Author Topic: 126 and BHP  (Read 4944 times)

0 Members and 1 Guest are viewing this topic.

smallcox

  • Super Member
  • ***
  • Posts: 432
  • Karma: 4
126 and BHP
« on: October 31, 2010, 10:22:07 PM »
So sitting on the toilet and thinking to myself (can you picture the moment) NO,

BHP and 126 engines, my calculation say it takes a fiat 27cc to make 1 hp :oops:

The modern engine averages 13-15cc to a 1HP, so based on that theres room for improvement [-/

Has anybody rolling road a modified 126 engine and what the best BHP out there. I have herd talk about 70bhp from the racing world but is that fact or quess work. The last rolling road session a had was 24 bhp at the wheels on a normally asperated engine. Is it possible to build a 100 BHP monster with 2 cyclinders.

This is your favourite subject Darrell, and don't tell me about the phantom 135mph 595 because we need fact and Rusty will slam you old boy.

Cheers and off to bed after half a bottle of scotttttttch    Smallcox [-/ [-/ [-/
air cooled, gt15 garret turbo with intercooler, 14x9" wheels with 225/40/14 toyos, front arb and disc brakes

Darrell

  • Super Member
  • ***
  • Posts: 1713
  • Karma: 3
    • facebook profile
Re: 126 and BHP
« Reply #1 on: October 31, 2010, 10:53:17 PM »
 :P I have to chuckle on this one as I've pondered the same thing for years, it's why I have ventured down the route of trying to find the formulas etc etc and research on the net, which the article on the 135mph 695 mysteriously disappeared. I think Rusty also saw it but not sure on that one. I think someone must have found out it was rubbish :P

I have resigned myself to the fact that only small increases are possible as if you take a 650 twin bike engine, it'll produce more horsepower but less torque and we need torque no? But this again is pondering...Of course there must be room for improvement, but no one has ever tested the improvements in stages... and I have broken enough for now in the persuit of speed for now :oops:

I planned to put mine on a rolling road but wife wants conservatory so conservatory has stopped play. Over £90 a run on the local rolling road is spoiling play in a big way!

As for the fabled 70hp 595's etc, I've never seen any proof they ever got that, and have to chuckle at claims of doubleing horsepower as there never does seem to be any proof :oops:
Somehow I dont think the 500 club have anyone with figures to check either so we might be 'pioneers' [-/
Somehow the horsepower figures and sucking one's thumb comes to mind [-/
I take it you not working tomorrow  [-/
'84 aircooled 126 & 500F still in kit form
Not the only African in the village :)

gsxr126

  • Super Member
  • ***
  • Posts: 405
  • Karma: 0
Re: 126 and BHP
« Reply #2 on: October 31, 2010, 11:06:31 PM »
I thought your car was around that mark. :P Theres a bloke in Sydney who claims to have 65BHP in his 650 blocked 795cc engine in a 500. That would have to make it an @ 90FWHP engine. A good engine makes 1FWHP per cube. This one is pushing nearly 2FWHP per cube. Given that i doubt its possible to build a n/a twin cylinder to develop 100BHP using standard castings as it would need to have @ 135FWHP and thats nearly 3HP per cube-F1 territory. Of course anything is possible but i see a lot of custom parts and an expensive exercise for anyone who wants to achieve this.

My philosophy is you either keep it standard or if you want to modify, stick a bike engine in it. Its far more effective everythingwise - power, weight, and costs(in the end). Retro fitted fiat engines are ok but from what i have seen they place too much weight behind the rear axle (sorry Jan). My engine/box/diff setup weighs less than 100kg and i'm currently trying to distribute the weight to all 4 corners of the car as evenly as i can. I'm using simple bathroom scales x 4 placed under each tyre. So far the weights are LHR 157kg, RHR 168, LHF 69, RHF 85. its an ongoing process >:(

