2.1 Pinto

[DarthVader]

[escortinadriver]

Very good going.
What are the head specs?

Shaun

[Group4_Mark2]

Nice power curve and at low revs as well so it will not stress the engine so much. Should be really good to drive. Have you tried to tune out the dip in the torque curve at 4000rpm?


Tom

[Arieke]

212 BHP verry nice, wanne see something like that on my engine.

[DarthVader]

We've currently got a set of 42mm chokes fitted , would like to try a set of 41mm but are struggling to find. Motor is also running with standard EFI dizzy (non vacuum) dizzy so there is room for improvement.

Racing again next week and after that I think the new 2.3 sub will be built.

[RWD fords rule]

In english money that's 209.3 bhp and 178.5 lb/ft
Good figures, what is the cylinderhead spec?

Valve sizes, 48's or 50's? or is it all top secret :D

Jason

[DarthVader]

44mm inlets, standard size exhaust valves. Intake valve with wasted stems - Ford valves replaces with Mazda B6 valves to aid rocker ratio
Head - standard exhaust ports, intake ports lifted 5mm, skimmed for CR of 13:1
48 DCOE's
Toyota 22R pistons - 92.5mm pistons skimmed till 0.5mm proud of block
Isuzu petrol conrods
102 Octain fuel
Kent GTS7 cam

[RWD fords rule]

44mm inlets, standard size exhaust valves. Intake valve with wasted stems - Ford valves replaces with Mazda B6 valves to aid rocker ratio
Head - standard exhaust ports, intake ports lifted 5mm, skimmed for CR of 13:1
48 DCOE's
Toyota 22R pistons - 92.5mm pistons skimmed till 0.5mm proud of block
Isuzu petrol conrods
102 Octain fuel
Kent GTS7 cam

209bhp with 44mm inlets and 36mm exhaust valves, no ofense but I think your power figures are more than a little optimistic or there are better parts in there.

Std exhaust ports will never make 209bhp N/A form unless your running on a sh1t load of nos.

Anyway all I am saying is that spec does not add up to 200bhp let alone 209.

Regards
Jason

[DarthVader]

No offense taken RWD. Car was dyno'd again last week on brand new dyno that was installed at the track a month ago. Power was up 2HP.

I'm sworn to secrecy about the tricks performed on the head. But I supose I can show u what a volvo head looks like:thinking:







Think out the box

[RWD fords rule]

Hi there

That is a very nice looking head, I definatley remember seeing those photo's before.

What type of welding did they use arc or mig and what type of rod?

Looks like a good job, massive improvemet on a std head lol.:thumb:

[DarthVader]

I'm not sure RWD, I think sleaves where press fit.

[RWD fords rule]

I'm not sure RWD, I think sleaves where press fit.

No that has definately been welded.

[DarthVader]

I ment the way it was done on our pinto head. Looks like the volvo head has had plugs fitted into ports and then the ports re-machined

[Lilljebjorn]

Some engine builders here in sweden use 44mm inlets and 37 exhaust valves with very good results...

[escortinadriver]

Can we get a look at the down draught pinto head???:pray::pray::pray: I have plenty of pics of Volvo heads but I lost my only pinto ones years back when the computer crashed...

Thanks, Shaun

[DarthVader]

I will see what I can do, unfortunatly head is fitted so will have to wait till the carbs or head comes off.

[escortinadriver]

Thanks for that. :clap::clap::clap:

It would be very, very appreciated....:thumb:

If you do manage to get a few shots of the head can we get a few different angles, ie down the throat, from the front/rear etc.... Pics with the carbs attached and of the custom? inlet manifold would also help.

Many thanks in advance,

Shaun

[Group4_Mark2]

I have a few photos of a downdraught head











Engine is from a company in Sweden called jpmotorsport.se

Produces 250bhp using bike race carbs. He is using titanium 46.5mm inlets and I think 37mm exhaust valves

Price is €4000 - €4500 for a complete downdraft head
Price for head plus manifold plus slide throttle racing bike carbs is €7000


Tom

[Arieke]

I have a few photos of a downdraught head

pics


Engine is from a company in Sweden called jpmotorsport.se

Produces 250bhp using bike race carbs. He is using titanium 46.5mm inlets and I think 37mm exhaust valves

Price is €4000 - €4500 for a complete downdraft head
Price for head plus manifold plus slide throttle racing bike carbs is €7000


Tom

Thats alot, but looks nice :lol:

[DarthVader]

WOW - thats what we got ! Shows u,think u onto something new and it's been done already!

