Discussion
I have just purchased a 450SE with solid lifters and a 404 cam (carried out by previous owner - I don't even know what it means).
To say it has a lumpy idle would be a bit of an understatement - it barely ticks over below 1500. Without touching the throttle it rocks around between 500 - 1000 when warm - when cold it needs a foot resting on the pedal.
When driving, if below 3000 it sounds like a misfire, in fact it is very difficult to drive it at a steady constant speed as all it wants to do is take off. The slightest touch on the throttle causes it to start to accelerate so to drive at 35mph it is either a fair few revs in 2nd or jerky progress in 3rd.
Under acceleration it goes well (ok it goes VERY well) but I am not sure I can live with it as it would be nice to be able to enjoy driving it in a mode other than full on bonkers.
Advice sought, please.
Does it sound as if the cam is the source of this frivolity or should I start checking a few other things ?
If it is the cam does anyone have experience of the same set up and can you get it to be driveable ?
If I have to change the cam what are the likely costs and the best options (I know - plenty of threads before but most are in relation to 400's)?
To say it has a lumpy idle would be a bit of an understatement - it barely ticks over below 1500. Without touching the throttle it rocks around between 500 - 1000 when warm - when cold it needs a foot resting on the pedal.
When driving, if below 3000 it sounds like a misfire, in fact it is very difficult to drive it at a steady constant speed as all it wants to do is take off. The slightest touch on the throttle causes it to start to accelerate so to drive at 35mph it is either a fair few revs in 2nd or jerky progress in 3rd.
Under acceleration it goes well (ok it goes VERY well) but I am not sure I can live with it as it would be nice to be able to enjoy driving it in a mode other than full on bonkers.
Advice sought, please.
Does it sound as if the cam is the source of this frivolity or should I start checking a few other things ?
If it is the cam does anyone have experience of the same set up and can you get it to be driveable ?
If I have to change the cam what are the likely costs and the best options (I know - plenty of threads before but most are in relation to 400's)?
Chunder - I've just had my engine changed to this cam - with solid lifters (allows higher revs than hydraulic).
My idle is not too bad - ticks over at 950 ~ 1000 revs.
My driving impressions : yes it does not like a constant speed and really likes to be driven - slightly annoying but that is the price you seem to have to pay for a higher performance cam.
Yes - it really want to take off ..
Some of this could be changed I suspect if you call Austec or Mark Adams - but much will remain.
Cost to change cam - £400 for cam and followers, fitting (£400) , ECU rechip (£325) Rolling Road (£400)
- just my guess from my recent experience.
Some of this will be cheaper if you DIY or accept less precision but best talk to an expert.
My idle is not too bad - ticks over at 950 ~ 1000 revs.
My driving impressions : yes it does not like a constant speed and really likes to be driven - slightly annoying but that is the price you seem to have to pay for a higher performance cam.
Yes - it really want to take off ..
Some of this could be changed I suspect if you call Austec or Mark Adams - but much will remain.
Cost to change cam - £400 for cam and followers, fitting (£400) , ECU rechip (£325) Rolling Road (£400)
- just my guess from my recent experience.
Some of this will be cheaper if you DIY or accept less precision but best talk to an expert.
Thanks chaps - not allowed to drive the car now until I get it registered and I need to change the speedo front etc before I can do that.
In the meantime I will check out the idle to see if I can get it steady and take it from there - maybe a few more drives and I could get more used to it.
Reverend - I was expecting a deep offbeat rumble but this spits and snarls at idle with the car visibly rocking - is yours like this ?
In the meantime I will check out the idle to see if I can get it steady and take it from there - maybe a few more drives and I could get more used to it.
Reverend - I was expecting a deep offbeat rumble but this spits and snarls at idle with the car visibly rocking - is yours like this ?
chunder said:
Thanks chaps - not allowed to drive the car now until I get it registered and I need to change the speedo front etc before I can do that.
In the meantime I will check out the idle to see if I can get it steady and take it from there - maybe a few more drives and I could get more used to it.
Reverend - I was expecting a deep offbeat rumble but this spits and snarls at idle with the car visibly rocking - is yours like this ?
No - it ticks over with no problems .. but it sounds very purposeful - bit like a top fuel dragster - where each cylinder is an explosion rather than a burn ... if you know what I mean.
Bear in mind that some TVR's don't tick over well due to other reasons like : steppa motor dirty / needs replacing etc..
rev-erend said:
bit like a top fuel dragster - where each cylinder is an explosion rather than a burn ... if you know what I mean.
Bear in mind that some TVR's don't tick over well due to other reasons like : steppa motor dirty / needs replacing etc..
Yes that's the sound.
Maybe all will be well then if I can get the idle sorted.
Not got a couple of plug leads crossed? 
Sounds to me like something other than the cam.
I'd recommed booking in for a Mark Adams session.
Once warm, my 404 cam idle is pretty smooth (about 1200rpm) but revs drop noticably when the headlights are on.
In traffic it's not at all bad and 4th is very usable in built up areas. Very little shunting.
FYI - the 404 a LOT smoother than the original H234 cam! Far more like a 'normal' car to drive.
I'd recommed booking in for a Mark Adams session.
Once warm, my 404 cam idle is pretty smooth (about 1200rpm) but revs drop noticably when the headlights are on.
In traffic it's not at all bad and 4th is very usable in built up areas. Very little shunting.
