What 4a-ge 20V turbo cam do you run?

[RT40Corona4AGTE]

I am at a standstill with deciding what cams to use, or have made if i go completely wild and custom and was wondering what you guys are all running in your turbo 4age 20valves? as much info as possible on specs please....

[Jonny Rochester]

A lot of turbo cars use stock standard N/A spec cams, and a lot of normal cars use about 240 degrees duration. Maybe the 20valve has 250 degrees stock, can't remember.

Maybe for a wild turbo setup you can use a "mild" longer duration cam, like maybe 265 degrees. Use a adjustable cam gears. You would set it up with less overlap than on a N/A setup.

[RT40Corona4AGTE]

yes I know overlap is a bad thing for turbocharged engines, just wondering what duration and lift others are running?

[JP]

Kelfords do a 20V turbo specific camshaft set, I'd planned to use those on my build before I changed to a 2zzge instead.

Might be worth giving them a call to ask about results of cars using that spec.

http://www.camshaftshop.co.nz/index...._view.tpl.html

[RT40Corona4AGTE]

lol! one step ahead of ya there, I emailed them about 30mins before I started this thread. Haven't had a reply as of yet though.

[oldcorollas]

their 264 "turbo" cam is the same duration at 40 thou and lift as their 8.2mm NA cam.. but 0.05 more lift than their 8.15mm 264 NA cam

256/264 HKS/TODA/kelfords will all be similar..

if you are not planning to increase lift, then it depends on what rpm range you want..

[RT40Corona4AGTE]

I want a fairly high rpm range, as I dont really mind sacrificing power down low. (street registered drag/fun car). Is more lift beneficial? I am not a guru on camshafts (incase you couldn't tell)

[oldcorollas]

more lift is better unless the vale hits stuff, you spit shims, or you don't gain flow with more lift.

with the 20V it may be physical issues that prevent higher lift (ie, bucket size, valves trying to be in same place at same time)

fairly high like 9000rpm? or 7000rpm?

for drag/fun car, 256 or 264 would nto be bad... 272 would probabyl be too big..

(very) generally.. turbo motor will be a step or two up on the rpm range compared to NA motor for the same cams...

ie (and this is realyl rough) rpm range of say 256 turbo might be similar to 272 NA.... but that also depends a lto on overlap, more than actual duration (hence why kelfords don't put a recommended cam position for the intake of turbo cams)

anyway, you need to consider where you want max power, and when you wan tit to spool by, but that will also be greatly affected by turbo choice... need to consider them as a package

[RT40Corona4AGTE]

oldcorollas - 9000rpm wont be feared by this engine (i hope)...... I want max power in the upper rev range, spool hopefully by 4000rpm - 5000rpm or so, thinking of a turbonetics GTK-550 or GTK-650 or similar. See here for the specs for those two models of GTK turbo http://www.turboneticsinc.com/gtk

272 might be ok, be interesting to go more if its beneficial in the upper rev range, i dont mind experimenting a bit, I will need to work out how much maximum lift I can possibly run somehow, convert to different buckets (solids or something if shims are an issue), I think If i want a bit more lift and larger duration I will go with a custom cam that kelfords offer where I specify what I want.

What are your thoughts mate?

[oldcorollas]

look at what some of the drag cars are running for cams.. i can't remember any specific examples, but you could say.. look at Backyarder (10krpm 4A?), OKE20 (2J), 1J747, MS-75(1FZ?)...

larger lift on 20V is an issue due to small buckets, so that will need addressing.
i'm no expert on 20V (or engines in general ) but more than 272 seems biggish for a fun turbo cam...but depends on so many factors..

[fixeruperer]

you gota rev little motors to get power, you need big cams to get peak hp higher in the rev range. if your worried about low-mid power you are going to have to find a medium, if you want all out power, bigger is better.

your going to have to look at boost vs rpm vs ignition timing vs compression, all of these have a big effect on power. if you dont want to rev it hard you will have to increase boost and less timing, or less boost less timing and more compression, or more comp less timing and more boost.

[RT40Corona4AGTE]

oldcorollas - BACKYARDER replied to my PM tonight and he said he is using Ivan Tighe regrinds with their "1125C" profile. Look here for what their specs are for the 1125C profile. http://www.tighecams.com.au/profiles3/toyotatwincam.htm

He is also pushing a garrett T51 T4 flanged snail with a 0.9 A/R rear and getting full boost around 6500 rpm. Pretty impressive for a little 4A i reckon.

[RT40Corona4AGTE]

the 1125C profile appears to have 285 advertised duration. interesting....

[oldcorollas]

250 at 50 thou.. thats a long cam, but he is not short on rpm....

[fixeruperer]

backyarder runs on meth, meth opens a whole new world of awesome....

250@ .050 is pretty big