The new 7AGE build contributions welcomed

[Bigmanbandy]

Hi, I did a lot of research and I want to continue the build. I was told that the con rods are prone to failure and that the civic B18 rods can be used. The big bore end is the same size at 48mm, the length of the 7A rod is 132.5mm and the small pin bore is 20mm. The B18 rod is 137.9982mm and the small pin bore is 21mm. Because of the wrist pin size difference I may have to use either the b16 pistons or b18 pistons. I have not done much reading to determine which would work best, but I do believe that the B18 is of a lower compression ratio and since the civic rod measures a whole 5.5mm longer I may have to use a thicker head gasket and I would have to use the silver top head since the combustion area is deeper. I believe that a flat top piston might be best to avoid severe head damage in the event that there is timing belt failure. My question is in your opinion do you think that the con rod is too long? and which piston should I go with?


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did some more reading and the B16 and B18 uses the same wrist pin size of 21mm, so If I use the civic piston, it would be a direct fit, but I do not know the overall height it would end up over the block height or still under, I cant say. If I use the Toyota piston I have to use the civic wrist pin and open the ends of the piston to accommodate the civic wrist pin, which I do not have access to.

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Will take pics of the 4AGE 20v piston on a 7AFE con rod. Perfect fit. The block have to be cleaned out to about 20 thou so that's why I cant use the std piston. The aim is to make it a high comp N/A engine.

[Bigmanbandy]

Hopefully this will be installed today!

[Bigmanbandy]

I decided to not go with the Honda rods. It was too iffy, and I read somewhere that the 7AFE rods are good up to 190 to 200 hp. I also decided to go with oversized pistons and not reline the block. New con and main bearings.

[Bigmanbandy]

Picked up the engine block from the machine shop Thursday. The pistons I bought online was delivered to the wrong address. So I am expecting a refund soon. Dropped off the parts by the mechanic. He inspected the block and said that it was cleaned up to his satisfaction and that it could be used with the pistons that I have fitted on the 7A rods. All I need is 10 thou rings and he would file them to fit.
Does anyone knows where I can get these rings to buy and how much? I will have my new main and on rod bearings by Friday God spare so I kinda need them in a rush.

[Bigmanbandy]

Also I would like to know which head would give me the best performance, and since I have both the silver and black top heads, is just a matter of which is best. I have witnessed several debates on which head is better. Even on Bill Sherwood 4age website he prefers the squish area of the silvertop head. I would like to know your opinions of which head is best suited for this particular setup of the silvertop pistons on stock 7a con rods, with the option of supercharging if it dosent pull like what I would like.

[Bigmanbandy]

Got my refund for the pistons, bought rings locally. I spent two days searching for rings. I ended up buying standard and ten thou rings.

[TESTED performance]

dude wtf you wasting time over stupid crap like squish area for? Toyota commissioned yamaha to design both platforms. Yamaha made the silver first and then they made improvements and released the black. Any changes that weren't made to improve performance were surely still worth having whether from a reliability standpoint or otherwise. Use the blacktop as your starting point and stop fussing too much over fine details. In my experience it is just a distraction from progress and to be honest with you the bigger picture is much simpler. All you needed to do was get a good management system some upgrade cams lower compression pistons and higher flowing injectors. I know you want to do it the right way but you have to understand that these engines were pretty well developed to begin with and agonizing over upgrade specs isn't going to net you anything in reality in terms of dyno measured horse power or road usable power. Button up the whole mess properly then get an outstanding tuner (good luck finding one) and you will be surprised how shockingly violent your current project will feel. If you plan on competing in an environment where every tenth of a second on your lap or quartermile time is critical then by all means disregard my previous advice.

[corolladude]

dread!! jus buy ah frigging 3sgte !!!!

[Bigmanbandy]

Sounds good, but I dun buy this already and I dont wanta go turbo. At least not as yet any way.

[Bigmanbandy]

In my experience it is just a distraction from progress and to be honest with you the bigger picture is much simpler. All you needed to do was get a good management system some upgrade cams lower compression pistons and higher flowing injectors. I know you want to do it the right way but you have to understand that these engines were pretty well developed to begin with and agonizing over upgrade specs isn't going to net you anything in reality in terms of dyno measured horse power or road usable power. Button up the whole mess properly then get an outstanding tuner (good luck finding one) and you will be surprised how shockingly violent your current project will feel. If you plan on competing in an environment where every tenth of a second on your lap or quartermile time is critical then by all means disregard my previous advice.

