with those previously mentioned and pictured new Stack gauges in the original holes. They are the two clean ones, one above the other!






Getting very excited now smile

Edited by papercup on Sunday 1st August 18:22

papercup

Original Poster:

2,490 posts

220 months

Wednesday 4th August 2010
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rhinochopig said:
Won't the aircon rad block the airflow to the engine rad? I would imagine it'll struggle to keep the engine cool when you start adding power - or are you planning on drawing air from underneath the car venting through out of bonnet vent?
I doubt it. Air-con-rad-in-front is the normal way, and its normally aspirated, no turbo to raise underbonnet temps too high. Two small fans on the aircon rad and a big one on the main rad will keep things under control i would think....

There is no bonnet vent; i've had to go back to the standard bonnet as the vents on mine hit the intake. I am very sad about this, I loved that bonnet weeping

Mine is missing the normal undertray but we are trying to source one. Apparently it makes a big difference to the temps; they are much higher without it. Too much air comes in the front and simply escapes under the car.

papercup

Original Poster:

2,490 posts

220 months

Thursday 5th August 2010
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just received the following pic from Craig; the air-con fans are on.

smile


papercup

Original Poster:

2,490 posts

220 months

Thursday 5th August 2010
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The car ran yesterday for the first time. The ECU came back from being unlocked and she started up. My dinky dry-cell battery from a Harley Davidson started it many times; good news! There was a question over whether it would be man enough. We'll see what its like when the car is hot; thats the real test apparently.

Its not right though; it starts and ticks over, but there is nothing from the throttle pedal; it doesn't do anything. Turn it off and it won't start again until you query the ECU and get some fault codes about programming. There is also, mysteriously, as I thought (or hoped) it was from a complete untouched production car, a sticker on the ECU saying 'remanufactured'. So maybe something wasn't unlocked or there's a glitch somewhere. The ECU guy is to visit today and wipe it completely, then install a base map from a UK 6-litre Monaro. We'll see what happens I guess.

Onward and upward......

smile

papercup

Original Poster:

2,490 posts

220 months

Friday 6th August 2010
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It runs smile

The ECU wipe worked, and she runs and ticks over and is driveable. Well, it would be if it had front wings and a bumper.

Next is tidying up, fitting the bodywork back on and driving it to the aircon place to get that all working. Once thats done we may attempt getting the full climate control working from a japanese Touring X model.

Soon....it will be mine!

papercup

Original Poster:

2,490 posts

220 months

Friday 6th August 2010
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the rotten sod just rang me and revved it down the phone.......wish i was there!

Apparently its all good, oil pressure nice and high, sounds fruity but is actually quite quiet. Sounds perfect.

So....when can i have it?

smile

papercup

Original Poster:

2,490 posts

220 months

Saturday 7th August 2010
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Costs Update:

engine and box etc - £5700
sump kit - £365
cam kit - £585
remote oil thingy - £80
gauges - £230
aircon fans - £190

= £7150

PLUS £3000 paid to Craig within a week or two of him starting.

= £10150

MINUS £3300 from the bits sold so far from the Mazda

Money spent so far: £6850.



Craig needs another £2000 from me to get to the £5000 agreed. Also, we agreed a price of £600-odd to get the aircon working. Also, he is doing some other bits and bobs for me (harnesses) and he really didn't want to do the 'dashboard out and swap the gauges' bit so there are some extras. However, I'll split this all out when the job is finished and do a 'normal' price for those just having the conversion, then outline the extra costs for aircon (around a grand I would assume) and other bits and bobs.

I did all this on paper at the start and assumed I'd have little change out of £12k. I was right, and the aircon and those few extras would just take it over. But all that money I spent on the nice bits in the engine bay of the Mazda have done me proud, so we are looking at around £9k out of my pocket for the whole thing.

Andy

papercup

Original Poster:

2,490 posts

220 months

Thursday 12th August 2010
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Picked it up yesterday from Craig's and paid him for the remainder of everything. I need to do an updated 'costs' thing as I had forgotten about a bunch of stuff. I went up with 4 grand and came back with six quid!

