karl. Posted September 13, 2014 Share Posted September 13, 2014 Im currently thinking about building a high compression 5efte engine It will be running a td04 or maybe even a td05 if it comes to it. My question is, Do I build a high compression or low compression engine? Low compression will mean: more boost, therefore I will have to buy arp head bolts.less chance of det, so I can run standard petrol.Slower spool time so I would have to buy a hybrid/billet turbo.I will be running more boost so I will have to buy bigger injectors. High Compression will mean, I can get away with standard head bolts since i will only be running around 1.4/5 bar.I will have a quicker spooling engine so I could go for a td05 instead of a billet td04 etcI can run a standard toyota mls 0.5mm gasket so I will save money there aswell. I will have to run super instead of standard fuel.I can keep my current injectors that have just been rebuilt. What do you think or will a high compression engine wont perform as good as I think? Quote Link to post Share on other sites
5e colin Posted September 13, 2014 Share Posted September 13, 2014 you wont be able to boost 1.4bar of boost on the stock pistons carl safest part is 4efte pistons on the 5efhe rods and stick to 1.2bar on a tdo5 this will net u 250/270 bhp if set up good just my 2c you need bigger injecters on both setups Quote Link to post Share on other sites
FMuscle Posted September 13, 2014 Share Posted September 13, 2014 I'm doing FTE pistons on 1st gen 5E rods. I'm not following that turbo bs, my supercharger should only push about 0.7 bar when I switch it on. Quote Link to post Share on other sites
karl. Posted September 13, 2014 Author Share Posted September 13, 2014 you wont be able to boost 1.4bar of boost on the stock pistons carlsafest part is 4efte pistons on the 5efhe rods and stick to 1.2bar on a tdo5 this will net u 250/270 bhp if set up goodjust my 2c you need bigger injecters on both setups Colin, I will be forging the engine so pistons, rods etc won't be a problem. I have 375cc injectors so I'm hoping these will be enough to run up to 1.2/4 bar.What do you think? Sadly a super charger won't be a possibility Quote Link to post Share on other sites
5e colin Posted September 13, 2014 Share Posted September 13, 2014 370cc is to small for 22psi i would say 440cc injectors carl and go tdo5 !!! tdo4 will drop of at the top on a 5e Quote Link to post Share on other sites
jayc-glanza17 Posted September 13, 2014 Share Posted September 13, 2014 Low compression set up matey.. Agree with colin though karl.. Quote Link to post Share on other sites
neilsmith Posted September 13, 2014 Share Posted September 13, 2014 I would defo say high compression as I have had a 5e highcomp with td04 at 1 bar and made 275bhp easily and very reliable. Also very very lively off boost and spools the turbo up sooner, sounds better aswell in imo. Cheers Neil Quote Link to post Share on other sites
AdamB Posted September 13, 2014 Share Posted September 13, 2014 High compression without a doubt, but how high you thinking? I think the max you can probably get will be around the 9.5:1 mark, but you would need to use flat top pistons to get that which aren't ideal for a turbo motor. Quote Link to post Share on other sites
morgey Posted September 14, 2014 Share Posted September 14, 2014 Seems so strange seeing high comp being classed as 9.5:1 i know for a turbo motor it is but being an n/a guy high comp doesnt really start till 10+:1 imoPeople have turbo'd a stock 4age 20v upto 300hp and they run 11:1 with the most pathetic rods in the world. Id imagine an incredibly retarded and rich map to get there but needless to say it has been done. Not that this really matters to the op in any way though haha Quote Link to post Share on other sites
daniel_g Posted September 14, 2014 Share Posted September 14, 2014 I'm running a turbo'd Gen1 4EFE engine which has a C.R of 9.6:1 Quote Link to post Share on other sites
