Upgrades For A N/A 90 elan

[PhilD]

Ive recently brought a N/A elan 1990.

Lots of upgrades have been suggested to get more BHP:

1. Throttle bodies
2. Air in take
3. Bike Carbs
4. Chips
5. Exhaust
6. Turbo

Can anyone advise mostcost effective route to additional horsepower

Thanks

[Gary]

I'd go for no 6

[GeoffSmith]

Phil,

Clemo is the N/A champion on LEC - see here.

Geoff

PS I suppose you could buy an SE engine.......

[Doug]

Can anyone advise mostcost effective route to additional horsepower

Thanks

NOS

[dapinky]

All the options are quite expensive/difficult to achieve easily.

The turbo isn't just a 'bolt-on' option as the pistons and other internals are different on an NA and an SE.

NOS can be done for less than £500 (a lot less, if you know what you're doing - i fitted a system to my other car for about £160 - 4 seperate injectors - and it took me less than a day (admitedly, the intake on a Triumph is easier to remove than on an Elan, but it should still be a weekend job).

As previously mentioned, an SE engine may be the way to go, but again, there will be other bits to get (ECU, wiring etc).

Also bear in mind that the gearbox internals are a bit different on an NA, so it still won't be exactly the same (better acceleration though!)

This option will still 'only' give you 30-40 bhp increase, unless you also fit a chip (£200 for a switcher unit).

To be honest, unless your car is mechanically rough, the engine swap is probably not worthwhile, and you'd be better off selling the car and buying an SE/S2.

Personally, I'd go for the NOS option, with a 50bhp set of nozzles. The NA is okay to drive anyway for more than 95% of the time, and you'll have the extra bit if you want extra accelleration!

[PhilD]

Sorry guys, I'm new to this, what is NOS?

[dapinky]

NOS = Nitrous Oxide (laughing gas!)

Its injected into the intake manifold (along with extra fuel, hence a 'wet' system) and then breaks down into its constituent molecules, giving more oxygen and therefore a bigger bang (very simplified explanation!!!) It also cools the charge, making it more dense = more fuel = bigger bang.

For lots of information look HERE. They aren't the cheapest, but they're meant to be pretty good (UK's biggest/best seller!).

By shopping around you can get a full system with 8 jets (4 fuel, 4 gas), a manifold splitter (to send gas & fuel to each jet) 2 selenoids, bottle and pipes for less cash, but a 'ready to go' system has got convenience if you aren't sure what you're doing.

A programable controller is worthwhile, but they can be bought seperately (or built if you can understand a wiring diragram and use a soldering iron!) afterwards - i just use a WOT switch.

[rip]

Superchargers are apparently more retro-fittable than turbochargers, so that may be an option. I would expect this to be quite a lot of work though.

I agree with Dapinky. Appreciate your N/A for its handling (you can push it harder round bends because you have no turbo to cut in and throw you sideways), or change it for an SE.

[rip]

And if I had an N/A instead of an SE, I would keep it.

[ESM]

Sorry I don't chips for the N/A largely because I don't have one to do the development on.

If I was sent a copy of the PROM I might be able to have a look but ultimately it'll need modification of the spark tables through lengthy dyno sessions. Its much easier to make power gains on a turbo because you can simply turn up the boost.

[Nige]

Well I have an NA that could be a Guinea Pig , mind you I might struggle with the extensive dyno time, as time is a commodity I seem to have little of at present.

There is a chap in the states whose name eludes me at present but is an occasional poster here who has an NA as a track car, I don't know what mods he has done if any but it might be worth asking. My understanding is that the engine will respond well to 'traditional' tuning. Better breathing through porting and flowing the head and connected bits and pieces such as air intake and exhaust. After that you are then looking at fuel delivery and ignition mapping. Cam profiles will also be a significant factor, as ever power will come at the expense of driveability. The NA has a smaller clutch than the SE or S2 so it does not have the same power delivery capability, I would fit an SE clutch as we know they are good for over 200BHP. The lower gears are shorter and the final drive is taller (I think). I have this approach at the back of my mind for my NA but it's little more than an idea at the moment, however it's a more complex and more expensive approach than winding the boost up.

