4722 replies to this topic

[vocky]

thats how the saab b207 and z20net have their oil jets mounted

[chris]

And they produce more than 400 hp (with a satisfactory reliability) ? Why GM don't "copy" b207 and z20net design on the Z20LEH ?

[alanoo]

And they produce more than 400 hp (with a satisfactory reliability) ?

Why GM don't "copy" b207 and z20net design on the Z20LEH ?

Erm chris,

GM most powerful 4 pot is indeed based on the B207/z20ne* family, remember the 265hp engine in the Opel GT ? In the US it also has a GM certified remap at 304hp with full warranty, with no change in the engine at all.

[steveboyslim]

I am wondering how you can efficiently spray oil in a such restricted windows (when the piston is on BTC) with jets which have been designed for a BMW with another oil circuit and a different engine design.
Moreover your oil spray is strongly disymetric on the bottom of the piston with this design of jet installed on crankshaft bearings.

Compared with with the OEM Z20LET drilled conrods,I am pretty sure that the general efficiency result is worst with this system.

The BMW jets function correctly, I tried many other types, VW, Renault, Ford Fiat etc and with the correct angle they do an excellet job of cooling the underside of the piston.
The small hole in the con rod is there to lubricate the cylinder bores not cool the underside of the piston, but there is enough oil spray from the jet to lubricate the cylinder walls.
Also there is no noticable drop in oil pressure.
The oil jet fitment has been tried and tested on the earlyier C20LET as well as the ZLET, both types of engines makeing over 500BHP (600BHP in two cases)

Steve

[Winstar]

And they produce more than 400 hp (with a satisfactory reliability) ?

Why GM don't "copy" b207 and z20net design on the Z20LEH ?

I've not seen the con rod ones but the oil pressure will never be high enough to over come the acceleration on the up stroke of the piston so you will only get cooling flow on the down stroke, but you don;t need it to constantly flowing as the heat transfer properties of oil are so much higher than air. In fact there is an argument that you don't even need them as you don't need to meet the EuroIV emissions so can map the engine cooler.

The reason they aren't on the LEH is because the base engine achitecture is over 20 years old so from a time when combustion temps where lower. The other reason is that the LEH upgrade was done on a budget GM where most pissed off that they couldn't just stick a bigger turbo on and remap it.

[Nev]

Just ordered another 350 quids worth of stuff and written up some more blurb on theblog about MAFs, air tracts etc.

Things are progressing, slowly but surely.

[siztenboots]

Just ordered another 350 quids worth of stuff and written up some more blurb on theblog about MAFs, air tracts etc.

Things are progressing, slowly but surely.

#
# The inlet air pipe that feeds (roughly) atmospheric air to the turbo compressor housing (i.e. unboosted air).

this actually vents the boosted air back to the inlet , depending on the AMAL valve duty cycle. Its all metered air so the ecu expects to see it.

I would also advise to heat shield the actuator as they aren't totally heat proof and can melt, causing them to run uncontrolled boost (which is scarily fun)

[Duncan VXR]

Nev you need my DG intake kit but alas only 80mm from intake to turbo so you may want bigger? As for AMM use whatever size you want from alloy pipe and weld a boss once drilled / tapped to accept the best bosch sensor. I remember holding the AMM for the v12 Aston - that was a good size Also that turbo will suck the air in if needed but agree 70mm prob needs to go DG Good to see it coming along, I am stuck with mating a vag box to a cossie 2wd box in a samll 7 type race car lol - its all getting a bit much with such little time spare. Next month free to start fully and get things test fitted on loan before buying

[Duncan VXR]

Be carefull with that new rubber hose for the crank breather! Gets warm in there - would have been tempted to mod the original one and use a bender or cut and re weld it. But looks a good fit

[Arno]

Silicone hose (unless specailly coated inside) can't withstand regular contact with oil or fuel so is not suited for an crankcase breather hose. I'd have a bent (steel/ali) tube made, or perhaps a completely different setup for the breater that doesn't need to go up like this.. Bye, Arno.