FYI - the 404 a LOT smoother than the original H234 cam! Far more like a 'normal' car to drive.
Nacnud said:
Sounds to me like something other than the cam.
I'd recommed booking in for a Mark Adams session.
Once warm, my 404 cam idle is pretty smooth (about 1200rpm) but revs drop noticably when the headlights are on.
In traffic it's not at all bad and 4th is very usable in built up areas. Very little shunting.
FYI - the 404 a LOT smoother than the original H234 cam! Far more like a 'normal' car to drive.
Glad that I did not get a 234 or wilder then
My 450SE is on std cam. Yep it rocks from side to side when on idle, usually idles at 1200rpm + or - 200 depending on what day of the week it is !! It does not like going at less than 1500 RPM in 3rd gear or above, pulls like a train between 1500 and 3000 RPM and then goes into warp drive.
Enjoy your 450, it must be the only one in Australia !!??
Regards
Nige'
Enjoy your 450, it must be the only one in Australia !!??
Regards
Nige'
Nige', that's pretty much what it is like - perhaps there isn't much wrong with it and I am just not used to a BBW.
Yes it is the only 450 in Aus, couple of 390's here in WA (out of about 10 TVR's in total in a state with 2 million people that's 4 times the size of the UK !) but I am not aware even of any 400's in the rest of Aus either. Maybe because import laws only allow in vehicles 15 years old or ones that you have owned and used overseas for 12 months.
Batteries out being charged at the moment and just plugged the vacuum hose back onto the fuel pressure regulator where it had fallen off - don't suppose this would have affectd the idle but once I pick up the altered speedo and put the dash back I will try and get that sorted.
Also need to somehow tie the battery down as otherwise it will fail the registration inspection - I removed a self tapper and an inch long bit of rotted strap that I assume was some kind of tie down -has anyone fitted a proper bolt down bar or some other kind of holder ?
Yes it is the only 450 in Aus, couple of 390's here in WA (out of about 10 TVR's in total in a state with 2 million people that's 4 times the size of the UK !) but I am not aware even of any 400's in the rest of Aus either. Maybe because import laws only allow in vehicles 15 years old or ones that you have owned and used overseas for 12 months.
Batteries out being charged at the moment and just plugged the vacuum hose back onto the fuel pressure regulator where it had fallen off - don't suppose this would have affectd the idle but once I pick up the altered speedo and put the dash back I will try and get that sorted.
Also need to somehow tie the battery down as otherwise it will fail the registration inspection - I removed a self tapper and an inch long bit of rotted strap that I assume was some kind of tie down -has anyone fitted a proper bolt down bar or some other kind of holder ?
Bob,
My battery is held in place by a rubberised strap, that is beginning to perish, one side bolted to the bulkhead and the other smaller strap bolted to inner wing, both straps fixed together by basic buckle. My old 280i battery was held in place by a metal tie bar, but was located on the opposite side of the car to the 450. Locating bars had been positioned in holes drilled into fibreglass wings. Hope this helps.
My 450 does not like to be stood still for more than 2 weeks otherwise it seems ages before she "wakes up" and starts ruinning as she should do. Also my car idles much better since I changed my battery and the headlamps now pop up at the same time !!
Regards
Nige'
My battery is held in place by a rubberised strap, that is beginning to perish, one side bolted to the bulkhead and the other smaller strap bolted to inner wing, both straps fixed together by basic buckle. My old 280i battery was held in place by a metal tie bar, but was located on the opposite side of the car to the 450. Locating bars had been positioned in holes drilled into fibreglass wings. Hope this helps.
My 450 does not like to be stood still for more than 2 weeks otherwise it seems ages before she "wakes up" and starts ruinning as she should do. Also my car idles much better since I changed my battery and the headlamps now pop up at the same time !!
Regards
Nige'
Made a new battery strap, fitted the immobiliser, got the fuel filler top cut off and a new restricted top glued in (restricts it to unleaded nozzles only), set the idle up correctly as per various other threads, free'd up the sticking AFM flap that was causing the low revs jitters and got it inspected in order to register it.
Failed on leaking valley gasket (I forgot to wipe the oil from the bell housing first - gasket being replaced now anyway) and the bonnet vents !
Jobsworth examiner reckons the top one is dangerous as it points at the windscreen and any oil / water blow out could come through the vent and block vision.
Now been advised to take it to the examiner who passed a 390 recently with exactly the same bonnet vents so hopefully will be on the road soon. The couple of trips I did manage while under a permit showed that it now idles fine at 1000, is smooth and pulls strongly under 3000 whilst above is pretty furious.
Thanks for the help and suggestions - will keep posting on progress and hopefully can attend the British Car Day in it which is coming up in two weeks.
Failed on leaking valley gasket (I forgot to wipe the oil from the bell housing first - gasket being replaced now anyway) and the bonnet vents !
Jobsworth examiner reckons the top one is dangerous as it points at the windscreen and any oil / water blow out could come through the vent and block vision.
Now been advised to take it to the examiner who passed a 390 recently with exactly the same bonnet vents so hopefully will be on the road soon. The couple of trips I did manage while under a permit showed that it now idles fine at 1000, is smooth and pulls strongly under 3000 whilst above is pretty furious.
Thanks for the help and suggestions - will keep posting on progress and hopefully can attend the British Car Day in it which is coming up in two weeks.
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