karl. Posted September 14, 2014 Author Share Posted September 14, 2014 (edited) 370cc is to small for 22psi i would say 440cc injectors carland go tdo5 !!! tdo4 will drop of at the top on a 5eWell if it comes to it they wouldn't be too hard to upgrade then.I would defo say high compression as I have had a 5e highcomp with td04 at 1 bar and made 275bhp easily and very reliable. Also very very lively off boost and spools the turbo up sooner, sounds better aswell in imo. Cheers NeilSee that's my idea of a well setup car there, quick spooling and plenty of power instead of a lot of power up top.High compression without a doubt, but how high you thinking? I think the max you can probably get will be around the 9.5:1 mark, but you would need to use flat top pistons to get that which aren't ideal for a turbo motor.I'm not actually too sure, I was just thinking about decking the block and head and a thin head gasket but I also have to worry about the valves touching the pistons. Edited September 14, 2014 by karl. Quote Link to post Share on other sites
AdamB Posted September 14, 2014 Share Posted September 14, 2014 (edited) You say you will be using forged pistons, what ones? Like I said flat tops aren't ideal for a turbo motor because they retard the flame front. Using a piston with a dish, even though it decreases the CR slightly will provide better low speed running conditions. If you were going to deck the block and skim the head it will need to be blueprinted and use some play doh or similar moulding device to measure your piston to valve clearance, then you can determine how much you can skim off the surfaces without the valves kissing the pistons. Personally I would just go with Wiseco dished pistons and a 0.6-1mm headgasket. The extra torque you get from the 5E you wouldn't even notice a great difference in increasing the CR. Edited September 14, 2014 by AdamB Quote Link to post Share on other sites
karl. Posted October 31, 2014 Author Share Posted October 31, 2014 So I have finally decided on a spec for the engine.It will running 10cc wiesco dished pistons along with a 0.5mm head gasket.This will leave it with a pretty average compression ratio.The biggest factor is I will be running high lift cams along with this. Does this mean I can go for a higher compression ratio as there will be a slight overlap with 265 degree cams? Do you suggest getting the block and head skimmed to increase to ratio to around 9:1 - 9.5:1? Quote Link to post Share on other sites
ramses Posted October 31, 2014 Share Posted October 31, 2014 (edited) I am not a fan to skim the head to get the target compression.4efte or 5e are prone to overheat and more on a Seo...i am not also a td05 fan. The only td05 i like come from greddy as the td05 14b or t517Z .As i said i prefer a vf35 on a high compression engine or a good garrett gt ball bearing. Remember the set up is not only the key ,the key is a good tune. I have ran on a gt2860 with my old 5efHe stock engine for 4 years on a greddy blue at 1.2b... Edited October 31, 2014 by ramses Quote Link to post Share on other sites
karl. Posted October 31, 2014 Author Share Posted October 31, 2014 Would you rather deck the block to meet compression then? There isnt really any other way to do it, from what I can tell flat top pistons arn't ideal either. So the only way to raise compression is skimming. Tuning wont be a problem either and I will most likely stick with a td04 then maybe a Wepr Billet Td04. Quote Link to post Share on other sites
AdamB Posted October 31, 2014 Share Posted October 31, 2014 (edited) I would rather skim the head than deck the block. The problem is with decking the block if you have piston protusion out past the block you really have to start taking into account material elasticity and how much the pistons and rods will grow at high revs. Theoretically yes with wilder cams you can increase the compression ratio but like I said before you won't really notice a performance increase from such a small raise in the CR. Personally I wouldn't use those spec cams as they aren't ideal for a road turbo motor. There's nothing wrong with the OEM spec cams. Edited October 31, 2014 by AdamB Quote Link to post Share on other sites
Phil Posted October 31, 2014 Share Posted October 31, 2014 (edited) I would rather skim the head than deck the block. The problem is with decking the block if you have piston protusion out past the block you really have to start taking into account material elasticity and how much the pistons and rods will grow at high revs. Theoretically yes with wilder cams you can increase the compression ratio but like I said before you won't really notice a performance increase from such a small raise in the CR. Personally I wouldn't use those spec cams as they aren't ideal for a road turbo motor. There's nothing wrong with the OEM spec cams. honestly the 265degree cams transform the car. maybe its not everyones