[Nev]

Steve, I shan'tt be using an actuator as such as my turbo requires an external wastegate that I have just ordered from the States (a new style water cooled Tial MVR). I've ordered a 1 bar spring for it (which will be it's minimum level of boost). The amal valve (which is controlled by the ECU) can then be used to increase this base minimum by the mapper to whatever I desire. Duncan, I'm still in a quandry over what size of inlet track to make. I am currently waiting on 2 sources for info on MAFs, it's bloody hard to get calibration curves and physical sizes out of them as they simply aren;t used to individuals asking such detailed questions. Thankfully, I have already got the exact spec for Bosch 92mm MAF with calibration curve, but it can only flow 1.2 Tons/Hour before the 5v signal will max out. If I tune to 500 BHP then I calculate that I will need approx 1.55 Tons of air/hour - hence I need something in the region of a 100mm MAF. This is concurs by the big american V8s such as the 500 BHP LS7 - that uses a 102mm MAF. If I can't find a larger MAF for sensible money I will take the old sensor out of my 70mm MAF and fit it into my own alu tube and the mapper can mathematically scale up the calibration curve from the OEM 60mm venturi to the new I/D of my alu pipe. However, this wont be super accurate probably. The crank breather hose was wrapped in heat tape today. I was going to make an alu heat shield, but the sapce was too tight, so far easier to wrap it. The airbox is also concerning me, it was only designed to flow for 200 BHP, the relatively small filter surface area will undoubtably cause a pressure loss. I am scared of starting yet another mini project and designing/building a new one with a huge filter off some V8.

Edited by Nev, 03 February 2011 - 10:07 PM.

[Nev]

Drilling and tapping update on the turbo today - thanksfully it all went well. Lots more parts ordered too.

[Winstar]

Duncan, I'm still in a quandry over what size of inlet track to make. I am currently waiting on 2 sources for info on MAFs, it's bloody hard to get calibration curves and physical sizes out of them as they simply aren;t used to individuals asking such detailed questions. Thankfully, I have already got the exact spec for Bosch 92mm MAF with calibration curve, but it can only flow 1.2 Tons/Hour before the 5v signal will max out. If I tune to 500 BHP then I calculate that I will need approx 1.55 Tons of air/hour - hence I need something in the region of a 100mm MAF. This is concurs by the big american V8s such as the 500 BHP LS7 - that uses a 102mm MAF.

If I can't find a larger MAF for sensible money I will take the old sensor out of my 70mm MAF and fit it into my own alu tube and the mapper can mathematically scale up the calibration curve from the OEM 60mm venturi to the new I/D of my alu pipe. However, this wont be super accurate probably.

The crank breather hose was wrapped in heat tape today. I was going to make an alu heat shield, but the sapce was too tight, so far easier to wrap it.

The airbox is also concerning me, it was only designed to flow for 200 BHP, the relatively small filter surface area will undoubtably cause a pressure loss. I am scared of starting yet another mini project and designing/building a new one with a huge filter off some V8.

Appologies Nev you PM'ed me about this before Xmas but I was snowed under as work and i forgot.

in terms of pressure loss due to the diameter then a 1m smooth stright pipe will have the folloing

D[mm]......V[m/s].......dP[Pa]
57.........135.79.......3147.3
70.........90.04........1077.5
80.........68.93........537.1
92.........52.12........259.2
102........42.40........151.4

as for post turbo it still needs to be bigger than a ratio of the inlet and outlet pressure as the temp will be alot higher and therefore not an exact change in density (if you really want to calculate it you need to non-dimensionalise the air flow using m*sqrt(t/p)clicky

Edited by Winstar, 06 February 2011 - 11:43 AM.

[Nev]