Are those flat slide carbs ?

[Graham]

Are those flat slide carbs

looks like it

the bike world has by and large moved away from them many years ago, using bigger cv carbs they could match the power of flatslides but with much better ecomony and emissions

[Group4_Mark2]

I spoke to the guy and he said they were slide throttle carbs off some sort of racing bike. He was charging a lot of money for the carbs and manifold approx €2500. The modified head was €4000

[DarthVader]

Now that the cats out the bag.....

Our first head we had made has less of angle on the intake ports, so with and adapter between a standard dcoe we could get the angle to within the 7Deg from horizontal that a dcoe can operate in. This head had brass inserts, forgetting about the different expansion rates we had some problems with leaks, block leak cured this and never had issues again

The new head has probably more angle than the head from JRE, we where contemplating Hilborn mechanical fuel injection (class rules don't allow EFIi) I forgot about bike carbs, so some searching will be needed to see if I can find something like the JRE carbs. We have now changed to cast iron inserts so hopefully this will cure the leak problems.

Our new race pinto will have the above mentioned head, 95mm wiseco pistons with a compression height of 25.5mm, stroker crank, BMW conrods +- 2.3L. Head will have bigger valves. Our aim is 260 / 270Hp and hopefully loads more torque.

[Group4_Mark2]

The guy I spoke to said that the head was very difficult to make, hense the price. I think he may have welded some sort of pipe into the head but I could not be sure of that. He said that this job alone took most of a weeks work. The valves, retainers etc were titanium to reduce weight. He was getting max power at 8000rpm with max rpm 9000rpm plus. Power was supposed to be 250bhp from 2 litres


Tom

[zahistorics]

Craig, hope to WPMC opposition are not reading this.....

[DarthVader]

So then our motor (also 2.0) is'nt to bad - cam being the main problem as can be seen from dynosheet.

ZA- I hope so too.

[RWD fords rule]

Now that the cats out the bag.....

Our first head we had made has less of angle on the intake ports, so with and adapter between a standard dcoe we could get the angle to within the 7Deg from horizontal that a dcoe can operate in. This head had brass inserts, forgetting about the different expansion rates we had some problems with leaks, block leak cured this and never had issues again

The new head has probably more angle than the head from JRE, we where contemplating Hilborn mechanical fuel injection (class rules don't allow EFIi) I forgot about bike carbs, so some searching will be needed to see if I can find something like the JRE carbs. We have now changed to cast iron inserts so hopefully this will cure the leak problems.

Our new race pinto will have the above mentioned head, 95mm wiseco pistons with a compression height of 25.5mm, stroker crank, BMW conrods +- 2.3L. Head will have bigger valves. Our aim is 260 / 270Hp and hopefully loads more torque.

So much for moving the ports up 7 or 8mm as you first said, wee bit of an understatement there ted.

Are you using nikasil liners to get that bore size?

Regards
Jason

[RWD fords rule]

The guy I spoke to said that the head was very difficult to make, hense the price. I think he may have welded some sort of pipe into the head but I could not be sure of that. He said that this job alone took most of a weeks work. The valves, retainers etc were titanium to reduce weight. He was getting max power at 8000rpm with max rpm 9000rpm plus. Power was supposed to be 250bhp from 2 litres


Tom


I don't understand why he never welded the chambers, surely that mod would have go him a much better burn, slightly more intake flow and the possibility of 13 to 1 comp, all that should have added at least 8bhp if not more.

I have found high quality cast iron mig welding wire, I believe that is the secret to building the downdraft head together with cast sleeves, which I am sure could be sourced.

Regards
Jason

[Graham]

I don't understand why he never welded the chambers surely that mod would have go him a much better burn

im not conviced its worthwhile to weld the chambers unless a radically high c/r is your goal, afterall, a mere 28 degrees of advance has got "linford" which is a true 2.0 making a nats cock off 188bhp

[DarthVader]

Sorry RWD :giveup: - could'nt say much at that stage.

