The good old days ?

If I were to build an NA lump to a budget, it'd be with these ingredients:

Volvo B280E cams, rockers and throttle body
Any 3 litre donor for intake manifold, block and heads (except Laguna so you get a distributor)
24v pistons (which I know you have a set of cos they used to be mine
GTA flywheel, trigger modified so the Adaptronic can read it
GTA timing and rocker covers, ancillaries etc.
Any free-flow zorst of your choice. Might even be tempted to suggest these headers for what they cost



This is very much a "bitsa" engine, and it ain't gonna win any prizes but the expensive stuff (exhaust, ECU) will be equally useful on whatever else you decide to do in the future. You'll have a compression ratio of over 10:1, the wildest production PRV cams with bigger valves and more capacity and the largest production throttle.

Just be careful you don't get valve clash, if so, get the pistons pocketed.

Here's one I made earlier ....

OK sans OVLOV bits .....Custom cams mind

hydraulic or solid tappets?

Solid

Hmm. odd-fire camshafts. Have you checked the valve timing? is the sprocket pin definitely offset by 15 degrees, or have you timed them up manually?

Just curious

I'll get back to you

Many years ok I read about a supercharged oddfire gta in New Zealand if my memory serves me (unlikely ) making over 400 ft/lbs.

i think best value transplant for an odd fire is the 2.8 from the Renault 25 and I think early Espace. Should drop straight in, tweak the injection , decent exhaust and induction 180 bhp and excellent mpg and no shite carbs.

If I were to build an NA lump to a budget, it'd be with these ingredients:

Volvo B280E cams, rockers and throttle body
Any 3 litre donor for intake manifold, block and heads (except Laguna so you get a distributor)
24v pistons (which I know you have a set of cos they used to be mine
GTA flywheel, trigger modified so the Adaptronic can read it
GTA timing and rocker covers, ancillaries etc.
Any free-flow zorst of your choice. Might even be tempted to suggest these headers for what they cost



This is very much a "bitsa" engine, and it ain't gonna win any prizes but the expensive stuff (exhaust, ECU) will be equally useful on whatever else you decide to do in the future. You'll have a compression ratio of over 10:1, the widest production PRV cams with bigger valves and more capacity and the largest production throttle.

Just be careful you don't get valve clash, if so, get the pistons pocketed.

Martin, dont mind if I call you that do you Petal ?

I know the 24 valve pistons are supposed to be a much better quality piston, I assume from your remark about clashing valves means that this piston will give the engine a taller compression ratio. I realise this will give more power, however, I was thinking of using the standard pistons as they will leave the compression ration suitable for Super charging a little later down the line, I think the CR is 9.1 which I believe I read somewhere was ideal for super charging. Are the standard pistons really not up to it or was the change purley for reliability and to raise the CR?

I have to be honest I would love to put together a 24Valve lump, I know Mr Faulks advised me against it but I just have a hankering to do it so I would maybe prefer to hang on to the pistons for that reason as well.

I think Richard turbo'd a 3ltr E/F lump with low boost and obtained 250bhp there abouts so the pistons cant be that bad can they, whats the difference between the 2,5 lump is it bore as well as stroke? or just crank and rods, I am assuming the pistons can't be used ?

I already have 3 branch manifods and sytem fitted to my Atmo, I was never expecting to get a reasonable gain without them, yes they did cost a pretty penny but the original equipment was blowing like the North Wind so the lot was junked; as I was not going to pay all that money for OE and gain no power!!

I have been advised that I could run the engine off a GTA Turbo ECU with sum remapping which I know can be done for now, and use a standard Renault loom to run it, I do however hear what you say about running stand alone, not sure that I would want to go Adaptronic though TBH hence the even fire choice of power plant. I dont want to be limited as to who can work with the ECU and have to travel the length and breadth of the country to do so. So maybe this would be a later edition along with a super charger....much later .

