914 engine spec advice / opinions

[smallspeed]

I know a few of you guys have warmed over to hot 914's and so was looking for a bit of advice on what spec you went with, how it performs, etc. before I commit to a path for the type 4 build for my wife's 356..

I'm in two minds right now whether to go 2056 or 2276cc, any of them seems a good lump for a car that size and weight - I'm building for driveability and reliability not all out power, so would be aiming at say 110-120bhp for a 2056 and 140-150bhp for a 2276
opinions on performance with any of those combinations appreciated - this will prob be mated to a longer gearbox for somewhere around 25mph/1000rpm if that helps. If anyone is local ish and has a car with one of these engines in I could take a ride in, even better


Just to set the scene - I currently have a complete (in bits) 2.0 type 4 with AMC heads, so the larger valves (1.8?) and bigger ports (2.0?) combination - I will clean them up but nothing mental. Crank and case seem good, pistons and barrels seem ok (slight wear - will need rings) so potentially I could build it back up as a stock 2.0 with a cam and some balancing, but seems like "while I'm in there" going a step further would make sense! I will be running throttle bodies, efi, crank fire, no dizzy, etc.

[Mr Pharmacist]

I have a souped up 2056cc. No idea what power it gives out but I use it for hill climbing and it has plenty of power. It has racing pistons, a hot cam, it has had work done to the heads and has been blue printed etc. Its on weber, revs really freely and is easy to drive, but when you want it go it really goes. And sounds great.

If you are ever up leeds way give me a shout and I'll gladly take you for a spin

[Splitty64]

If you can afford to buy a crank go for a 78.4mm and 96 b&p's, this will give you 2270. I ran one for years with mildly worked heads and an 86b cam. I recently down specced the same engine to an 86 cam, still making 137 bhp and 150 lb/ft of torque, but power from much lower rpm. About to build a similar spec lump for my lads car, 103 b&p's, stock 2l crank, and the 86b cam, again, should be a good 150 hp motor. Lots of info out there on sites such as massive type4, Stateside tuning etc. Cooling really shouldn't be an issue, the stock cooling is the most effective VW made, my motor is run in a van so works hard and is running nothing more than the stock oil cooler.

[smallspeed]

Appreciate the input guys! I actually got my numbers wrong! 2056cc or 2257cc were the two options I was looking at, basically to avoid machining as I want it to be a relatively simple and solid build - basically trying to get the best bang for my buck. Either is a straight fit, just a matter of barrels and pistons (2056) plus a crank for 2257. As the 2.0 crank I have has some scuffs and marks on it (which I found last night) I'm going to need the journals polishing (possibly grinding) so there's not a huge overall cost in jumping to the larger capacity

I was kind of on the fence as I don't want it to be a totally lairy car, but at the same time Amie has some (incorrect) preconceptions regards the performance of a 356 I also don't want it to be hard work to drive as I expect this will be used more as a fast road / cruiser than a maximum attack b-road or track weapon. While Stuarts smaller/more peaky engine sounds great (and is probably what I'd build for me) I'm leaning towards the larger capacity for a couple of reasons..

Slightly lazier / more long legged power delivery - with the EFI I can kind of tune it how I want, but cam selection will be key! Sounds like something around the 86b would give a nice top end but still plenty of low down torque

The temptation with the 2056 would be to extract more power from it through head work, additional mods to the top end, etc., which is where the cost vs. return gets a bit out of shape

appreciate any other thoughts / opinions on the above (and below) - I think my spec is looking like..

2257cc (96 x 78mm), balanced and weight matched everything
Web 86b or similar cam
Tidied-up / cc'd heads - not sure about valve springs, rockers, etc at this stage
Weber type throttle bodies, crank fire, Megasquirt EFI

[Bruce M]

Worth noting the fancy 2.0 914 heads have larger chambers so tricky to get a decent compression ratio on a 2056. However if you have the "normal" sized chambers it's less of an issue.