Ahha, thanks for your input Rob, I had wondered why you hadn't replied and was worried that you were giving me the cold shoulder for some reason! Anyway, yesterday I have commited to buying all the parts for a 76mm inlet track (i.e. airbox to turbo inlet). Assuming I map the car for 450 BHP my calcs say i will need 675 CFM of air/min, which means the air in this tract will be travelling at an astonishing 253 KPH !! Having comitted to the inlet track I am now considering what the diameters the post turbo pipework should be. I know a rule of thumb is that every major pipe join post turbo should increase in size a bit. At the moment the outlet from the turbo is 44mm. This leads into the Pro-Alloy intercooler which has a 51mm inlet, thence on to the intercooler exit which is 54mm. I am concerned that this 54mm outlet isnt really large enough becuase: 1/ It was designed to flow for 275 to 300 BHP. 2/ Rubber pipe from this has a sharpish bend (prior to the 76mm tophat). 3/ 54mm is simply bloody tiny, the (un-unormalised (for temperature/expansion)) air will be rushing down this at 501 KPH !!! I talked to Duncan about his mod to increase this pipe diam and he said he felt a noticable improvement even with a flow rate for just 300 BHP. Hence I am keen to enlarge it on a 'gut feeling' and basic calcs basis. I have asked Alex at Pro-Alloy to quote me for the work and am awaiting feedback from him. Does anyone else have any input on this matter? Though to be honest, I am keen to get the car up and running ASAP, so I may end up doing what's easiest and then re-visiting issues/bottlenecks in a years time or so. Its been about 7 months since I drove the bloody thing !

Edited by Nev, 06 February 2011 - 02:12 PM.

[Nev]

Hoiked the CC out this evening to send it off to Pro-Alloy.

[Nev]

Most of my new pipework parts arrived last night, so I've started fabricating up what bits I can. Pics here.

Alex from Pro-Alloy has emailed me to say that the Mk2 intercooler I have extracted and sent him understandably isn't intended to take 2.5 bar of boost, so I need to give him a ring today to determine what to do about this. In practice I will likely be running less than 2 bar of boost, but I'd rather get it beefed up and know I have headroom in the future to increase the boost for more power. Also, it may end up that I dump the amal valve and stick a 3rd party manual boost controller in its place. That way I can modify the boost from 1 bar to 2.5 bar depending on what the conditions are.

[siztenboots]

afaik mine is the only mark3 charge cooler, it has extruded ally corner side reinforcements , good for 30psi boost sofar.

[Nev]

Thats interesting Steve, you can clearly see where & why its loads stronger.

I have spoken to Alex at Pro-Alloy now and he is going to replace my 2 end caps with thicker material and replace the back plate with the hanger with thicker material. However, he didnt mention anything about welding on those reinforcing the corners with that angle alu. I might give him another call to discuss whether this is worth while on mine. He reckons these mods should probably be safe for 2 bar of boost, as Wayne is using a similar IC and so are a few others around the 2 bar mark.

I have done an 'enlarged exit pipe' airbox mod this morning, pics on the site HERE. As far as I know, nobody in the VX community has done this so far, and I think this mod would help stage 3 and 4 people as this exit pipe is a narrow constriction (64mm I/D). Its also quite an easy mod to do, took me approx 2 hours with angle grinder, dremmel, file and epoxy. If anyone wants a length of 76mm alu pipe to bond in, i can cut a length off my enormous pipe and post to you.

Edited by Nev, 10 February 2011 - 11:24 AM.

[Duncan VXR]

Nev good progress sir - Think I was the 1st to go past the original cc spec breaking a few and even break the mk2 version so sounds like Steve has the latest beefed up version and know he has hurt a few on the way - I think a decent turbo will not cause as many issues as we see on high boost k04 7 k06/k04 setups tbh Nev I have done the same thing but using 80mm pipework looking at making the whole box out of alloy though but if not will finish modding the bottom section - retaining oe filter size which with the ITG filter flows well over 400bhp (sure it was 465 or 512bhp) cant remember what Andy said now I did look at changing the cc pipe size when I did my kit from CC to TB which was 63mm from CC to TB but kept the smaller inlet side alone due to the horrible bends and small outlet of turbo anyway and from memory was poss gonig to if anything cause some lag on the k06/ko hybrid Looking forward to see how all the small things come together - keep up the good work DG

[Tommess]

Think I was the 1st to go past the original cc spec breaking a few and even break the mk2 version so sounds like Steve has the latest beefed up version and know he has hurt a few on the way - I think a decent turbo will not cause as many issues as we see on high boost k04 7 k06/k04 setups tbh

Have there been any quality-issues re the cc form PA?! Because I want to go down the same route. Actually I'm running 1,75 bar (roughly 26psi) of overboost with a peak of 330 bhp at 5800-6000rpm. It's the Astra VXR turbocharger I'm using.

So is there something I have to keep in mind or tell when ordering the cc from ProAlloy? A hint or something like Mk 2 or 3 chargecooler?

Please let me know! Thanks!