2500S Engine - Confused

[Bradley1500]

Been looking up the specs of the 2500S Engine and found some contradicting information.

On the CT site it states the S engine produces 99bhp.

[Sorry, link no longer available]

Then over on the Mintylamb site the same engine produces 118bhp

http://www.mintylamb.co.uk/?page=triumphcompare.php

It's been a busy day and I'm tired so have I missed something simple?

Bradley.

[GT6 M]

Quoted from Bradley1500

Been looking up the specs of the 2500S Engine and found some contradicting information.

On the CT site it states the S engine produces 99bhp.
ordinary 2.5  always thowt S was 106

[Sorry, link no longer available]

Then over on the Mintylamb site the same engine produces 118bhp
Nett HP of early 2.5 PIs till 73 i think, 132 Gross

        

http://www.mintylamb.co.uk/?page=triumphcompare.php

It's been a busy day and I'm tired so have I missed something simple?

Bradley.

[69vitesse]

106BHP

[Clive]

Doesn't really matter, I thought it was about 110bhp though.
What is important is that it has the very soft "caravanner's" grind of cam, and the head is pretty low CR. And smallish valves to boot.
I ran one in my vitesse for about 8 years before I fitted a TR6 bottom end (identical except the cam) and a late GT6 head to get better CR. Quicker certainly
So the actual engine is pretty irrelevant, they can all be played with to get whatever spec you want, and the parts are not expensive either. Only thing really is the cost a a cam and replacing worn components/machining.

[69vitesse]

2500 with a late hi comp head and the Vitesse/pi cam should be good for a genuine 125BHP

[AlanChatterton]

2500TC was 99bhp, 2500S with different head and cam was 106bhp.

Stick a witor special cam in, with the right needles gives about 130bhp.

[Bradley1500]

Thanks everyone for the replies.

Just wanted to know what I was starting with, so to speak. So it seems 106bhp was standard for this engine?

I assume the S engine ran Stromberg carbs as standard? Just wondering cause this engine has SUs on it at the moment.

I was already planning on sticking a TR5 cam in and from advise here will be sticking a late GT6 head on, unless there is a better alternative?

Would it be easier to have this head skimmed to get the CR up? Although Clive mentioned this head has smaller valve, so the GT6 head is probably the better route?

The engine has been dry stored for 10years at the back this bloke workshop. He says it came out of a running car. It comes with the dizzy, SU carbs and exhaust manifold (standard). What do you people think it's worth?

While I was routing around, I also saw a bare GT6 engine block and head so I might see it he wants to throw that in as well if the GT6 head is the way to go.

Bradley.

[James]

You'll want to up the compression a bit if you go for a TR5 cam.

I'd go for a TR5 cam over anything "special" if you just want something with decent all round performance.

[Clive]

"S2 engine came with a pair of HS6 carbs.

Keep the "s" head as a spare, or sell it as they seem to fetch a premium.

"unknown" engine with ancillaries, probably

[Bradley1500]

James, not going for anything 'special' as this is for a road car, albeit a fast one hopefully, not a race car and want all round good figures. I don't want to get fixated on peak BHP.

Clive, I couldn't get a good look at the engine as it was tucked away in a corner with lots of heavy things balancing around it. I wanted to check engine numbers etc. to make sure I was getting what I was buying.

The bloke is moving to a smaller workshop which is why he wants to get rid of the engines. I might see if he wants to throw the whole GT6 block/head in as well, good for spares as you say. He wanted 250 just for the 2500 engine (with ancillaries) and I suspect it was a little steep.

This guy is running a MK2 GT6 with a 2500 engine amongst other Triumphs so he said he could advise me on modifying the sump to suite.

Also whilst we're on the subject of engines, anyone ever used one of these?

http://www.ebay.co.uk/itm/190696508238?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

Are they any good? I thought the engine would be easy to work on, on one of these as the engine can be rotated 360 degrees.

Bradley.

[69vitesse]

Quoted from Bradley1500

Thanks everyone for the replies.

Just wanted to know what I was starting with, so to speak. So it seems 106bhp was standard for this engine?

I assume the S engine ran Stromberg carbs as standard? Just wondering cause this engine has SUs on it at the moment.

I was already planning on sticking a TR5 cam in and from advise here will be sticking a late GT6 head on, unless there is a better alternative?

Would it be easier to have this head skimmed to get the CR up? Although Clive mentioned this head has smaller valve, so the GT6 head is probably the better route?

The engine has been dry stored for 10years at the back this bloke workshop. He says it came out of a running car. It comes with the dizzy, SU carbs and exhaust manifold (standard). What do you people think it's worth?

While I was routing around, I also saw a bare GT6 engine block and head so I might see it he wants to throw that in as well if the GT6 head is the way to go.

Bradley.

If you can get the GT6 cam, go with it. Less lumpy and more drivable than the TR5 cam and still gives very good power.
Be careful not to overtune the engine, very easy to do as the previous owner of mine did, all the toys, tubular manifold, TR5 cam etc... Flies above 3,000, but a PITA around town as it comes off cam under 40 odd in top.
Even 125BHP will make any small chassis car pretty impressively quick even by modern standards, that's 0-60 in 8 seconds territory, go much above that and you need to start considering means of slowing it down better and the general hnadling/transmission.