[Oliver]

Blimey, this is an interesting topic, i can`t add much so far, just been trying to keep the thing running rather than tuning !

Nige, i think the gear ratios are the same as the SE, only the final drive is lower. The flywheel is smaller as well as the clutch, it must be more responsive than the SE! Less mass to accelerate.

[dapinky]

Nige, i think the gear ratios are the same as the SE, only the final drive is lower.

Yep, thats what i was told at the parts sale when i wanted to buy the complete NA gearbox they had

The flywheel is smaller as well as the clutch, it must be more responsive than the SE! Less mass to accelerate.

Unfortunately, there's a higher compression ratio to overcome as well

[Oliver]

Getting more power easily from a naturally aspirated engine is going to be more involved and expensive than doing the same with a boosted engine but i bet you could free up some more puff by losing the horrible cast iron exhaust manifold and getting a nice four branch single wall tubular item made (it would look nice as well), and getting the inlet and exhaust ports polished and matched to the manifolds. I`d do that first and leave the engine management until later.

Nige, know anyone who could make us NA sufferers a nice batch of polished stainless exhaust manifolds ?

[Oliver]

Nige, i think the gear ratios are the same as the SE, only the final drive is lower.

Yep, thats what i was told at the parts sale when i wanted to buy the complete NA gearbox they had

The flywheel is smaller as well as the clutch, it must be more responsive than the SE! Less mass to accelerate.

Unfortunately, there's a higher compression ratio to overcome as well

Oh yes, i forgot about the C/R.

[Oliver]

Sorry Nige, i just saw your comments about porting / polishing, been on the Old Speckled Hen, Please forgive me for repeating you
but generally speaking, we need and engineering approach to getting more power, as opposed to a chipping / wastegate modding one.

[ESM]

There is also a place for this kind of thing combined with chip mods or perhaps simply advancing base timing...

[PhilD]

Thanks for the ideas guys. I guess adding something that I can reverse would be quite appealing in - case I ever want to sell it on. More questions...

Has anyone ever fitted a supercharger? If so what type and what were the results.

Is there a chip anyone has fitted?

What intake or exhaust mods would you recomend?

Thanks

Phil

[Nige]

According to the Mark Hughes book the gear ratios are indeed the same and only the final drive is different (SE 3.833:1 and NA 4.117:1) Clutches are indeed different sizes ( SE 225mm and NA 215mm).

I see the higher compression ratio as a potential problem if turbo or supercharging as a combination of high compression and forced induction will rapidly lead to knock. However, if traditionally tuning an NA the higher compression ratio is a positive advantage.

[rjwbrown]

There are some issues with any engine turbo or N/A when increasing the power from stock.
Turbo engines tend to produce their power at higher rpm than N/A due to the turbo but you still have to take the bottom end in to consideration.
220hp was always considered the limit of the "red top" vauxhall engine with the standard bottom end but 270/280/hp is possible with an all steel bottom end and forged pistons,but that is about the limit with N/A engine even the Ford BDG maxed out around the same figure.
Taking that the elan engine is 1600 cc I would see the max power around the 220hp mark but the engine would need to be highly modified
e.g. all steel bottom end and forged pistons a head gasket change + modified cams and probably solid lifters. also you would need to change the stock inlet for something like throttle bodies with a programable engine management system (luminition is one that springs to mind)
The development costs would far out weigh the results, competion engines of this specification cost £30,000 + I know i have built them
Coswoth BD bottom end bolts costing £120 a set thats £15.00 each and pistons £100 + each never going to be worth it in a road car.

I have also done trick red top engine N/A for competion use puting out 280hp N/A but again the cost was high around the £20000 mark
All steel bottom end Swindon race engines cams and running gear etc max power around the 7000 rpm mark and have seen the engine rev to 10000 under power.

trial and error can be a costly exercise in attempting to gain more power!