Grief Update - Clive F 180° Crossover Equal Length Manifolds
Discussion
Most TVR owners will be familiar with Clive Ford’s stainless master pieces in the form of his popular manifold Y Piece. Last year Clive surpassed himself and created a tuned crossover manifold system, the same design as seen on the legendary Ford GT40 that somehow fits under the bonnet of a Griff.
So what is the point of a crossover manifold? The issue with a conventional 4-1 exhaust header is the separation between exhaust impulses. With a 90° (cross plane) crankshaft 2 exhaust pulses exit through the collector at the same time. A crossover manifold pairs the correct cylinders that fire 180° degrees apart in their firing are paired together, maximizing scavenging. When one cylinder is on the compression stroke, the other is on the exhaust stroke resulting in a constant flow, thus creating equally spaced exhaust pulses.The result is similar to that of a 180° (flat plane) crankshaft with four evenly spaced exhaust pulses in each header.
I had managed to resist the temptation of Clive’s latest masterpiece until I bumped into fellow Griff owner Peter Billington at the Griff Growl last year. Peter has a immaculate, sensibly modified Griffith and had just completed fitting the crossover manifold system. Peter very kindly offered to take me out for a spin in his to demonstrate the new manifolds and I was sold. The sound was incredible, a cross between a RV8 and Cerebra with the howl of a GT40 higher up the rev range…. epic! A few weeks later Clive received an order.
I am still running the OEM Lucas 14CUX ECU on my Griffith. I asked Clive to build the manifolds with two narrowband lambda sensor bosses (one per bank) for the 14CUX and two wideband lambda sensor bosses for a future expansion (aftermarket ECU). I also asked for a wideband lambda sensor to fitted where both banks merge to allow me to run an AFR gauge at a later date.
Running the 14CUX with this system does pose an issue in that the lambda sensors in standard configuration read from cylinders 2,4,6 and 8, and 1,3,5 and 7. With the crossover manifolds fitted the sensors read cylinders 1, 4, 6 and 7, and 2,3,5 and 8. The 14CUX is bank fired so to correct this it is a simple case of extending the injector wiring so injector wires 3 and 5 are swapped for 4 and 6.
Changing manifolds on a TVR is always a time consuming job due to the lack of access to the bolts. 2 long evenings later the manifolds were fitted. The water pipe to the radiator was rerouted underneath the chassis rail and I took the opportunity to fit a JE alternator bracket to replace the tensioner.
First impressions are very good. The car seems to rev much more freely and the sound is unbelievable. Very happy indeed.
Video - https://youtu.be/IrLgSyt47A0
The car went to Dom at TVR Power for a service in March, while the car was in I asked him to put the car on the dyno for a power run to check the AFRs and also see what difference the manifolds made.
2016 Dyno Result
275.17BHP & 295.93ftlb at the wheels.
TVR Power dyno reads in wheel figures so I have converted to flywheel figures using the below site, I appreciate this is not an accurate method but it helps give a rough comparison with the usual dynos which read at the flywheel.
http://www.mk5cortinaestate.co.uk/calculator4.php
BHP – 324BHP
Torque – 348ftlb
2017 Dyno Result
274.52BHP & 301.77ftlb at the wheels.
BHP – 323BHP
Torque – 355ftlb
Peak torque is up a bit but I am mainly impressed by the healthy increase in bottom end torque. The result is certainly promising but the car is running rich compared to last year so not really a fair comparison without a remap. There will certainly be more come with an adjustment on the fuelling and the addition of mapped ignition.
Very nice. Regardless of numbers I bet it's faster.
What a sound, you can't really get better than that.
It would be marvellous if you could make it to Shakey Matt
It would make a great video for the sound alone.
That's a serious investment but after awhile sound is one of the best parts about these cars. You've got that covered then
Is this with a standard exhaust system, can't remember !
What sort of decibel level do you estimate it to be at the rear. ( trackdays)
For the craic,, and I'm hoping to dip into the 12's I'm going full decat and fully sleeved for the Shakey weekend, it will be loud I know that
Our cars were well matched and my power graph is very similar until 4000 revs then your off and gone it would make a great race, you should be pulling away at the end and the better spin up should have you edging it on acceleration too.
I'm sure once you've re mapped it it will be better again, Mbe would sort you out for good!
Just saying
Takes time, years and your achievements are a testimony to your good choices.
This is on an old engine too, how many miles has it done.
Mega car.
What a sound, you can't really get better than that.
It would be marvellous if you could make it to Shakey Matt
It would make a great video for the sound alone.
That's a serious investment but after awhile sound is one of the best parts about these cars. You've got that covered then
Is this with a standard exhaust system, can't remember !