Oh and by the way if anyone says that a bike engine doesnt have the required torque to push a 126 i would urge them to sit down with a calculator and compare torque to weight figures to any modern performance car and they will get a shock :D
The Good - White Niki all Std Daily Driver, The Bad - Black Niki GSXR1300 BMW diff & suspension, The Ugly - Red Niki quietly Rusting In Peace

smallcox

  • Super Member
  • ***
  • Posts: 432
  • Karma: 4
Re: 126 and BHP
« Reply #3 on: October 31, 2010, 11:10:32 PM »
No i am not working tomorrow,

My plan is to sort out bearing loads then see if a 3 bearing crank is required for 100bhp. But you are asking is this possible, only if you believe it's so, because you have to move the goal post our your just copying the past.

Smallcox, never set me a challenge ::)
« Last Edit: October 31, 2010, 11:14:53 PM by smallcox »
air cooled, gt15 garret turbo with intercooler, 14x9" wheels with 225/40/14 toyos, front arb and disc brakes

Darrell

  • Super Member
  • ***
  • Posts: 1713
  • Karma: 3
    • facebook profile
Re: 126 and BHP
« Reply #4 on: October 31, 2010, 11:14:48 PM »
3 bearing crank :o

I was thinking along the lines of copying the old boys, then seeing if there are any new ideal to play with [-/

Roller bearings on crank yes?
'84 aircooled 126 & 500F still in kit form
Not the only African in the village :)

Darrell

  • Super Member
  • ***
  • Posts: 1713
  • Karma: 3
    • facebook profile
Re: 126 and BHP
« Reply #5 on: October 31, 2010, 11:17:33 PM »
Thought about a counterbalance shaft?  :oops:
'84 aircooled 126 & 500F still in kit form
Not the only African in the village :)

smallcox

  • Super Member
  • ***
  • Posts: 432
  • Karma: 4
Re: 126 and BHP
« Reply #6 on: October 31, 2010, 11:18:18 PM »
Roller bearing on cranks?

I think for racing maybe but for road use no way my son? to nosiey harsh, just bad news. when did you hear off a car company using roller bearings in there engines
air cooled, gt15 garret turbo with intercooler, 14x9" wheels with 225/40/14 toyos, front arb and disc brakes

Darrell

  • Super Member
  • ***
  • Posts: 1713
  • Karma: 3
    • facebook profile
Re: 126 and BHP
« Reply #7 on: October 31, 2010, 11:22:46 PM »
The old Suzuki GSX1100 had roller bearing cranks.

They developed a reputation of having a virtually indestructable crank. Heads and piston rings would go first :oops:

Used to be a party trick to light one's fag on the pipes at rally's with some guys i knew :oops:

I wasnt thinking cars :oops:

PS I have a Ducati 996 engine in the shed :oops:
'84 aircooled 126 & 500F still in kit form
Not the only African in the village :)

smallcox

  • Super Member
  • ***
  • Posts: 432
  • Karma: 4
Re: 126 and BHP
« Reply #8 on: October 31, 2010, 11:27:06 PM »
Now Gxsr126,
Who said it had to be N/A engine, just is it possible to build a road going 100BHP 126 engine. most modern engines use Turbos/chargers

PS motor bike engines are not reliable in a road car or refined. :o

air cooled, gt15 garret turbo with intercooler, 14x9" wheels with 225/40/14 toyos, front arb and disc brakes

smallcox

  • Super Member
  • ***
  • Posts: 432
  • Karma: 4
Re: 126 and BHP
« Reply #9 on: October 31, 2010, 11:30:08 PM »
Darrell,
 I will light my fag with a lighter thanks :P

It was just an excuse to suck pipe in the old days
air cooled, gt15 garret turbo with intercooler, 14x9" wheels with 225/40/14 toyos, front arb and disc brakes

