Project Thread Supercharged Cobra Harrop TVS 1900

[Cobber]

Well I cant keep the secret anymore.

Over the last 4 years I have been building a weekend warrior cobra replica. My original engine was going to be a boring Ford 351 until I saw another cobra with a supercharged 1UZFE (Cobra on this forum) I was hooked and knew from then what my power plant was going be.

The build started with a front cut removed Celsior 1UZFE & R154 gearbox. I then sourced a donor Jaguar XJS V12 for the suspension. A Cobra chassis and body kit was then purchased from G Force sports cars here in the West.

The project took another 3 years to get to where it is today.

The car was originally NA due to wanting to get things like the suspension dialed in and also get a good feel for how the car handled and drove.

Specifications

G Force Chassis & body
Jaguar modified front & rear suspension
QA1 adjustable springs & shocks
Jag power lock diff 3.31:1
Std un opened 1UZFE
R 154 gearbox
Harrop TVS 1900 supercharger 75mm pulley (11psi)
Richwood manifold (ported)
1 3/4" extractors
Side pipes
Bosch 044 fuel pump
Std fuel reg
8 x 7MGTE 440cc injectors
Adaptronic ecu
Traction control
Launch control
Dual fuel & timing maps (lean cruise & power)
17" Pin drive Halibrad wheels
Tyres
315x35x17 rear
245x45x17 front
Weight with driver and 1/2 tank of fuel
1170 kg
49% front
51% rear
corner weight 50 50
0 - 60 unknown due to clutch slip
Top speed unknown due to not having big enough nuts

I built this entire car in my spare time and between work commitments so there was some periods of dead time during the build. All of the stainless components I fabricated my self with basic hand tools in the shed. I also had to teach myself all about efi as I had always played with carbs and dizzies before. I originally wired up the Lexus ecu but with plans for some boost later I soon moved on to something a bit more programmable.

Driving the beast

The Harrop TVS is just about silent when on the car and under boost, somewhat of a let down really but I think I would rather have the stealth approach.
Power wise it is beyond my expectations and is frightening just how quick this thing goes now.
I have only street tuned it at the moment and probably wont bother with a dyno tune as I am more than happy with how it's running. I am running air fuel ratios in th mid 12's at the business end and it pulls like a steam train on steroids right through to 7,000 rpm. The air temps are considerably lower than the M90 even with higher boost levels. The air temps even come down at higher rpm probably due to the higher air flow. I have no signs of detonation and I'm basically running the same timing map as when it was NA, some timing is pulled due the the higher air temps but not much.

Next jobs on the list is for a lighter flywheel and heavier clamp clutch.
Paint will be next winter after the summer fun as it is still in white gel coat, picking the colour is probably the hardest part of the whole build so far.

http://www.youtube.com/watch?v=Vl0gYCHU_yk

 

[MX73 V8]

OMG. that is super kewl!!!

Thats essentially the same engine setup i am planning for my supra!

 

[JustenGT8]

Very nice Cobber, all the more so for the home build aspect. It's gonna haul once you get the clutch sorted.

I'd still suggest a tune. If it's close (and sounds like it is) it won't set you back much and will be the icing on the cake. plus you'll know in a controlled setting that it's safe. UZs are strong and will take alot of punishment, i should know , but they aren't indestructible.

 

[drifty325i]

Thats awesome, so jelous of your supercharger setup as well

 

[scotturnot]

Very nice!, Cant wait for a new clutch so we can see some numbers on the bad boy!

 

[Cobber]

Thanks guys,

Justen, I think your right on the tune mainly for my peace of mind so it will go on the dyno when I have got the clutch sorted. The clutch slips on acceleration so strapping it down on a dyno at this stage is a bit of a waste of time. I have run data logs of the AF ratio on several runs now and it all looks very safe. I also need to find somebody in Perth I can trust with my baby.

Dyno sheets will be posted when the clutch is done.
I'm looking at a lightened flywheel and a 10" Nissan 350Z clutch set up.

 

[cribbj]

Andy that's a gorgeous setup there, and the Harrop looks super clean.

Kudos to you for staying the course.

Now, try not to kill yourself driving that beast!

 

[spf_lexus]

Now "THAT" looks fun to drive... How's she sound with those sweet side exit exhausts?

 

[Zuffen]

I'd like to see you get cold air into that pod filter as you could drop intake temps by 30 or more degrees and either gain some power or at least improve the survivabilty of the engine.

It looks very slick.

 

[Cobber]

Thanks John,

I don't ever want anyone to say he died doing what he loved (unless it's in a bed full of nymphomaniac cheer leaders).

It is a wake up call to me on just how quick things can happen and a whole new level of respect when driving. It's a bit frightening just how powerful you can make a car that can be driven on normal streets.

Now where should I inject the N2O pre or post supercharger?

 

[Cobber]

SPF, Follow the link in the first post and check out my youtube drive in the hills for the exhaust note.

Rod, Thanks for the comments. The pod filter picks up cold air from the bonnet scoop that is directly over the supercharger and is only 8 c higher than ambient when driving along. If anything I will make an air deflector plate on the underside of the bonnet to send the air more directly to the filter if need be. The delta T on the supercharger is very low I have only seen around 50 c temperature increase from pre to post air temps at around 9 psi. As the boost / rpm goes up the temperature goes down. Highest air temp which probably has a bit of heat soak onto the sensor in the back of the lower manifold is 90c. I have set up a fuel trim based on air temp as well.

I agree remote mounting the pod filter will drop the air temps but I'm not chasing ten tenths of power.

 

[Tuf Lux]

Turned out sensational Andy! Like I said before, absolute work of art, combining the old school muscle and tough lines of the cobra with the newer little rocket of a powerplant blown lexus v8 just seems to work so well. Not to mention you are using one awesome supercharger there, haha. Now all we need is for some more of you guys here to join our lil TVS huffer club and experience just how good they really are!