crossflow porting results

[ando76 4,354]

good stuff - c2 head to by the looks and like the stud mount rockers - thinking there is some lift going on there.

 

Not real keen on the head bolts and that bloody XE Dizzy but they are minor things.

 

Sing out if you need a sump and girdle/tray. 

 

fun times ahead by the looks

[slydog 7,873]

good stuff - c2 head to by the looks and like the stud mount rockers - thinking there is some lift going on there.

 

Not real keen on the head bolts and that bloody XE Dizzy but they are minor things.

 

Sing out if you need a sump and girdle/tray. 

 

fun times ahead by the looks

 

Well I didn't even need to read Ando's post to know hat he would have and did say...LOL Shit bolts,shit dizzy LOL

[Clevo120Y 815]

Yeah I agree about the XE dizzy, that will be given the flick, I have a made up an EST dizzy with the TFI guts for a MSD box. I don't mind normal head bolts but I do prefer studs. I have an AU "girdle" and a BA tray I was going to look at modifying to suit, I will probably get one of your modified oil pumps later on. I will strip it anyway and go over the whole thing, might change to a roller cam etc etc, I don't even have a car to put it in yet hahaha.

[ando76 4,354]

I prefer head studs because;

 

a. when you are going into the engine all the time it just saves money on buying head bolts every time 

b. from an engineering stand point studs are more effective at the job and

c. they look bad ass.

 

I don't like XE dizzy's because in consistent high RPM applications the single bush in top of the dizzy wears and then the inner 'chopper' wheel makes contact with the outside and causes a miss at best and then snaps causing a lost race. 

 

Just thought I'd clarify my reasoning. 

 

My girdle/tray is a combination of both the AU girdle and the BA girdle/tray.  I have them on CAD and get them laser cut now after sly's hand made prototype. Four sets of milodon windage tray studs to suit Ford Windsor (4 studs in each pack) and your in business.  But knowing you - you will make your own tray girdle - lol. 

 

Once I get these bloody race motors out of the way I'm going to look at what I have to modify to make them suit Cortina as well as there seems to be enough mad x-flows going into Cortina's to justify the re-jig. 

 

+1 on the Roller cam.  Kev Wyatt wont build a race motor unless it is Roller cam - that's good enough for me - that and his engine has won our title 5 out of the last 6 years (owner of engine didn't race last year)

[Duckboy01 6]

If anyone is looking for an ICE Ignition system I've got one I plan on selling that has only done 3 race meetings in one of my old speedway cars, 7 amp module, pro coil, voltage booster, dizzy and wiring harness. 

[PRO250 1,506]

So i have to ask a few things for the head for my white car. I have to ask as this is not a big cam engine and is also boosted not N/A

So i recut my head to take a bigger valves 1.84 and 1.6 may be 1.56 ill check again tomorrow

So i cleaned up my runners did not make them bigger just tidyed them up some. I opened up and blended to suit the bigger seats. I cleaned up the turn up some so it a nice turn not sharp like they are stock. Its a single cut seat and im unsure if theres a gain from a 3 angle seat? its somthing i left in his hands but did ask if he could do 3 angle seats but its not been and if it works it works im easy ideas a welcomed here.

The exhaust im a little unsure about ive not blended the seat to the full size of the valve or done a nice turn or any decent bowl work as i dont not know what it will do having the exhaust side flowing so well (exhaust vs inlet flow) my cam has more lift and duration on the exhaust side and more lift. Maybe better to spool the turbo? but still be not to much inlet vs exhaust flow? makes sense in my head but i have a hard time sticking it on paper if you get what i mean im unsure if i want more flow here is what im saying?

Now 1 thing ive not done is anything to the valve guide bosses ive left them stock. Its boosted so i dont think the gains would be worth the extra time?. ive spent a fair bit of time on it allready but is it worth it? if it is im happy to spend another few hours on it

Info welcomed i could run with it but im not putting it on a bench so maybe im just looking for a few guys in the know to say its all good mate run with it LOL. Ive just not done a boosted engine and am unsure of myself and being a pussie. I tell you what after reading this thread i know it flow heaps better then stock and since it was making good numbers on a stock engine if this new one does not blow up it may be a beast

[ando76 4,354]

The greatest airspeed gains are made at the seat - full stop.  Cam (my cylinder head guru) cuts 5 angles into his seats and that is why THOR's head flows some awesome numbers. 

 

If you want the best flow possible - get a decent seat cut - It doesn't matter that you are forcing the air in - the principle is still the same, i.e. flow is flow.  The more air and fuel you can get in, the better the bang.  Doesn't matter with its being sucked in or blown in.

 

On your exhaust side I would be blending and tidying and that is about it.  They flow well on the exhaust and on a boosted application getting it out is important as well as it helps to get that turbine happening faster. 