cup of tea, but the engine has less engine braking, and more top end grunt. i enjoyed driving my old gt with cams, alot more than without, engine ran free'er rev'd harder mid to top. i know that a with a td05 18g they put all the power way up there and no i dont think that is ideal for the road. But with a reasonable sized turbo td04 or td05 14b as ramses mentioned, the cams compliment them great, makes power right to the redline and get pickup after 3k without losing the kick in the pants top end. but then Adam that maybe goes against the theory of what feels fast isnt always the fastest, but big cams in a 4e head (stock cumbustion chamber and ported polish head) and decent turbo is a fantastic road starlet. probably an even better track starlet The lads round me have had everything, from ct9 guru (Jay) to spuddy. and cams are fantastic on these cars even with a ct9 they work great. (extra 10hp 20lb.ft with a stock ct9) Phil Edited October 31, 2014 by Phil Quote Link to post Share on other sites
AdamB Posted October 31, 2014 Share Posted October 31, 2014 (edited) It's just the duration that's wrong for me, 265 is a drag spec cam. For road going and circuit use 225-245 degrees is ideal with 8.8-9.2mm lift. Of course I would expect more top end power, but you also lose a lot of low down and mid range power because of it, like I say for a road going engine it seems a bit much for me unless you have variable valve timing but that's a whole different ball game and not related to Starlets and the E series in particular. Besides running cams on an E series to me is the wrong way to do it because its not the cams that are the weak link as I've previously mentioned to you, its the valves for me and getting cams is just covering up an underlying problem (not necessarily a problem but a weak link) without considering other factors that won't take away engine performance from one area or another. The bonus with cams is they are a "drop in" item and require nothing more than removing and refitting (except the attention to detail to time them up correctly), where as other things may require machining and this ends up having an increased turn around time to get the car back. Edited October 31, 2014 by AdamB Quote Link to post Share on other sites
Phil Posted October 31, 2014 Share Posted October 31, 2014 Haha exactly and the exhaust valves are even more hassle than I had anticipated with shrouding proximity issues.Will see how I get on without valves. Might get abit of work done valve guide seat etcPhil Quote Link to post Share on other sites
AdamB Posted October 31, 2014 Share Posted October 31, 2014 The problem is no matter which way you look at it and whatever you do to the cylinder head, the valve is still going to be the same size.One of the first things I do when looking at designing engine components is look at the valve sizes, if their not suitable for the goal I want to achieve then it's the first thing that gets changed. Quote Link to post Share on other sites
5e colin Posted October 31, 2014 Share Posted October 31, 2014 ^^^^ problem solved guys 1 of our traders should come up for an adaptor plate to fit the tegr head ha ha Quote Link to post Share on other sites
karl. Posted October 31, 2014 Author Share Posted October 31, 2014 Well either way all I'm looking is something responsive and pulls the whole way to the red line. I would rather have a car that's 280bhp and responsive compared to something that's 380 and a saxo can pull away from before it gets going. This is why I'm thinkin a high comp 5e with td04 with cams sounds great. Quote Link to post Share on other sites
5e colin Posted October 31, 2014 Share Posted October 31, 2014 you see carl thats only because your in the wrong gear :p i have a oem lsd box and laggy isnt a problem attal with the closer gears Quote Link to post Share on other sites
AdamB Posted October 31, 2014 Share Posted October 31, 2014 Well either way all I'm looking is something responsive and pulls the whole way to the red line. I would rather have a car that's 280bhp and responsive compared to something that's 380 and a saxo can pull away from before it gets going.This is why I'm thinkin a high comp 5e with td04 with cams sounds great. All you need is a turbo that's operating in its efficiency area, don't need any other trick shit that's just a waste of money. Quote Link to post Share on other sites
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