ALFAGTV6.COM

[Dennis]

Well I've long gone past the trackday budget. I'm just trying to save where possible and work my ass off for the needed budget. What I mean by a big hp screamer is 240 hp with the TS engine. I'm guessing, around 200 hp will do for now and keep cost where I still can afford it.

If I choose to keep the CR down, I can use standard pistons and save 500-600 euros there. I'm using standard rods (lightened, balanced and shotpeened) and probably won't go over 7200 rpm. I can have the pistons made to any design I want from JE blanks, but if i don't need it... I really don't know about the cams... What lift, what duration?

Jim suggested C&B 115.303 but they're out of production...

[Micke]

I'm sorry if this sounds negative but 200 hp at 7 krpm is very difficult.
A simple calculation says that you need a mean combustion pressure of 12.8 bar (at 7k). Now, if this doesn't ring a bell the various M3's had 11.2-12.4 at max power. And they are 4 valvers. F360Challenge Stradale has 12.3 and 996 GT3 12.6 bar.
I don't say it's impossible but then you really need to tune the resonace frequencies in your favour - which again will hurt low end.

My 5 ct is that it is virtually impossible to make a nice broadband 2.0 8V alfa with 200 hp.

I also don't know many 2.0 (8V) Alfas with 240 REAL hp. This requires 8500 rpm which is possible but then piston weights etc start making a difference. Then we also don't talk about service intervals of years anymore.

Correct me if I'm wrong.

And if someone has power and torque figures of strong 2V/cyl engines (street or race) I'm all ears.

[Dennis]

Hey Micke, glad you chimed in. What can I say, I'm a terrible optimist

I appreciate all the input I can get. I know that a wide torque band (for a racing engine) will compromise top end. I think I will need a wide torque band since I'm not a very experienced racedriver and will go to tracks I haven't raced much or at all. A wide torque band will allow me to make minor mistakes without big consequenses in lap times.

You're not wrong. There is one TS engine here which made 230 hp on the dyno last year. I believe it was at 8000 rpm and it has all the goodies such as special rods and very light forged pistons and has cost a fortune. But this is the engine with 10.5 or 11:1. I don't know what the exact wheel hp was.....

I don't mind coming in at 190+ hp as long as the engine makes good torque. Another engine made 191 hp at the same dyno and still had a remapped motronic on it, standard intake with the AFM! It has the C&B cams I mentioned before, forged pistons and all the balancing work which will be done to my engine. With a good ECU I should be able to beat that won't I?

Anyway keep the ideas coming. The good thing is I will post all dyno sheets and specs up here so we will know what the engine does when it's finished in 2 months....

[MD]

Hey Mats, Maurizio. You're right. They said the same thing about the Sydney Harbour Bridge but two hundred year later the sucker is still standing. Yeah I suppose you're right again, it hasn't got 16" wheels. I knew I overlooked something.

Suprised at you Matts. I seem to remember you being a weight saving freak (and everybody interested in racing should be). So in this occasion I am trading off a theorectical need for some practical weight loss.

Hey, nevertheless I appreciate your feed back and anyone else considering using this info should do so with this little debate in mind and chose the solution that suits your racing requirements. I make no claims on being any roll cage construction expert so don't follow me cause I am following Navman...what? Zulu ? No, of course I dont speak Zulu. Dam it, I knew I should have followed my instinct at the frigging big round about with the 14 turn offs..This in nowhere near Melbourne..

[Maurizio]

I don't mind coming in at 190+ hp as long as the engine makes good torque. Another engine made 191 hp at the same dyno and still had a remapped motronic on it, standard intake with the AFM! It has the C&B cams I mentioned before, forged pistons and all the balancing work which will be done to my engine. With a good ECU I should be able to beat that won't I?

I'm no expert but I'm not so sure a different ECU will per definition do allot better. Remapping when done correct would work well enough.
Although moving to another principle of measuring for required fuel is beneficial, less restriction on the intake.

But it looks like the numbers are very optimistic for a balanced, near standard engine and just new cams. There must have been done more to the head to flow enough to get such numbers.

[Mats]

Suprised at you Matts. I seem to remember you being a weight saving freak (and everybody interested in racing should be). So in this occasion I am trading off a theorectical need for some practical weight loss.

Your theroretical need will become practical very quickly in some cases...
Who cares if the cage/car is light if you can't race it? Safety is important to me as well, I have worked with automotive safety and my view kinda shifted after that.
For cage reference you might wanna check out this, page 7 and onwards
http://web.sbf.se/regler/up/4/TR_7.pdf


Maurizio: Must have been one of those "Standard" engines. You know, the ones with only "Standard" parts that seen to run very well...

[Dennis]

The engine wasn't standard at all. C&B cams, ported head, forged pistons, shotpeened and balanced rods, everything else balanced BUT with the standard intake manifold, AFM and remapped ECU.

I wasn't claiming it was a standard engine

Losing the AFM and standard intake would allow for some more horses don't you think?

