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I believe you can fit the Supra 7MGTE valves, but the stem needs cut and the collet grooves machined back in place as they are too long to fit the E series head.

Supertech do off the shelf valves.

Supertech also do Viton stem seals

Certain Supertech also do springs

Someone does bronze valve guides (can't think of company name)

Camshafts:- Speedvision, Ivan Tighe, Tuning Developments are the only ones I know of that are billet. I wouldn't touch regrinds in an E series head due to the meshed camshaft.

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Im currently having one built by rob at pec. (Used to build tmd engines back in the day).

Im having larger supertec valves put in. 

Also solid buckets too.

Obviously ported otherwise be no point in larger valves.

Stronger valve springs as well.

Will be staying stock cams as want driveability.

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Keep us updated then Jay, id like to see whats what.

 

Was looking at speedvision cams, 270 / 280 they say though.

 

Sure Tighe will do customs though.

 

Bronze guides, Martin has them in his head, crew out in Malta did them.

 

Was checking out a few old threads, Adam you and Phil were chatting away about valves but thread hit a dead end.

 

As for springs, do not laugh, aussie crowd on ebay have some.. i went and bought new standard ones though as i wasnt sure.

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On 24/10/2017, 11:50:49, Calum122 said:

What was it now, the ratios are way out and you should only look to increase the exhaust size, not the inlet sizes.

 

i have a vague recollection of this, it was in a book, don't remember which one. The theory goes that its rarely an issue getting air into a turbocharged engine as the turbo is forcing it in. The trouble with a turbocharged lump is getting the gasses out of the cylinder after combustion, this is because of the resistance caused by having to spin the turbine of the turbocharger. In this book there was an ideal ratio between the inlet vs exhaust valve size. It would be good if someone could remember what book it was, its something I'm looking to try out in the near future.

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2 hours ago, pockrockgtti said:

i have a vague recollection of this, it was in a book, don't remember which one. The theory goes that its rarely an issue getting air into a turbocharged engine as the turbo is forcing it in. The trouble with a turbocharged lump is getting the gasses out of the cylinder after combustion, this is because of the resistance caused by having to spin the turbine of the turbocharger. In this book there was an ideal ratio between the inlet vs exhaust valve size. It would be good if someone could remember what book it was, its something I'm looking to try out in the near future.

Its hardly this?

https://www.cartechbooks.com/performance-automotive-engine-math.html?utm_source=DIY_muscle_car&utm_medium=top_blog_promo&utm_campaign=diy

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Oh, I was refering to what Adam said about Starlets not having an EGR, instead they restricted the ratios.

From what I remember. I just wanted to clarify whether it was the exhaust or intake that needed modifying. But from you're saying, I think it's exhaust.

 

Graham Bell's Forced Induction Performance Tuning is a fantastic book for all this information.

 

http://www.ebay.co.uk/itm/Forced-Induction-Performance-Tuning/262704066797?epid=94999639&hash=item3d2a61f0ed:g:knQAAOSw~l1Z7Vql

 

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Bring to ratio upto 88 to 90 per cent region is a good area to aim for.

1mm oversized exhaust valves will gain you power with a ported head to match etc.. and its power through the rev range.

Very excited to see mine next year as be a direct back to back results.

Edited by jayc-glanza17
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The E-series cylinder heads were used as the "Eco" range of Toyota engines back in the day, hence why the camshafts are meshed and the valves are small.

The exhaust valve is kept small for "internal EGR", whereby you don't get the burnt gas escaping through the valve and therefore burn it again, much like today's EGR except they use a valve and the ECU controls when it opens dependent on driving conditions. EGR is bad on a performance engine as you don't want residue burnt gas left in the cylinder as this takes up room for fresh oxygen!

This is no good for those that want to tune the E-series, and I've seen over the years people changing cams and losing 50 ft/lbs in the low-mid range, I don't know if anyones ever driven a Honda, but that's a third of their peak torque :D and we all know how Honda's lack torque to begin with!

 The exhaust valve should be as large as you can possibly fit in the E-series head, I worked out it needs to be 2mm oversize to get close to being a decent ratio, intake-exhaust. I don't believe there is even enough meat on the chamber to get 2mm in there, it might just be possible but there would be no flow round the backside of the valve. If you're feeling adventurous you could weld the intake valve to make it smaller.

For anyone doing head work, I would recommend the first place to start is at the valves, and only change the exhaust side. I did once design the "ideal" valve for the E-series head, 27mm diameter, 6mm stem, undercut to 5.5mm. I've probably still got the file for it somewhere.

For reference, and I spent a long time looking into it before you can use the following parts from Toyota 4AGE 16v

- Valve springs

- Valve retainers

- Stem seals

- Valve guides

Supertech does aftermarket parts for all of the above.

I've said it before and I'll say it again, this engine does not like long duration cams unless it's for drag racing. The best cam for this engine is the stock one. Toyota got this cam pretty bang on the money and I wouldn't see the need to change it. Turbo motors are extremely fussy when it comes to cam specs and 98% of people spec them incorrectly.

