‘78 6200M-TT LS3 Twin Turbo
Discussion
Hi all, thought I’d share a bit of my (mostly) COVID build LS powered ‘78 3000M.
Car has been done for a fair old while…not that these sorts of things are ever truly finished are they.
Basic spec is a 1978 3000M which was an OD equipped car which was a useful bonus as it turned out.
Original plan was an LS1 (5.7) with a cam which morphed into a supercharged LS2…which wouldn’t fit without hacking the bonnet a lot so Turbo was the chosen route. For packaging & response purposes smaller twin turbos were chosen. Then an LS3 came up so that was basically the final iteration engine wise.
I went for a BTR S2 Turbo cam, matching valve spring package & pushrods. I swapped over to LSA pistons which have a lower compression ratio & built it back up with ARP head bolts.
Driveline was fairly basic with a T56 initially which I swapped over to a T56 Magnum following some transmission issues on the dyno. Clutch is a twin plate McLeod which works well.
Turbos are fairly small GT28s with external Turbosmart wastegates. Custom twin 2.5” stainless exhaust with screamers.
Custom prop, Salisbury PowerLok with a tall 2.88:1 ratio.
Nissan GTR rear hubs/outer joints, custom 300M shafts with diff converted to 930 CV joints.
Unique front suspension setup, flanged bearings, custom wishbones in CDS. AP 4 pots with 325x30 front discs, rear disc conversion with hydra mech calipers.
Mishimoto custom rad, custom intercooler, Davies Craig EWP, custom alloy fuel tank with internal Walbro 525 pump.
Emerald M3DK6+ with custom harness, relocated coils, wide and setup & Haltech IC7 dash.
Revolution Rally wheels 7.5 & 8x17 in custom offset to suit.
Full rewire, re pipe, bespoke heater & ventilation. Cobra RSR seats.
Surprised how well the powertrain fitted, very little fabrication required. It weighs 1084Kg with 1/2 tank of fuel so is quite lively.
Massive thanks to Craig @ DynoTorque for lots of guidance, answering of silly questions & lots of “can you just” welding of stuff!
Car has been done for a fair old while…not that these sorts of things are ever truly finished are they.
Basic spec is a 1978 3000M which was an OD equipped car which was a useful bonus as it turned out.
Original plan was an LS1 (5.7) with a cam which morphed into a supercharged LS2…which wouldn’t fit without hacking the bonnet a lot so Turbo was the chosen route. For packaging & response purposes smaller twin turbos were chosen. Then an LS3 came up so that was basically the final iteration engine wise.
I went for a BTR S2 Turbo cam, matching valve spring package & pushrods. I swapped over to LSA pistons which have a lower compression ratio & built it back up with ARP head bolts.
Driveline was fairly basic with a T56 initially which I swapped over to a T56 Magnum following some transmission issues on the dyno. Clutch is a twin plate McLeod which works well.
Turbos are fairly small GT28s with external Turbosmart wastegates. Custom twin 2.5” stainless exhaust with screamers.
Custom prop, Salisbury PowerLok with a tall 2.88:1 ratio.
Nissan GTR rear hubs/outer joints, custom 300M shafts with diff converted to 930 CV joints.
Unique front suspension setup, flanged bearings, custom wishbones in CDS. AP 4 pots with 325x30 front discs, rear disc conversion with hydra mech calipers.
Mishimoto custom rad, custom intercooler, Davies Craig EWP, custom alloy fuel tank with internal Walbro 525 pump.
Emerald M3DK6+ with custom harness, relocated coils, wide and setup & Haltech IC7 dash.
Revolution Rally wheels 7.5 & 8x17 in custom offset to suit.
Full rewire, re pipe, bespoke heater & ventilation. Cobra RSR seats.
Surprised how well the powertrain fitted, very little fabrication required. It weighs 1084Kg with 1/2 tank of fuel so is quite lively.
Massive thanks to Craig @ DynoTorque for lots of guidance, answering of silly questions & lots of “can you just” welding of stuff!
