Uprated Cam...
Posted By : Andy Todd, 06-Jun-2005, 03:46pm
Hi Ian,
If you're not looking for more acceleration then in my honest opinion you're best bet is the standard camshaft, if you fit a cam to gain extra power you will lose some of the tractabililty round town, it is always a trade off. You won't go far wrong with a Vittesse Mk2/GT6Mk2/GT6Mk3(early) cam, the one with the 25-65-65-25 timing. You will also need the correct needles for the carbs which are readily available from the usual sources.
Andy Todd ( Wirral AO )
If you're not looking for more acceleration then in my honest opinion you're best bet is the standard camshaft, if you fit a cam to gain extra power you will lose some of the tractabililty round town, it is always a trade off. You won't go far wrong with a Vittesse Mk2/GT6Mk2/GT6Mk3(early) cam, the one with the 25-65-65-25 timing. You will also need the correct needles for the carbs which are readily available from the usual sources.
Andy Todd ( Wirral AO )
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Uprated Cam...
Posted By : Andy Todd, 06-Jun-2005, 03:55pm
Hi Ian,
Forgot to mention that if you opted for an uprated camshaft, you would also need to look at improving your exhaust manifold and exhaust, improving the gas flow through the head and possibly larger carburettors. Without looking at these you will not get the full benefit of the uprated cam.
Andy Todd
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Uprated Cam...
Posted By : Ian Johnson, 08-Jun-2005, 11:36am
Having a TR5 cam fitted, apparently it's much better and at &163;40 for a decent second hand one I don't think I can complain. I'm probably going to get the exhaust/manifold and bigger SU (1.75) carbs fitted some time early next year when money is not so tight - new engines are expensive! Cheers for the advice though Andy. See you at the July Wirral meeting.
Ian.-
Uprated Cam...
Posted By : James Carruthers, 08-Jun-2005, 11:42am
To get a new one ground is only about &163;80 anyway... though that's grinding your current one.
Turn around is less than a week too - I got mine back from Kent yesterday - I swear that its actually more visibly peaky by a big margin! Roll on the engine build!
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Uprated Cam...
Posted By : Ian Johnson, 08-Jun-2005, 11:51am
Is that the TR5 cam you're talking about? Do you drive a GT6 or Spit 1500? Can't remember sorry! The one I'm having fitted is only just over a year old and in really good nick so I don't really see the point of having it re-machined. Just extra expense!-
Uprated Cam...
Posted By : James Carruthers, 08-Jun-2005, 12:03pm
Noooo nooon noooooo... sorry I should have said - I got it reground to a Moss Fast Road 89 profile - good for at least 800bhp with buckets of torque for that extra acceleration. At least 700bhp at 3,000rpm too... special flowed head... extra torque... did I mention torque...?
I drive neither a GT6 or a 1500 (though I did have one of those once) - but a soon to be spanking Spitfire Mk3 - currently having a new engine rebuilt to replace the 20bhp special low compression IV unit currently in there...
Vroom vrrrooom!
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Uprated Cam...
Posted By : Colin Lindsay, 08-Jun-2005, 12:40pm
Ian - keep me informed on progress with this one; I bought a TR5 cam at Stoneleigh to replace the saloon cam I had had fitted to the earlier engine which I removed. At this time the engine's not yet on the road but I'd like to find out how yours performs with the new cam and anything you find which needs upgraded.
Colin-
Uprated Cam...
Posted By : Ian Johnson, 08-Jun-2005, 02:22pm
No problem Colin, all I've been at the moment is that it's a 125bhp cam and that, aside from the power, it's an all round better more 'useable' piece of kit, whatever that means... I'll keep you informed. The engine is being built this weekend, it should be fitted mid next week and I guess I'll have to run it in for a bit before I really know but I'll let you know as soon as I can tell anything!-
Uprated Cam...
Posted By : James Carruthers, 08-Jun-2005, 02:29pm
The G Thomas Tuning Manual reckons 155bhp for the 35-65 TR5/6 cam on a 2 litre... but I think that must be on PI or Webers.
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Uprated Cam...