It sounds immense smile

Drove it around the block but its unmapped and was a bit of a pig, not ticking over, weird laggy throttle response etc so really all i did was chuck some fuel in it and take it back. I would rather wait until its mapped to give true indications of whats its like.

So...put it on the trailer and took it to Wortec in Chichester and left it with him last night. He's mapping it today and tomorrow. Should have it back saturday morning at which point I'll see if i can get a video or something up.

smilesmilesmile

papercup

Original Poster:

2,490 posts

220 months

Thursday 12th August 2010
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KB_S1 said:
Papercup,

wrt to a discussion on another thread regarding weight advantages of the original rotary engine, do you know how the centre of gravity is affected by the transplant?
not yet, but I'll be corner-weighting the car soon. I had planned to change nothing and do it, but we had to lift the front to stop it scraping on the floor. Bottom line; Its heavier.

I can't check CoG, only weight distribution. To do so utterly I will have to lift the rear coilovers by 5 turns of the collar as that is what we did on the front. Then i can tell you how much more it weighs, and whether its been added to the front or middle of the car. I am tempted to do this as I want to know. Then I'll set my heights and corner-weight properly. Then I'll get it on track and tell you how it feels. The rex was stunning under braking into a corner. Thats balance and low CoG and light weight. NOTHING I ever met on track beat me into a corner. Thats where I think this will matter.

I am not in any doubt this will make it a different car. That was the idea. Also, for what this has cost I could have rebuilt a rotary 3-4 times. People reading this need to realise that before they talk about the holy grail of cheap V8s etc etc. I've heard it all and argued against it on the rotary forum myself.

The fact is I did 4 years of over 400 horse in the rotary, and I wanted to do something different but I still love the Rex. This seemed like a good idea. I am under no illusion that it will be 'the same but better'. I think it will be different. I have always thought I'll be able to feel the change in weight, and weight distribution and I'll be documenting my thoughts utterly here as things progress.

Andy

papercup

Original Poster:

2,490 posts

220 months

Friday 13th August 2010
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Well, the clutch just let go during mapping. Ho hum. Both the mapper and Craig think this is great news ('it proves its making good power!' said Craig) but its a minor annoyance for me as it basically means the car is off up to Birmingham again.

So, production LS7 clutch is on its way to Craig's from Monkfish. £643 + £35 delivery (overnight, saturday). Ouch. Plus fitting.

Moral to this story; just put a clutch in it if you are straying a decent amount above standard power. Its easily done when the whole thing is in bits and will save money and time in the long run.

On a side note, the aircon, which we thought was leaking, is less cold today than it was yesterday (I told the mapper to leave it on to stress-test it). This proves the leak and the dye that Craig put in should show us where when its getting the clutch done. So it needed a return visit anyway.

Anyway, it stll drives OK normally and the mapping can be finished. Its only full-bore runs through the gears that show it up. I may drive it up there.

papercup

Original Poster:

2,490 posts

220 months

Saturday 14th August 2010
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Its immense smile

Picked it up from Paul @ Wortec's house last night. £580 for mapping. Time for another costs update i think!

Cold start isn't great, and needs another tweak. I didn't realise cold start was so basic; its just a percentage of throttle. Of course he's only cold-started it twice so hasn't been able to turn it up high enough. So it starts but you need to keep your foot on the pedal for just a minute or it will conk out. It is literally a minute though, then its good as gold. I'll run into him again soon and he'll add a few points more throttle to it.

Battery seems to be coping. Tiny dry-cell thing from a Harley-Davidson. Left on an Optimate most of the time as a rotary and never been any trouble before. Let me find a pic:



There ya go. I'm amazed it even turns it over. It does have trouble, it turns over slowly but always fires and mapper thinks i will need to be changed. We'll see. It had no trouble starting the car over and over again at Craig's. Hot start is the killer and only time will tell.