[smallspeed]

I have "bus" heads so less of an issue but thanks for pointing it out - one thing I have considered is 914 heads but they're pretty speedy so I have been looking at the option of relocating the plugs in my existing heads, a-la Porsche.. supposed to give good gains but can't find much info on it and thinking it's the wrong side of cost vs return line for me..

[Splitty64]

Using an 86b, plus with stock gear ratio's you may find yourself dropping gear on big hills, the 86b wants to be at more than 3000 rpm to be in its comfort zone. just be careful to work out your revs vs rear driving scenarios. I dropped cam for exactly that reason, and with an 86 I have 100 lb/ft of torque at just 1200 rpm, which makes for easier driving, plus makes the engine pick up well from very low revs. Just saying work it out, as I said above, I'm about to build another lump using an 86b, with the expectation of it being "driven"

If you are ever in Buckinghamshire, would be happy to take you out so you get a good idea of what it can be like. As for a recomendation for head / other build work talk to Alan at GAC, I use him for my machining and there is nothing he doesn't know about aircooled's

[smallspeed]

Awesome, thanks for the info

[Bruce M]

I have "bus" heads so less of an issue but thanks for pointing it out - one thing I have considered is 914 heads but they're pretty speedy so I have been looking at the option of relocating the plugs in my existing heads, a-la Porsche.. supposed to give good gains but can't find much info on it and thinking it's the wrong side of cost vs return line for me..

There are tales of new Porsche 2.0 style heads being available. I read that a small batch were made to trial but no more as yet.

As per https://aapistons.com/collections/bare- ... round-port

[camperco]

We are using those on our next 914 project. Call for a chat & more details.

[smallspeed]

I spoke with the guys at stateside tuning this morning and he suggested a higher power (vs 2056) and simpler build (vs 2276) would be a 2150cc..
Basic spec:

96mm keith black barrels and flat top pistons (effectively a 2056 barrel/piston kit)
74mm dpr crank
stock length 5.100" con rods - they recommended H Beams but said the stock ones would fit they're just a bit heavy. Given this isn't going to be a rev-monster, I might stick with stock but end-to-end weight matched, new bearings, etc., etc.
web cam - I'm thinking a slightly lower end bias cam as suggested by mr splitty (also by statesite) might be a good idea (2000-5500 range) to keep it moving on hills and things

Note for other people: He mentioned they now have new 914 heads available which they're buying bare, fitting with 44x38 valves, uprated seats, uprated valve guides, ported, polished, etc., etc.. they're £1399+vat per pair which actually sounds like a decent price to me given the amount of work they're putting into them. I think they might be a bit OTT for my build - with lower-end / mid-range power and drivability being the aim, the slightly smaller valves (39x34) and the already fairly decent ports of the AMC heads might be fine (possibly even better to keep inlet velocities up)

I'm convinced with the above thread plus some other chats I've had with other people that a stock 2.0 COULD do, a 2056, a 2150, or a 2276 would all be capable of achieving what I'm trying to do (2276 being overkill for initial goals)

Next step for me before I make any final decisions -

Get the crank assessed and get a price for grinding it. I've had a lot of grinding work done over the years for not much money by a local grinding specialist company, so if the crank is "grindable" within specs, I will prob go that route and build a 2056cc. If the crank is no good, I will go for a 2150cc build for the balance of simplicity and power-upgrade over stock

I think 2276 could be a bit more of a ball ache to build from what I've been told this morning, as it sounds like you need longer than stock rods, which leaves you with a rather funky piston/ring arrangement in order to move the gudgeon pin enough to accommodate the longer rods. The top of the gudgeon pin is effectively getting into the bottom ring area. I'm also seeing these engines starting around 145-150bhp, which would be a peak BHP i'd want for this car so probably overkill, and would be strangled without also upgrading the heads

as always, thank you guys for the input, hopefully some of the information above which I've discovered is of use for other people too.. I will update on my progress as I move along!