My Spire GTR slow burn accountability/manmaths/badinfluence
Discussion
Late in 2024 I was looking at ND MX5s and went to drive a few but was considering other "fun cars" to replace my daily such as 987s etc. The girlfriends cousin has a Westfield Megablade and I've always taken the piss of my car searches saying I should just get a Honda Jazz and be done with it.
I've always fancied a kit car such as a Fisher Fury and even ordered a MK Indy kit in 2004 along with stripping a sierra down and buying a vauxhall red top. My dad kept saying how dangerous they were so I cancelled the kit, did a DAS course, bought an VFR400 NC30, then a Ducati 848 and commuted weekly Fleet to Barnstaple on a 5pw R1 before falling out of love with biking.
The girlfriend therefore quickly persuaded me to look for a "silly" car and have a sensible daily. I considered the usual Westfields and MK indy but didn't want a 7 style car and prfer the full bodied Fisher Fury. I thought a part built project was the way to go as they were usually cheaper and I could easily put my stamp on it but time will tell. So while bobbing around the Pacific ocean last autumn with non existent WiFi I purchased an unseen Spire GTR and had it delivered to the garage.
The kit was delivered new to a college up North and part built "badly" from what I can see and sat unloved before being bought by my seller during lockdown. I'm not sure where It was stored as some parts look brand new while the wrap looks very weathered and the chassis in the footwells is flaking its finish with corrosion showing. The bodywork has been cut badly around the chassis too.
Its currently set up for a zzr1100 engine with some badly welded mounts. I have a letter from Kawasaki showing the engine is pre cat so would only need a visual smoke test during IVA. Bit of a heavy and low on power engine these days though so am considering other options despite being initially keen. It has six RMD alloy wheels which makes me think some may be wider but not checked, wilwood calipers all round, wilwood master cylinders, a Davis Craig water pump and paddleshift levers among the two boxes of junk. Big spendy items required are seats, engine, exhaust, lights and potentially diff upgrades.
The elephant in the room is that I have my complete 5pw R1 bike that I've not ridden in ten years. It has 16000 miles, a Barnet spring clutch kit already and a PC3 (serial port version though). They were apparently really good in kit cars with only a sump baffle required. It was overheating before being layed up which I think is a blocked radiator so need to investigate. I've too much sentimental value to rip it apart though but could sell it to fund something else once I've sorted the cooling and put new chain and sprockets on it. Man maths required here.
Newer 1000s are putting out about 10-20 more bhp than the 5pw and have slipper clutches which I'm not sure I need so thinking of going with one of those. The zzr1400 appeals but weighs 40kg more than a 1000 which is a lot if I'm aiming for a car weighing 450-500kg. I'd struggle to lose that on the car without spending massive amounts of cash. On the left field a z1000sx makes similar power to the 5pw once tuned but a glob more low down torque. It was an "All new" engine design in 2013 but looks a lot like a zx9r engine so 80kg v the 65kg 1000s.
I'm busy looking for a k5 onwards gsxr1000, 2004-2013 zx10r or 2008 onwards blade in bad physical condition but mechanically sound. The Blade seems to be flavour of the month but the billet sump and third gear mods required pump the price up a fair amount verses the cheaper sumps of the others. I keep dreaming of it being Kawasaki green, blue and white which clouds my judgement. Or dog dick pink
Then there's the conundrum of using bike style engine orientation with a lighter home made (bodged Quaife ÀTB in a swinging adjustment frame) chain diff. It came with a prop of unknown quality and a 7 inch Sierra differential in the car. I have actually had the diff case off and it's a 3.62 open diff so may need to swap the crown wheel and pinion for a 3.38 and consider an LSD option while there. Bike orientation would mean I'd likely have to get a different shaped fuel tank too but less transmission losses, potentially better oiling prospects and an easier route for the induction. More maintenance though but it's a toy.
I guess I'm starting this thread for some sort of accountability so that I actually progress with then car. I've still not had a chance to look it all over so need a kick up bum every now and again. I also want to throw ideas around and get encouraged to do silly things with it.
Phew.
