Getting power from a 172 / 182.

[HrRACING]

Having a lot of experience trying to extract power from the K4M 1.6, which has been less than easy, what are the 182 / 172 engines like to tune.

Is it considerable easier? Lots of off the shelf parts available?

What sort of reasonable power can you expect from one with throttle bodies, proper exhaust manifold, headwork, proper cams, solid lifters, forged bottom end etc.

Any info would be greatly appreciated!

Many thanks
Hal

 

[Chip-mk1]

I'd say that relevative to most of the common compeition engines they are pretty piss poor to tune TBH

But even with that said if you go as far a solid lifters and uprated rockers so you can actually rev the thing properly 250bhp+ certainly wont be a problem although valve area will need increasing to get you into that region.

You are always going to suffer though because the piston speeds will get ridiculous if you start trying to turn 10Krpm+, largely due to the crank throw being so long, but then exaggerated still further by the conrods being so short.
Ie its got a really bad bore/stroke ratio and also a really bad rod ratio as well.

 

[marinemackay2003]

from here http://www.cliosport.net/forum/showthread.php?596482-F4R-Engine-Building

Stage 1 Performance: Customer Supplied Core Engine

• Engine stripped to component form, cleaned, measured, checked.
• ACL big end bearings, OE Mains and Thrust
• New Seals and Gaskets throughout.
• Track-Group Steel Rods with ARP Rod Bolts
• 12:1 CR Forged Pistons with option of DLC skirts.
• Track-Group oil pump assembly.
• Block honed
• New valve guides
• Valve seats recut
• New camblet and tensioners
• New Lifters and rollers
• Track-Group cylinder head porting.
• CAT421 Cams

This spec is good for around 225bhp with a sustained 7800RPM rev limit. £3800 + VAT

Both of these are supplied with 12 months warranty as long as you don't over rev them, over heat them or run them out of oil.

Beyond that it gets into our motorsport stuff - Super Production/Super 2000 which offer 240bhp/280bhp respectively but are a bit pricey!



but like what chip has said solid lifters and better rockers ect more power can be done £££££ though

some have achived 230 odd from itb's cams, head work and forged pistons

 

[HrRACING]

That does sound good.

Interested in the Motorsport stuff. I have been doing Super1600 Rallycross for a little while now using a K4M but looking for a change in direction.

Tell more. Would be great if you could post it in this thread then I could put it all in one place.

Cheers

 

[Chip-mk1]

Your best bet is to contact TDF in my opinion, they've got a lot of experience with these engines in motorsport at higher levels than most other people who are involved with them.

But obviously be prepared for a bill that is WELL into 5 figures.

 

[marinemackay2003]

from here http://www.cliosport.net/forum/show...PM-From-an-F4R-Engine&highlight=solid+lifters

from matt @ TDF

You don't need solid lifters for 8200RPM but what you do need is sensible life on the roller rockers. They don't last long above 8000RPM and 8500RPM is the absolute limit for them. We have uprated ones with a DLC coating that last longer but still only rated for 1000KMs of race use in the S2000 engines.

7800RPM can be done on stock stuff, 8250RPM requires stiffer valve springs and good quality new lifters. Be aware that by increasing the valve spring stiffness you are also increasing the load on the cam drive and as such should investigate if the clamping load on the cam and crank pulleys to ensure they are sufficent to retain positive location as well as what second and fourth order vibrations are present. You will want to keyway both the crank and cam pulleys for sustained used above 8000RPM.

The entire bottom end rotating assembly needs to be balanced to a sensible tolerance (note not crazy money heavy metal weighting type stuff just sensible), the stock crank is fine to 8500RPM but we do a steel one should you feel the need to be £2200 poorer. We also do an uprated steel rotor for the stock oil pump assembly which is safe to S2000 rev limits but you're probably fine on an OEM spec pump to a transient 8200RPM.

PM me for prices but not cheap. IIRC the rockers come in at over a grand, DLC coating alone is £350 as essentially they're 32 bits not 16 as the roller and arm require seperate coating operations. Do you really need another 200RPM that much?


as chip has said Matt is the man to speak to

http://www.tour-de-force.co.uk/

 

[MartinR]

^^Alot of money for so little gain

 

[Dan519]

Above is a very odd cam choice for high compression. big retriction at that point

 

[marinemackay2003]

yeah i thought so too as if going forged ect, most go for 422 or 423's

but im no expert and im sure that Matt has selected them for a reason

 

[elandman]

Having a lot of experience trying to extract power from the K4M 1.6, which has been less than easy, what are the 182 / 172 engines like to tune.

Is it considerable easier? Lots of off the shelf parts available?

What sort of reasonable power can you expect from one with throttle bodies, proper exhaust manifold, headwork, proper cams, solid lifters, forged bottom end etc.

Any info would be greatly appreciated!

Many thanks
Hal

Sorry this is a bit off topic here.... but what are you managing on average to push from a K4M?
Thanks

 

[Dan519]

yeah i thought so too as if going forged ect, most go for 422 or 423's

but im no expert and im sure that Matt has selected them for a reason

well I can tell you from experience that 421s are best for standard compression, but not otherwise. I've dyno'd 2 cars with near identical spec apart from one being high comp (so both on 421s) and the high comp car made 4bhp more. changed to 422s roughly another 20bhp was freed up.

there's a slight downside that the torque band is pushed up the rev range, but I would say stick with stock compression if this is an issue. There's no point bumping the compression up if you don't use the appropriate cams to take advantage if it.

 

[HrRACING]

Sorry this is a bit off topic here.... but what are you managing on average to push from a K4M?
Thanks

Power wise, 190bhp now with a bit more to come.

Thanks for all your responses folks, very interesting.

 

[elandman]

Power wise, 190bhp now with a bit more to come.

Thanks for all your responses folks, very interesting.

Thanks