Edited by AdamB
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I've read many a post on the various starlet forums over the years and seen many views/approaches/opinions/combinations. I've spoken to many people ("experts", average joes, backyard specialists, performance enthusiasts, etc.). I've seen many posts and sometimes dyno results with head porting/polishing, uprated cams, valve work, uprated spings, adjustable cam gears and various combinations.

1) And here's my take when it comes to the 4e/5e head. For the most part and average build, i'd leave it alone. It seems to give you 350bhp++ in some set ups, can rev to 7500/7600rpm (some even risk 8000rpm max but i'm not sure if that may induce more valve float?!?) , gives good drive-ability throughout the rev range. I suppose our engines are pretty old now and in some cases the heads need a decent refresh (valves and stems cleaned/checked for tolerances, valves seated properly, valve stem seals changed, inlet/exhaust cam lobes checked to make sure they are within spec, valve/cam clearances checked and adjusted as needed, etc.). A decently rebuild oem spec head actually performs quite well (no oil or air/vacuum leaks),,,i'd guess it would satisfy many builds from ct9 to td05 sized turbos

2) now saying that, i do think the stock heads can be further improved IF done properly ---remove casting marks, minor port and polish work to match manifolds. again, this is not massive head work i'm talking about yet. And it should not cost you an arm and a leg to get it done. If you are handy and have the tools some persons risk doing it themselves, but its usually best left to people who know what they are doing or if you are lucky enough to get guidance from such persons.

3) now for the serious racers/builders looking to get every ounce of power out of the car, i'd say 350/400bhp +++  and high revs (8000/9000rpm). This is where all the above head work comes into play and for sure you should get an expert to undertake this work because it needs to be perfect, no room for errors with larger valves, angle cuts, port and polish and flow tested, uprated springs/valves/cams in combination. 

4) i've noted a few "backyard" people do seriously modified heads with good/great results, but it usually does not turn out well for many who try it. Also, the people who usually got it done after much trial and error and/or from years of experience in the area don't usually tell you their "secrets"   

so imo, options 1 and 2 are for the average builds, while options 3 and 4 are for the serious projects

PS - on a side note and maybe a separate tread, sometimes and i repeat sometimes persons install massive short runner aftermarket intake manifolds and massive throttle bodies that are not well suited to their modest builds (ct9, tf/td04/vf3x/vf2x/td05 running 0.5-1.5bar)  which shifts the power band to the right (higher in the rev range) and then "erroneously" determine that head work is needed to correct the issues. No, its not, your inlet manifold may look pretty/blingy, but its not suitable for your set up, may be revert to the stock manifold or a proven aftermarket manifold which will work with your set up. 

Edited by gorganl2000
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On 26/10/2017, 22:59:59, 5e colin said:

am i reading this wrong or what  ??? theres feck al 0.0000 % anything like egr on our 1986 design engines this engine was designed waaay before any that crap  

the head is eco indeed but not for emisions egr etc crap 

Why don't you read what I put properly.

The idea is pretty simple, try sucking on a straw which is only 1mm diameter to get a mass flow rate of 20 kg/sec... You can't.

Same logic applies to an exhaust valve that's too small and you can't expel X kg of gas.

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http://www.ipg-supertech.com/Complete-Supertech-Black-Nitride-Intake-and-Exhaust-Valve-Set-Standard-Size-for-the-4AGE-16v-Corolla.html

 

Standard 4age exhaust valve 25.5mm

 

I am guessing the 2mm oversize are too big for a 4e

 

Found these aswell, supposed to be 4e specific, 25mm

 

 https://www.tjmotorsport.co.uk/proddetail.php?prod=TEVI-0175

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7 hours ago, daniel_g said:

I was up speaking to the dude who built my engine, he says he would do the machine work no problem, but said its fairly pointless haha.

i'd not say its pointless...lol....it really depends on what you "need" from your engine vs what you "want" to have-----there is a difference 

i do admire your builder's honesty though (and honest tradesmen in general)....some builders would gladly take you money knowing that the work they do would be relatively useless for the project

but as i said above, for the average project a stock rebuilt head (you could even do some very mild port/polish work) will usually be enough

i suppose some people like to say i have "a race spec head that can rev to 10,000rpm with massive cams and larger valves" on the car (which ironically "only" runs a hybrid ct9/td04/td05)

Edited by gorganl2000
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I wouldnt say pointless either haha. He is a local engineer, top man, builds a lot of engines. Mine has already has a mild port to both sides by him.

 

He said when initially building my 4e that head studs were a bit unnecessary aswell.

 

He has build a few 4e engines that have ran over 300bhp with a stock head, and there are better ways to spend 1k area. Which i do agree with but i will have more headwork done at some point.

 

Was just seeing what could be done, now i know most of the 4age stuff works so thats ideal!

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