I've always fancied a kit car such as a Fisher Fury and even ordered a MK Indy kit in 2004 along with stripping a sierra down and buying a vauxhall red top. My dad kept saying how dangerous they were so I cancelled the kit, did a DAS course, bought an VFR400 NC30, then a Ducati 848 and commuted weekly Fleet to Barnstaple on a 5pw R1 before falling out of love with biking.
The girlfriend therefore quickly persuaded me to look for a "silly" car and have a sensible daily. I considered the usual Westfields and MK indy but didn't want a 7 style car and prfer the full bodied Fisher Fury. I thought a part built project was the way to go as they were usually cheaper and I could easily put my stamp on it but time will tell. So while bobbing around the Pacific ocean last autumn with non existent WiFi I purchased an unseen Spire GTR and had it delivered to the garage.
The kit was delivered new to a college up North and part built "badly" from what I can see and sat unloved before being bought by my seller during lockdown. I'm not sure where It was stored as some parts look brand new while the wrap looks very weathered and the chassis in the footwells is flaking its finish with corrosion showing. The bodywork has been cut badly around the chassis too.
Its currently set up for a zzr1100 engine with some badly welded mounts. I have a letter from Kawasaki showing the engine is pre cat so would only need a visual smoke test during IVA. Bit of a heavy and low on power engine these days though so am considering other options despite being initially keen. It has six RMD alloy wheels which makes me think some may be wider but not checked, wilwood calipers all round, wilwood master cylinders, a Davis Craig water pump and paddleshift levers among the two boxes of junk. Big spendy items required are seats, engine, exhaust, lights and potentially diff upgrades.
The elephant in the room is that I have my complete 5pw R1 bike that I've not ridden in ten years. It has 16000 miles, a Barnet spring clutch kit already and a PC3 (serial port version though). They were apparently really good in kit cars with only a sump baffle required. It was overheating before being layed up which I think is a blocked radiator so need to investigate. I've too much sentimental value to rip it apart though but could sell it to fund something else once I've sorted the cooling and put new chain and sprockets on it. Man maths required here.
Newer 1000s are putting out about 10-20 more bhp than the 5pw and have slipper clutches which I'm not sure I need so thinking of going with one of those. The zzr1400 appeals but weighs 40kg more than a 1000 which is a lot if I'm aiming for a car weighing 450-500kg. I'd struggle to lose that on the car without spending massive amounts of cash. On the left field a z1000sx makes similar power to the 5pw once tuned but a glob more low down torque. It was an "All new" engine design in 2013 but looks a lot like a zx9r engine so 80kg v the 65kg 1000s.
I'm busy looking for a k5 onwards gsxr1000, 2004-2013 zx10r or 2008 onwards blade in bad physical condition but mechanically sound. The Blade seems to be flavour of the month but the billet sump and third gear mods required pump the price up a fair amount verses the cheaper sumps of the others. I keep dreaming of it being Kawasaki green, blue and white which clouds my judgement. Or dog dick pink
Then there's the conundrum of using bike style engine orientation with a lighter home made (bodged Quaife ÀTB in a swinging adjustment frame) chain diff. It came with a prop of unknown quality and a 7 inch Sierra differential in the car. I have actually had the diff case off and it's a 3.62 open diff so may need to swap the crown wheel and pinion for a 3.38 and consider an LSD option while there. Bike orientation would mean I'd likely have to get a different shaped fuel tank too but less transmission losses, potentially better oiling prospects and an easier route for the induction. More maintenance though but it's a toy.
I guess I'm starting this thread for some sort of accountability so that I actually progress with then car. I've still not had a chance to look it all over so need a kick up bum every now and again. I also want to throw ideas around and get encouraged to do silly things with it.
Phew.
This looks like an interesting build, a bike engined car is always a cool thing. Just out of interest, is the zzr1100 engine from a ‘C’ model or even earlier? I know they can be tweaked for a little additional power, but it still might not make what you’re looking for - nice an torquey though (for a bike engine anyway 
)
Keep us updated!
)Keep us updated!
darkyoung1000 said:
This looks like an interesting build, a bike engined car is always a cool thing. Just out of interest, is the zzr1100 engine from a C model or even earlier? I know they can be tweaked for a little additional power, but it still might not make what you re looking for - nice an torquey though (for a bike engine anyway )
Keep us updated!
