Pre serpentine engines?

[Brithunter]

Have noticed several early cars with the vee belt equipped pre serpentine engines that have the flange bolted manifold joint to the Y piece and if I read correctly these do not have the pre cats like the later engines do!

So apart from having no pre cats is their any advantage to the pre serpentine engines?

Any disadvantages?

Am just trying to narrow the field in my searches slightly. Not that it seem to be working ....................................... as yet.

Edited by Brithunter on Sunday 8th January 23:41

[BeastMaster]

Just a suggestion.

When considering buying a Chimaera I bought a copy of the bible (note the use a non capital letter) by Steve Heath which is a great read for anyone interested in these great cars and invaluable if you want to buy one.

All the answers to your questions are to be found in this publication and more.

The Pre serp. engine was used until around the end of 1994, I think it became law for all production cars to be fitted with Cats at some time in 1993, although with TVR it is impossible to be certain as they built many with the parts that were available at the time of assembly.

Andy

[Brithunter]

Sadly the book is not available new at the moment so unless we can secure a good used copy we are out of luck.

[Paulprior]

Theres a couple going on ebay at the moment

[TV8]

I think all of the Chimaeras, bolted or clamped manfolds, were cat ones. The early cars had the Rover box. Good ratios for the TVR in my opinion. Not as strong as the T5 of the later cars but a good box if used with difflock oil.

[Brithunter]

Paulprior said:

Theres a couple going on ebay at the moment

Noticed and have them on my watch list. Also found somewhere that lists it but they do not say if they have any stock so will have to contact them directly the check.

[ukdj]

Brithunter said:

Sadly the book is not available new at the moment so unless we can secure a good used copy we are out of luck.

Still available direct from Steve Heath HERE

[Brithunter]

TV8 said:

I think all of the Chimaeras, bolted or clamped manfolds, were cat ones. The early cars had the Rover box. Good ratios for the TVR in my opinion. Not as strong as the T5 of the later cars but a good box if used with difflock oil.

Thank you for the information. A couple that have been looking over the photos in the ads of are early ones with the door release on the rear wing not the mirror. At least one with the engine bay photos has the manifolds like the Griffith with the ring or bolts around it at the "Y" join.

Edited by Brithunter on Sunday 8th January 08:33

[ianwayne]

ukdj said:

Still available direct from Steve Heath HERE

That's a good find. I've seen bidders getting carried away on ebay and paying more than that for a used copy.

[TV8]

Brithunter said:

Thank you for the information. A cuple that have been lookign over the photos in the ads of are early ones with the door release on the rear wing not the mirror. At least one with the engine bay photos has the manifolds like the Griffith with the ring or bolts around it at the Y join.

There are two things there. The type of connection between the y piece and the manifold headers. From memory, the precat Griffiths are probably bolted but have more pipe work to the exhaust ports whereas the cat Chimaera has stubbier looking manifolds.

[simonwedge]

The oil pressure relief valve on pre-serp engines can sometimes stick open resulting in complete loss of oil pressure - with obvious results. I know this because mine did exactly this.

The oil pressure relief valve, and indeed the whole oil pump was much improved on the serp engines. They are much more reliable and they produce better oil pressure.

When my engine was rebuilt I therefore had it converted to the full serp set-up.

[FoxTVR430]

I have a pre-serp 4.3 Chimaera made in August '93.
This has the following:
V-belt
Bolted manifolds to main down pipe
Pre-cats
Main cat
One main water expansion tank. Later versions had a separate expansion tank
...

Photo of the engine bay when I bought it

[Sardonicus]

The pre-Serp also comes with a tidier less cluttered engine wiring loom and a neater and more common sense heater coolant plumbing loop/route too

[carsy]

Dont let the pre serp oil pump put you off one. The relief valve can stick on any engine, pre serp or serp.

Ok the serp pump is probably a better arrangement but look at all the pre serp wedges. Rover will have produced thousands of these engines without issue.

[Sardonicus]

carsy said:

Dont let the pre serp oil pump put you off one. The relief valve can stick on any engine, pre serp or serp.

Ok the serp pump is probably a better arrangement but look at all the pre serp wedges. Rover will have produced thousands of these engines without issue.

Agree with this

[Brithunter]

simonwedge said:

The oil pressure relief valve on pre-serp engines can sometimes stick open resulting in complete loss of oil pressure - with obvious results. I know this because mine did exactly this.

The oil pressure relief valve, and indeed the whole oil pump was much improved on the serp engines. They are much more reliable and they produce better oil pressure.

When my engine was rebuilt I therefore had it converted to the full serp set-up.

Ahhh so the oil pump and pressure relief on the earleir pre derpentine engines can be upgraded ................................. nice to know.

[BeastMaster]

Brithunter said:

simonwedge said:

The oil pressure relief valve on pre-serp engines can sometimes stick open resulting in complete loss of oil pressure - with obvious results. I know this because mine did exactly this.

The oil pressure relief valve, and indeed the whole oil pump was much improved on the serp engines. They are much more reliable and they produce better oil pressure.

When my engine was rebuilt I therefore had it converted to the full serp set-up.

Ahhh so the oil pump and pressure relief on the earleir pre derpentine engines can be upgraded ................................. nice to know.

Anything can be upgraded, to do this the whole front casting will require changing, pulley wheels, water pump is different, power steering pump is different, the crank nose will require modification because the keyway is different so probably could be a couple of grand.
All the so called upgrades which happened during the production run were probably to do with availability and not as a fault elimination process.
IMHO these cars are pretty much bomb proof, whatever the spec. with the exception of perhaps 2 or 3 key items to look out for, after which you pays your money and makes your choice, and depending on budget will decide for you on age condition and spec.

Andy

[Brithunter]

Just over a year has gone since I asked these questions and thanks to the help found on these forums bought a 93 Chimaera 430 so yes a Pre-Serp one. It was purchased on condition after a pre purchase inspection done by Heath at X Works. Am now in the process of putting a spares and break down kit together for a European trip across to the Black Sea.

Now in his preparation service Heath fitted new ceramic leads so they should be go to go for a while.

Now for the rest so far have secured a new old stock ignition amp but still have:-

coil,

cap,

rotor arm,

alternator (Vee) belt

and fuses to get.

Is it worth getting a new spare 100A fuse holder?

[Classic Chim]

Brithunter said:

Just over a year has gone since I asked these questions and thanks to the help found on these forums bought a 93 Chimaera 430 so yes a Pre-Serp one. It was purchased on condition after a pre purchase inspection done by Heath at X Works. Am now in the process of putting a spares and break down kit together for a European trip across to the Black Sea.

Now in his preparation service Heath fitted new ceramic leads so they should be go to go for a while.

Now for the rest so far have secured a new old stock ignition amp but still have:-

coil,

cap,

rotor arm,

alternator (Vee) belt

and fuses to get.

Is it worth getting a new spare 100A fuse holder?

Probably, more for future use but a good idea to have one. Some early cars don’t have it I seem to think so do check where it’s located etc.

Dif and gearbox oil, have they changed in the last few years via service history?
Your long journey will test these components a little

[QBee]

If you are buying fuses, consider “glow when they blow” fuses. Not expensive, and you will know at a glance rather than a grovel in the footwell if any have blown. I changed all mine for about a tenner.

Stick that description in EBay search......