Ticks over at 960 rpm and sounds quiet in the car; perfect. Then you put your foot down and it sounds like it will tear out your heart. When i got home my girlfriend said it was rattling the windows in the house when i reversed up the driveway. He he.

Drives very well; mapper echoes what the people that sold the cam to me said; this is as far as you would want to go on the road. I actually expected worse. Its very civilised.

To be honest I am having trouble assimilating it. I've never driven anything like this. It really is like a different car. I drove it home from Chichester in heavy rain, in the dark, on Toyo 888s. Not fun really. Will swap on the other wheels with the road tyres on today, and fit the passenger seat.

Surprising traction; i expected first gear to be worthless. I did had a moment in 2nd gear. In a straight line. Its got some torque. The most immediate thing is the torque. You can just leave it in 4th in built-up areas. It pulls happily from 500rpm. It ticks over at 960rpm! You can drive it without any throttle; just let the clutch out and keep changing gear. It does about 35mph in top gear at tickover. I went through Worthing on tickover, giggling.

Then you put your foot down. Oo-err. It does go. The weirdest thing is cruising in top gear and put your foot to the floor. It feels like a jackhammer, thump, thump thump. In lower gear its over too fast.

Anyway, too much typing, not enough experience. Off out to fit passenger seat, change wheels and drive into town to see a mate at his shop. Possible pictures to follow.

Andy

papercup

Original Poster:

2,490 posts

220 months

Sunday 15th August 2010
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Left Front - 330.5kg
Right Front - 336.5kg
Left Rear - 296.5kg
Right Rear - 309kg

Total: 1272kg

Left 628kg - 49.3%
Front 667kg - 52.4%
Rear 606kg - 47.6%
Cross 633kg - 49.7%

Rear bite - 12.0

Weight is not an exact comparison; when i corner-weighted the rotary @ Re:Worx it had the Recaro SPG seats (4.5kg against the standard ones that are in now and have got to be 15kg each) and just under half a tank of fuel (against the 'just under three quarters' it had today). So.....10kg each seat and around 15 litres of fuel is about another 10kg or thereabouts.

Call it 30kg difference and we have a final figure of 1242kg. As a rotary it was 1186kg. So we've added around 60kg, or an 11-stone human, to the weight of the car. Not very much really is it?

I will have to dig out the original percentages and cross weights of the rotary corner-weighting. Fairly sure it was 50% side-to-side and 50% diagonal, and 51/49 front to rear. Will confirm later.

If so its a little more front heavy than it used to be, which is hardly surprising; the rotary was lower and completely behind the front suspension turrets and the V8....isn't. But it seems to handle; Max has two rotary RX7s and knows them well, and he was glowing when he got out from driving it. Very impressed. You could see the little cogs going round in his head.

I've done more miles in it today; I drove to Winchester (from Brighton) and back to see Max for the corner-weighting, and have just arrived in Birmingham to see Craig (the infamous Tinker-27 you see above) to have the LS7 clutch fitted tomorrow. I am starting to get used to the car now. Straightening the steering wheel made a big difference; its surprising how much it throws me to have the wheel at '2-o-clock' when going straight ahead. I've been pushing it harder through roundabouts and such today and am struggling to find a difference in the handling to how it was before. Its still sharp as you like. Maybe the track will show it up.

Max is right; the throttle pedal is way too sharp though, and wants turning down a bit in sensitivity terms. Very hard to modulate at low speed. The first inch of throttle is mental. The mapper said he could change it a bit; will have to get in touch. Fortunately he's not far from me in Chichester.

Air-con has given up completely now; not even worth turning it on any more. So it was leaking, and now its dead. The dye that Craig put in is evident in the engine bay so hopefully we can find the leak tomorrow and get it gassed up again. It needs it; its a hot car and driving it around in hot weather is uncomfortable. Its not as bad as when it was a rotary; then it used to get hot and smell of petrol and oil. This just gets hot and......gets hotter.