Is just I am afraid that the build will not last that is all because my mechanic did it once and it didn't last, that's why he was probably a bit hesitant to do it for me. The engine started to knock. I have all the parts in front of me on my work bench, I have a new wright tool certified calibrated torque wrench, I have the repair manual for the 4age black. I do not have the manual for the 7AFE so I do not have the torque specs for the con rods and hence I am a bit hesitant as well.
I will quote my mechanic here and say that what causes failure is not enough oil pressure. So they does doctor the oil pump. Because I have the parts in my hand I can see exactly how they work. The oil pump is equipped with a check valve to dump excess pressure back into the engine, right?? So In doctoring it is there anything like too much oil pressure? I was told that too much oil pressure can burst the oil filter??? Ever heard of this? As well as do I install the oil squirter's from a a 4age? It was said to me that it would only rob me of oil pressure.

[Hook]

I have a bad oil pump that I opened up. If I get time by weekend, I'll show you how it works and what they do to tweak it to get more pressure.

There's a pressure release valve that tops out around 80psi or so, even if you swing it close to 8000rpm that's your ceiling. What some people do is add a couple flat washers behind the stopper to compress the spring more, so that it's stiff enough to open the pressure release valve at a higher pressure.
It's a trial and error thing really, because it all depends on the health of the spring and how much more you compress it with the thickness of the washers (up to a point of course).

[Bigmanbandy]

Thx hook, but what about the squirters and how much do I torque the con rod nuts to?

[Hook]

*shrugs* what about the oil squirters? Nobody mentioned them until now.

See, I'm not sure what you're doing or where you're heading with this. There are two basic differences between the engines you want to merge - one's a short stroke (77mm), high-revving 1.6L that makes it's power up top and the other is a longer stroke (8?.?mm) 1.8L with decent low end torque but a 6500rpm redline.

But for the same bore, a shorter stroke engine favours high revs, so it's not as simple as slapping a 20V head on a 7A block and using a porsche timing belt. Your 7A crank will take a walk at 7800rpm just when you get up to where your 20V head feels at home.

Rightfully said, the 20V is okay right out the box, but you're taking a mish-mash of parts from other engines to try to re-engineer it. If Toyota/Yamaha wanted a 1.8L 20V they would've done it, likely by increasing the bore to fit wider pistons and bigger valves, not increasing the stroke.

I say don't overthink it. Rebuild your 20V back to stock specs and lean on it with management, nitrous etc. OR rebuild it with forced induction in mind.

[secret_service]

Good advice.... These 7A builds are just not worth it.

To take advantage of the lower than stock RPM limits you will need to have the power band moved lower as well so modified cams and a controller to change the cam cross over RPMs.

Or modify the 7A crank, bearings and rods to REV up to 9000rpm.

Or just forget about all that an get a 4E-FTE which is another Yamaha special order and spend the money on aftermarket parts for it, an maybe a 5E block..... Make more power than your 7A can reliably

[TESTED performance]

OK you already made up your mind to go with the 7A. There is something I think many people don't seem to get when getting the right spec for their project. Power and torque are subjective and depending on what you really want from a project, more equals less and less equals more. Some questions must be answered to gain better perspective and make the right decisions. Is this build going to be fitted to a track car that doesn't even require a license plate? Is it going in a weekend racer that still needs to break time attack or drag race records? Is it going to be a in a project car that isn't a daily driver so downtime is no object. Does it have to be a reliable street car?

Concerning a 7A build here's my thought process. In a lightweight (around 1100kg)front wheel or rear wheel drive car low end torque is usually only going to benefit you when cruising by giving you better fuel consumption. For hard launches and tight bends it will negatively affect traction and god forbid that damp surface conditions prevail. From personal experience 250 wheel horsepower as measured on a chassis dyno is the upper limit of sensible power that a lightweight frontwheel drive turbocharged car can transfer to the road under most conditions. Anything more than that will only be useful in 4th and 5th gear at highway speeds. Depending on how capable your ECU is you can do things like limit boost to correspond with gear selection and engine load so that while your available torque output maxes out at ridiculous numbers (500+) the engine doesn't put it all out unless programmed criteria are met.