Edited by StewB_v6 on Friday 5th September 13:04
Edited by StewB_v6 on Friday 5th September 13:07
I can’t remember the rear disc size - I think they’re around 280mm solid & the hydra mech calipers are VAG parts. The front calipers were originally intended for Lotus Evora S I believe. I fitted an adjustable bias valve in the rear brake circuit too plus braided lines & all new hardlines obviously!
Heat is a big consideration…
Exterior wise I’ve gone to the slimmer GRP bumpers in place of the original and extremely heavy foam rubber items.
LED headlights (the more classic looking central light bar type with upper & lower pockets rather than the projector style which don’t really suit older stuff to my eyes at least), tail lights & markers / repeaters.
Blacked out various bits, some of which could do with doing nicely.
I made a new dash panel as all of the ancillary gauges were replaced with the Haltech dash. Trimmed various bits to match the seats that are black vinyl with blue & green tartan inlays.
Also went to Ford column switchgear with a custom column shroud as the scattered controls over the dash drove me mad.
Also went for a Classic Nardi steering wheel, rebuilt pedal box with a different clutch master & adjustable stop to suit the T56 concentric clutch setup.
Some functional changes like a bespoke GRP battery box in the footwell trimmed to match.
Exterior wise I’ve gone to the slimmer GRP bumpers in place of the original and extremely heavy foam rubber items.
LED headlights (the more classic looking central light bar type with upper & lower pockets rather than the projector style which don’t really suit older stuff to my eyes at least), tail lights & markers / repeaters.
Blacked out various bits, some of which could do with doing nicely.
I made a new dash panel as all of the ancillary gauges were replaced with the Haltech dash. Trimmed various bits to match the seats that are black vinyl with blue & green tartan inlays.
Also went to Ford column switchgear with a custom column shroud as the scattered controls over the dash drove me mad.
Also went for a Classic Nardi steering wheel, rebuilt pedal box with a different clutch master & adjustable stop to suit the T56 concentric clutch setup.
Some functional changes like a bespoke GRP battery box in the footwell trimmed to match.
Edited by StewB_v6 on Friday 5th September 15:34
lolI think the term that gets used is “adequate”.
Suffice to say it matches the original Essex peak for torque at around 800rpm & power at around 1400rpm which is just after it starts to make boost. By 2k its multiples of the original power & torque peak.
Similar power to weight as a Mc P1 but it’s very docile & tractable.
Suffice to say it matches the original Essex peak for torque at around 800rpm & power at around 1400rpm which is just after it starts to make boost. By 2k its multiples of the original power & torque peak.
Similar power to weight as a Mc P1 but it’s very docile & tractable.
What a great build!
I'm running GTR (r32 to r34) 32 splined hubs too on a LSA supercharged Chim as the offset is the same as to the ford, plus aftermarket off the shelf twin caliper brackets for a 350z rotor and calliper set up.
Did you go with the "drive shaft shop" outer stubs to 930 cv? Their giving me grief with stub play in the hub!
I'm running GTR (r32 to r34) 32 splined hubs too on a LSA supercharged Chim as the offset is the same as to the ford, plus aftermarket off the shelf twin caliper brackets for a 350z rotor and calliper set up.
Did you go with the "drive shaft shop" outer stubs to 930 cv? Their giving me grief with stub play in the hub!
Nothing hugely inventive. Ford column stalks to put headlights, wipers, indicators, horn & main beam all onto the stalks (can’t remember if they are Mk3 Capri or Mk2 Escort…both very similar anyway).
As mine was a slightly older (‘77 I think) it still had the Triumph steering column with the lower leg abusing steering column lock/ign switch. I did look at going to the later column but they were surprisingly difficult to come by when I was doing the build. Fabricated an aluminium shroud which I rather crudely trimmed in vinyl which is now slowly untrimming itself…
Centre switches are Ford 1970s, there are a couple of spares in there to allow for other stuff. Then there are heater control, fan & traction control level switches which are Rover group rotary switches. There is also the controller for the Davies Craig EWP which is not brilliant as it doesn’t actually fit anywhere & has the connector on the side…quite what they are thinking with that I don’t get. It’s the one piece of the build I will most likely revisit as I’m not convinced by the pump or the controller. I’ll most likely go to the more OEM style Pierburg PWM controlled unit - only issue is packaging space. We shall see.
