Griffith 500HC exhaust manifolds....

Griffith 500HC exhaust manifolds....

Author
Discussion

Harvy500

Original Poster:

285 posts

17 months

Tuesday 20th June 2023
quotequote all
Me again, would my Griffy 500HC have cats built into the exhaust manifolds or has it only got just below the Y pipe joint?
Many thanks in advance.

rigga

8,752 posts

208 months

Wednesday 21st June 2023
quotequote all
Yes there are cats on each side
Just after the primary pipes converge.
Then the main dustbin one in the y piece.


Unless someone has removed them previously.

Harvy500

Original Poster:

285 posts

17 months

Wednesday 21st June 2023
quotequote all
Thanks for that.
I've no idea if they've been hacked out yet.
Work and moving home are taking up all my spare time.
The car will be sent off to powers soon to get the MBE system installed and a couple of other snazzy parts.
I'm not trying to create a race car or try to build the fastest 500 out there. Just want it reliable and more responsive than it is now.
As work starts and progress is happening I'll post it.
As I'm a new poster, the system won't let me post piccys for 2 weeks. So that's about 10 days before I can show you the car as it is as a starting point.

Classic Chim

12,424 posts

156 months

Wednesday 21st June 2023
quotequote all
The engine better be in good nick before Dom will commit in my experience.
The good thing is once he’s looked over it you’ll know exactly where you stand as he will tell it as it is.
MBE on a good engine and road train is excellent though. Really excellent smile


Harvy500

Original Poster:

285 posts

17 months

Wednesday 21st June 2023
quotequote all
The engine has a full service history from when new.
Car had every fluid you can think of (diff, gearbox, engine etc) in the last few months.
The car was fully checked over by Fenhurst TVR in Sussex before it's MOT in April and flew through and I've got a receipt from Fenhurst in April for £5,700 for a major refresh.
New shocks, new brakes, new wishbones all round, new fuel pump and lines etc etc....
Loooong list of new parts.
I'm 100% confident the engine and drive train is great.
Car had a full respray end on last year.
It's the interior that lets it down.
Full retrim, carpets and dash being done by Central TVR after powers have waved their wand over the engine.
It's arranged, powers finish, collected by Central when done, when they're done, back to me.
Cars going to be away for 6-8 weeks but after that, it's just a very easy tidy up under the bonnet.
Chassis is good. Full outriggers done just before the respray.
Oh, what I paid for the car makes it a bargain even after powers and central have been at it.

Classic Chim

12,424 posts

156 months

Wednesday 21st June 2023
quotequote all
That’s sounds great to me.
You won’t be disappointed and you’ll gain lots of reliability for your money.
I had new battery cables and the like and in fact that was the point of my post as it should come back truly sorted for years to come.
Exciting times.
The wiring loom alone around the engine can withstand motorboat engine use it’s so effective.
I seem to remember MBE made looms for that very application.
Edited by Classic Chim on Wednesday 21st June 13:37


Edited by Classic Chim on Wednesday 21st June 13:38

Harvy500

Original Poster:

285 posts

17 months

Wednesday 21st June 2023
quotequote all
Yes, I'm told the car will get a full new engine wiring loom..
MBE does away with the pesky stepper motor, dizzy with the rotor arm, coil going as it's driven by electronic ignition and coil packs.
Uprated Bosch injectors (same as Volvo S60r). New maf..
Allegedly way smoother, better on fuel (yeah right) and 150% more reliable.
It's going to get an 885 cam while it's there and have ACT de pre cat manifolds and a y pipe decat but I'll keep the original y pipe cat.
I'm told it will transform the car but so far nobody's commented saying they've had it done and described exactly what transformation means or how transformation feels. Lol.