No the linners are normal press-in steel liners.

[RWD fords rule]

im not conviced its worthwhile to weld the chambers unless a radically high c/r is your goal, afterall, a mere 28 degrees of advance has got "linford" which is a true 2.0 making a nats cock off 188bhp

The pinto combustion chamber is still not the optimum shape, welding the side opposite the spark plug will definately add bhp due to a faster fuel burn rate needing less ignition advance, the faster burn will create more pressure on the piston crowns for a given compression ratio and definately give more bhp at high rpm.

The other advantage is that a pinto head with welded chambers would need a lot less skimming to get 12 to 1 and also need shallower valve reliefs.

Regards
Jason

[Graham]

welding the side opposite the spark plug will definately add bhp due to a faster fuel burn rate needing less ignition advance, the faster burn will create more pressure on the piston crowns for a given compression ratio and definately give more bhp at high rpm.

if you were talking about needing 20 degrees less adavnce id agree,

still not sure on that welding would actually give a power increase, especially after talking to dave walker recently about his twin plug pintos, the twin plug head needed only 22 degrees of adavnce v 30 something of the single plug, but the power was absolutely the same though,

you cant get a much worse combustion chamber than an x/flow with a flat head and flat piston running a long way down the bore but powerwise at the topend that combo works as well as anything else

[DarthVader]

To add :
Our current motor made max power/torque @ 28deg with standard head skimmed only. Unfortunatly valve/piston clearance is minimal and playing with cam timming is a no-no.

But we cannot get CR higher with out skimming head and pocketing pistons. Welding headup - not worth the risk in my opinion as as we've had to bin a perfect Efi head after it cracked when welding (arc) Mig might be a option to consider

[DarthVader]

Dave's R1 carbs have got me thinking, would they work at that angle ? Could they flow enought for 270BHP ?

[Group4_Mark2]

I have found high quality cast iron mig welding wire, I believe that is the secret to building the downdraft head together with cast sleeves, which I am sure could be sourced.

Regards
Jason

What typ of mig wire did you find? Where did you get it from?


TOm

[RWD fords rule]

What typ of mig wire did you find? Where did you get it from?


TOm


Here is where i found out about the mig welding wire, http://www.chevelles.com/forums/archive/index.php/t-153864.html


Available from Crown Alloys.com (http://www.crownalloys.com/products.htm)in america.

Their Royal 44-30 mig welding wire (http://www.crownalloys.com/page12.pdf)is what your looking for, it is quite expensive but absolutley worth it.

Go for the smaller 0.035" diameter, costs about $49 per pound and delivery is about $50 - $60 for a 1 or 2 pound role, can be used with Argon or Co2 gas.

I believe the Royal 44-30 is very high quality mig welding wire suitable for welding cast iron and also cast iron to steel.
The wire is an alloy of several metals, the weld is strong yet very malleable/ductile with up to 35% elongation, this means the weld can be stretched and pulled by the cast iron without cracking.

Pure nickle rods are commonly used for welding cast iron because the weld will not harden but it is very prone to cracking and in my opinion using pure nickle rods for welding cast iron is a really bad idea, very hit and miss.

If the wed area is perfectly clean and both pre and post heated to cool down over about 30 mins I am very confident the weld would be perfect every time and consistantly crack free.

I would like to encourage more sharing of information on here, afteral we are here for a good time not a long time:)

Regards
Jason

[DarthVader]

Thanks Jason, will see if it's available here in RSA.

Got this mail after enquiring at JP Motorsports about the head they make :

"The cam is one of my own grinds and is close to 16mm lift and about 304deg, this profile can only be used together with titanium valves.The cr is 12.5:1 but can probably be adjusted to 13:1"

Enough lift !

Why titanuim valves ?

[Lilljebjorn]

The guy I spoke to said that the head was very difficult to make, hense the price. I think he may have welded some sort of pipe into the head but I could not be sure of that. He said that this job alone took most of a weeks work. The valves, retainers etc were titanium to reduce weight. He was getting max power at 8000rpm with max rpm 9000rpm plus. Power was supposed to be 250bhp from 2 litres


Tom

JP uses an insane in house design of camshaft with 16mm lift... From what I've heard he spent a hell of a lot of time on the pinto head. I think the official power of the top engine is 257bhp out of a 2.0 with a in house developed roller barrel injection that's a lot like the super touring injections. He is a great engine builder:thumb:

[RWD fords rule]

Thanks Jason, will see if it's available here in RSA.

