Supercharging a 1256

[viva2300]

Port the head, then turbo it....half the boost for the same go....might save the engine.
You've still got to make the bottom end strong however you go about it....so money to spend.

[1303r]

ok.
so start with a stock 1256, give yourself a budget of say £300 to get it faster. without changing out the engine for a ohc. how would you spend it and what gain would you get?
for me, i'd buy a used blow throu carb and intake piping £30
used t2 turbocharger £50
used, injection fuelpump £10
new high pressure fuel lines and clamps £30
fuel pressure reg £40
boost retard device, used/new dual vacume canister £10?
large bore exhaust and clamps/gaskets £130
obviously you'd need to check fueling so either a wideband o2 sensor or book a dyno tune. really need this whatever tunning you do anyway.
so, all that with no internal mods, thou sump needs removing to make an oil return. i'd think a power increase of 40% should be very easy. so 80bhp ish, with shed loads more torque and no need for extra revs. obviously more power is availible but your going to need to sort out the bottom end and headwork first.

how far can you go with £300 N/A tunning?

[viva2300]

If 80bhp is your limit, then i'd say ok....i thought you were maybe looking for more than that.
Go for it i say.....it will be good to see how it pans out.
If the project works well, then i reckon theres a market ready and waiting for it, reason being the 1256's are not worth much really...not something i agree with, but...well...so it would be cheap and cost effective tuning for the owners....

Paul

[pbottomley]

This £300 will become £600 and your 80bhp will be 65bhp if your lucky ... you fail to see the benefit in internal work and seem hell bent on the barry boy approach of bolting things on in some vain attempt to make things work.

As for viva2300 if 1256's are not worth anything then please feel free to collect up a dozen and post them to be....

so put up or shut up I say to the both of you

[simon cummings]

Well,I think we are all in agreement that we only play with ohv engines for the fun of it!
You have got to want to do it,you certainly dont need to!
Bang for buck? for my £300.00 I would drop in a 2.0 pinto 100bhp, but thats just me.
Halfway through laying under a Magnum 1800 in a breakers years ago,removing the axles and rear trailing arms it occured to me that I should have just bought the whole car and put it on the road, like I said before we do it because we want to, not because we have to.
Slap a turbo on by all means,you know you wont rest until you do!!
It would have to go very tits up to only make 65bhp though,or am I wrong in thinking they made 60 ish in the first place Paul?

[Icedmunkie]

I am inclined to to agree with Paul on this one, the method your going to down to turbo seems rather erm how do I put it, not thought through.

I have been toying with the idea and have shelled out money rebuilding my 1256 with new bearings, pumps, etc as i was going to supercharge the engine but realised that the overall cost would not be beneficail, whereas you can pick up a turbo alot cheaper and it would in some respects take lots of work. I have done a fair bit of research and feel your approach is totaly wrong, look into it more and see the development that has gone into turbo engines in the past... RS turbo, Renalt 5 GT's etc. I have been talking to guys at Ricardo's who develop and build engines for performance cars and they have said its not a 5 minute job of just wacking on a turbo, adding a bit of pipework and turning the boost up. At the end of the day turning the boost up will only do so much. Its still a small engine, which isnt really designed for massive amounts of tuning (Sorry Paul) but like has been said its fun, hence why I am doing it.

I was going to use ARP Bolts but decided there not worth the extra money, so far i have sent my head off to a chap i know up north who is a bit of a genius with them for different valves, new seats oil stem seals as well, then a good dose of porting and polishing will be next.

As for the bottom end, its getting balanced but probably not lightened, i have heard different points on lightening the crank as its a 3 bearing but interested to know more about these bearings Paul B you mentioned!

Where were you thinking of getting the oil feed from the turbo from? Have you thought about the oil pump itself being up to the job of cooling the turbo as well as the engine.
You have made no mention of an intercooler or oil cooler, which if i did it (and I am sorely tempted to) would be fitted.

Sorry for the rant but feel you may have missed crucial points, and wouldnt want to you spunk 300 quid on something that isnt thought through, also if your putting more power thorough and engine isnt it worth rebuilding it? Its not as though its a newish engine,its worn just from normal use and if your wanting more power I get the feeling you have been ragging yours about, I know I have at times driven mine hard very hard, and almost blown it up by dropping the revs down far to quickly at high speed.

As paul said there is a limit on the revs, you can rev as much as you like but it will only give you "power" to a certain point then make lots of pointless noise which isnt even very nice to listen to...

[1303r]

yeh. ok. i don't think you realise i've done this before
turboed an old vw flat four engine with simple bolt on stuff. worked out very well for the time/cost involved
and yes i didn't mention intercooler/chargecooler. wouldn't need one with the small amount of boost i'm talking about. i do have a few intercoolers and a charge cooler set up in my box of stuff as well.
oil feed for the turbo will come from the oil warning light take off.
turbo will be water cooled.

to be honest, your talking a lot of **Bleep**. i have thought it through, i've been down this route before .

i'm not saying this is the best way to improve the performance of the viva. a OHC swap would be easier and get more power per pound note.

[1303r]

calm....
here's a couple of pics of my last turbo project. 1.9 waercooled flat four i jamed in a beetle. low budget but a lot of fun. resulted in a 15.5 second 1/4 mile time at santa pod, full weight car, full tank fuel and drove there and back fine. was my daily till i sold it.




http://www.youtube.com/watch?v=2EFcxyw3ZLw
http://www.youtube.com/watch?v=g1V6l_3Z ... re=related

[hbpeter]

Anyone thought what all this extra power/torque is going to do to the poor old gearbox and axle? The ohv stuff isnt the strongest. I say build the engine and lets see what happens, its your money and car.

Peter

[1303r]

obviously an increase in power/ torque will put more strain on both the axle and gearbox. as always thou it will depend on how much power we're talking about.
just because wer're talking forced induction doesn't mean we have to ring every last bit of power possible out of the lump does it?
would you ask that question if we were talking normal N/A tunning?

i can't answer as i don't know the limits of a viva gearbox or axle. axle could be swaped with a OHC axle but the gearbox/clutch would be the weak link i'd have thought.

best thing to do would be buy a modern car with power and comfort aye?