Engine modification gains.

[eddietiv1]

As a follow on from my childhood dreams photos,the car as had a few engine mods as listed`

 

3 WEBER 40 DCOE CARBURETORS.

 

CYLINDER HEAD BY ROLLING ROAD AUTOTUNE.

 

CRANKSHAFT,CON RODS,FLYWHEEL,LIGHTENED BY WILKINSON DYNAMIC BALANCING.

 

CAMSHAFT BY KENT CAMS,REF TH5.

 

FULL FLOW 6 BRANCH STAINLESS STEEL EXHAUST.

 

DISTRIBUTOR ADVANCE CURVE BY ALDON AUTOMOTIVE.

 

RED TOP HIGH CAPACITY FULL FLOW FUEL PUMP.

Thats from the list that ive got in front of me,so what bhp would i be expecting to get from these mods.Are these the typical type of mods,top end acceleration is very lively.Please enlighten me as im new to these cars,cheers.

[dblenk]

Eddie

welcome to the forum, your car looks great

 

i am embarking on the same however a piper 285 cam, i am looking for around 125 / 130 BHP at the wheels

 

my present form states 82 bhp at the wheels

 

its worth the £40 for a rolling road run out, but all RRs are different thats why i am stating the 82 then the mods give me a figure which will give a percentage increase if you get my drift

 

cheers

 

david

[foster461]

As a follow on from my childhood dreams photos,the car as had a few engine mods as listed`

 

3 WEBER 40 DCOE CARBURETORS.

 

CYLINDER HEAD BY ROLLING ROAD AUTOTUNE.

 

CRANKSHAFT,CON RODS,FLYWHEEL,LIGHTENED BY WILKINSON DYNAMIC BALANCING.

 

CAMSHAFT BY KENT CAMS,REF TH5.

 

FULL FLOW 6 BRANCH STAINLESS STEEL EXHAUST.

 

DISTRIBUTOR ADVANCE CURVE BY ALDON AUTOMOTIVE.

 

RED TOP HIGH CAPACITY FULL FLOW FUEL PUMP.

Thats from the list that ive got in front of me,so what bhp would i be expecting to get from these mods.Are these the typical type of mods,top end acceleration is very lively.Please enlighten me as im new to these cars,cheers.

 

 

I would think, depending on the details like compression ratio and what was done to the head that you would be between 110 and 130 rwhp and that should be a lot of fun to drive.

 

Stan

[jellison]

I would think, depending on the details like compression ratio and what was done to the head that you would be between 110 and 130 rwhp and that should be a lot of fun to drive.

 

Stan

 

What! - That is a fair amount of mods and if done well would be about 175-180bhp at the fly, which would be more like 150rwhp.

 

I'd say if it is all setup right (jetted on a decent set of rollers) that you should have the engine sorted.

 

I'd concentrate on the rolling chassis - i.e. what Diff is in it LSD or std, (either ok at this level or grunt), what final drive CWP does it have? You will want it up from the way to long std UK 3.45. A US Std 3.7 would be good, but at that level of performance I'd pop in a 3.9, you will not loose top end as you just bang in the OD earlier and the .8 OD ratio is hardly going to be pulling top revs even with another 50bhp.

 

What suspension and springing does it have, std bushes, poly or even more nyaltron type?

 

You will want some decent pads as the stoppers at these power levels and std ish weight can make you run out of brake if really pushing it HARD, though that might not be to likely on the road - but if you fancy tracking it or do drive proper fast, then some Hawk Blues should be up to it. 4 Pots and huge discs is just Bling really, unless you are very hard on brakes.

[Steve Knight]

What! - That is a fair amount of mods and if done well would be about 175-180bhp at the fly, which would be more like 150rwhp.

 

Well .... no actually. I agree with foster461. This is not much more than TR5 spec, and they rarely gave 150 bhp (at the flywheel) You need a faster cam, at least Kent TH6 which still gives docile road manners. 10.5 CR Head porting and smoothing. You may get nearer to 170bhp. It is very difficult to get power out of these engines. You cannot draw comparisons like when tuning a Ford for instance. As I have said; best power increases are to be had from the exhaust / head outlets and manifold, but not many will stick their neck out for ridicule.

Edited October 23, 2009 by Steve Knight

[jellison]

What! - That is a fair amount of mods and if done well would be about 175-180bhp at the fly, which would be more like 150rwhp.

 

Well .... no actually. I agree with foster461. This is not much more than TR5 spec, and they rarely gave 150 bhp (at the flywheel) You need a faster cam, at least Kent TH6 which still gives docile road manners. 10.5 CR Head porting and smoothing. You may get nearer to 170bhp. It is very difficult to get power out of these engines. You cannot draw comparisons like when tuning a Ford for instance. As I have said; best power increases are to be had from the exhaust / head outlets and manifold, but not many will stick their neck out for ridicule.