[Maurizio]

C&B cams, ported head

Ok, in you're post before I didn't read ported. So for me standard engine , the other things listed are needed but won't make more HP. They are just needed to get the engine strong enough to keep up with more Hp and rpm's

Yes, no afm is less restriction, so good for a few pony's but standard intake chamber isn't that bad. (much weight, yes)

[Jim K]

Hi guys,
Figured I'd put my 2 bits here...I don't think there's any way on earth to make 200hp with 10.5CR and 308* cams.....if you work out the Dynamic Compression Ratio (DCR) it'll be piss-poor and the number has to be between around 9 for good results, max 9.5 if detonation is well controlled.
Micke is right also, 200hp under 7000rpm?? Haven't seen it happen with 2liter engines. If you expect 230-240hp...I'm all ears on how to do it. Special head jobs with welded/added material can give you ~130cfm with big valves though, not 44mm. For that kind of power you're looking at ~8Krpm, that would mean 315 to 320* cams, which in turn would mean CR higher than 13:1 for a DCR of ~9-9.5. So for me, things don't easily add up (we are talking racing gasoline right? Even with the ELF special high oxygen blends you'd have a very hard time seeing 220hp). When the first book came out (~1993) they had 220hp in UK from the TS with carbs, but it wasn't any good under 4500, plus it had forged everything for 8000rpm.
You've gone a long way Dennis buying good stuff, why not go the extra mile or two for pistons, rods, big valves and super flow head? Don't put a hp number in mind, just do the best you can and play for more on the dyno, THEN you'll speak your own realistic numbers. I've learned not to put very muchcredit on claims people make....the dyno speaks (then we have another big talk about just what it says and how true it is!)
Jim K.

[Dennis]

I can only speak from what I've heard, I don't have any experience. The guy who owns/claims the 230hp TS has sold me the ITB' and intake manifold because he's trying slide throttles and another intake to get more. Who am I to believe?

The man who does my machining has done most of the valve seats and balancing for racing engines here in Holland (including the Spyker Le Mans engines and the 230hp TS) and he says he hasn't done a bigger valve job then 44mm on a TS engine. He is a friend of my father and if I can't believe him, who am I to believe?

I value all of your opinions a lot since I have no knowledge or experience with racing engines. All I can say I only heard contradictionairy stories of what works and what doesn't. I'll have the head ported and have flow numbers taken and then I will ask Jim what cam is best. Then I will have to guess what CR will work with that and I'll just have to suck it and see....

I will have to buy cams, valve springs, pistons and an ECU anyway so I don't care if it is a few hundred euros or more. I just want the best I can afford.

[Zamani]

Dennis,

Since you are in the race group, my suggestion would also be like Jim. forged everything. Is labor cheap there? I think not. So once you put in the engine, you won't have to think about "ahhh....why didn't I spend a little more and listen to the Greekster's advice, I need the extra revs".

Besides the Euro is very strong these days, you can buy JE pistons from Paul Spruell and many types of rods from the US at a 20-30% discount since a year or two ago (Euro 1.00 = US$ 1.27) . Unless this will bump you into another race class which you don't want to be in.

Oh yeah, don't forget to budget for a race video cam setup so we can all see you smoke the 75 IMSA 16V

[Jim K]

No doubt there are very good engine builders in every country, this is not under question. I would like though to get a little technical with some of this: To produce say, 240hp from a 4cyl engine, you need a TOTAL intake flow of ~140cfm per port. There is no way you can get this from a 2-valve head with 44mm valves! Total 140cfm is after the possible losses of any manifold and wide open Throttle body and trumpet. Whether we like it or not, there is always some loss when anything is bolted on the bare head. This means that the head itself must have more than 142-144cfm...this is 4valve territory now! I know that certain 3liter V6 heads with 51mm (!) valves have gone to ~160cfm with huge ports, but thats a long way from 44mm and TS ports! My mild-ported 4v 3liter has 146cfm...so 144from the TS is a bit out of the question for me. Furthermore, supposing this flow is somehow possible, the formula for determining approx. max. power rpm (developed by Superflow) shows something like 10500rpm!! I have no reason to doubt these guys, and even if they're 15% wrong, we're looking at ~9krpm!
Now, getting this power from a 16v is very possible, seeing that Opel motors for example can make up to 280-290hp (QED and other tuners)not to forget Alfa BTCC engines (290-305hp at ~8500). The Alfetta 16v, was making 240-245hp at 8k in 1976, so as far as rpm is concerned I believe we have a picture.
That's all I can offer for now, I hate sounding like Doubting Thomas but most examples say 240hp at 7-7.5krpm with 2 valves is very elusive!
Jim K.

[Mats]

soo, what if one could have 165cfm and 8000 maybe even 8500rpm, what is a reasonable power estimate?

[Jim K]

165cfm..Hahah!Thats a good one, thats what the S2000 showed on the bench and very close to the M3 (over 170cfm) Remember we are rating everything at 10" water pressure! 165 cfm in a 2liter will make best power at 12krpm !! For 8krpm power, a 2liter will have ~110cfm which is a bit poor from what we've seen so far. You can really govern your rpm range with cam selection if you have a very good head. 120-125cfm is doable with 46mm valves so 200hp at ~7200rpm is within comfortable reach.
Jim K.

Hey, Mats, what's with the mug-shot?? Your car was better!

[Mats]

Well, if you stop telling me what I can't do and answer my question?

165cfm @ 10" H2O, 8-8.5Krpm, reasonable power? Assume everything optimized on this side of Beryllium and Tungsten.

Mugshot, a friend has a photo studio and he needed someone to shoot, I got some photos of myself in a pyjamas for it.
What's wrong with it? Don't like my "skull"?