Classic Chim

12,424 posts

156 months

Wednesday 21st June 2023
quotequote all
It does just what it’s designed to do.
Replaces/ removes virtually all trace of most of the unreliable aging parts that usually show themselves when hot and cause umpteen running issues.
That’s a major transformation because possibly for the first time you feel like the car will not let you down.
More precise use of advance timing and better atomisation with modern injectors should see the car have more usable power and the torque curve more linear.
I wouldn’t say you have more power but the car will feel sharper and more responsive and throttle control more readable, easier to use.
Your induction noise becomes more roar and louder which is always a good sign.
My 450 Chim with Doms 885 cam using MBE but no ported inlet or bigger heads aka 5.0 engines, so the same as 4.0 engines posted a 12.6 for the 1/4 mile on a drag strip which is faster than most 5.0 cars will muster. A standard car will struggle to get under 14 seconds
My engine after Dom rebuilt it has around 345 ft of torque using MBE which is very respectable indeed and on par with a good 5.0 car.
My car was once 28th fastest car on the TVR 1/4 mile leaderboard which considering the highly tuned cars I was up against is also more than respectable.
I’d imagine your car might get to nearer 12 seconds so a very fast TVR indeed.
The clock doesn’t lie so your car should be faster with more torque and crisp firing and feel more urgent at just about any revs. I noticed straight away more torque and I can manoeuvre on tickover which is very useful and keeps you off the clutch at slower speeds which is a god send.

You will have so much torque you’ll barely touch the throttle and indeed should return better fuel figures but i’d say that’s marginal on the bigger ported 5.0 engines.
I have ran my car on both Catted and de cat Y pieces, more Hp de cat but torque feels broadly the same.
My car was mapped and rolling roaded by Dom and Jason at Powers Catted and emissions are extremely low. The car regularly smelt of unburnt fuel even Catted before MBE but now barely a whiff of anything out the tail pipes.
Many a Tvr leave two black circles on whatever’s behind them on start up… soot.. none of that nonsense prevails.
It’s a clean burn type of feel to the car.
The response from the engine from throttle inputs should feel pin point accurate and hence much easier to detect slip angle and deal with it with a tiny lift or throttle adjustment.
If your good at toe and healing on down shifts you can Rev match with great accuracy so yeah it’s transformative in many ways though most of them subtle changes.
I think using Map sensor rather than Maf offers better info on absolute air pressure being drawn in so better fuelling and timing characteristics can be employed.

Ive had MBE coming up to 8 years now and been through a complete body off job since it was installed and the car instantly fired into life and settled after rebuild, it fired in a matter of about 5 seconds. Its been through harsh winters and under 6 inches of snow and still fired up as normal. -10 degrees I seem to remember. Very impressive. It’s also been stood for at least 6 months while I was busy doing other things and other than the alarm immobiliser giving up the car again starts instantly. I did about 10,000 miles after it was initially installed though 3000 of those were within the first month as I collected the car from Dom and went straight off to the south of France.
So far it’s been bullet proof and I just love how much tidier and sharpe the engine bay looks without the Dizzy, leads and coil cluttering things up.
As for no stepper motor. That’s heaven to me.
The car sounds fantastically tuned is probably the best way to describe it.






Edited by Classic Chim on Wednesday 21st June 22:59

Harvy500

Original Poster:

285 posts

17 months

Wednesday 21st June 2023
quotequote all
Thanks so much!! That's getting me more excited!!
Problem.....it's like being a child on Christmas Eve but Christmas Eve feeling will last 6-8 weeks!
I live in deepest darkest south east Kent.
Anyone near my part of the world?

Classic Chim

12,424 posts

156 months

Wednesday 21st June 2023
quotequote all
Harvy500 said:
Thanks so much!! That's getting me more excited!!
Problem.....it's like being a child on Christmas Eve but Christmas Eve feeling will last 6-8 weeks!
I live in deepest darkest south east Kent.
Anyone near my part of the world?
I was once like that after I knew I was getting an American bicycle for Christmas. It was the summer and those months were the slowest of my life.
Such a good feeling though.
Do come back and keep us informed and some pictures when it’s all done.
Goodluck.

Harvy500

Original Poster:

285 posts

17 months

Thursday 22nd June 2023
quotequote all
Wildo Sir.

Belle427

9,736 posts

240 months

Thursday 22nd June 2023
quotequote all
Going aftermarket management set up properly is the single best thing you can do to these cars.
Should be a beast when it's all done.