Static Compression

[ae174agze]

theres a fella on toymods i think that made like 250 rwkws or some massive number in stock slugs

[Sam_Q]

300kw, he goes by the username 30psi-4age and its in an cortina, increadible effort. He feutured in Zoom recently too.

Edited September 3, 2008 by Sam_Q

[Jono]

isn't it a mk1 cortina?

[Sam_Q]

yeah I got mixed up, thanks for the correction

[beerhead]

Yeah people say that they're better all the time, but isn't it funny that one of the fastest FWD drag cars in Australia is based off a 20V? He's only being beaten by the 2.2L VTEC honda turbo's :D 600cc disadvantage!!! He previously ran a 16V head and got more power from the 20V blacktop one when modified, and it spooled earlier.

 

 

The standard 20V with a turbo will make more power than a 16V in standard form, longer duration cams and a better flowing inlet would probably have something to do with it.

 

Honestly, I can't wait till someone actually goes full house on a 20V in atmo form. I was playing with an 03 YZ450F 5V head yesterday... mmm titanium valves - will know soon if they fit a 20V :wink: They make 43.7kw and peak torque at 6500 rpm. The 2008 4V version makes 44.1kW and peak torque the same rpm. Under 1% gain going to 4 valves. Not really something to rave about. I honestly think a mild to moderately built 20V with modified VVT advance to ensure non interference would outperform a 16V of the a similar build. It probably won't make more peak power on the dyno, but the torque delivery will be superior due to a retarded inlet cam at lower RPM.

 

 

i'm not sure if the quad throttle bodies, lighter rods and extra inlet valve will make much of a difference once you go forced induction, could be wrong.

 

most of the high powered 4AGTE motors are 16v.

[Sam_Q]

while this is tottaly off topic in theory over a certain diplacement a 5V in atmo form is inferior which I can explain if wanted. Forced induction engines are different again and while I don't know for sure I have a hunch they are the beter pic.

 

The biggest thing that stops a highly modified 20V making big power is the pissy bucket size, because of this the max cam lift is about 9.5mm and hence it limits how aggressive a cam can be run.

 

This is why I was looking to build up a 7afe head, which is something I may never see happen now since the place I was going to send the cams has closed up shop

[Jono]

Yeah people say that they're better all the time, but isn't it funny that one of the fastest FWD drag cars in Australia is based off a 20V?

 

Don't get me wrong, i think the 20v is really a work of art - power output is amazing from factory for a 1.6l. As for the 16v, I wasn't saying they are better, i was just saying you see more of the higher powered 4As being turbo 16vs. I think the 16v turbo is probably a lot cheaper to do and set up, especially for RWD applications.

[original]

I think the 16v turbo is probably a lot cheaper to do and set up, especially for RWD applications.

 

Correct, especially since most RWD engine bays these are destined for are tiny (ie firewall bashing for dizzy)

Low cost is due to old vehicles being mass produced. 20v are still relatively new/hard to find

[beerhead]

If you're going turbo, you need an aftermarket ecu anyhow, no firewall bashing :D You can build a 20V turbo for close to the same money as a 16V turbo if you run GZE pistons. The only extra expense is a custom plenum. I wouldn't be too scared about interference motors snapping valves. I only know one person who's managed to snap a timing belt. Buy a HKS Kevlar belt if your worried.

 

Sam. We've had this chat before, re-read it if you can't remember. I'm saying a mildly built 16V vs 20V (say 270 / 9.5mm lift) with the same spec apart from the heads, the 20V will win the race hands down. Peak figures on a dyno are very misleading, neither are going to be a dyno queen motor. But I think you underestimate how much the VVT helps bottom end torque if you're smart in your build and retain its functionality.

 

If you need weld and grind cams and no-one down there does them get on the blower with Tighe cams in Brisbane. I hope its not them who shut down, there a great mob to deal with, and are world renowned for their custom grinds.

 

What I don't get is sam, you know heaps about the 4A series motor. Your motor runs a custom inlet and tuned length extractors, but, you don't run an aftermarket ecu with a tune to suit Australian fuel and the variables you've changed in your motor, seems like a waste of all that hard work.

 

BTW,

There is normally 5 - 6 20V's down at BMI for $750 a pop at any one time, I've never known anyone to have difficulty obtaining one.

Edited September 8, 2008 by beerhead

[KE ping it real]

BTW,

There is normally 5 - 6 20V's down at BMI for $750 a pop at any one time, I've never known anyone to have difficulty obtaining one.

 

Agreed, the market is flooded with silvertops at the moment

 

Ke25 racer was trying to sell one for $400ono CHEAP

They are everywhere

[Sam_Q]

yep sorry bearhead my memory is bad sometimes and I still agree with you on the original point and the ones you make here.

 

As for me and an aftermarket ecu I am suprised it has taken someone this long to point it out. Putting your politeness asside, with my current mods if I was planning on keeping my ecu original it would just be stupid, simple as that. the reasoning in what I have done is because the stock ecu with its DLI converter came with my original engine package, however I own a wolf 3d V4 and its bits and I am slowly learning about how to make it all happen so I can wiring it all up myself. I have had enough of stock ECU's from the lack of indications of whats going on alone. Unfortenetly I have way too much on and I wont be able to do much work on my car for atleast another 6 months. Oh and BTW my extractors are crap too, I have lost count how many times i have made something now only to find out I should of done it with different parts/dimentions.

 

I also agree with you on 20V prices, i think they go really cheap.

 

 

 

Anyway back on topic I think that the acl performace series is appealing in one way that hasnt been mentioned, yes the 4agze pistons are proven and are a failsafe option however the acl (mahle) pistons are unusally light at 284g + a 75g pin, so a total of 359g. A stock silvertop piston on the other hand is 285 for the piston with a 88g pin (373 total), so its lighter than even stock! I don't have the weights for a 4agze piston right now which is a bummer, but by memory they where a fair bit heavier.

 

Picy:

 

 

I have to say it looks nicely machined

 

 

Me personally if I was to go the turbo road then I would use these Mahle pistons but then run a 0.8mm gasket and shave the head considerably to get 10:1 conmpression. That coupled with the TD-05 I have for this job and I think it would be a nice package.

Edited September 8, 2008 by Sam_Q

[cuzzo]

Just one thing which could be a problem with the stock 20v turbo if you go too crazy. Rods.... Thinner = lighter = rev quicker = weaker.

[Sam_Q]

only for a blacktop though and spool rods are pretty cheap these days and again like the acl pistons lighter than stock for both the silver and blacktop:

 

silver: 504g

black: 486g

spool: 459g

 

weights with bolts but no big end bearing

 

also i thought it was only revs that killed rods once they where past a certain thickness? Having more pressure in the combustion chamber should reduce the load on the rod because the higher compressive force counteracts the inertia force of the rod and piston which is almost always greater. Normally the highest load on the rod is during the cam overlap period because theres no pressure to hold anything back.

Edited September 8, 2008 by Sam_Q

[cuzzo]

Well really i was basing that on most reports found on the internet with no real testing by myself. So I'm open for a flaming to be proven wrong. Jeez those spool rods are light!

[Sam_Q]

no problem, yeah spool rods seem to have a lot going from there, I am hear reports of super tight tollerances and that weight wasnt official, both the silver and the spool weights are from me directly:

 

 

 

One thing I have no clue about whatsoever though is what difference the reduced weight would have in real world use.

Edited September 9, 2008 by Sam_Q