Input needed... induction options on monster 4.3
Discussion
Soooo... I finally have this great humping' RV8 lump of alloy sticking in the engine bay of my Chimaera (except front pulley/balancer and thus ignition and exhaust Y-piece still not back in either) and i've been told to run it in before having a remap or maybe an Omex doing its managing bit (would need to be out of my current financial canyon for that to happen, though). Before that, I will need to have to sort out the induction side of things as that all is 'absolutely standard, old boy' except a silicone elbow for the AMM-throttle hose that I'd managed to blag myself before the engine got out.
For those that may have missed the 'The Engine' thread over at TVR general (that'll be all of you as there weren't any replies
) here's a short recap of the spec with pics:
New crank with the bigger journal bearings; new con rods to suit w/ARP bolts (not pictured)
ACL bearings
Forged pistons w w/valve pockets, 11.6:1 compression ratio (I have the option of exclusively running 98+ RON fuel here)
O-ringed heads, extensively reshaped ports, the Big Valves, new valve guides etc.
Piper camshaft, bespoke spec for this engine (I'm told it has actually less overlap than the -very knackered- TVR214 that came out, but assumedly rather more lift); new Duplex vernier timing gear which should be more reliable than the OE items.
Lightened flywheel
Rocker gear is all new and uprated, but still hydraulic.
The object - as far as I understand it - was to create a smoother, more driveable engine than the big 5.X kind of stuff, with the power spread out over a wide rpm band and a more 'revvy' character befitting a sports engine. Therefore the builder stuck with 77 mm stroke. Given all of the above, it should be able to give most 5 litres a run for their money I reckon, albeit without the big slug of midrange torque (still running a Rover 'box, too!).
Anyway...
What can be done at a low budget to make the best out of this beastie? Tim at ACT seems to reckon a set of carbon superflare trumpets (just the normal 38 mm ones) would give the biggest bang for buck, then it comes to doing the rest of the intake upstream of the AMM (the air filter and the two pipes) and bigger throttle plates in the OE plenum being only good for 3 bhp. At a leter date I could put a twin throttle plenum on top of that, but honestly unless someone upgrades to bigger and better things with the twin throttle stuff becoming redundant, I don't see that happening for a while... TCS's intake kit for the RV* sounds nice, too (haven't been able to speak to Jools about it yet), but then I gather this may be more applicable to the Griff which has an inferior layout from the factory compared to the Chim.
The original idea was to put eight throttle bodies and aftermarket management on it, but as I'm not running a cam with really wild overlap I'd say I can still get away with having a plenum; apart from that I won't be able to upgrade the rest of the car (suspension, brakes, chassis? - it's the old pre-'500' one...) to the same level. I'm merely looking for a good touring/ (very) occasional track spec; a bit like what Marcos was trying to achieve on their last models...
Thanks in advance for any ideas (and looking forward to a good discussion!
).
For those that may have missed the 'The Engine' thread over at TVR general (that'll be all of you as there weren't any replies
) here's a short recap of the spec with pics:New crank with the bigger journal bearings; new con rods to suit w/ARP bolts (not pictured)
ACL bearings
Forged pistons w w/valve pockets, 11.6:1 compression ratio (I have the option of exclusively running 98+ RON fuel here)
O-ringed heads, extensively reshaped ports, the Big Valves, new valve guides etc.
Piper camshaft, bespoke spec for this engine (I'm told it has actually less overlap than the -very knackered- TVR214 that came out, but assumedly rather more lift); new Duplex vernier timing gear which should be more reliable than the OE items.
Lightened flywheel
Rocker gear is all new and uprated, but still hydraulic.
The object - as far as I understand it - was to create a smoother, more driveable engine than the big 5.X kind of stuff, with the power spread out over a wide rpm band and a more 'revvy' character befitting a sports engine. Therefore the builder stuck with 77 mm stroke. Given all of the above, it should be able to give most 5 litres a run for their money I reckon, albeit without the big slug of midrange torque (still running a Rover 'box, too!
