Oettinger, Graf, KR and ABF heads - How much do they flow?

Ok all, a little bit of background. I am looking to get on or around the 250 bhp mark from a N/A 2/2.1 L 16v (I know, I know, isn't everyone). From the threads and articles I have read, I am wondering if I stand a better chance of reaching these figures with a different head, i.e an oettinger, or if I could find one, a Graf. Does anyone have any comparative flow figures for these different types of head compared with the VW types listed above? It seems to make sense to ask these questions before I embark down one road or another,

Thanks in advance,

Neal.

 

250hp from a valver will cost you at least 10K - irrespective of route - is this what you are thinking ?

 

I was hoping for closer to 5k rather than 10k, however, all in, yes, I suppose that is ballpark. Also, with this type of specific output per litre, if this is done properly what sort of life expectancy could I expect?

 

250BHP N/A motor is one that would need a fair amount of rpm to spin a decent amount torque if "BHP" is you goal. This will involve many modifications to the std motor to make extremeely efficient at processing air at 100kpa or less and many compromises to keep the torque range as broad as possible.
Just my 2p. For a listen to RobT.

 

why? does it have to be NA, and are you restricted on capacity

250 easy from a turbo/blower

 

go for it Neal !! i can understand him , the fact of having a n/a car faster then many turbo`s is just so cool , if I had 10k I wouldnt think a sec about dropping a turbo , n/a all the way ;D but Il have to stick with 180bhp out of 1.8 KR goal ( comming soon ... I f... hope )

 

I was reading the other day a thread on vortex about the oettinger heads and how much they flow. It was measured they flow more than a stock KR but simular to a well ported KR head. But the real gain was the why the oetinger flowed and mixed the fuel resulting in a better burn.

Don't quote my figures here as it was from memory ill try and dig the thread out.

Here is that link, read all the pages for some interesting info on the oetinger heads etc... seems parts are hard to come by/have to have them fabed.


Heres that quote from vortex about the flow...

and some more...

It seems you would be much better of getting a whole engine, as the crank is steel and beafy, all built for much higher revs.

 

or transplant a duratech or vtec.....

 

just supercharge the thing for half the cost!!! lol

Would be an awesome engine though and if you have to burn then go for it!!!

remember though that the Honda S2000 makes 240 bhp from a 2.0, and is considered one of the best engines around, NA anyway.... good luck

 

Great stuff guys, thanks for your inputs, however, it will definately be the N/A route I will go down. So, back to the boring tech speak and flow figures with these different heads etc...

 

ok someone had a link to wossner pistons that came in about 13:1 CR, they'd help a lot with the 300+deg cams you'll need,

I have suspicion that those in the know use mk4 crossflow blocks these days...not sure why tho

 

I think the bottom end is pretty simple, there is not that much that you can do other than balance and knife edge the crank, add light balanced forged rods, forged HC pistons (which would vary depending on head type), a possible re-enforced girdle across the bottom, arp it together. Job done...I hope.

Top end on the other hand offers a whole number of different possibilities...but I could be very wrong...

 

When Brian Ricketts was working on the KR 16V heads a few years back, on std valve sizes, these were doing 106 cu ft/min inlet and 92 cu ft/min exhaust, both at 10in WG pressure. These were thought to be very good flows and were 22% and 39% improvements respectively over standard.

I have never seen flow figures for Graf, Drake or Oettinger heads and there is nothing listed in one one and only detailed article I have on Drake tackle - 33.7mm intakes and 29.6mm exhaust valves. The Drake engine had 82.5mm Bore and 90.5mm stroke and ran 14:1 with methanol. Result - 257hp and 162ft lb at 8250. Max torque 181 ft lb at 6500. Given this was back in 1984, thats very impressive. Never seen one though.

The Seat Ibiza F2 Kit Cars were 260hp from full house Lehmann engines - short lifetime and 10K pricetags.

Have some flow figs for 20V's somewhere - will look them out

 

A well balanced breathed on NA 20v running ITB and EFI will make a great engine, cheaper than a Graf, drake or Oettinger.

If you are sticking with the KR then a GTi Enginnering crank might be a good idea, chaep and steal so it will be strong and able to rev high.

 

I have a 92.8mm GTi eng crank already, ready for the knife edge and balance prep treatment. I'm not really interested in 20v, I want to keep the car "period - ish" if that makes sense...

 

By running say 83.5mm pistons, will this enable larger valves to be put in, or is the restriction on the internal edges of the valves (i.e are the valves too close together?) With bigger valves we get more flow. Does anyone know what the maximum valve sizes that can be put in these respective heads?

 

theres an oettinger for sale in the classifieds right now.

 

are you sure you realy want to go n/a as i am building a engine to hopefully make 235 bhp and your 5 grand will instantly fall in a hole in the ground,as rob t says 10 grand is closer to the mark

 

E30 M3 with some work?

I'm sure you are a VW man at heart but building one of the 4 pot motors in an e30 M3 for high revs would be great fun.

At 10k you might even be able to buy close to 250bhp with a car thrown in for free...

 

I'm suggesting the whole car BTW - not just the engine...

Hmmmm