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About MaxDiesel

  • Rank
    IB Glitterati

Profile Information

  • Location
    West Sussex

Previous Fields

  • Current 911
    1987 Carrera 3.4 in Diamond Blue Metallic, 1973 Porsche 914 1.7
  • Favourite Food
  • Drink?
    Good red wine

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  1. Cheers Jevvy - I was a little sceptical myself but the guy at CBX seems to know his stuff and was happy talk me through exactly how he'd do the cleaning - definitely vapour only which explains why is not cheap...
  2. Tempting... but my aim is to keep the engine bay looking original - so I'm sticking with the 1.7 D-jet injection - which I'm sure would seriously limit the benefit from going any bigger. I dropped the crankcases off at this place for vapour blasting (http://cbxvapourblasting.co.uk/) - its going to be interesting to see how they turn out. The guy had a impressive mix of classic bike and car bits in for cleaning - the finished stuff looked great. Into the measuring and checking phase now. Started by cc'ing the heads Then worked out the piston dome volume by setting the piston a fixed height down the bore and subtracting this volume to get the dome cc This all confirmed the CR was just over the 8.2:1 in the spec book. The 1911 kit has flat top pistons and I think the same compression height - with the new bore size plugged into my spreadsheet I get ~9.3:1 so I'm still going need to tweak the head volumes to get to my target 9.5:1 - this can be done when they're machined for the large bores. Also finished stripping the crank - got the gears pulled off and rods off - all looks to be in good condition: Journals look like new - just need to borrow a micrometer and double check diameters Time to start ordering some new bits 🙂
  3. MaxDiesel

    Triumph ITB conversion

    Excellent - great work
  4. Bit more progress on the engine this weekend - had a closer look at the bores and the rust marks & pitting from when it stood for many years is worse than I originally thought: I think this is the excuse I was looking for to go for the 1911cc kit 🙂 Spent a tedious couple of hours degreasing and pressure washing all the tinware - can't get over just how much there is on a type 4 engine. This lot is off for blasting and powder coating next: Due to the rust marks on the bores and likely increase in bore size I thought I better pay it safe and check the bottom end too..... All seems fine apart from loads of black sludge in sump. More degreasing and pressure washing... Crank journals look fine There's a place nearby that does vapour blasting - I'm going to see how much they want to the the heads and case halves
  5. I'd spotted the 123 ignition kit - they do one specifically for the Type 4 engines with the injection pulse trigger built in. A colleague of mine has one fitted o his highly tuned Midget and says it works very well with all the other mods he's got. I've seen some guys in the US have managed to get D-jet injection to work with bigger capacities - they've done this by adjusting the fuel pressure regulator and manifold pressure sensor - which I guess makes sense. It'll mean either fitting a Lambda kit or spending some time on a rolling road. Fortunately the rust seems localised to the hell hole and a bit on the jack points - the floors are completely solid unlike others I'd looked at. I'll be taking a deep breadth and cutting back until I get to something solid - going to need to practice my welding as its been a few years! I was aware the 2.0l head had bigger valves - I hadn't realised they changed to 3 stud inlet flange - I guess this means 2.0 heads must have 2.0 inlet manifolds which I'd want to avoid. I used to have a '68 912 many years ago and it was pretty sedate. I ended up rebuilding this as a fully balanced high compression 1720 with mild cam and Weber 44IDFs - this reliably gave ~115hp which was enough to make it fun as it didn't weight as much as a 911. They other thing the makes the 1911cc kit tempting is the price - less than a tenth of the cost of the Mahle 3.4 P&C on my 911! Think I might get stuck into the hell hole rust next and depending on how that goes make the call on bigger P&C.
  6. Cheers Henry - I'm in a quandary re engine mods - for just £350 I can get a set of pistons and cylinders that'll take it from 1679cc to 1911cc (VW tuning parts bin benefit). Looking how restrictive the inlet system is I'm not sure how much additional power this will give and probably more significantly it'll take it away from original... also it would probably be the start of another slippery slope - soon to be followed by new inlet, fuel injection etc etc. like I've done on my 3.2 3.4.... So far I've found nothing wrong with existing P&C to use as an excuse to replace them 🙁 I think my plan A is just to increase the compression ratio from the existing 8:1 (for US fuel) - probably go for ~9.5:1 if I can get this by reducing the volume in the heads. I'm hoping this along with some matching of manifolds and ports etc. might get an extra 10hp or so. That's a very good point - I'm about to embark on a load of welding in my new wooden shed..... I think a fire extinguisher might be a very wise investment!! Some more bits taken off tonight - pistons and rings are in remarkably good condition. There's some strange 'shadows' in the bores which I think are stains from where the pistons didn't move for many years. Going to measure the cylinders next - assuming OK then give them a light hone.
  7. I found there's lot of 'stuff' to come off a type 4 engine - most of which was held on by stubborn tinware screws.... And the D-Jetronic fuel system Finally something that looks like an engine: I've just taken the heads off and worked out why cylinder 2 was low on compression - a slight bend in valve head meant it was only sealing around two thirds of the seat: And the corresponding ding in the piston I reckon this happened after the car had been stood for 30+years - someone must have just cranked it without turning it over by hand first - the valve had probably seized with old fuel residue and carbon and then got slammed back by the piston Going to get the cylinders off next - there's some signs of historic corrosion at the bottom of the bores but otherwise they don't look too bad.
  8. I've made a start on the car over the last week - it took about a day to get the engine out - quite different to the 911 with various cables and rods running right to the back of the car. Pretty sure its the first time the engine's ever been out the car. Fortunately my 911 engine cradle works with a couple of timber packing pieces: Got to have a proper look at the infamous 'hell hole' under the battery tray - not a pretty sight as expected: I don't think you're meant to be able to do this... I've got the engine into the other garage so I can get it stripped down - 911 engine stand adapter fits the Type 4 engine fine:
  9. Long overdue update on my 914 project and its new 'shed' home: I finally got the car registered in August after sending the DVLA two further forms of dating evidence - one from Porsche and one from PCGB. I drove it around for a couple of months and put ~200miles on it - more than its done since 1979! Its great fun to drive - surprisingly comfortable and rattle free - just spoiled by one cylinder being very low on compression - so I decided to concentrate on getting the shed finished so I can get on and get the engine out. As I end up doing most my car projects over winter I thought I'd better insulate the shed - I spent two tedious weekends cutting Celotex sheets to fit the studwork: Then another three weekends lining the whole lot with plywood: Finally - lots of white paint to make it a bit less gloomy!
  10. MaxDiesel

