MOT reqirements with a LS transplant into a pre-cat car

MOT reqirements with a LS transplant into a pre-cat car

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FactBV

Original Poster:

358 posts

229 months

Monday 28th February 2011
quotequote all
I am sure I found the answer in one of my searches but now I can't find the thread.
If you put a moden LS engine in say a pre-cat griff, does the emission / MOT requirements stay at the 1991 / 92 level or become the same as a new car because they relate to the new engine (assuming that you use a new engine).

Thanks

Peter

EggsBenedict

1,787 posts

179 months

Wednesday 2nd March 2011
quotequote all
I don't know the exact law on this, but I will give you practical experience. I changed a Pinto engine that was in my 'D' registered Dax Rush for a Zetec that would have been catalysed in its old home. Come MOT time there was no cat test for it.

I do know that if you put an old engine in a newer car that should be catalysed, so long as you have evidence that the engine pre-dates the catalyser required year, then it should be MOT'd for emissions as for the year of the engine, not of the car.

FactBV

Original Poster:

358 posts

229 months

Wednesday 2nd March 2011
quotequote all
EggsBenedict said:
I don't know the exact law on this, but I will give you practical experience. I changed a Pinto engine that was in my 'D' registered Dax Rush for a Zetec that would have been catalysed in its old home. Come MOT time there was no cat test for it.

I do know that if you put an old engine in a newer car that should be catalysed, so long as you have evidence that the engine pre-dates the catalyser required year, then it should be MOT'd for emissions as for the year of the engine, not of the car.
Really helpful, thanks. Anyone else had similar experience?

macdeb

8,553 posts

260 months

Wednesday 2nd March 2011
quotequote all
I can only guess that it would go on the year of the chassis. Just a guess.

Boosted LS1

21,198 posts

265 months

Wednesday 2nd March 2011
quotequote all
Pretty sure it's the chassis. So a 1980 car has to pass emmissions from 1980 whatever engines fitted, lol. That's cool. With kit cars they try to use a carbed block that just have to pass a smoke test hence the sbc being popular.

FactBV

Original Poster:

358 posts

229 months

Wednesday 2nd March 2011
quotequote all
Boosted LS1 said:
Pretty sure it's the chassis. So a 1980 car has to pass emmissions from 1980 whatever engines fitted, lol. That's cool. With kit cars they try to use a carbed block that just have to pass a smoke test hence the sbc being popular.
Thanks. I was actually thinking about whether I could run it on carb(s) rather than FI, although I appreciate the limitations of that.

FactBV

Original Poster:

358 posts

229 months

Friday 4th March 2011
quotequote all
Speed eight said:
Hello.
I haver a letter from DVLA which I got a few years ago now about my SBC Tuscan year 2000 car.
The letter states that the MOT test should take the year of the ENGINE as the test base line.
So NOT the chassis, but the engine is the base line.

Regardless of carbs or efi. So for me this is a very easy test to pass as my engine BLOCK, which is pre 1986 by "DESIGN", ( not reality ) is the base figure to aim at. Regardless of the fact that I run a sequential efi system ontop of it. And that the block is a custom derivative of the pre 1986 DESIGN.

This has been the case for 5 years now and 5 MOT test centres.

Regards.
Speed eight.
Speed eight

Thanks for the contribution, I have also been reading your previous posts with interest, they are very well written.

To be honest, I was hoping that it was the car / chassis rather than the engine.

Just a question though; if your original log book says 4.0 litre and the engine capacity increases to 6.0 litres plus and you write to the DVLA, do they actually ask you 'have you had a different engine fitted or has the original been modified / bored out'?

If they just accepted the increase in capacity with no questions asked and you took it to the MOT station I am sure that they would just MOT it based on the chassis. I was wondering whether you had pushed for the letter so that you could have increased emmissions in a later car?

However, I guess that with all the money involved in the modificaion you would want to do it all properly anyway.

FactBV

Original Poster:

358 posts

229 months

Monday 7th March 2011
quotequote all
Speed eight said:
Hello Peter.
Thank you for your kind words.
So you want to use the LS in your 1991/92 Griff, yes?

The LS efi is very simple to hook up. Is there a real problem to use the LS with efi in the Griff and that is why you prefer a carb?
If that is that case then look at the sbc option.
Despite the myth that the sbc is as heavy as a tank........that is not so.

Go to www.SummitRacing.com and look up part number MLL-BP3834CTCI
This is a genuine 420hp & 450ftlbs motor ready to run! At $4000.00 that is around £2460.00 plus shipping and tax.
This will be rated as a pre 1986 motor for MOT testing. And will pass regardless of what you do to it.
I assure you that these power figures are very, very scary in a TVR.
You can not buy cheaper power than this.