[Bradley1500]

Quoted from 69vitesse

If you can get the GT6 cam, go with it. Less lumpy and more drivable than the TR5 cam and still gives very good power.
Be careful not to overtune the engine, very easy to do as the previous owner of mine did, all the toys, tubular manifold, TR5 cam etc... Flies above 3,000, but a PITA around town as it comes off cam under 40 odd in top.
Even 125BHP will make any small chassis car pretty impressively quick even by modern standards, that's 0-60 in 8 seconds territory, go much above that and you need to start considering means of slowing it down better and the general hnadling/transmission.

Really, the TR5 cam? I thought it was a good drivable 'warm' cam, not anything silly?

I was hoping for around the 150 mark with the mods I've got planned, so the car should go really well. I'm going the EFI route which from all accounts can make even really wild cams behave themselves on the road. So thought the TR5 would be fine.

Don't worry I've thought about the rest of the drivetrain and braking/handling.

Bradley.

[69vitesse]

With EFI, the TR5 cam will be perfect, it was after all intended for fuel injection.
But carbs? Just a bit to 'fierce' for a comfortable round town experience.

[James]

I've driven a couple of cars with a TR5 cam on carbs and they're fine - a couple of those were in heavy saloons.

It really isn't going to be an issue in a lighter GT6

Just make sure you get the compression ratio right and you'll be fine.

[Gt6s]

I would not be too hung up on tuning up the 2500 S engine.

Fit a full set of bearings.

A modified Gt6 Vitesse sump AND DIPSTICK !!

The HS 6 carbs on Gt6 opened out manifold. And dump the waxstats.

A decent exhaust system.

A pair of K&N's.

They go allright in a Gt6 like this, I have A Gt6 and a Sixfire both like this.

[Gt6s]

If you do decide to swap the head for a late 2ltr or early 2.5 do not forget to get the pushrods that go with it.

[Steve P]

I have a 2.5 Vitesse with a TR5 cam on HS6 carbs,not lumpy at all if set up properly,i`m running a CR of 10:1 with a little breathing work on the head and a tubular manifold.

It will pull from 1000 rpm in overdrive top no problem and peak power was 173 bhp at 5500 on the rollers.
Steve

[Bradley1500]

Thanks everyone for the advice.

I think I've decided on the spec of the engine.

With a late GT6 head on what sort of CR would I be looking at?

Steve P, that's a really good result especially as you're still running on carbs. I was only expecting around 150bhp and I'm planning on doing more engine work than you have. Should produce some good figures.

Also has anyone used one of those engine stands I linked to earlier?

Bradley.

[Richard B]

Quoted from Bradley1500

Also has anyone used one of those engine stands I linked to earlier?

Yes but not that impressed with it.


For the Stag engine I built one that bolts to the sides rather than the endplate.

[Nick Jones]

I've got a 6 pot block hung on an engine stand right now.  What I've done is made an offset plate that picks up on the engine mount pad (as used on GT6/Vit/TR6) so that the block is mounted sideways on with the engine stand pivot point pretty much in the centre of the block.  Easy to spin to whatever position and both ends of the engine are left free.  Less load on the engine stand this way at the weight of the block sits much nearer the pivot point.

Bare block weighs about 70 kgs, short engine about 120 kg.

Nick

[Bradley1500]

That's a shame, Richard, as I've just bought one.

It didn't cost the earth so I'll give it a go and see how I get on with it.

Thanks for the info Nick.

The engine stand I bought says it good for up to 350kg so hopefully it'll cope fine.

Bradley.

[Deleted User]

Quoted from Bradley1500

That's a shame, Richard, as I've just bought one.

It didn't cost the earth so I'll give it a go and see how I get on with it.

Thanks for the info Nick.

The engine stand I bought says it good for up to 350kg so hopefully it'll cope fine.

Bradley.

You can do as Nick as done I did the same and used the same stand as you have bought so just use it they are all much the same.

[Nick Moore]

Bradley, the engine stand may say that it's rated to a third of a tonne, but that's only the weight the stand can take. Don't hang your engine off the backplate as it will bend, and then you will start breaking clutches.

[Gt6s]

Quoted from Nick Jones

I've got a 6 pot block hung on an engine stand right now.  What I've done is made an offset plate that picks up on the engine mount pad (as used on GT6/Vit/TR6) so that the block is mounted sideways on with the engine stand pivot point pretty much in the centre of the block.  Easy to spin to whatever position and both ends of the engine are left free.  Less load on the engine stand this way at the weight of the block sits much nearer the pivot point.

I did that too.

[Bradley1500]

Sorry I didn't read Nick's reply properly before I posted.

Advice taken on board I'll mount the engine the same way as Nick has.

Don't suppose you've got any pictures of the engine mounted, having trouble picturing it.

Bradley.