 

I have no idea waht is in the lump or what a TH5 spec of cam has as far as lift / duration bla bla, but it has obviously reasonable amount of work over a stoke lump. Like Steve say TR5's and early 6's did not ever have 150bhp. I think a good one would have been 140 at the fly (but cars then only weighed about a ton so they went fairly well.

 

Ideally you need to fine if the head is based on a 125 head or the 150 one which has larger valves and with some porting and raising the CR (again as Steve says to about 10.5) running on 99 octane with a goo fast road cam and either tweek Fi or the 40 Webbers you have set up right you can end up with 170+bhp. I have had most states of tune from a tired 125 lump all the way to Full Steel (silly money) race 6's, but you can have alot of fun with the spec you have - I'd just get the fuelling checked at a good set of Rollers (that can tweek Webbers) and enjoy it. I would not chase more power (well not for a while) just enjoy it.

[Guest ntc]

Hi Steve/Jon

Read his last comment I bet from the lights it ain't that quick

[fastlorrytr]

Nice engine specs! What CR?

 

Today, after 4 years I finally drove my TR6 again with a fresh engine, similar to yours with 1.65 roller rockers, 10.25CR and worked head.

So, this afternoon it was on the rolling road adjusting the webers and ignition timing. The guy from the rr was expecting 170 bhp and about 170 nm torque.

After 3 runs it did 178.8 BHP @ 5.300 and 240 nm torque @ 5.090. The advance curve is not optimal and I'm still using points, so he advised to alter this, running it in another 800 km's and come back for a finetune. Like I said I drove it again after 4 years with this fresh modified engine, but was really amazed by the torque!! Good luck with yours!!

[Alec Pringle]

The power output as such doesn't matter - what's important is making sure that the consumable components are in good condition, then putting the car onto a rolling road with a competent operator . . . . able to make the most of what you've got by virtue of judicious fine tuning.

 

Most of the talk of 160, 170, 180, 190bhp road engines is so much bullshit. Tales of mystery and imagination. Bolting on expensive gewgaws doesn't in itself make lots of horses. Only care and attention to detail does that. I know how much care, attention to detail and man hours were required to blueprint a prodsports TR6PI engine past 150bhp (flywheel) some 30 years ago. Working weeks, not days. It's an expensive exercise in terms of time expended. As is reducing losses elsewhere in the drive train. At the time there were supposed "200bhp" triple-webered 6s around, that couldn't live with mine. They might potentially have been capable of putting out 200 horses, but in reality were a long way from that. Since then I've driven a few 6-pots with supposedly exotic power outputs, but which I'd rate at no better than 20-25% less than the claimed bhp. Some engine builders must dream telephone numbers.

 

As a comparison - my wife's TR8 puts out an awful lot of horses. No, I don't know how many. Enough to be frightening. The engine was built by a very good engine man for his own satisfaction. Apart from £6K of components and the sub-contracted machining etc costs, that soaked up 500 skilled man hours. At current commercial rates, that's the thick end of £30K all in. Law of diminishing returns, every extra horse costs that bit more in time, effort, money.

 

All that really matters is that the owner enjoys driving his car . . . . the figures are worth about as much as the paper they're written on.

 

Cheers,

 

Alec

[88V8]

....attention to detail and man hours were required to blueprint a prodsports TR6PI engine past 150bhp (flywheel) some 30 years ago. Working weeks, not days.

Yes.

After all, what does 'blueprinting' mean? It means you're building to the optimal clearances and tolerances. Not over not under.

So you have to measure everything.

With some components, dimensions can be accomplished by machining, but not if you want to make something bigger. If you want a component that's a few thou bigger than the one you have, you have to sort through a parts bin, measuring until you find what you want. Think of a crank - the dims of all the journals, the run-out.... And then perhaps you have to machine it down a tad, and then machine or select counterparts to match. And of course if parts should have a hardness - cam followers, cams - they have to be Rockwell tested.

And everything stressed has to be crack-tested. After you've gone to the trouble of selecting it for dimension.

As you say, hours and hours and hours.

 

Perhaps that's where Fastlorry's engine has been for four years, those are good dyno figures.

 

Yet, in contrast, how many engines get built with the piston rings not even gapped? From the outside, from the spec of parts, one wouldn't know.

 

My engine was blueprinted in 1978 by Brian Heppenstall at the premises of Brian 'Yogi' Muir. They had a name at the time. Hopefully it was properly done. But I've no idea. I doubt it cost the equivalent of £30k. The second owner told me he used to rev it to 7,000. Not me, thanks, I wouldn't dare.

I'm just thankful that it starts and runs on all 6.

