TJ101 Posted March 16, 2011 Share Posted March 16, 2011 Guys, Whats the difference between a serpentine belt V8, and the original V drive belt engine Need to swap out the V8 engine already fitted, (twin alternators, Megasquirt etc) that's on Vee belts, with a 3.9 V8 with serpentine belts out of a Disco,, Job needs to be done like yesterday, so can/is it best to try and fit the Vee belt set up etc, rather than bugger about, and try getting the twin alternators etc to fit the later engine?? Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted March 16, 2011 Share Posted March 16, 2011 Tim The basic differences are : V Belt Small Oil pump driven off Dizzy Multiple belts - ie 1 x PAS and 1 x Waterpump and !x etc etc V Belts can squeal and give probs if belts get worn / loose Crankshaft is shorter Serp IMVHO A far superior Engine Longer crank gives CVrank driven pump 1 x Ferkin HUGE Belt - drives everything and never squeals Other minor changes prob cross bolted block = stronger bottom end I think engine mounts can vary, just swap them around - flywheel / clutch / manifolds etc all the same SO, YES you can fit a V front end to a Serp engine (spacer for end of crank required), but its a HUGE Downgrade IMHO. You can't really fit a Serp front end to a V Belt engine - as crank is too short, it can be done but is a bodge most of the time and done proffesionaly - prohibitive For Megasquirting the 3.9 Serp is a PITFA re the Coil pack mountings, as there is not much space, but Trigger wheel is the same, VR Sensor Bracket is not, VR Sensor is,PWM system is Coil packs are but mountuing as mentioned EDIS etc etrc all the same. Done the work on these if you wnat any bits, saves even more faffing about Best go Serp complete and get the bits needed, HTH Nige Quote Link to comment Share on other sites More sharing options...
ThreeSheds Posted March 16, 2011 Share Posted March 16, 2011 Wot HFH said. Another vote for serp - A belt change on serp is literally seconds with one spanner... Imagine doing a belt change on a v-belt ! If you need a 2nd alt, then you can use the A/C pump location to mount it. as mentioned, VR sensor bracket is different, but not a problem. Coil packs ok too if you make some space by removing the dizzy and blocking the hole with a RRC alloy style (blind) wheelnut with an the original o-ring over it, and the original clamp holding it. hope this helps Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted March 16, 2011 Share Posted March 16, 2011 I'd try fitting the twin alternators to the later engine, there's normally an aircon pump on the LH side of the engine, which with some bracketry jiggerypokery I am sure could be replaced with an identical alternator to feed your amps habit... The later serp alternators are higher ampage anywyas (100 or 120A) so you may find you don't need two.... Fitting the coil packs -I found making a bracket that is held in place with the vacuum take-offs on the RH side of the plenum to be a good compromise, alternatively you can always mount them on the bulkhead -hardly different to having them mounted right on the front of the engine. One thing I would do, is swap the trumpet base and plenum from the older V8, I think... they have 3 vacuum outlets rather than just one/two on the later ones (I may be getting confused with the P38 4.0 here...), and also the idle valve on the back of the plenum..... worth checking anyhow. Quote Link to comment Share on other sites More sharing options...
knacker Posted March 16, 2011 Share Posted March 16, 2011 Give Gwyn Lewis a call about a twin alternator bracket, he's just had are challenge truck in to make a prototype bracket for the serp V8. Jon. Quote Link to comment Share on other sites More sharing options...
TJ101 Posted March 16, 2011 Author Share Posted March 16, 2011 Thanks all Have a bottom end problem with the current engine fitted, (recon the MS was over fueling, and filled the sump !!) and need to fit this other lump by Friday evening !!! So plan is/was to pull the current engine, and put in the 3.9 Serp engine, but used the original Megasquirt, alternators etc So issues are Coil pack mounts VR sensor brk 24V alternator mount (Winch battery) 24V alternator Serp pulley I think engine mounts can vary, just swap them around - flywheel / clutch / manifolds etc all the same For Megasquirting the 3.9 Serp is a PITFA re the Coil pack mountings, as there is not much space, but Trigger wheel is the same, VR Sensor Bracket is not, VR Sensor is,PWM system is Coil packs are but mountuing as mentioned EDIS etc etrc all the same. Done the work on these if you wnat any bits, saves even more faffing about HTH Nige Nige,, have you a VR sensor brk in stock ?? Wot HFH said. as mentioned, VR sensor bracket is different, but not a problem. Coil packs ok too if you make some space by removing the dizzy and blocking the hole with a RRC alloy style (blind) wheelnut with an the original o-ring over it, and the original clamp holding it. hope this helps So will not need the oil pump drive adapter in the dissy hole as fitted to the V belt engine,, I'd try fitting the twin alternators to the later engine, there's normally an aircon pump on the LH side of the engine, which with some bracketry jiggerypokery I am sure could be replaced with an identical alternator to feed your amps habit... The later serp alternators are higher ampage anywyas (100 or 120A) so you may find you don't need two.... One thing I would do, is swap the trumpet base and plenum from the older V8, I think... they have 3 vacuum outlets rather than just one/two on the later ones (I may be getting confused with the P38 4.0 here...), and also the idle valve on the back of the plenum..... worth checking anyhow. Hopefully, i can find a home for the V belt engine coil pack bracket ?? Give Gwyn Lewis a call about a twin alternator bracket, he's just had are challenge truck in to make a prototype bracket for the serp V8. Jon. Will give Gwyn a call Quote Link to comment Share on other sites More sharing options...
ThreeSheds Posted March 17, 2011 Share Posted March 17, 2011 So will not need the oil pump drive adapter in the dissy hole as fitted to the V belt engine,, No - the serp v8 has a much better oil pump arrangement with a direct drive, so all you need to do to free up the space is block the hole... You can peel the o-ring off the dizzy, slip it onto an RRC blind wheel nut and slip it in the hole with a bit of goo - then use the original clamp to hold it in - 2 minutes When I changed mine (1990 RRC) I put in a 96 Disco serp v8 and everything went straight in including main mountings - I did change the plenum and ram-stacks as mentioned earlier to get the extra vacuum take-ofs, although not necessary, just easier for me. Oh - one other thing - do the VR sensor bracket while the engine is on the bench if you can... Best of luck with the installation - you must be well on the way by now.. Roger Quote Link to comment Share on other sites More sharing options...
TJ101 Posted March 17, 2011 Author Share Posted March 17, 2011 Thanks Roger I would be, if i have not got some much other things on as well, Wife being in hospital, with a badly bust arm, after one of the horses kicked her, is not helping !!! even have carp weeks !!! But the trays engine is out, and the Disco one is half way there Nige,, will ring you later this morning, to get the bits i need send down as soon as !!! Have a think what i MAY need, and just send them,, You will remember the org Vee engine, was Paul W's lump (top hats, Cross bolt, 3.9 block, 4.0lt heads etc ) Ian did the MS etc Quote Link to comment Share on other sites More sharing options...
ThreeSheds Posted March 20, 2011 Share Posted March 20, 2011 TJ101 - hopefully all is sorted now and you had a great weekend! In case anyone else is looking - I thought I would post a photo of the wheelnut distributor replacement, and coil bracket on mine. I botched the mounting together from two Orion mounts which came with the coilpacks, and always intended to make something better one day, but so far I haven't got a round tuit The (visible) mounting bracket has a bracing strut at the rear. Quote Link to comment Share on other sites More sharing options...
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