Posted By : Ian Johnson, 08-Jun-2005, 02:45pm
Hmmm... cool... yum! 155 brake, I've only got 107ish at the moment I think... I'll have to sort that out, I've got plans boys and girls, soon I shall have the fastest GT6 in the world!! MU-HA HA HA HA HA HA HA HA!!! And... relax. Yeah, anyway, I fancy 200 or near enough like NiG said is possible, is that stupid? Because one way or another I'll find a way to get it from a 2litre. 2.5 is out of my league because nobody will insure me at my age (23). Once I get something in my head I usually end up doing it and damn the cost, usually to MY cost!-
Uprated Cam...
Posted By : James Carruthers, 08-Jun-2005, 03:08pm
Don't get too excited - no doubt that is on PI or Webers... and heavily ported etc etc
You can't get near 200 without grenade tuning it and with a full race cam - which will be no use on the road!
2.5 is the way if you want easy power! Are you sure nobody will insure you? Tried Adrian Flux?
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Uprated Cam...
Posted By : Ian Johnson, 08-Jun-2005, 03:37pm
Phoned them up a couple of times (Adrian Flux), their customer service was abysmal and the bint I got on the phone was abrupt and rude - two different people two separate times. Decided I didn't want to be dealing with that sort of people if I had to make a claim. They wouldn't even give me a quote when I told them I wanted the quote for over a month away they wouldn't do it. Even when I said, well, do me one for two weeks from today they said "no, we know you don't want it for then really so we won't do it". Almost as if they don't want my business! I may try them again in January when my premium runs out.-
Uprated Cam...
Posted By : Michael Charlton, 08-Jun-2005, 04:45pm
Plop in a decked 2.5. Get a number stamping set
Phil -
Uprated Cam...
Posted By : Andy Todd, 09-Jun-2005, 04:10am
Hi Ian,
I had a TR5 cam in my 2litre engine, tickover was lumpy and had to use full rev range to get the full performance out of the engine. I was running 1.75 inch strombergs and could not get the needles spot on. It will probably be easier to get an SU needle more suitable for that cam though. What I would recommend is a rolling road session as soon as the engine is run in to ensure that the fuel mixture is correct under all driving conditions, without this you might risk wrecking the engine. I now have a 2.5 with a higher lift version of the Vittesse Mk2 cam, ported and polished head and 1.75 SU's. 125bhp on the rolling road, 132lb/ft of torque, accelerates really well and very docile round town.
Andy Todd ( Wirral AO )
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Uprated Cam...
Posted By : Ian Johnson, 09-Jun-2005, 09:56am
So you think I might have issues with that cam then? I've got older GT6/Vitesse Stromberg CD150s and they have to be fitted to this new 2litre I'm having built as insurance on a 2.5 is a problem. I don't know if you know Max at Totally Triumph but would you think he'd have thought about all this before fitting the TR5 cam or would he just go ahead and do it without adjusting the needles? I know he doesn't have a rolling road or use one as far as I know. In a year of almost constant problems with my car I've never had a single problem with Max, he's always managed to fit me in, done great work and his prices are great. I just can't help but worry as I've had nothing but trouble with my car.
If I'm keeping these carbs (which I have to for a while until I can afford to have the manifold ported and 1.75" SUs like yours fitted) do you think I'll have to change the needles to suit? Is there anything else that will need changing?
I really do need it to be 'docile' as you say, around town as this is predominantly where I use it, I just don't want to suffer on torque or acceleration.
My problem is that, despite having a love for cars and old cars and Triumphs in particular, I'm not specifically mechanically minded and don't really have the time or experience to start getting up close and personal with my car's inner workings - I'm not in a position to be able to say, "ah, this needs doing" or "oh that's the problem, I'll do that myself". At the moment, I have to rely on other peoples' judgement and I feel at a bit of a loose end!-
Uprated Cam...
Posted By : Adrian Lee, 09-Jun-2005, 10:41am
Ian ,my vitesse had a standard MK1 engine in it,which was fine,however i got offered a rather cheap 2.5S engine which was too tempting to refuse.However,in standard form i found the mk1 to have ample torque and power,i suspect the mk2's are better due to the superior head,unless you want to race it or rally it,then is the standard version not adequate?
The su v stromberg will go on forever,but i put HS6's on the mk1 and they did improve it.
