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having issues with older V8s
Posted:
Thu May 21, 2015 12:57 pmby RioRedSVT
i wanted to make a car from each decade starting with 1940. i am having trouble making a decent V8. or any motor for that fact. after 3 hours of trial and error the best i got was 208hp@4300RPM. i want more RPM and better life, most of the parts turned yellow if not full red at 4500RPM. is there a link to engine building video on youtube? (not the monster motors, just a good powered daily driver) my main problem is the valve float. any help is much appreciated.
Re: having issues with older V8s
Posted:
Thu May 21, 2015 1:16 pmby RioRedSVT
so i just tried my hand at a modern motor, did a 281C.I. 4v V8 got 490hp@7800RPM. so is it just not able to make higher powered motors in the 40s and 50s?
Re: having issues with older V8s
Posted:
Thu May 21, 2015 2:40 pmby Slim Jim
Yup, sounds about right. The game is designed to simulate the progression of technology over time. Late 30s, early 40s, the most powerful road car was the Duesenberg. 8 cylinders, naturally-aspirated, 265 horsepower. Since that's gross horsepower, figure around 210 using today's standards. That was the pinnacle of performance back then. Supercharged Duesys made between 320-400 horsepower gross (260-330hp today) but we don't have superchargers yet.
Re: having issues with older V8s
Posted:
Thu May 21, 2015 4:16 pmby RioRedSVT
And the revs? i cant seem to find any way to get them over 4500 or so without the Valve Float break down...
And Thank you for clearing that up for me.
Re: having issues with older V8s
Posted:
Thu May 21, 2015 4:26 pmby oppositelock
RioRedSVT wrote:And the revs? i cant seem to find any way to get them over 4500 or so without the Valve Float break down...
Better valvetrain (i.e. 4 valve DOHC)
Higher top end quality
Smaller bore
Bigger cam
You're really not going to get a lot of revs in 1940 unless it's a really tiny engine, though.
Re: having issues with older V8s
Posted:
Sat May 23, 2015 3:57 amby Dolehof
Making strong V8's in the 40's isn't that difficult, the problem I have is that it usually doesn't have much purpose as the wheels aren't able to transfer all that power to the road in that era, so going above 250 hp doesn't add much in actual performance of the car.
As a hint, keep your cam profile low, since you want power at a low rpm. Then slowly increase to compensate for valve float and octane levels.
Re: having issues with older V8s
Posted:
Sat May 23, 2015 4:07 amby nialloftara
As a benchmark the Oldsmobile rocket 88 was pretty quick for 1949, and it could do 0-60 in about 13 seconds.
Re: having issues with older V8s
Posted:
Sun May 24, 2015 9:51 amby Lordred
RioRedSVT wrote:i wanted to make a car from each decade starting with 1940. i am having trouble making a decent V8. or any motor for that fact. after 3 hours of trial and error the best i got was 208hp@4300RPM. i want more RPM and better life, most of the parts turned yellow if not full red at 4500RPM. is there a link to engine building video on youtube? (not the monster motors, just a good powered daily driver) my main problem is the valve float. any help is much appreciated.
Here is a quick 283cid 221hp SOHC 2v motor I slapped together, it is a large bore / short stroke combo engine. Valvetrain is at +15.
However if you desire to use only a quality of 0 for your sliders, then you will have to work in the lower RPM range.
Re: having issues with older V8s
Posted:
Sun May 24, 2015 10:50 amby nialloftara
You just didn't rev that high back then, here the wiki from the engine of the 125s, the first Ferrari build back in 1947
"The 125 S was powered by Gioacchino Colombo's 1.5 L (1497 cc/91 in³) 60° V12 with a bore/stroke of 55 x 52.5 mm . This engine produced 118 bhp (87 kW) at 6,800 rpm with a compression ratio of 9.5:1. It was a single overhead camshaft design with 2 valves per cylinder and three double-choke Weber 30DCF carburettors."