[gerg 10,871]

Turbos work the exhaust valves pretty hard, and need maximum seat area to conduct heat away from the seat, so I wouldn't go cutting extra angles into either one on the exhaust side.True any flow increase is better, turbo or nat asp but turbos are more about pressure than flow, so big ports don't do much except kill off-boost performance. I agree with Ando that airspeed is king and any increase in pumping efficiency will work, turbo or not. Just remember that getting the turbo spooling earlier is done with better low-rpm velocity (depending on your turbo size) so again like Ando said, just tidy up the dags and sharp bits and no more.

[PRO250 1,506]

Cheers guys thats helpful

ando you have PM mate

[Clevo120Y 815]

Hey Dave, As the other blokes have said a 5 angle cut is the go, also a backcut on the intake valves is a must as well. With the exhaust port I just lay over the short turn slightly and clean it up in the bowl and blend the seat to the throat.

[matt_lamb_160 252]

I like the idea of wide exhaust seats on turbo and/or LPG motors for longevity. The exhaust flows well anyway.

[ando76 4,354]

Matt does the exhaust valve on a boosted engine see higher temps than an aspirated engine?  If so why?  I understand that turbo generates heat in the exhaust manifold but I would have thought coolant flow in the head would keep valve seat temps reasonable. 

 

I have to admit to having naff all experience in boosted applications and that is why I will be finally getting my 'learner' turbo x-flow up and running later this year, so I am all ears. 

 

I would have thought the inlet temps with an intercooler would have been similar to an aspo engine. 

[gerg 10,871]

I know that fitting a turbo to a non-turbo diesel or upping the boost on an already turbo'd one requires fitment of a pyrometer to the exhaust manifold. This is to prevent burning out of the exhaust valves. If you think of the compressor side and how much heat is generated by compressing the air, then picture the turbine side that is also compressed (from driving the turbine) and the gases are already hot to start with. The manifold and turbine housing can radiate heat away but the valves never get a break, their only means of heat dissipation is through the stems and seats.

[ando76 4,354]

So the pyro monitors EGT's and relays info to the ecu to increase fuel to cool the cylinder? 

 

I understand the increased temps from the compressed air but I thought that was the role of the cooler - to bring the inlet temps down.

 

I wonder if anyone has a photo of an XR6 turbo exhaust seat.  I'm a visual learner after all.

[gerg 10,871]

No Ando you are 100% wrong lol... No seriously, on a diesel more fuel = more bang + more heat. So if you're starting to cook your exhaust, wind back the fuel and boost will drop accordingly along with EGT. I'm not aware of any factory diesel setup that includes a pyro in the ECU inputs (a factory tune would just be way on the safe side) however it is often used when diesel tuners want to squeeze more out of a particular setup without pushing it over the edge and burning out valves. Anyway I digress.... Petrol is a bit different and you probably could dial in a bit more fuel to cool the charge but the exhaust side might still get hot from unburnt fuel burning in the red-hot manifold/turbine, which is not good for long periods. I know XR6T exhaust valves are made from a different material (InconneI I believe) and possibly the seats too. Seat design not sure of.

[ando76 4,354]

ok that all makes sense sort of.  I am lucky that I have one of the best turbo guys in the business up here in Ray Hall.  He has been around for a hundred years in the turbo game and made stupid power out of an x flow many years ago.  He use to sell autronic ecu's but after an issue he went alone and makes his own Vipec systems now. 

 

I've touched base with him already.  A mate of mine has a very fast  KE corolla with a turbo, 20 valve hybrid motor that Ray did a heap of engineering and design work on so I got to meet him thru Gav. 

 

Fun times ahead. 

[matt_lamb_160 252]

Turbo combustion temps are higher

[matt_lamb_160 252]

Should have refreshed. Missed some of the later posts.

 

Bigger bang, higher cylinder pressure and increased back pressure = hotter exhaust valve.

[ando76 4,354]

Ok I am starting to get my head around it.  We run big cylinder pressure and Big bang with metho but I guess the slower burn of the meth makes for cooler combustion temps. 

 

Hmm meth turbo x-flow.....

[Clevo120Y 815]

Now your talking, meth would be great for a turbo setup.

[XPT 673]

Just slightly illegal for the street

[ando76 4,354]

Yep well and truly illegal.  I'm pushing the boundaries with the current plan.  Probably should get this thread back on topic.  Sorry Sean. 

[Clevo120Y 815]

All good Tony, all relative to porting I rekon.

[Clevo120Y 815]

here is a cross section of a stock C1 head, intake and exhaust

 

Intake

 

 

Exhaust

 

[ando76 4,354]

Nice Sean. You can see the gains in the short turn and also in increasing the bowl and throat x sectional area. But really a pretty good runner from standard.