I've been to Max's a couple of times to buy bits off him,so i don't know what his work is like though he does seem a decent bloke.But, is there not a race prepped TR5 there and a modded GT6?I'm sure he used to race these ,so it may be as well to ask Max what he thinks about your requirements.
PS.........the fairly standard 2.5s i've squeezed in mine certainly brings a smile to my face.Sod the insurance cost you know it makes sense,&163;20 increase a year for me with Footman,worth every penny of it. -
Uprated Cam...
Posted By : James Carruthers, 09-Jun-2005, 10:42am
I friend of mine has a TR5 cam in his 2l GT6 - and it doesnt have any problems - goes pretty quick too!
He's on 1.75in SUs and his head had been mildly ported (I think)
As for driving the whole rev range to get the best out of the cam - you have to do that with any uprated cam. The basic cams Triumph designed for their stock engines were designed to give an all round economy/torque/bhp package to suit everyone without thrashing your motor. You can't put in an uprated cam without suffering on at least one of those.
The best cam seems to be the GT6 Mk2 one (25/65) - as that model seems to give out the best power figures - on paper at least.
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Uprated Cam...
Posted By : James Carruthers, 09-Jun-2005, 10:44am
Oh yeah - if you put in an uprated cam or mess with anything - a rolling road session has to be the way to go to sort out your car. You could have all manner of problems until you get the needles right - just fitting standard needles and adjusting the mixture wont work.
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Uprated Cam...
Posted By : Andy Todd, 09-Jun-2005, 11:52am
Hi Ian,
I wouldn't say I had issues with the TR5 cam, I just feel that it may be the wrong choice after reading your initial post stating what you wanted from this engine, but that is only my own opinion. I've never been to Max to get work done, but I don't doubt the quality of his work or advice, if there was a problem I'm sure we would of heard about it on this message board. If you do have the TR5 cam fitted, and you are running on 150CD Strombergs, then the rolling road session is a must. There is a limited choice of needles available for these carbs, so your needles will probably have to be modified to suit. In my experience standard needles will give you the correct fuel mixture at tickover, but no where else. As the revs increase the effects of Camshaft duration and valve overlap come into play, and as the airflow into the engine increases the mixture will get weaker and weaker. I had an air/fuel ratio meter connected to my GT6 and saw this happening.
As already suggested in a earlier post, it would be worthwhile speaking to Max, just so you are happy that you get a choice of cam suitable for your requirements, and some reassurance from Max that he can get the fuel mixture right.
Andy Todd
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Uprated Cam...
Posted By : Craig Gingell, 09-Jun-2005, 11:14am
I guess you're referring to Tim Bancroft's Mk2 GT6 -
http://www.tssc.org.uk/profile.asp?profile=83/0606...
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Uprated Cam...
Posted By : Robert Bell, 09-Jun-2005, 11:27am
James - any particular recommendations for rolling roads that are familiar with our cars?-
Uprated Cam...
Posted By : James Carruthers, 09-Jun-2005, 02:17pm
They only really need to be familair with your carbs.
Best to ask the racing boys this question!
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Uprated Cam...
Posted By : Ian Johnson, 09-Jun-2005, 02:28pm
Right, I've just spoken to my mechanic guy Max, he's said that the TR5 cam is fantastic BUT I'll find real trouble in finding the right needles for the Stromberg CD150s I've got just like Andy said - I did believe you Andy, just wanted a second opinion before shelling out my hard-earned cash!
I've decided to opt for the SU HS6 carbs instead with a ported manifold. This should make a decent difference in performance AND finding needles to suit is much easier. I know it's going to cost me extra (quite a bit) but it seems to be worth it. I kind of begrudge it as I've just (about a month ago) had a set of Mk2 Stromberg CD150 (non-emission control) carbs fully rebuilt. This was before I knew I needed a new engine though!
If any of you want (or know someone who wants) a pair of Stromberg CD150 (non emission controlled) carbs for the earlier GT6, very recently rebuilt to a very high standard I'll be selling them in about a week, I've been told they're worth &163;150 but I'll let them go for no less than &163;100 (literally no less, that would be giving them away!). Contact me if you're interested. I've also got a pair (once again fully rebuilt only three months ago - receipts from Totally Triumph available) of original Stromberg 1.5" (emission controlled) carbs for the Mark 3 GT6. These I'll let go for &163;70 if anyone's interested. You can contact me through private messaging me.