Got stuck in the usual traffic jam on the A27 in Arundel earlier and saw oil temps of 105c and water temps of 115c. Both Max and I think it will overheat on track. A re-think of the radiator set-up may be in order. More fans, different angle? We'll see - I'll discuss with Craig tomorrow.

papercup

Original Poster:

2,490 posts

220 months

Monday 16th August 2010
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redvictor said:
nice conversion..thumbup
I can see why the engine water is getting hot. The radiator needs a duct and shroud so that you're always pulling cold air across the whole face of the radiator. As it is now the air will escape around and under it. Just a heads up.
To be fair, this was crawling at walking pace in heavy traffic; thats not really an air flow issue any more, its a fan issue.

Today the LS7 clutch has gone in and we've found the (two!) leaks in the air-con. Tightened up the pipes near the bulkhead will hopefully fix that one but the compressor itself, a second-hand item, has.....had a catastrophic failure and is dripping fluid everywhere. Bugger. Again, I had thought of reconditioning it before we even started but thought it would be OK. That will be that hindsight again, biting me in the arse.

So the compressor has come off to be reconditioned and we've blanked things off for the moment. Also, to test cooling options, we've rigged up the two air-con fans on the air-con rad to the aircon switch so I can manually turn those on. So next time I am in traffic and it heats up I can switch those on and see if it makes a difference. Then perhaps we can ad more fans to the radiator. Or we can rig those aircon fans into the main cooling circuit and when the rad fan comes on they come on, independent of the aircon, but they also come on with the aircon when its switched on. Options, options!

Oh, and the spending continues. The worst thing about this conversion is the gearbox. I had heard this. Most boxes are either vague or notchy. This is both. Notchy to engage, but the middle point, from neutral to each gear, is like porridge. Its a bit crap really, not in any way positive. I have little idea what gear is coming next. So i sat in Craig's car and he has a 'ripshifter' quickshift and its like night and day. Positive, direct, still notchy but I don't mind that if you know where the stick is going. £300 plus VAT. Christ. For a quickshifter? Oh well, ordered and will be fitted when the aircon pump comes back.

As will the Tein bonnet struts, nice pneumatic thingies, anodised green to match my Tein coilover tops (I am a tart, sad but true). So i regretfully say goodbye to me old bonnet stick, and its broken plastic clips, that has done me so proud. Goodbye old friend. £115.

As for the bonnet; it lifts behind the headlamps in a worrying manner. At 90mph its an inch clear of the wings. I've seen the results of a bonnet catch letting go, and Craig has an Aristo in has workshop right now that did just that. Its a mess. So sleek bonnet catches are going on as we speak, Craig swearing in the background. £30-odd i think. Those and the Tein struts are coming from Driftworks who've moved in next door to Craig a few months back. Do they come with a luminous yellow 'doriftu' sticker? Lets hope so wink

Andy

Edited by papercup on Monday 16th August 16:31

papercup

Original Poster:

2,490 posts

220 months

Monday 16th August 2010
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RX7 mileage at engine swap = 79,800 miles.

papercup

Original Poster:

2,490 posts

220 months

Tuesday 17th August 2010
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tooFATtoDRIVE said:
papercup said:
Oh, and the spending continues. The worst thing about this conversion is the gearbox. I had heard this. Most boxes are either vague or notchy. This is both. Notchy to engage, but the middle point, from neutral to each gear, is like porridge. Its a bit crap really, not in any way positive. I have little idea what gear is coming next. So i sat in Craig's car and he has a 'ripshifter' quickshift and its like night and day. Positive, direct, still notchy but I don't mind that if you know where the stick is going. £300 plus VAT. Christ. For a quickshifter? Oh well, ordered and will be fitted when the aircon pump comes back.
Is this something like this one? http://www.rpmoutlet.com/gtosniper.htm

Also, have you considered something like a sequential shifter, something like Ikeya Formula Shifter type shifter for T56 transmission?
Yes and no. Craig had the B&M one at some point in the past and was not polite about it when I asked if there was a cheaper option. You get what you pay for, it seems.

The one in Craig's car was lovely, just what i want in mine. I don't really want anything too different.....just a nice gear-change!