Your assumption about the log book/DVLA and the MOT test are correct............BUT...........your insurance company will not be so.
They will ask for ALL modifications including the origin of the new engine, ie, what car is it from.
Adrian Flux who insure my car are CHEAPER than what a standard Speed Six costs me. Go figure that one.

Regards.
Speed eight.
Really helpful thanks.

I sold my last pre-cat Griff, but this time around was interested in finding perhaps a basket case and building a car to my taste, which I have been researching for a while. The problem is it always ends up in Aston territory price wise. I am tending towards the idea of an ‘old school’ look; clean uncluttered engine bay, big V8 on carbs, distributor etc. so felt that the pre-cat Griff was a good basis (emissions OK for the carb, no cats but note your earlier comments re the age of the engine). It is also cheaper than a 500 all things being equal.

I was looking at the LS as I did not want to start again with the design work required as some good experience has built up with the LS conversions in the Chim / Griff with some commercial propositions emerging from various people.
However, to be honest the SBC option does sound good, it’s not for the track and 400 bhp / 400 lb ft plus of torque would be way quick enough. The costs do sound very appealing as well. Just a thought, can you move the position of the distributor drive from the rear of the engine, not sure that it would fit in a Griffith installation.
I will go back again and re read your original thread, use of the TKO etc. and also have a read up on the SBC engine.
Thanks again.

PS. By coincidence, I was a Loss Adjuster in a previous life so the concept of Uberrima fides (‘utmost good faith’) is indelibly etched on my mind!


dbv8

8,665 posts

225 months

Monday 7th March 2011
quotequote all
Interesting stuff.

The cost of driving the car in normal circumstances was part of my considerations when i decided to go the full monty nitrous route.

With subtle(ish) NA modifications to my 450 i expect to have a car that will still do 25mpg + driving to events and cruises etc.
But when required i can have a choice of lets say + 100 bhp for those overtaking procedures on the road and i am aiming for + 300 bhp to keep up with the big engined conversions at the strip.

Granted i will possibly be using 4 bottles of nitrous through a good weekends drag racing which comes to over £200 eeklaugh

FactBV

Original Poster:

358 posts

229 months

Monday 7th March 2011
quotequote all
Speed eight said:
Hello Peter.
The distributor height "problem" can be negated by the use of a short body Mallory unit with a "crab" top cap.
This reduces a stock HEI unit by some 3".
Exhaust manifolds are also a breeze to sort out. Use the Hedman "super hugger headers" Now about £140.00 a pair, no stupid pricing there.
To keep the install at a low height then you can use a dual plain inlet manifold and a carb topped off by a "Low-Rider" style air filter unit, Mr Gasket do a splendid one for the job.
At the moment due to fuel prices, and my upcoming trip to Spain at the end of this month,
I am running with a mildly tuned up F.A.S.T.( Fuel Air Spark Technology ) sequential EFI 383ci again. Producing a REAL 450Hp flywheel and almost as much torque.
Torque from 2000 rpm is 400Ft-lbs and holds that plus some more right up to 6100Rpm.
It goes on to pull hard right through to 6900Rpm.
With my 3.08 rear diff gear that is 130Mph in 3rd!

Even though I have very high diff gearing, because of the massive torque, the acceleration is still blisteringly fast.
The swap out back to a 383ci is because I am aiming for mid 20's to the gallon + for cruising.
After quite a few engine combinations I have decide to stay with this one.........I think.
The ultra power engines of 500Hp + are just too much.
The torque from these mildly tuned 383ci motors is so far in advance of the TVR motors ( even the very fine new breed of Speed Six motors ) as to be off the scale by comparison.

With the 383ci motor nothing will break and I now believe that this is the best "all-round" combination for me.
I have always said that I am building a GT car, not a race car.
Fuel pricing is a consideration to me. I do not want to think, blimey I can't afford to drive it without thinking about it.
And at 18/10 to the gallon, using the ultra power 383ci to 454ci motors, that is how I was thinking.

I hope that you continue to research your dream car and keep asking questions and let us know how it is coming on.

Regards.
Speed eight.
Richard, very helpful as always, some great information. Just looking at the engine, in its standard instalation it's a tight fit, especially to the rear. I have tried to attach an image of my old car's engine bay. Lots to think about.

Regards

Peter




SprintV8

261 posts

237 months

Saturday 12th March 2011
quotequote all
From the tester manual.
http://www.motuk.co.uk/manual/contents.htm

If this hasn't been cleared up yet.

Vehicles Fitted with a different engine

Test according to which is older, engine or vehicle.
e.g. A 1995 car fitted with a 1991 engine (of whatever make), test to 1991 standards for emission purposes.