God this car will be the death of my bank balance... oh, hang on, what bank balance?!!
Thanks for everyone's advice on this subject.
Cheers!
Ian.-
Uprated Cam...
Posted By : James Carruthers, 09-Jun-2005, 02:32pm
Ian - you will have trouble finding original spec Stromberg needles because there arent as many as SUs - but if you go to a rolling road that know what they're doing, they'll be able to modifiy the needles to suit the engine exactly. It may be cheaper and practically the same outcome! Ideally you'll still want the SU needles to be modded anyway!
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Uprated Cam...
Posted By : Nigel Gibbins, 09-Jun-2005, 03:07pm
Ian, Have you considered profiling your needles yourself?
This will only take up some of your time and cost you nothing but the costs of some fine grit wet and dry paper.
You will need to find out the correct diameter for the needle at each 'step' then you can put the needle into a drill bit (fixed firmly to a bench) and use the drill as a lathe to file/grind the needle down to be richer. It will take a while to do, but will only cost you a few &163; for the wet/dry paper and maybe a book on needle profiling.
An emmsions tester (Gunsons?) would be useful but is not essential.
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Uprated Cam...
Posted By : James Carruthers, 09-Jun-2005, 03:20pm
The book "How to build and power tune SU carbs" has a very good explanation on how to reprofile needles - though of course its for SUs... the technique must be the same though...
http://www.veloce.co.uk/shop/products/productDetai...
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Uprated Cam...
Posted By : Adrian Lee, 09-Jun-2005, 03:56pm
Ill' vouch for this book,very good and it gives you the confidence to have a go............first time with some knackered HS2's in my case,in case it all went horribly wrong...............smiley face -
Uprated Cam...
Posted By : Nigel Gibbins, 09-Jun-2005, 07:02pm
Yep... that's the book I have too.... I recommend it!
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Uprated Cam...
Posted By : Chris Taylor, 09-Jun-2005, 01:44pm
Just a word of warning about insurance. You say you cannot afford (or get quoted even) for a 2.5 litre engine. Any quotes for a 2 litre engine will be on the (insurer's) assumption that your 2litre engine is in standard tune. Bigger carbs, uprated cams, even sports exhaust systems should be declared to the insurance company. It MIGHT make no difference to the premium, but it could more easily be used as an excuse not to pay out on a claim if it's found out later that the car is non-standard.
While a TR5 cam IS a "wilder" profile than the Mk2/Mk3 GT6 cam, not all TR6 cams are the same. Although there MIGHT be a difference in valve lift, I'm pretty sure the timing of the 125bhp TR6 cam is the same (25/65/65/25) as the GT6 one and the 2.5PI saloon, whereas the 150bhp cam is the same as the TR5 (35/65/65/35).
Triumph felt the need to use fuel injection rather than carbs to make the TR5 spec cam docile in traffic, and the TR6 was detuned because of reported idling issues with the earlier cam so you MAY lose some of the tractability in fitting that cam to the 2litre. However the proof of the pudding is in the eating etc, and it may well be that someone else has found the ideal spec of carbs, manifold, head or port mods and exhaust system to get the whole rev range improvement you seek while using the 35/65 cam or similar "fast road" modified profile.
It has to be said though that if I understand what it is you really want, the 2.5 litre is the easiest way of getting more urge without being in any way temperamental in traffic. As the americans say, there's no substitute for cubic inches (ie a bigger engine is always better). Just be aware of course that a bigger engine places more strain on the transmission, but I'll leave you to a completely different messageboard thread about uprating standard gearboxes or sqeazing in a saloon/TR/Dolly Sprint box!!!-
Uprated Cam...
Posted By : Mark Field, 09-Jun-2005, 07:55pm
ther are also other ways of tuning strombergs you can also use the heavier rings on the tops of the dampers as used on the herald 1360also there is a stonger spring then if you need to go even richer through the rev range tere is also a heavier damper from the early vittesse mk1 2ltr you must always remember to change every thing in pairs i hope im not teaching granny to suck eggs but this is how we tune strombergs running 120 to 150 horseon 2ltr engines hope this is of some help regards mark
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