What sort of decibel level do you estimate it to be at the rear. ( trackdays)
For the craic,, and I'm hoping to dip into the 12's I'm going full decat and fully sleeved for the Shakey weekend, it will be loud I know that
Our cars were well matched and my power graph is very similar until 4000 revs then your off and gone
it would make a great race, you should be pulling away at the end and the better spin up should have you edging it on acceleration too. I'm sure once you've re mapped it it will be better again, Mbe would sort you out for good!
Just saying
Takes time, years and your achievements are a testimony to your good choices.
This is on an old engine too, how many miles has it done.
Mega car.
Matthew Poxon said:
I am still running the OEM Lucas 14CUX ECU on my Griffith. I asked Clive to build the manifolds with two narrowband lambda sensor bosses (one per bank) for the 14CUX and two wideband lambda sensor bosses for a future expansion (aftermarket ECU). I also asked for a wideband lambda sensor to fitted where both banks merge to allow me to run an AFR gauge at a later date.
Running the 14CUX with this system does pose an issue in that the lambda sensors in standard configuration read from cylinders 2,4,6 and 8, and 1,3,5 and 7. With the crossover manifolds fitted the sensors read cylinders 1, 4, 6 and 7, and 2,3,5 and 8. The 14CUX is bank fired so to correct this it is a simple case of extending the injector wiring so injector wires 3 and 5 are swapped for 4 and 6.
MattRunning the 14CUX with this system does pose an issue in that the lambda sensors in standard configuration read from cylinders 2,4,6 and 8, and 1,3,5 and 7. With the crossover manifolds fitted the sensors read cylinders 1, 4, 6 and 7, and 2,3,5 and 8. The 14CUX is bank fired so to correct this it is a simple case of extending the injector wiring so injector wires 3 and 5 are swapped for 4 and 6.
I respect your tenacity and attention to detail, like also dumping the Disco alternator bracket, and your videos with lap times etc are very professional.
Sounds like you’re right about swapping over 3 and 5 injector wires for 4 and 6. I’m sure you realise you can buy male fuel injector (junior timer) plugs to make up injector extension leads that could easily be removed if required.
http://www.ebay.co.uk/itm/AMP-2-Way-MALE-Junior-Ti...
http://www.ebay.co.uk/itm/Fuel-injector-plug-conne...
I hope to see & hear your Griff again soon
The out dated 14CUX fires the injectors in alternate banks like Emerald and not all at once. While running closed loop the drivers side lambda probe output is used to adjust the fuelling only on cylinders 2,4,6,8 as the 14CUX effectively runs two independent closed loops. However, Matts drivers side lambda probe now receives exhaust from 2,3,5 & 8 and therefore injector wires 3 & 5 needs to be swapped so 2,3,5 & 8 are all injected and controlled together. Works in theory but we’ll have to wait and see.
Edited by stevesprint on Sunday 7th May 17:54
Thanks all for the comments , very kind. I will get an in car video up at some point, the sound is unreal. For those who asked questions please see answers below:
Trackdays is a good question, idle seems to be quieter but you get to 3k and teh sound really kicks in. Probably need to get it tested before booking anything up. I am hoping the bolt on cans will take enough off for me to contiune to play on track.
bluezeeland said:
Sincerely wish I hadn't read this..........anyway, your assumption of flywheel figures must be about right, reference is made to Sprint some months ago, the loss in the drivetrain is roughly 45 BHP ?
Also noted you do not run extenders or heat shields for the leads ?
Hi Frank hope you are well. You cannot see the extenders in the photos but they are there. Either ceramic leads or heat socks are on the radar. My extenders are working fine at the mo and I get distracted with shiny things!Also noted you do not run extenders or heat shields for the leads ?
TV8 said:
Any idea why the car was running rich?
Not sure, it was running OK last year so I assume the 14CUX has not compensated correctly for the new manifolds. Will need either a remap or a new ECU I to get the best I would imagine. GlynMo said:
That exhaust system is pure automotive porn. I'd fit one too, but the car would never pass its French MoT.
Although, can I be arsed? It's only once every 2 years to swap it back to the original. Mmm, ponders.
Having fitted the system I would say probably not, but then I am useless with a spanner. Sound is epic though so maybe worth the agro. Although, can I be arsed? It's only once every 2 years to swap it back to the original. Mmm, ponders.
ClassicChimaera said:
What sort of decibel level do you estimate it to be at the rear. ( trackdays)
Takes time, years and your achievements are a testimony to your good choices.
This is on an old engine too, how many miles has it done.
Mega car.
Thank you very much Alun, very kind of you sir. We have both done similar with our cars, build them up with a few cheeky upgrades as and when we can afford the over a long period of time. Good luck at Shakey, unfortunately I will not be able to make it. Engine has done 57k.Takes time, years and your achievements are a testimony to your good choices.
This is on an old engine too, how many miles has it done.
Mega car.
Trackdays is a good question, idle seems to be quieter but you get to 3k and teh sound really kicks in. Probably need to get it tested before booking anything up. I am hoping the bolt on cans will take enough off for me to contiune to play on track.
to all the above 
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