"This is the Nissan Primera GT, as raced in the 1999 British Touring Car Championship (BTCC). The Primera is powered a 4 cylinder 16 valves 2 litre engine that produces over 300 bhp @ 8300 rpm."
And if anyone mentions 1916cc's I will delete the comment... Straight away :P
I don't think variable timing would work. They remove them on race cars anyway, too much reciprocating weight. Plus you gear your car for a specific powerbands. I think light valve train is the go. I know V8 supercars are pushrod operated, no ideas what the specifics are tho. But they pump out over 620BHP.
Ceramic internals... What do you mean by that? I know you can get ceramic valve gear, but never heard of ceramic internals before.
Just munching it over casually, 150 bhp per litre is quite high, and probably beyond what could remotely be called "streetable" .
Some streetable bikes produce specific power outputs of this order, but the power/weight ratio of these bikes is such that "streetable" ceases to be an issue; what I mean is when you have over 150 bhp for only half a tonne of bike, you'll find a way to get it through the traffic without stalling; this means that cam profiles can be quite radical.
To get into the range of 150 bhp/litre on pump petrol (not specified, but a major limitation assumed), normally aspirated, the engine would need every advantage known to engine building; the best n.a. Chev 383's don't come near 940 bhp on pump fuel, largely because of the valve train.
The engine would need to be water-cooled (air-cooled might do for dragging, not for continuous output in this range), have overhead valve gear and multi-valve heads; it wouldn't really resemble a Type 1 engine.
The other critical element right from the outset is the combination of bore/stroke ratio and con-rod angle; I think you'll find that you'd be having a careful look at why certain Type 1 engines of around the 1.916 litre capacity (not to put too fine a point on it) deliver very good horsepower, considering their otherwise antiquated design (valves and valve actuation).
Overall, I can't imagine why anyone would bother, or alternately, having bothered and achieved something like 150 bhp/litre, what would have been proven. Still, fills in an evening.
Thats turboed dude 😉 Love that car though. Going to see it in the flesh in a couple of months. :bounce
It can be done, I'm sure it can. Pneumatic valves would be a must have! And fully custom built light weight valve gear too. As I said... V8 supercars can get 620+ on shell optimax, so it must be reachable. There are big cc Type 1's in the US running on pump gas with 250.
BTW, this would be a race only engine too guys 🙂
Cam wrote:... V8 supercars can get 620+ on shell optimax, so it must be reachable.
Errr...that's about 108 bhp/litre.....
Cam wrote:there are big cc Type 1's in the US running on pump gas with 250.
I thought by "the same hp" you were implying in some way comparable with the Nissan 2 litre... there are 600 c.i. engines also turning out big numbers, but not 150 bhp/litre....
No reason. Just thought it would be a good thing to think about. However I do like the responsive nature of NA engines over artificial. But thats a whole other argument that we won't get into. I do however know that WRC cars are limited to 300 BHP so use the turbo's to get as much torque as possible over 600NM's. Which is a turbo motor I like the sound of 😀
Errr...that's about 108 bhp/litre.....
I thought by "the same hp" you were implying in some way comparable with the Nissan 2 litre... there are 600 c.i. engines also turning out big numbers, but not 150 bhp/litre....
Yes, yes, I was. Just thought it would be an interesting topic of conversation.
I know a guy in Sweden who put 911 heads on a type 1 motor about 30 years ago, stainless steel plates either side of the magnesium case with big through bolts. This would be a must do head conversion for a big HP AC motor. twin plugs, OHC's, better cooling, etc...
As I said, just interested to know what you guys think and how you personally would attack the task.
cam about 5 years ago my uncle had a moto in his race buggie that was good for about 200 it was a type 1 engine it was werth a mint and it was fast it won its class the fist race and blew up ever race after that it was n/a but i imagen tecnoligy has gone a long way in 5 years and he now runs a nissen motor in near standed trim with tons of boost and its so much more reliable and is it fast
i thirt of some thing funny and stupid to write here then i forgot it
i agree that the 911 head conversion is definately a good step forward, that's why i like russ's bug so much, the turbo just gives it that extra bit....
there was a bug a few years back that competed in autocross in the uk, i can't remember if it was t1 or t4 based, but it had subaru quad cam heads (the heads were water cooled, the rest of the motor was still air cooled....and a turbo too
this thing pumped out around 500bhp i think!:P
Yep, I know the one you mean, Kai. Belong to Pete (surname escapes me). He passed away a couple of years ago. Apparently his brother has the car and has put the word out that it is for sale.
Travis, yeah man. You said you had a stack on the phone. Thats shit man. I'll give you a call on tues or something. Or give me a call on the weekend if you want to catch up.
Comparing apples with apples, a 2 litre Kombi motor puts out about 60-70 hp, a 2 litre Volvo motor (still with pushrods) puts out around 120, it must be in the heads, cam etc.
On the other hand no one can get near Gummleys supercharged type 4 powered hillclimb car, even when using twin cams, 16 valves, turbos etc.
Last Sunday , I spoke to the guy that did heads on Gummleys ...
I'll be sitting with him on Sat at Drags.
He told me some techniques but best to ask him
yourself, introduce yourself at drags.
Cam wrote:However I do like the responsive nature of NA engines over artificial.
I thought some super chargers has power-on-tap, unlike turbos with their infamous lag.
There was an interesting article in a recent Motor magazine comparing a commodore and falcon, both with s/c. Different types though. The commodore had grunt from go to whoa! While the falcon had it from about 2500-3000rpm.
VW car, VW engine ...... keepin it "real"
35MPG on 101.3kPa
Craig Torrens6 times Australian, 7 times State Hillclimb Class Champion
Superchargers are parasitic, they suck HP to make more, turbos if sized properly dont display the lag of days gone by, 300 hp out of a T1 is definitely possible, then just turn down the boost for the street.
150 BHP/Litre is well exceeded by most large production sports bikes now. However, this is done with obscene RPM's Always in excess of 10,000rpm.
Crikey that would be one bit of work to get a kraut to rev like that...at least once anyway!!
A way of attacking this would be to look closely at adapting the heads off something like a big inch Ducati or similar twin which will have the potential to flow that much quite easily but to get the rest of a 'dub boxer engine to stay together at the revs demanded may well be an exercise in futility!!
Bwaaahahahah imagine that ratty old beetle whizzing away down the road at 12,000rpm!!!!!!!!
Im not a complete idiot, quite a few parts are missing....
Craig Torrens6 times Australian, 7 times State Hillclimb Class Champion
use the new aluminum cases.............................destroke the crank like Ducati has done.............................maybe a turbo (although we want normally aspirated!)............mmmmmmmmm imagine a 10000rpm beetle:thumb
vw flat 4 motors will never be high revving motors!!!! apart from very occasional crazy drag race combos, like 1584cc 13 sec. (i think) drag car in the u.k a few years back, that revved to 9 grand!!!! 48 ida's on a 1600.....
that's why i reckon a turbo is the way forward, you can set it up so that full boost arrives nice and early in the rev range, maybe 5000-6000rpm.... that way ya don't have to screw the nuts off it for the power.
then there's always the NOS bottle..... and water injection..... there's tonnes of stuff you could do.