To be honest I dont want to spend any money on the engine thats in there. The plan was to maybe just rebuild a standard 3ltr EF, lump do the rings bearings gaskets seals etc and just make it reliable and leak free, since the heads were coming off maybe a little fettling maybe some valve seats and a quick clean up if thats possible, I note that Clee has put a lumpier cam in suggesting that maybe the valves are already flowing enough, so maybe its not worth doing anything else to them to keep time and money spent down to the minimum. Not the way I like to build an engine but that's what I'm stuck with for now. I need to narrow the power gap somewhat and lighten the car where possible and keep within the spirit of a road going class for sprinting and hill climbing. The trouble being is that the 3ltr lump puts me in the same league as cars like the M3 CSL which has double power. When speaking to the owner at my last sprint on the main striaght he was hitting 120mph and I was hitting 90 + mph and I was flat throught the first bend in 2nd (I found it) hugging the apex all the way so I couldnt have gone any faster if I tried he beat me by 6 seconds or something or was that Months

Even a reliable 190bhp with more top end would be nice, as a lot of the power is near the bottom of the range which is great for quick touring on A roads in tall gears but not an advantage on sprints or climbs as the engine is always reving

A bit of weight loss, and fit the coilovers to sort the handling and it will put me a little bit closer, I feel like I am over driving the car currently... well still lots to learn in all aspects.

200bhp is only 68 bhp per tonne surely that must be acheivable without too much problem on a 3ltr ?

My actual question is what can I expect to get out of a Saffrane/Laguna lump which is been de-catted, 3 branch manifolds and system, standard inlet manifold and run by a modded GTA inj ECU? Tony says 2,8 25 lump does 180 ....is 190 not a possibility withe the 2.945ltr lump?

si21

Many years ok I read about a supercharged oddfire gta in New Zealand if my memory serves me (unlikely ) making over 400 ft/lbs.

I seem to remember PeterG's car making 400ft/lbs for 5mins, along with a strange noise that he hadn't realised was the engine pinking massively before he holed a piston or two.

Ooooops.

And that takes us right back to the original subject of this thread

Many years ok I read about a supercharged oddfire gta in New Zealand if my memory serves me (unlikely ) making over 400 ft/lbs.

I seem to remember PeterG's car making 400ft/lbs for 5mins, along with a strange noise that he hadn't realised was the engine pinking massively before he holed a piston or two.

Ooooops.

And that takes us right back to the original subject of this thread

Oi dont start it was about bun fights and since neither of em frequent these pages any longer ..........

Notice the bloke who started this thread hasn't chucked any buns tho'

si21

Sounds like there are a lot of cars in development coming our racing next year.
Yip-eee

i think best value transplant for an odd fire is the 2.8 from the Renault 25 and I think early Espace.

All the FI odd-fires were K-Jet and in Renault guise were all 2664. The only 2849 odd-fires in thi scountry were in the Volvo 260 & 760 and the GTA, as far as I know (not sure about Peugeot). The Volvo engine produced 156hp (but it's very torquey)

If you want to go even fire EFI, then the Volvo B280E produced the same power as the Renault 3 litres... so playing mix'n'match makes for an interesting engine - hence my suggestion to Si.

Martin, dont mind if I call you that do you Petal ?

Call me what, dearie?

I know the 24 valve pistons are supposed to be a much better quality piston, I assume from your remark about clashing valves means that this piston will give the engine a taller compression ratio.

They have a taller dome and no pockets (24v remember) where the 12v pistons have pockets and less of a dome. As for quality, I'm not sure there's anything in it really.

I realise this will give more power, however, I was thinking of using the standard pistons as they will leave the compression ration suitable for Super charging a little later down the line, I think the CR is 9.1 which I believe I read somewhere was ideal for super charging. Are the standard pistons really not up to it or was the change purley for reliability and to raise the CR?

Okay, some thermodynamics:

The amount of power an engine generates is in direct proportion to the amount of air/fuel it "breathes in". The thermodynamic efficiency of the combustion process is directly related to how much the air/fuel mixture is compressed before ignition. This means that all other things being equal, you'll get more power from an engine with a higher compression ratio, as long as you don't go crazy and get problems with pre-ignition. The static compression ratio however is only a meaningful comparison between engines if the camshafts are the same... which they ain't.