It is unfortunate that you do not have the original engine manual for the rebuild but don't give up yet because if you look around you should be able to find someone else who did the rebuild and find out what they did. It may interest you to know that it is unlikely that following the 7A rebuild manual to the letter would land you a reliable platform. Torque as produced by a turbo engine creates significantly high stress on components and this must be taken into consideration and compensated for when switching from the NA to forced induction platform. So as crazy as it sounds you may have better results following OEM specs and guidelines for rebuilding the 3SGTE engine instead of the 7A. I'm not talking clearances here just torque specs for tightening up all fasteners. This is the downside of daring to be different and blazing a different trail. It can sometimes be trial and error. Don't let a failed attempt get you down or discourage you. A knocking engine doesn't mean total engine failure. It can be fixed quite easily in most cases without expensive crankshaft repairs. Maybe you can compare 4AGE clearances vs 4AGZE and let physics and commonsense guide you with how you set your clearances.

Install the 4AGE squirters. Oil pressure reduction is not something to be feared it is something to be understood. The lowering of oil pressure doesn't always indicate a reduction in oil flow. Quite the opposite is usually the case but that's a topic for another time. The point is that as long as there is an adequate supply of oil flowing through your engine a small drop in pressure will not hurt the engine even slightly unless the oil pressure drops below the lowest allowable value as outlined by the manufacturer. Changing the weight of engine the oil you are using can be a quick fix to provide small increases or decreases in oil pressure. Keep in mind though that OIL FLOW beats OIL PRESSURE in almost every instance and therefore what you really want to look out for and eliminate are things that cause unnecessary restrictions. For example using crank bearing clearances that are too tight and using a very thick oil such as a straight 50W will guarantee you a very high and quite comforting reading on an oil pressure gauge at cold startup while in fact there would be almost no oil flowing through the journals and significant damage will be done in a very short time. e.g. knocking.

It is possible to burst the oil filter but it will take significant oil pressure and a low quality filter to accomplish this rare disaster. I have had no luck using perolator filters on high performance engines and although fram filters are designed better they have no place on a high revving high output engine. Many people may tell you that it's all the same but it really isn't. I was looking for an old box before typing this but I can't find one to confirm it so you'll have to check but let me make this very clear... If the 7A block uses the same filter as the 4AGE then pony up the cash and use only ORIGINAL GENUINE toyota filters on your project engine. The people who get fram filters to work on this platform simply never drive these engines hard enough to encounter the problems I did. The fram filters are ok OUTSIDE of the high performance arena. I scrapped down a whole darn car trying to find the source of a horrible back-pressure issue I was having and it was easily resolved by fitting a TRD oil filter. Later I discovered that the OEM filter has very similar flow characteristics and most high performance builds actually use them with no problems.

Now go forth and build thee this monster that shall make thy fellowmen proud.

[Bigmanbandy]

After seeing two engine failures using fram filters on 4age 20 valve engines, I switched to genuine Toyota oil filters on d wifey car even though is a regular 4afe engine. The two engines starved for oil while being pushed hard by their owners. They were by my mechanic and when he picked up the filters and shaked them you could clearly hear the internals separated from the casing. So for my car I switched to perolator filters after realising that fram was generating reliability issues. Now this

I have had no luck using perolator filters on high performance engines and although fram filters are designed better they have no place on a high revving high output engine. .

As for my car it is a daily driver, I started out with an AE80 and when the opportunity arose to upgrade to a 92Gt I took it. The 92 was too slow so I gave away the engine and gearbox until I bought a silvertop engine and lsd box from bicks. I used back my tom's flywheel from the 80. I upgraded the TRD clutch disk to ACT. But it wasn't as fast as the 80 (for obvious reasons). But it had way better handling. I changed the management to blacktop automatic (huge mistake) and I changed to blacktop cams. It now has aeromotive fpr and pump and a free flow exhaust (which still isn't free enough) and imo is now faster than the 80. The reason for the build started out simply because I didnt want any down time. Before my mechanic switched to 3s turbo had his track car with a 7age supercharged. That is the red 80 for those who know it. And up to this day he always say the smaller engines better. But they always use the bottom end stock (7Aa). Based on the fuel that I want to use (super) and based on the rpm I want to climb to in the shortest time, I decided on my own to put in the high comp pistons. I know it will complicate things but if it works I believe that I will be smiling all the way to the bank. Also if I get aftermarket rods I can rev it all the way up.
Also I never thought that my silver top would still be alive cutting a$$ till now. It has serious blow by till the dip stick be sticking out as the turbo cars do when they have blow by.

