Camshaft ID

[andy thompson]

Hugh - forget the TH7 - it just won't work on a 2.5 -

[Hugh]

lagerzok wrote:

Hugh - forget the TH7 - it just won't work on a 2.5 -

Hi Andy but why do you say it will not work the guy selling it had it in his 2.5 and Kent make it for the TR6 engine  :-/

[Nick Jones]

Hmmm, just because they exist doesn't mean they are a good idea.

IMO the 2.5 is all about lazy torque low down, hopefully moving up to real mid-range punch.
Kent describe the TH7 as a "race" cam and  their own info gives a powerband of 3750 - 8000 rpm.  Realistic redline for a stock based 2.5 engine is 6000 rpm.  It will be lumpy as hell at the bottom end, you might tame it to an extent with electronics but getting a PI metering unit to work with it will be a horror.

There are also those who regard any Kent product for Triumph as an expensive way to fill your sump with swarf and knacker your oil pump...... I've had a TH3 in a Herald engine and that was still ok after 20k - bar a couple of lightly pitted followers.

Advantage of using Triumph/Triumph derived profiles such as 132 hp PI cam or TR5 cam is that the MU details are well known and work.  They will also deliver decent grunt low down and mid-range where you can enjoy it all the time.

If you want something that will "rev to Smiths" best to stick with 2L, but I still reckon you'd struggle to enjoy a TH7 on the road.

For info, friend has just built a TR6 engine with a Newman PH1 (very mild) and electronic management.  In between slaying gremlins we managed a short run up the road last night and it certainly does go....... idles like a clock at 700rpm too.

Nick

[andy thompson]

Hugh - nick has summed it up - 2.5 should pull well from 2000 to 6000 with lovely smooth torque - TH7 will be a nasty bag of nails under 3500-4000 especially with Lucas PI - if it starts to work by the time it comes on song its time to change up -its a race cam (sort of) for a revvy engine.

[Hugh]

So would this cam work with triple carbs instead of pi just a thought :-/

[Clive]

Hugh, I would follow thye advice given. I ran my 2.5 vitesse (on SU's) with all std cam etc and it was superb.
When I obtained a recon short TR6 engine, I put in the piper "warm" cam and although it probably went better at the very top end, it was never as pleasant to drive. That is the engine now in MikeyB's PI saloon, and doesn't appear to work well on PI either.

The above chappies have been there done it etc etc, my experience is tiny in comparison, but I would go for a factory spec cam. Do not be tempted, you will end up regretting it. Honest.
Besides, I expect the seller is wanting rid of it as he is fed up! Won't admit to it, but I reckon that is the reason.

[Hugh]

Okay TR5 cam it is then ;)

[Clive]

Very wise!

[CRAJ]

TRTOM2498 wrote:

Agree with Andy. I run a Newman cam with their steel followers.  No issues what so ever.

X7 track days, regular 6500rpm and 15k miles so far with no noises or cam issues.


Cheers

I can vouch for what Tom is saying about his TR6, breathtaking around the track!
A friend with us at Blyton ruined his 2001 MR2 VVTi trying to keep up with Tom in his TR, this friend is GOOD on the track but ended up over revving the lump by down changing to early trying to stay with the TR. It sounded like a diesel when he came back in the pits.
Love em or hate em those MR2s are a quick car, they shouldn't have a problem staying with a TR6!
A friend of mine also has the Newman TR5 cam and followers in his mk1 pi estate....lots of power and grunt and works very well with Lucas injection.

Colin