For example, the static CR of the original Z7U is 8.6:1 and the DeLorean's NA odd-fire is 8.8:1. These figures mean very little because the camshafts make all the difference and are very different/conservative on the Z7U.

The 12v 3 litre pistons are very thin at the crown - about 2mm IIRC.

All that said, the specific output of the 3 litre PRVs is pretty poor and there are guys in the US who have successfully turbocharged their 3 litres (with even lower CR to start with) to about 8psi with no failures.

whats the difference between the 2,5 lump is it bore as well as stroke? or just crank and rods, I am assuming the pistons can't be used ?

PRV Bores come in 3 flavours - 88, 91 and 93mm
Stroke comes in two flavours - 63 and 73mm

Rods and wrist pins are different between odd and even fire.

88 bore, 73 stroke = 2664cc (early odd-fires only)
91 bore, 73 stroke = 2849cc (all the 2.8s both odd and even)
93 bore, 73 stroke = 2975cc (all are even fire 3 litres)
91 bore, 63 stroke = 2458cc (2.5 turbo)

not sure that I would want to go Adaptronic though TBH hence the even fire choice of power plant. I dont want to be limited as to who can work with the ECU and have to travel the length and breadth of the country to do so.

Things have changed a lot since the "early days". Lee's gone down a path with them and has several successful setups under his belt. I *personally* went a different way because I really wanted to avoid using a trigger wheel because the DeLorean has really limited space around the crank pulley and it screams "aftermarket" and the DeLorean crowd always want stuff to look "original" even if it ain't. The Adaptronic is the only ECU that can be triggered by the original sensor and flywheel (the flywheel trigger pattern requires a small modification). Rottbott did (I believe) around 20,000 miles on his setup before he sold it.

Adaptronic themselves have come along in leaps and bounds and their software now offers tons of features that weren't available originally. This includes the superb "Tuning by Volumetric Efficiency" which allows a driveable, useable fuel map to be set up in under 1 minute.

You really can do a hell of a lot of this stuff yourself and just spend a day on the rollers to get things perfect. I recently found a great engineering firm with all the proper kit and experience and a complete lack of bright coloured paint and cars with daft spoilers outside

To be honest I dont want to spend any money on the engine thats in there. The plan was to maybe just rebuild a standard 3ltr EF, lump do the rings bearings gaskets seals etc and just make it reliable and leak free, since the heads were coming off maybe a little fettling maybe some valve seats and a quick clean up if thats possible,

I'd say buy a running car with no MOT and whip the engine out. no rebuild necessary.

200bhp is only 68 bhp per tonne surely that must be acheivable without too much problem on a 3ltr ?

You meant 168hp/tonne. Your best bet is to see how Lee's comes together. I reckon my "mix'n'match" suggestion would hit 200.

My actual question is what can I expect to get out of a Saffrane/Laguna lump which is been de-catted, 3 branch manifolds and system, standard inlet manifold and run by a modded GTA inj ECU?

Somewhere between 170 and 200 I reckon

Cams in the 3l ....B28s with a regrind .I though they were Ren,MF had them reground .
All the same as far as I know ,odd ,even ,all out the same blanks ?
No difference on the dizzy drive position ,not sure what you mean with the 15 degree off set ?
Cams set the same in all heads for initial timing chain install then it's all down to sprockets and angles innit ??

Even fire engines have a 30 degree crank offset on one bank compared to the other to create an apprent 60 degree Vee.

So, all they needed to do with the camshafts was to provide a 15 degree offset on one of them. Hence the odd sprocket on the even fires.

The thing is, when I looked at it, (and I'm saying this entirely from memory) it seemed that the pin was not offset by 15 degrees because on both it lined up perfectly with one of the teeth - I think they are 2 teeth apart, and that ain't 15 degrees 'cos that'd require 48 teeth on the sprocket.

I could be entirely wrong, it's a long time since I looked at this stuff, so am genuinely just curious. I'd definitely want to double check with a dial gauge and degree wheel.

They could've done the even fires with equal sprockets just by offsetting where they cut the notch, so I'm not sure what's going on and I'm probably making a fuss over nothing