It's a 1991 engine so a "c" model and were restricted from the factory meaning a could replace the carb tops for ZXR 750 ones to go from 125-150bhp. )Keep us updated!
My girlfriends cousin has persuaded me to go for a fuel injection engine so have been doing some serious man maths and making graphs of power curves etc.
I think I want to go light as I can afford which rules out the busa, zzr etc as the 1000cc engines weigh 30-40kg less. I'd struggle to make that up elsewhere on the car without spending some serious money. I also don't want to have a dry sump or accusump if I can't help it.
I'm interested in a non usual engine at the moment and have been on the gear calculation websites. The engine seems to have a shorter first gear than the usual 1000cc bikes and the upper gears are more spaced out.
Gear calculator shows the following speeds per gear for it using a diff ratio I could use:
47.71012804
65.24625065
81.55781332
99.46074795
116.418766
135.9296889
70mph would be 5700 in sixth
The first four gears are similar to a gen 1 hyabusa on a 3.62 diff but the busa tops out at 120 on the calculator and does 70 at 7500 rpm.
I may be wrong in thinking that this would have decent acceleration plus more relaxed road manners at cruising speed? All of the 1000cc sports bike engines do 60 in first gear and I'm unsure how important that is.
I guess I'd be better off using a common engine but this uncommon one has a semi dry sump (1x feed pump and 3x scavenge pumps internally) and revs the same amount as a 5pw but makes more power and torque everywhere onto a claimed 170bhp and 125Nm. Weighs the same too.
The engine also has DBW and modern electronics which would be impossible to use the standard ecu. This has led me down the aftermarket ECU rabbit hole and think I'm keen to follow it to get engine control, wideband O2 auto tuning, flat shift, auto blip and potential for TC at a later date. Stupid bonus of cruise control is a possibility as well.
Another option is a GSXS1000 engine with a K7-8 head and cams on it. Later engines have DBW and the crank/block is the same as a k7-8 but cheaper to buy with low miles than the gsxr.
I spend ages making spreadsheets with power and torque graphs of various engines on them and charts of gear ratios. At one point I was determined to put a Ducati Multistrada v4 engine in there with chain drive to get decent gear ratios. I even mocked up a v4 engine using cardboard from technical drawings.
Anyway I have an engine winging it's way to me as we speak. It's a Japanese 4 cylinder and I'm keeping it simple keeping the sierra diff set up and fuel tank. The gearing will allow me to get away with my 3.62 diff for the time being. I'll also be able to paint it ZXR green,white and blue.
It's a Kawasaki Versys 1000 engine from 2024. Has a mighty 118bhp, slipper clutch and DBW. The DBW is useful for the sporty features such as flat shift, auto blip and I fancy cruise for some perverse reason. If it blows then a replacement engine is £400-700 instead of £2k.
Your notice it's low on power but that's where it gets stupid again. It's actually a low compression z1000 engine. The sleeved down low compression engine in the z900rs goes from 100hp to 215bhp with just 10psi of boost on standard internals.
I'm away with work for a few months now and have loads to work out when away. Turbo choice and sump modifications being the two big ones
Anyway I have an engine winging it's way to me as we speak. It's a Japanese 4 cylinder and I'm keeping it simple keeping the sierra diff set up and fuel tank. The gearing will allow me to get away with my 3.62 diff for the time being. I'll also be able to paint it ZXR green,white and blue.
It's a Kawasaki Versys 1000 engine from 2024. Has a mighty 118bhp, slipper clutch and DBW. The DBW is useful for the sporty features such as flat shift, auto blip and I fancy cruise for some perverse reason. If it blows then a replacement engine is £400-700 instead of £2k.
Your notice it's low on power but that's where it gets stupid again. It's actually a low compression z1000 engine. The sleeved down low compression engine in the z900rs goes from 100hp to 215bhp with just 10psi of boost on standard internals.
I'm away with work for a few months now and have loads to work out when away. Turbo choice and sump modifications being the two big ones
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