Note: The onus is on the vehicle presenter
to prove engine age.

pebi

41 posts

174 months

Monday 14th March 2011
quotequote all
Speed eight said:

Go to www.SummitRacing.com and look up part number MLL-BP3834CTCI
This is a genuine 420hp & 450ftlbs motor ready to run!
Hi there,


I just want to use the opportunity to ask some questions:

What does one need for a Tvr engine swap additionally to the
engine you posted here, the 650 HP SBC or whatever engine?
Do they include starter, wiring etc?
What about the clutch?
What gearbox does one need? TKO600 reasonable?
Is the fuel system re-usable?
What engine management system is recommendable?
And how about the exhaust?

Thanks for help.
Regards
PeBi

tinker-27

835 posts

229 months

Tuesday 15th March 2011
quotequote all
why would you fit a sbc when you could buy a ls1 for sensible money these days ? the sbc is a great motor and been around for years ,very reliable and cheap BUT the last one i fitted snapped my engine lift I AM NOT KIDDING !! buy a second hand ls1 a tko 600 and job done . you can fit a carb type intake for looks if you want and move the coils then enjoy . if you fit valve springs,pushrods,and a decent cam it will rev to 7,000 all day long with good mpg. a good ls1 will give 400 @wheels with a std bottom end just heads and cam package i would be interested to se wha spec sbc will do that at the wheels and what cam you would need to get that power and what it does to the drive-ability ? i am talking real power here not sellers figures !! Drive a car with both engines before you decide and spend your money (i think i know the answer already). his is not a dig at speedeight by the way

Alexdaredevilz

5,697 posts

184 months

Tuesday 15th March 2011
quotequote all
What are the weight differences between the ls1 and a sbc both dressed up?

Thanks

Alex

tinker-27

835 posts

229 months

Tuesday 15th March 2011
quotequote all
i dont know never had them on scales,is not just the cast iron part also the intake on a ls is plastic not cast alloy and even the carb is heavy !!

FactBV

Original Poster:

358 posts

229 months

Friday 18th March 2011
quotequote all
SprintV8 said:
From the tester manual.
http://www.motuk.co.uk/manual/contents.htm

If this hasn't been cleared up yet.

Vehicles Fitted with a different engine

Test according to which is older, engine or vehicle.
e.g. A 1995 car fitted with a 1991 engine (of whatever make), test to 1991 standards for emission purposes.

Note: The onus is on the vehicle presenter
to prove engine age.
Perfect, thank you and the reference confirms Speed Eight's experience with his Tuscan. So I don't need to have a precat car / chassis to do away with the cats as long as the engine is pre 1st August 1992 and I have to prove it to the tester / DVLA.

FactBV

Original Poster:

358 posts

229 months

Friday 18th March 2011
quotequote all
tinker-27 said:
why would you fit a sbc when you could buy a ls1 for sensible money these days ? the sbc is a great motor and been around for years ,very reliable and cheap BUT the last one i fitted snapped my engine lift I AM NOT KIDDING !! buy a second hand ls1 a tko 600 and job done . you can fit a carb type intake for looks if you want and move the coils then enjoy . if you fit valve springs,pushrods,and a decent cam it will rev to 7,000 all day long with good mpg. a good ls1 will give 400 @wheels with a std bottom end just heads and cam package i would be interested to se wha spec sbc will do that at the wheels and what cam you would need to get that power and what it does to the drive-ability ? i am talking real power here not sellers figures !! Drive a car with both engines before you decide and spend your money (i think i know the answer already). his is not a dig at speedeight by the way
I can see advantages to both, the SBC came up because it is cheap, looks old school and is a pre-1992 engine so you could do away with the cats, FI etc, I think that the first LS was 1997. It would not be for the track so the weight was less of an issue and even with new dampers and a 500 chassis my previous Griff hardly inspired confidence in corners, one small pot hole when pressing on and it was a cheek gripper. On the road and in the real world I can go around corners quicker in my S class. For me it was the sound, look, direct steering, torque and straight line speed. I need to find out more about the engines and have a go in some cars as you suggest.

Speed eight

336 posts

227 months

Saturday 19th March 2011
quotequote all
Peter..........I am e-mailing you.

Regards.
Speed eight.

jellison

12,803 posts

282 months

Thursday 26th May 2011
quotequote all
"the last one (SBC) I fitted snapped my engine lift I AM NOT KIDDING". hehehe

Oh and nothing wrong with cats - easy to have a few sports cats fitted to a custom system, why worry about it just build in to any system!

fatjon

2,298 posts

218 months

Tuesday 21st June 2011
quotequote all
definitive answer:

"Vehicles Fitted with a differnt engine

Test according to which is older, engine or vehicle.
e.g. A 1995 car fitted with a 1991 engine (of whatever make), test to 1991 standards for emission purposes.

Note: The onus is on the vehicle presenter
to prove engine age."

lifted from MOT manual today

http://www.motuk.co.uk/manual_730.htm