Preserp Engine
Discussion
The distinguishing charcteristic is the 'serpentine' route followed by the fanbelt - it goes round more pulleys.
1991-2: Pre-serpentine: 4.0, 4.3, 4.5, 240-280bhp
1993-2002: Serpentine: 5.0, 340-320bhp
(all bhp figures token only)
IIRC the drop from 340 to 320 bhp was done to aid smoother running in about 1997, and achieved in the ECU rather than cam. Nowt to do with serp/preserp.
1991-2: Pre-serpentine: 4.0, 4.3, 4.5, 240-280bhp
1993-2002: Serpentine: 5.0, 340-320bhp
(all bhp figures token only)
IIRC the drop from 340 to 320 bhp was done to aid smoother running in about 1997, and achieved in the ECU rather than cam. Nowt to do with serp/preserp.
Hmmmm, some of the early 500s were pre-serp weren't they? There's loads in the archives though, probably in answer to me asking the same questions 
pre-serps have a few different belts to run the ancillaries where as the serpentines run all the ancillaries off the one long and bendy (tech term) belt.
They also have different oil pumps which I believe are supposed to be better but don't trust me wait for some one who really knows what they're talking about to answer properly!
Cheers,
Rob
pre-serps have a few different belts to run the ancillaries where as the serpentines run all the ancillaries off the one long and bendy (tech term) belt.
They also have different oil pumps which I believe are supposed to be better but don't trust me wait for some one who really knows what they're talking about to answer properly!
Cheers,
Rob
Quinny said:
The pre serp is the original and best .
The belt on my pre serp runs the water pump and alternator.
The belt on the serps run the alternator, water pump, power steering pump aircon, cd player and kitchen sink.
If you feel you need all these ancillaries to make life easier go for a serpentine.
Seconded, but you forgot to add the cigarette lighter as well
...zz
5.0l engines were available in pre-serp and serp as rob rightly says.the serp engine 'evolved' as an improvement,mainly with the oil pump,all serp engines therefore have the better 'constant volume' pump,as opposed to the ordinary oil pump on a pre serp.it is due to this,that they are regarded as the better and more reliable of the two versions-although how much justification there is for this tag is debatable as ive never heard the pre-serp referred to as less reliable.the hc(340bhp/350ftlb) version of the 5.0l engine was available with serp engines from its inception until tvr stopped using them it seems,although i imagine it was only produced on request after about 97/98 as they become hard to find after that.
>> Edited by mongoose on Saturday 28th February 09:30
>> Edited by mongoose on Saturday 28th February 09:30
Pre-Serp Aux drive belt looks like this. Some early 500 were fitted with pre-serp engines (like mine). The pre-serps were supposed to be tunned to deliver a bit more power than a serpentine but they are rough below 2000 revs and tend to jolt and shunt the transmission through town. I think the oil pump is also different on the serpentine engines which are less prone to priming problems.
...
serp is a front end make over for the rv8. better water and oil distribution but the block etc is basically the same.
earlier cars with pre-serps are rougher but tougher giving closer to the (ha ha) 340bhp supposedly on offer.
serp's SHOULD therefore be more driveable but not so pockey, but since pre-serps are older and have more miles this avantage will noe be lost.
unles...see profile
serp is a front end make over for the rv8. better water and oil distribution but the block etc is basically the same.
earlier cars with pre-serps are rougher but tougher giving closer to the (ha ha) 340bhp supposedly on offer.
serp's SHOULD therefore be more driveable but not so pockey, but since pre-serps are older and have more miles this avantage will noe be lost.
unles...see profile
royb said:
can anyone tell me what a 5ltr pre serpentine engine is and is it good, bad or?
It is my belief that the pre-serp is 340BHP and the serp is 320BHP. The belt configurations are as already has been said.
(No one really knows what HC means and rather than clog this thread up with HC fisty cuffs do a search for an existing thread, there must be a few on this topic!).
The earliest serpentine'd griff was made in the 2nd half of 1994. It is likely that all '95 onwards cars are Serps (Although I think the recent 4.6 in the PH calssifieds has thrown us all!).
The other thing to consider is what came with the serp.
Most serps (if not all) came with the more robust Borg Warner T5 gearbox as a replacement of the rover one.
They also came with bigger brakes and some chassis reinforcement and improved suspension (although this may be all 500's. It isnt 100% clear on Steve Heaths website).
All this information and more can be found in shpub's website.
www.tvrbooks.co.uk/
Griff buying guide
www.t-v-r-services.co.uk/tvrbooks/GriffGuide.pdf
BTW: I dont own a griff but I do have an anorak!
>> Edited by DustyC on Saturday 28th February 19:12
The serp engine's oil pump is no better, some think it's worse as it is integrated into the engine's front cover and therefore more of a pain to replace/service. Landrover did the re-design to the engine purely to make a more compact engine package and to make the engine cheaper to produce.
dusty,your beleif that all serps are 320bhp is,im afraid,wrong.tvr continued to produce the hc spec 500 well into serp production until 97/98ish as i said earlier.then they mostly went to 320 bhp but the 340bhp hc version was always available on request it seems.as si hunter says,all 500 engines were hc,but this is only true when refering to the high lift cam part of the spec.the hc spec 500's had a different ecu and thats where the power difference comes from.this is also why they are distinguishable by being lumpy at the bottom end and more difficult to drive around town than a std 500.an easy and inexpensive solution to this lumpiness is to remove the pre-cats,i can well recommend it
I'd have to agree with jigs on the gearbox point - most of these cars are getting on a bit now, and if my gearbox did go bang, I'd rather be trawling round the old Rover SD1s in the scrappy than pricing up a T5 from somewhere 
On the oil pump thing, as far as I know, the serp oil pump gives a better pressure at low engine speeds ie idle than the older 1950's design, and supposedly doesn't cause pressure/priming problems after draining the oil out. But then again, if it won't prime, the preserp pump is easy to fill with vaseline, whereas the newer pump is supposedly more difficult to pack
six of one, half a dozen etc
On the oil pump thing, as far as I know, the serp oil pump gives a better pressure at low engine speeds ie idle than the older 1950's design, and supposedly doesn't cause pressure/priming problems after draining the oil out. But then again, if it won't prime, the preserp pump is easy to fill with vaseline, whereas the newer pump is supposedly more difficult to pack
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