Today I finally got my banger on the rolling road. I've been wanting to this for a long time as its the only way to know what power your really making and what areas need improving. The other reason was that I plan on pulling the engine soon for more work, so I wanted to know what the power output was in its current spec. Current Engine spec is as follows, Block. Diamond 'B', 'C' crank, full pressure with inserts. Head. Lion Head II, 7:1 comp. Cam. Dan Price grind. Specific specs unknown. Valves. Completely stock, even down to the split cast iron guides. Ignition. Scintilla Vertex magneto, 8 degrees advance @ 1840 rpm. Timed by trial and error, never seen a timing light! I estimate its about 8 degrees before top dead. Intake. Dual 97's. Again set-up by trial and error. 43/44 (45 stock) mains and #72 power valve (#65 stock, #72 stock for an 81). Exhaust. Dan Price 4 into 1 header through a 2" system with a smitty. 1st Pull. This was the first pull on the dyno. Spec as above but with stock 45 main jets put back in the carbs. This was due to me not knowing wether I was coming or going with the main jets, so putting them back to stock was a good starting point. I was aiming for 80 bhp at the wheels. I got.... 84 bhp at the wheels! Running well but the gas ****yser was indicating a very weak mixture. Dual 97's on a banger and its running lean! I should have had a of mimimum 5% carbon reading, I had 0.5-1%! 2nd Pull. First job was to jet the carbs up. The biggest I had on me was 47's from my single carb days. Back running again we got 5% carbon on the gas ****yser, spot on. 94 bhp at the wheels, a 10 bhp increase! Its going well. 3rd Pull. The third pull was to adjust the timing. The current mag position was marked as a starting point and at wide open throttle pulls the mag was turned either way. In the end it only ended up be advanced by 1-2 degrees from my position. Not bad for trial and error! 4th Pull This was the final going for broke pull. Jack-pot! 100bhp at the wheels at a miserable 3000 rpm! Summing up. I ended up with a 15 bhp increase, its more smoother on the top end of the rev range and it has a real kick to it now when you change gear. I think I've proved that 97's DO work on a banger, they just need setting up properly. Even the guy on the rolling road that has been doing it for over 30 years was impressed with the acceleration when you floored it from a cruising speed. I so want to give it ago on the strip, but it seems un-likely it will happen again in its current spec.
Excellent Clark! You do it - I'll just read about it... So "not in it's current spec" eh? What devious plans lay ahead? Out of interest, what size horses do they have at that rolling road? The one I used to go to had ponies - the numbers were a little larger than elsewhere!
Good stuff!! That's real world info that I like to see. 100 ponies to the pavement should churn 'em and burn 'em. Thanks for sharing that; we (bangerheads) need more.
Forgot some info. It has a 60 thou overbore. 1/4 mile times were a consistant 18.8 @ 70 mph before the rolling road session.
Phil , the reason that happens is down to either ; a) a poorly serviced / calibrated dynomometer roller b) an older dyno with no automatic in-built weather station c) an operator feeling sorry for you gasping old wreck by fiddling the atmospherics settings We all know how air temperature and pressure have an effect on the way an engine performs , and a dyno runs software to let you compensate for different atmospherics . Fiddle these and the power goes up . Not that I ever did anything like that of course , especially not after selling and fitting £1000 worth of so called performance exhaust to a customers' bike , no no no . Sorry if I'm teaching anyone to **** eggs , but its not often I get a chance to show off any technical knowledge and I'm enjoying myself
Great job and congratulations. If you don't mind me asking, about how much you got in to that little banger?
That's awesome, and somthing to aspire to! It's good to see some figures! Outback Don't want to get OT but what power are others putting out in their bangers?? I chucked mine on at a recent show, and got 27.8hp it was overfueling the air fuel ratio fell off the bottom of the graph.....
Like I said it's a little rich, I don't get time to drive it very often, so every chance I get I jump in the saddle and drive the wheels off it, time tinkering is less seat time. Next hols though will be a bit of work, got a F100 column to stick in it, and hopefully a head to chuck on, may even slip the cam in too Oh Yeah, tune the carbs, and sort the ign out! OB
Very cool.............but, shhhh. Banger's will be the next flatheads for the "Hotrod" trend. Chris Nelson Kansas Oh yea, were did you get the Lion head? Was it the guy in Hemmings?
I think the cost of producing decent power from a banger will keep the scenesters away. These things soak up money like a sponge.
That's true, funny, and sad. I should have charged the last guy that gave me a block . I think he just wanted to slow down the progress on the V4-HA/GR.
what gears are in your ******, what rear ratio and what tire size are you running? also what is the body? coupe? do you know the total weight of the car? just wondering and thinking about my banger project thanks alot zach
This is the car.... Weight is around 2257 lbs. Rear end is I ***ume 3.78:1 as its stock. Tyre size is 4.75 19 about 29 inches overall and finally gearbox is stock 3 speed with 1st and 2nd close ratio, 3rd is stock at 1:1. What are you trying to work out Zach? Peanut, I'm mainly having the valves done next.
well.....i have big plans to build an early to mid 30's era correct 29 roadster that will do over 100mph on the highway stock frame, stock body, pretty much look like a stock A roadster with 17 or 18 inch wheels no fenders and a full hood but with a mean growl and plenty of gow! stock mechanical brakes. basically what someone in that time would have built. paint the body really nice with factory pinstriping and everything its probably more of a dream then anything right now but if all works out i might have the money for it by next fall im just trying to figure out what parts and what not other people are running to decide on what i want to hunt down i have this graham centrifugal supercharger i think its a 36 but im not sure i want to run that with the mechanical brakes as the lag getting off the throttle and the lack of good brakes at 100 might get a bit hairy its just a dream right now thanks alot for the info zach
I totally understand where your coming from. Heres a Tom Fritz painting lifted from hopupmag.com. Look closely and check out the details! Nothing wrong with mechanicals. I found that biggest limiting factor was the tyres not the brakes. This is what I have in mind for mine eventually.
very bueno...now loose the smithy and you will probably pick up 2 - 5 more horses (those things have to be power hogs)
thats a coupe with the roof cut off! do you think those 32 brakes would be better then the A's? what did they do to make the mechanical brakes work with the dropped axle? ...just make extensions? i have a full set of 32 brakes, axle and spindles maybe thats the way i should go? i think these types of cars are for your own pleasure almost no one understands the desire to have mechanical brakes and things like that to me...its a time machine...i want to view the world through the eyes of whatever year i desire cars are my means of doing so as thats where my interest lies so if i build a car based in 1949....everywhere i look on that car i want it to be 1949...if i build it 1935 then thats what its going to be unfortunately on my first car i cut alot of corners in an effort to get it done but i learned my lesson as im not happy with it so i will change it and then do another...and another...and...well i'm gona have quite a few 29 roadster i think zach
I believe the '32 mechanical brakes are better due them being 12 inches in diameter compared to the Model A's 11 inches.That makes them the same size as hydraulics but they are not as wide. '35 and on mechanical brakes are the same as hydraulics. Also I think the '32-'34 brakes will bolt straight on, un-like the later mechanicals and hydraulics. I know Jim Brierley (4 port Riley) has done the conversion so he's the man to talk to.
The Jalopy Journal