 

Ivor

[jellison]

The power output as such doesn't matter - what's important is making sure that the consumable components are in good condition, then putting the car onto a rolling road with a competent operator . . . . able to make the most of what you've got by virtue of judicious fine tuning.

 

Most of the talk of 160, 170, 180, 190bhp road engines is so much bullshit. Tales of mystery and imagination. Bolting on expensive gewgaws doesn't in itself make lots of horses. Only care and attention to detail does that. I know how much care, attention to detail and man hours were required to blueprint a prodsports TR6PI engine past 150bhp (flywheel) some 30 years ago. Working weeks, not days. It's an expensive exercise in terms of time expended. As is reducing losses elsewhere in the drive train. At the time there were supposed "200bhp" triple-webered 6s around, that couldn't live with mine. They might potentially have been capable of putting out 200 horses, but in reality were a long way from that. Since then I've driven a few 6-pots with supposedly exotic power outputs, but which I'd rate at no better than 20-25% less than the claimed bhp. Some engine builders must dream telephone numbers.

 

As a comparison - my wife's TR8 puts out an awful lot of horses. No, I don't know how many. Enough to be frightening. The engine was built by a very good engine man for his own satisfaction. Apart from £6K of components and the sub-contracted machining etc costs, that soaked up 500 skilled man hours. At current commercial rates, that's the thick end of £30K all in. Law of diminishing returns, every extra horse costs that bit more in time, effort, money.

 

All that really matters is that the owner enjoys driving his car . . . . the figures are worth about as much as the paper they're written on.

 

Cheers,

 

Alec

 

500 man hours! An engine only takes to long to machine and build - that is nuts and they clearly were pulling your chain. I am having a no limits engine built in t he US by a very well respected V8 building (just finsihed very high up in his first time of entering a national engine build off competition) and from knowing how many hours are going into this you 500 hours is just stupid.

 

the engine we are talking about is what most would class a fast road engine, from what is in it. But way way from a race engine. i.e.it using largely std internals. Webbers mean nothing on there own and the one here are 40's which is ideal for a fast road engine (full silly monet spec race ones can handle 45's and get the most from them - but not for a fast road engine).

 

As an example of a total waste of cash on an engine, I was at the SPA 6 hours event a few weeks back and parked next to a chap that had thrown 10k at having his TR5 lump tuned into something close to full race. He has only been racing a few years and has just bought one of the top fia TR4 as well so knows how fast a top tuned 4, 5 or 6 can go. And (after having a chat about how he was REALLY Unhappy with the build as he though it was WAY WAY slower than his fantastic fia 4) so I said lets warm it up and I'll take it for a spin around the local roads for a few miles to see how it was (this is alledgedly a full house race engine, carrilos, full race cam, 45 webbers, proper pistons roller rockers - everything bar a steel crank (which is only there for those really big top end revs). Holy ****, it did not rev, it was a total joke, I recon he had been totally stiffed - it was way slower than a std engine. And the burk that had built it recon'd (with no sheet for rollers to back it up ) it was making 220bhp - I said I doubt it had 12-3 - 130bhp!

 

I have recommended he take it (after finding waht cam is in it) to a tuner / rolling road specialist that we use (as he set our racer up and our is 225+ on a very conservative new state of the art set of rollers).

we use once he has the spec of the cam and the timing then he can have what he has checked over (at not much cost) to optimise what he has as something is clearly not right (though it finished the 1 hour race). Set the cam timing properly, and set the dizzy and and check over all the webbers jetting etc. Get a before and after and take it from there. If it is still useless get back to the person you handed 10k to and present them with the facts.

 

We gave up on having our engines built by outside people years ago - you simply do not know what you are going to get, unless you can afford the best (for me I'd only ever use John Wood or Mass). We have has supposedly top TR people do our engines and they were shot after a race or two - i.e. they did not know what they were doing (I'd love to say who but hardly adviseable)!

 

We used to run a fast road engine with 158rwhp / ~175ish fly bhp and that, just well put together bottom end with std rods, pistons and crank, but all blueprinted and balanced, but alot of effort in a highly ported 150bhp head with 10.5 CR and it really kicked but for 4 years on the road and track before we stripped it (all fine) to go the money no objetc roure (but building ourselves by machining).

 

We are basically taking alont of flannel here as we do not know if the car already goes well, and hence does not need touching! All he should do IMHO is take the engine / car to a person like we recommended to the racer chap we know and get it properly check over - it could be spot on, or it might just need optimising - AND THE JUST DRIVEN AND ENJOYED!!!!!!!!!

 

Oh ya and most big power numbers for seriously modded TR lumps (anything over 230bhp at the fly is just wishful thinking). We spent 1100 quid just on a one off tubi exhaust to be built for the car (it had a Pheonix system on it before which is fine for most instances) - but the gains this made after being resetup we amazing (virtually no more power - but the torque made MASSIVE gains - like having another 1/2 - 1 litre of stump in the car. This does not really have any bearing here, but show you really do need the right bits and it is all about having it setup by people that know what they are doing ontop of a Bloody good build.