).Anyway...
What can be done at a low budget to make the best out of this beastie? Tim at ACT seems to reckon a set of carbon superflare trumpets (just the normal 38 mm ones) would give the biggest bang for buck, then it comes to doing the rest of the intake upstream of the AMM (the air filter and the two pipes) and bigger throttle plates in the OE plenum being only good for 3 bhp. At a leter date I could put a twin throttle plenum on top of that, but honestly unless someone upgrades to bigger and better things with the twin throttle stuff becoming redundant, I don't see that happening for a while... TCS's intake kit for the RV* sounds nice, too (haven't been able to speak to Jools about it yet), but then I gather this may be more applicable to the Griff which has an inferior layout from the factory compared to the Chim.
The original idea was to put eight throttle bodies and aftermarket management on it, but as I'm not running a cam with really wild overlap I'd say I can still get away with having a plenum; apart from that I won't be able to upgrade the rest of the car (suspension, brakes, chassis? - it's the old pre-'500' one...) to the same level. I'm merely looking for a good touring/ (very) occasional track spec; a bit like what Marcos was trying to achieve on their last models...
Thanks in advance for any ideas (and looking forward to a good discussion!
). Edited by 900T-R on Thursday 20th December 15:23
I think most people would do it ahead of your heatshield on the AFM 
....
On RR very positive, when everything is hot positive, you could argue on fast cruise with a lot of cooling air maybe not so much? Keeping charge cool has to be a plus, putting it in during re-assembly seems to be a no-brainer IMHO.
Trumpet base out to 45mm? then. You still want to make sure you match the inlets and exhaust ports as close as possible (prob the most gainful 'tweak' IMHO).
Remember a lot of the difference in genuine BV and just BV heads is probably all these other little 'matching/flowing' differences.
I think someone mentioned heat shield on the fuel delivery side as a positive a while ago.
If you want top end power I think you should consider just blending the base & forget trumpets ~ it always seems a lot less trouble to me.
Dave
....On RR very positive, when everything is hot positive, you could argue on fast cruise with a lot of cooling air maybe not so much? Keeping charge cool has to be a plus, putting it in during re-assembly seems to be a no-brainer IMHO.
Trumpet base out to 45mm? then. You still want to make sure you match the inlets and exhaust ports as close as possible (prob the most gainful 'tweak' IMHO).
Remember a lot of the difference in genuine BV and just BV heads is probably all these other little 'matching/flowing' differences
.I think someone mentioned heat shield on the fuel delivery side as a positive a while ago.
If you want top end power I think you should consider just blending the base & forget trumpets ~ it always seems a lot less trouble to me.
Dave
spend said:
I think most people would do it ahead of your heatshield on the AFM ....
Hey, unlike the insulator plate it cost me nowt! ....can you tell I am Dutch
spend said:
Remember a lot of the difference in genuine BV and just BV heads is probably all these other little 'matching/flowing' differences .
Given the (count'em) 397 hours allegedly spent on this engine (builder took it as a development project of sorts) I'd take some serious work having been done on this front as a given... .lwt said:
IMHO you are wasting the potential of this fine engine if you don't fit an aftermarket engine management system.
Well, at several points in time I did say to the engine builder - you do know what car this engine is going into, and that I haven't got any money really? the kicker is - apparently the crank sensor for an aftermarket ECU is already installed (not that I can find it anywhere in the pics I got)
Edited by 900T-R on Thursday 20th December 18:55
No need for the carbon jobs just fit 45mm ally ones instead, When I fitted a the 45mm intake on mine (a tuned 4 ltr) it made a big difference much more eager to rev and filled in a hole in the torque curve lower down.
I'd have said with all the mods and a big enough throttle you'll make in excess of 300 ponies
Matt
I'd have said with all the mods and a big enough throttle you'll make in excess of 300 ponies
Matt
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