Rusty's Uncle

  • Subscriber VIP+
  • Super Member
  • *****
  • Posts: 2837
  • Karma: 34
Re: 126 and BHP
« Reply #10 on: November 01, 2010, 06:53:52 PM »
When I bought the 795 ccs engine with the Alquati parts the guy was talking about it making 56 bhp , sounds like a big ask to me but who am I to argue with a man who is a renowned test pilot with a history of tuning & racing classic cars & bikes as a hobby  :oops:

gsxr126

  • Super Member
  • ***
  • Posts: 405
  • Karma: 0
Re: 126 and BHP
« Reply #11 on: November 02, 2010, 12:35:15 AM »
OK Smallcox,

I thought you were talking n/a. Yes i agree, if you go turbo you should be able to achieve 100BHP, but the issue of custom parts required to handle the stress of a turbo still makes it expensive. I would drop the compression to 6:1 put a monster turbo on it and run it at around 40psi. I've done this with a suzuki 1.3 engine but reliabilty becomes a big issue.

What makes you say that bike engines are not reliable :o
The Good - White Niki all Std Daily Driver, The Bad - Black Niki GSXR1300 BMW diff & suspension, The Ugly - Red Niki quietly Rusting In Peace

gsxr126

  • Super Member
  • ***
  • Posts: 405
  • Karma: 0
Re: 126 and BHP
« Reply #12 on: November 02, 2010, 08:21:22 AM »
Hey Darrell,

996 Ducati :P i think they made about 135bhp and 105nm.

Here's some quik comparisons for you:

480kg(being the ideal weight to get a 126 down to)/135bhp=3.55kgs per bhp
480kg/105nm= 4.57kg per nm.

Compare that to a HSV W427 (the most powerful street car produced in Oz) with figures of 503bhp,613nm & 1874kg
and you get 3.72kgs per bhp & 3.05kg per nm.

I have to admit that the nm figure is down a bit but remember this a 427cid V8 motor in one of the latest cars capable of doing 11s in the quarter. And its being compared to a Ducati motor. I dearly wanted to put a Duke in the niki to keep it all italian (being one myself) but they just werent powerful enough for me. My suzuki 1300 gsxr engine puts out 240bhp and 191nm (do the math). I'm aiming for 10s quarters [-/
The Good - White Niki all Std Daily Driver, The Bad - Black Niki GSXR1300 BMW diff & suspension, The Ugly - Red Niki quietly Rusting In Peace

smallcox

  • Super Member
  • ***
  • Posts: 432
  • Karma: 4
Re: 126 and BHP
« Reply #13 on: November 02, 2010, 10:04:25 AM »
Let me think, I beleive a bike engine is reliable when fitted to a bike but...... When a heavier vehicle is used their reliablity drops but i quess 80% of this is down to how well they are fitted like all things. Also if you use the car often bike engines are harsh but great fun after all grass track racing see many bike engines sitting in the rear seats powering cars round all season.

I don't believe it's possible to build 100hp to use all that power all the time because off block flexing issues and the cyclinder head ability to flow well, but the modern road car say impressa turbo 230hp from 2 litre with a warrenty so 700cc equals 80hp we are talking engine bhp here,but the impressa can be modded to well the sky but say 300hp then that takes 700cc to 105bhp. Now mitsubishi don't they do a 400hp 2 litre with a warrenty.

so as mentioned on the 1st post a modied 650 engine with 15cc per hp = 43.3hp

So i ask is it possible with all the draw backs off the 2 cyclinder engine is it possible to build a 100 bhp engine that is road usable?

Smallcox :-
« Last Edit: November 02, 2010, 10:15:49 AM by smallcox »
air cooled, gt15 garret turbo with intercooler, 14x9" wheels with 225/40/14 toyos, front arb and disc brakes

GTMaster

  • Super Member
  • ***
  • Posts: 809
  • Karma: 2
  • Na most a tuti- tuti- tuti
Re: 126 and BHP
« Reply #14 on: November 02, 2010, 04:30:01 PM »
I'd say it would be possible, just that  i reckon it would vibrate a lot (vibrates quite a bit with just 24hp)....
"One more drink, Lacikám?"

All about car restoration can be found in the song
"Got my mind set on you" by George Harrison...

 

SimplePortal 2.3.6 © 2008-2014, SimplePortal