Got this mail after enquiring at JP Motorsports about the head they make :

"The cam is one of my own grinds and is close to 16mm lift and about 304deg, this profile can only be used together with titanium valves.The cr is 12.5:1 but can probably be adjusted to 13:1"

Enough lift !

Why titanuim valves ?

I have a roller cam here with 16.5mm true valve lift, will be quite a while before it goes together but will be worth the wait;)

The reason for using titanium valves is because they are far lighter, lighter valve train components allow you to use less spring pressure for a given cam profile or much faster valve accereration for the same spring pressure.

Basically the lighter the valve's, rockers, spring caps, valve locks, springs etc the more power potential your engine has.

Valve spring design is also very important, modern behive springs are much more stable, lighter and use a smaller diameter spring cap, again you can use less spring pressure or a more aggressive cam profile for the same spring pressure.

F1 engines do not use vave springs, they use air pressure to close the valves which allows them to use insanely aggressive cam profiles and massive rpm.

The quicker you can open the valves the more bhp and torque your engine will make.

Regards
Jason

[DarthVader]

Ahh thanks, I've got a set of titanum valves comming from USA, this will be purley experimantal as I still need to find someone willing to try machining them:D

They where cheap so if it can't be done they will be fancy mantal pieces

[DarthVader]

Would a big bore 13:1Cr race motor with a downdraught head need a cam with lots of valve lift or duration, or both ?

I would think lift.......

[RWD fords rule]

Generally with any engine the more lift the better, for mild road you want a very spikey profile with the highest lift you can get.

For a race motor I would be aiming for 16.5mm lift, 300 to 310 deg max seat timing with a very aggresive lobe profile, you will need roller rockers, longer valves and strapped towers for a cam like that.

You would be looking at 250bhp+ with a full on downdraft head and everything else spot on.

Regards
Jason

[DarthVader]

So a Kent RC31 would be more suited to our current motor than the GTS7 we have?

[RWD fords rule]

So a Kent RC31 would be more suited to our current motor than the GTS7 we have?

What cc are we talking 2.0, 2.2?

The Kent RC31 has a awful lot of duration, it would give a very peaky power band, not what I would choose for racing unless you had a very close ratio gearbox.

A 2.3 motor will need more lift and slightly more duration than a 2.0 will, for a non roller cam I think you will need at least 13.5mm valve lift for the sort of bhp you are looking for and about 310 - 315 deg seat, I don't like going too high with the duration as it will kill low down power.

Regards
Jason

[Graham]

if its a BIG capacity motor then i'd be temped by the RC31

ok it aint no pinto, but my m10 2.5 beemer engine has a 336 degree cam in it which is more grunty everywhere than my 2.0 version running a milder 316 degree cam

[RWD fords rule]

if its a BIG capacity motor then i'd be temped by the RC31

ok it aint no pinto, but my m10 2.5 beemer engine has a 336 degree cam in it which is more grunty everywhere than my 2.0 version running a milder 316 degree cam

Yep, if its a 2.4 or 2.5 then I would definately try the RC31

I think I remember him saying its going to be somewhere between 2.2 and 2.3.

Much more important is duration @0.050" lift

Personally I would go for a roller cam for any highly tuned pinto, the difference in valve acceleration is massive.

I have a cam here with only 288* seat and 258* @0.050 with 16.5mm lift, try getting all that out of a non roller cam lol.
As a comparison it reaches the same full lift as a HT1 cam at only 55* atdc instead of 106* for the HT1 with equal valve lift timing at tdc, slightly increase cylinder filling lol ;)

Regards
Jason

[DarthVader]

Roller cam is out the question at the moment but it is the ideal.
Will be close to 2.3 yes.

[loop]

More JPM
http://www.jpmotorsport.se/s/reportage/jpmotorsport_bilsport.pdf
http://www.jpmotorsport.se/

[DarthVader]

Anouther 3 runs on the dyno today just to check if all is still well - 154Kw and 237Nm. But the ugly dip power is gone - smaller chokes fitted