    Triumph ITB conversion

    I'm wasn't really suggesting one side would be loose - it would still be a torqued up nut on the side with the slightly enlarged holes (by say +0.5 or +1mm). By using the right type of washer you can maintain a pre-load that should allow some slippage if required. I'd be concerned the X frame will fracture prematurely after a being stretched and and compressed a few times - even if its only by a fraction of a millimetre.
  11. MaxDiesel

    Triumph ITB conversion

    Not sure how much expansion there will be - but there'll definitely be some and it could generate some significant forces. I think this is why the inlet manifolds always tend to have a rubber union somewhere between the two sides - the 3.2 manifold is a good example. If it was me - I'd keep the fixing holes for the x-frame tight on one side - make that your reference for positioning and set up. Then make the holes on the other side slightly oversize - using something like a belleville washer would keep this side tightly secured but hopefully allow some movement as things expand and contract (they're unlikely to do this uniformly).
  12. MaxDiesel

    Triumph ITB conversion

    Looks great One thought I just had looking at that picture - your cross frame for the throttle linkage (the black aluminium 'X') is tying the two sets of throttle bodies together. I'm just wondering how this will cope with the thermal expansion across the engine as it warms and cools - i.e. when the heads move apart from each other - you could end up with some force going into the throttle assemblies, or the frame might fracture. I'd be tempted to build in some minimal compliance at the fixings either end - this could be just elongating the holes in the frame by ~0.5mm each and then using bellville type washers under the nyloc nuts.
  13. I made up a couple of kits to check fuel pressure a few years back - one using a regular pressure gauge and another using a spare oil pressure sensor. With the oil pressure sensor I moved the existing pressure sensor wire over so I could read the pressure on the dash while driving. As far as I recall its a very similar fitting to the fuel filter solid pipe i.e. flared steel pipe and cap nut. There's a ball bearing under the blanking cap sealing on the conical seat in the rail fitting Gauge version 1: I'm pretty sure I used diesel fuel line and cap nut to make this Version 2 using a spare oil pressure sensor wired into the dash gauge: There's some more details here: https://www.impactbumpers.com/forum/index.php?/topic/12376-32-full-load-running-problem/& I'm pretty sure I've got both these in a box somewhere in my garage loft if you get stuck and want to borrow them.
  14. MaxDiesel

    3.2 Carrera Fuel injector Alternative

    There's some more here that might be worth checking out: Although the static flows are quite similar (Q-stat) the dynamic flows (q-dyn) vary more - this is what you'll see in the car for the same ECU signal (as far as I know these numbers are mass of fuel flowed for a 1000 impulses of 2.5 millisecond duration).
  15. MaxDiesel

    3.2 Carrera Fuel injector Alternative

    Specs for those injectors below - the one ending 158 is the original OEM injector. Flow rates are all very similar when tested at the same pressure (300kPa) - the 360 and 364 are a couple of percent higher - the spray angle is slightly wider on these too.