[TESTED performance]

I got it COMPLETELY wrong then and I apologize. You are doing a normally aspirated 7A/4A build for your daily driver, with no immediate plans of turbo charging, and that changes EVERYTHING.
I would not accept the challenge of a 7AGE NA build for many many manyyyyy reasons. This statement should not discourage you but you should be aware that it is possible to go through this entire process and end up right back where you started in terms of seat of the pants feel.
Here are the top 2 reasons why:

1) COST- You are obviously looking at a low cost rebuild solution and this will effectively rule out upgraded ECU, camshafts, custom high compression pistons, and lightened rods which are vital to at least ensure that torque gains from the increase in displacement are actually detectable away from the dyno.
The REAL reason the 20V blacktop feels so much more lively than the silvertop is because of its holistic approach to improving performance instead of focusing on just a single aspect.
The combined effect of better induction, lighter rods/pistons, increased compression, reworked port geometry, increased valve opening distance and duration, all work together to provide that more lively response of the blacktop. Do you really think if you took a silvertop engine and tuned the air fuel ratio a bit that you can't get the extra 5 horse power of the blacktop? Of course you can but you'd never be able to feel the difference on the road. The main advantage the blacktop has is the engine's response and obviously if you remove the light weight blacktop pistons and rods from the equation there is no way the response/rev characteristic will remain the same using heavier components. Add to that your new increased stroke specification and the piston has to travel further up and down, resulting in even more parasitic losses to the engine's ability to gain revs quickly.
At this point whatever advantage you gained from the larger displacement by way of increases in torque will only help with fuel economy over long distances at steady cruise speeds but at higher RPM with wide open throttle the response will not feel much different from a well maintained 1.6 blacktop. To make matters worse because of the cost factor you're pretty much locked out of the blacktop option since your increased displacement acts as an increase in volumetric efficiency and this cannot be automatically compensated for by the factory ECU from a MAP sensor as most people believe. It will probably feel fantastic on super but that will be as a direct result of creating a permanently lean condition that cannot be corrected by the ECU and it will gladly switch to some failsafe compensation map that either burns way more fuel than usual or it may remain with the existing fuel ratio and retard timing till the engine puts out the same power as a solar powered lawn mower.
Your only hope of getting the best result would now fall squarely on the shoulders of the silver top platform where the air flow sensor can account for the change in volumetric efficiency and aid the ecu in adjusting ignition timing and fuel delivery for safe reliable operation on 92RON petrol.

2) Actual Gains- Just stop for a second and visualize all the headache you have undertaken so far and are about to undertake for the project to be completed. Now ask yourself this... If a bone stock 20V blacktop 1.6 engine will easily output 115 ft lbs of torque with nothing but intake and exhaust modifications, are you comfortable going through everything you're about to for a gain of only 10 more lbft of torque? Yep I said TEN! from past experience even though I have not done the 7AGTE upgrade I can BET you 100 bucks right now that you will not squeeze anymore than about 125 lbft of torque out of this as an NA project, and for me that's a deal breaker right there.

Even though this doesn't help I hope it at least adds perspective.

[xtech]

i believe he also intends to supercharge it

[Bigmanbandy]

The 5 valve head is not very efficient under boost. Have a read.

[Bigmanbandy]

http://forum.9000rpm.co.za/viewtopic.php?id=446

[TESTED performance]

lol Really? when you finish your project let me know. We'll organize a real world comparison between the 5 valve head NA vs Boosted and settle it once and for all.

[Bigmanbandy]

VS boosted 4 valve? yeah I would like to see that.

[Bigmanbandy]

I have run into a stumbling block. The ring clearances are too tight. I have to file the rings and I dont have a filing tool.
http://www.youtube.com/watch?v=pf1rbqliYjk
Anybody know where I can get this rented? To buy it wont make much sense since I may never use it again.

[Bigmanbandy]

Hmmm, so the porsche timing belt boes not work on the 20 valve head. Ouche?
It works on the 16 valve head. To get this to work I need either a really big tensioner pulley or a belt which has 116 teeth.

[new gt]

just to add a little insight,a fellow tuner in asia has done the same 7agze b/t 20v and has figures of 190hp with 140 ft lb of torque at 8300 rpms in ae101 .He still runs stock 7a ecu and only did the internals.All he did was ceramic coat the pistons and rods.This car has been dynoed and is still running .

[TESTED performance]

[Bigmanbandy]

Which timing belt did he use? The 16v timing belt might work but without a tensioner. I dont think that safe?

[corolladude]

Can somebody delete this dotish thread plz .. :/

[Hook]

it bodderin yuh oar bigman?

[TESTED performance]

delete because of what exactly? What makes it dotish?