Did some custom graphics for the dash & head unit to tie it all in.
|
As mine was a slightly older (‘77 I think) it still had the Triumph steering column with the lower leg abusing steering column lock/ign switch. I did look at going to the later column but they were surprisingly difficult to come by when I was doing the build. Fabricated an aluminium shroud which I rather crudely trimmed in vinyl which is now slowly untrimming itself…
Centre switches are Ford 1970s, there are a couple of spares in there to allow for other stuff. Then there are heater control, fan & traction control level switches which are Rover group rotary switches. There is also the controller for the Davies Craig EWP which is not brilliant as it doesn’t actually fit anywhere & has the connector on the side…quite what they are thinking with that I don’t get. It’s the one piece of the build I will most likely revisit as I’m not convinced by the pump or the controller. I’ll most likely go to the more OEM style Pierburg PWM controlled unit - only issue is packaging space. We shall see.
Did some custom graphics for the dash & head unit to tie it all in.
ATM said:
I've met Craig. Good good guy. He did some work on my e46 with LS1 that he helped build with the PO.
Have you driven anything like this?
Yep Craig is a top banana. There’s an article on him / DynoTorque in this months EVO magazine actually.Have you driven anything like this?
E46 with an LS1? Yep have driven a few different LS converted cars although not for any real duration other than my own.
StewB_v6 said:
ATM said:
I've met Craig. Good good guy. He did some work on my e46 with LS1 that he helped build with the PO.
Have you driven anything like this?
Yep Craig is a top banana. There’s an article on him / DynoTorque in this months EVO magazine actually.Have you driven anything like this?
E46 with an LS1? Yep have driven a few different LS converted cars although not for any real duration other than my own.
My e46 was good but not great. My main gripe was the gearing mismatch between the Chevy type engine and box to BMW diff. It was even a lowish ratio diff compared to other BMW.
Ah ok, yep TVR has been on the road for several years now. Yep all good, dominated by the engine obviously but functions like a normal car. I would probably go for a less aggressive cam if I did it again but other than that it’s fine. It bimbles around quite happily & is savage when you poke it, that being said it’s easy to moderate & can just smear tyres if that’s what you’re after!
Diff ratios are always a subjective one - I went for a 2.88 in this one as it’s a relatively big motor in a light car so will easily pull it. I’ve got the “close ratio” version of the box which has the lower 5th & 6th, I think it has taller 1st & 2nd too but can’t remember without checking. The older Monaro type T56 has the 0.50 6th & shorter lower ratios which isn’t really ideal.
The LS3 certainly has more torque than an LS1…more of everything really so is more tolerant of gearing.
I know Craig generally goes for 3.15 diffs in most of the BMW stuff he does which works really well. It’s always a compromise although the 8HP conversion does seem to provide a broader solution with more ratios & a torque converter to plug the holes!
Diff ratios are always a subjective one - I went for a 2.88 in this one as it’s a relatively big motor in a light car so will easily pull it. I’ve got the “close ratio” version of the box which has the lower 5th & 6th, I think it has taller 1st & 2nd too but can’t remember without checking. The older Monaro type T56 has the 0.50 6th & shorter lower ratios which isn’t really ideal.
The LS3 certainly has more torque than an LS1…more of everything really so is more tolerant of gearing.
I know Craig generally goes for 3.15 diffs in most of the BMW stuff he does which works really well. It’s always a compromise although the 8HP conversion does seem to provide a broader solution with more ratios & a torque converter to plug the holes!
Gassing Station | TVR Classics | Top of Page | What's New | My Stuff