3SGE cams in a 3SGTE

[Jabeo]

Hi all, lately i have been looking into doing the little cam upgrade that some people do to their 3sgte's "while my engine is out". I have already done a bit of research on this and read Thomas' (tw2) old forum thread on the celica forums about this exact install, multiple times to clue myself up on it as well as a thread i found on here from a while ago. I have asked around and also read mixed opinions on the install, where it has a been a straight drop in affair for them, without further changes needed, as well as people who have needed to reshim the valves. ive been told that adjustable cam gears are not totally necessary (but useful) and for some people it has made a little bit of a difference to the response of their turbos and mid/top end powerbands.

I am wanting to know what peoples opinions are on this, as well as any personal experience or thoughts on the install. What is the likely hood of me having to reshim, if at all and why do some people do it while some dont? my car is relatively low kms and well serviced if that makes any difference. I am not saying that i will do it, just wanting to clue myself up some stuff

https://www.alltrac.net/phpBB2/viewtopi ... =3sge+cams
https://mr2.org.nz/forum/viewtopic.php?t=11817

gen 2 3SGE (165ps):
In: 244deg, 8.5mm lift (timing 7/57)
Ex: 244deg, 8.5mm lift (timing 57/7)

gen 2 3SGTE (225ps):
In: 236deg, 8.2mm lift (timing 8/48)
Ex: 236deg, 8.2mm lift (timing 56/0)

[Benckj]

It pays to do your homework and prepare for confirmation of settings to adjust where required. I’d be more inclined to set up a system to degree your cams so confirmation of lift and duration can be checked while engine is out. Adjustable cam gears are not essential but they are very useful for fine tuning after engine is installed or correcting an issue when belt is one tooth off. This is easier to do than you think even when every pre-caution was taken. You may also find that your engine performs better with a few degrees retarded or advanced than the prescribed cookbook figures off the internet. This will only become evident after you place car on dyno and confirm fueling AFR’s.

By no means am I an expert on this subject so others will chime in with some advice & reccomedations.

[tw2]

The idea is that a specific cam wears a certain circular pattern on the shim and therefore a new cam will have irregular grooves on the shim to wear into. I never bothered and never had any issues after many tens of thousands km. However I did check the clearance for all of them. I needed about 4-5 new ones from Toyota. A couple I threw out as I thought the wear was a bit excessive (probably completely unnecessary) and the rest I could easily sort by moving them all around.

You will need a micrometer and some basic math. I can lend you mine if you don't have one. As we discussed it just depends on the effort you want to put in. The best would be adjustable gears and dyno tuning to find the best torque curve tailored to your liking. This process is generally pretty expensive. Otherwise just chuck them in with stock gears or dial them in as Jim suggested to a recipe on the forums and avoid dyno costs.

In any case avoid HKS style 3 bolt cam gears as they can slip. ATS hybrid ones are a good option.

[barf]

sorry to dig up an old thread but I thought forced-induction engines used 'zero-overlap' cam timings? (why would anyone even think of using 3S-GE cams in a 3S-GTE?)

first thing that pops to my mind is there could be exhaust gases still in the cylinder when the intake opens, and enough of a temperature/pressure difference to allow some exhaust gases into the intake (ie; exhaust reversion/blow-back).

if I understand this correctly (no guarantees), from the timings you provide, the 3S-GE cams have 14 degrees overlap (7 each side of TDC), the 3S-GTE has 8 overlap but rotated such that the exhaust is closed at TDC.

[tw2]

Overlap is fine in the top end. It won't exactly help your low rpm torque but there is a good reason why people have been using 264 and 272 hks cams for years in the 3sgte (they were also originally designed for the 3sge). Have a look at some of the old dynos floating around in mr2oc and ats site. 3sge cams are pretty mild at 244 and only 0.3mm more lift.

[barf]

Looking at the specs on those, exhaust closes at 2-after in the '272', which is quite different to the 7-after here..

I just don't want to see people turning nice 3S engines into hand grenades... spinning the exhaust forwards a bit would be required at the very least.

[tw2]

Anyone should ideally be dialing them in not running straight up. Having said that, I ran 3sge cams in a gen 2 3sgte for many years without issue- without adjustable cam gears. Some exhaust advance will always help with spool too.

[Soleman]

Hello Mr jabeo,

Just want to throw 2 cents in here,

Every cam is designed with a centre line, Toyota marked the cam gears and crank to align nicely an the cam would line up where designed, untill wear and machining of surfaces, gaskets etc change the you need to degree the cams to set them up for the desired centre line for those cams, adjustable cam gears are very handy for this process,

id be really looking into the benefits vs the Effort required!.

you would be taking out, cams, removing timing belt, possibly replacing shims, purchasing cam gears, shims, dial gauge and holder, degree wheel, tdc stopper, then there is the time learning the method and then re checking because you doubt ya self (speaking from Experience).

if the gains are substantial jump in, if not maybe look into a set of aftermarket cams if that's what you want, the GSC 268 is an option, i'm running 270 Kelford's, cant wait to hear the lumpyness