 

Just enjoy it. And lower the final drive.

[Alec Pringle]

Hi Jon,

 

I agree, 500 hours is a stupid amount of time to put into an engine, but if you're a perfectionist with time on your hands it's not hard to achieve. Once you get into lightening, balancing and blueprinting every, and I mean every, component on the engine, modifying just about every component that can be modded, adding a two stage Nitrous installation and the plumbing that involves, a fiendishly complex ignition/management system, all on a one-off basis . . . . The attention to detail is so terrifying, I'm surprised the man didn't spend more time. That's obsession for you, but drag racers do seem to get more carried away than circuit racers. And as for the wiring and dashboard, I don't even want to guess how much time and money that work of art soaked up.

 

Cheers,

 

Alec

[Red 6]

As a follow on from my childhood dreams photos,the car as had a few engine mods as listed`

 

3 WEBER 40 DCOE CARBURETORS.

 

CYLINDER HEAD BY ROLLING ROAD AUTOTUNE.

 

CRANKSHAFT,CON RODS,FLYWHEEL,LIGHTENED BY WILKINSON DYNAMIC BALANCING.

 

CAMSHAFT BY KENT CAMS,REF TH5.

 

FULL FLOW 6 BRANCH STAINLESS STEEL EXHAUST.

 

DISTRIBUTOR ADVANCE CURVE BY ALDON AUTOMOTIVE.

 

RED TOP HIGH CAPACITY FULL FLOW FUEL PUMP.

Thats from the list that ive got in front of me,so what bhp would i be expecting to get from these mods.Are these the typical type of mods,top end acceleration is very lively.Please enlighten me as im new to these cars,cheers.

 

 

Difficult to say as others have commented but for what its worth with this setup you will get a spirited driveable car which sounds like a proper British sportscar and therefore negates the need for bhp or torque figures.

 

You will still be blown away by ford mondeos, audi's golfs and renault clios but they will be looking at you as they pass with much envy.

 

The real limitation to tuning is the cylinder head design. You can only do so much with a non crossflow head and a single cam and as Jon has alluded to get real power you need lightweight components to reduce the reciprocating mass so the engine revs quicker and higher, but then due to the engine design the a longer duration cam is required which moves the power band upwards, and pulling away from the traffic light at 3krpm can get a little tireing after a while.

 

You could consider making better use of the power at your disposal. Get rid of those heavy steel panels for plastic ones and no one will keep up! (ok an exaggeration perhaps but it will feel like it).

 

One last idea is to get rid of the dizzy and webbers and instal throttle bodies (they will fit your manifold) and an engine management system like emerals or omex. Either will give a noticable improvement at a £cost.

 

Welcome to the world of upgraditus.

[jellison]

Difficult to say as others have commented but for what its worth with this setup you will get a spirited driveable car which sounds like a proper British sportscar and therefore negates the need for bhp or torque figures.

 

You will still be blown away by ford mondeos, audi's golfs and renault clios but they will be looking at you as they pass with much envy.

 

The real limitation to tuning is the cylinder head design. You can only do so much with a non crossflow head and a single cam and as Jon has alluded to get real power you need lightweight components to reduce the reciprocating mass so the engine revs quicker and higher, but then due to the engine design the a longer duration cam is required which moves the power band upwards, and pulling away from the traffic light at 3krpm can get a little tireing after a while.

 

You could consider making better use of the power at your disposal. Get rid of those heavy steel panels for plastic ones and no one will keep up! (ok an exaggeration perhaps but it will feel like it).

 

One last idea is to get rid of the dizzy and webbers and instal throttle bodies (they will fit your manifold) and an engine management system like emerals or omex. Either will give a noticable improvement at a £cost.

 

Welcome to the world of upgraditus.

 

Throttle bodies and all that goes with getting them setup will really cost and 40 webbers ar ea nice compromise for a fast road TR 6 cylinder lump.

 

Yep only so much you can do with the old TR non-cross flow lumps (at least they have 8 port unlike and MG though!). Alos piston area is ann issue on the 6's more than the 4 pots (as you can get in whopping great piston on the 4's). Think that made the single biggest difference to our engine (once already full race / steel) was the trick equal length manifold. If you coul stretch to one of these (ours was a one off), I'd just get it all check over (i.e. what you have is running as best it can and put a shorter final drive in.

 

Not much used to be able to hang with our 175bhp Roadsports spec 6 when it had a 3.9 in it! Not had it on the road in it current spec!

 

But my 4 will be back on the road in 1 or 2 weeks after 3 years off it! Can't wait...