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Is forging bad?


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Hi,

I see quite a few forged engines with big specs being sold after very few miles being put on them (2000-3000 miles). Is there a reason for this? 

Thank you in advance! 

Edited by Goldie
Question answered!
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7 hours ago, akyakapotter said:

No it's not bad if you keep up on the servicing. I serviced mine every 3k oil and filter. Unfortunately this time round I found metal in the oil not bad for a 9 year old forged lump that has had its head kicked in every time ive used it. 

9 years is brilliant, where did you have the work done? 

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Well said. I work in the aero space industry and quality control is every 1000 item with in 1 batch of material. 

This includes stress and impurity tests. 

For a production line motor vehicle it's every 100,000 item out of multiple different batches of materials from different sources. This is the reason part serial numbers are so important for recalled items. So yeh Luck of the draw stuff when you start quoting power figures over 100% on stock. It's this simple. The evidence is threw out this site. 

Edited by Sam44
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Pretty much as soon as I'd created this post I'd gained my answer, some people get lucky and some people don't, no matter how you drive your car (sorry to hear about yours callum122). 

I'm currently in the market to buy a glanza but feel steering clear of a forged might be a better option then, reckon a well looked after Td04 or 05 would do just fine, and if I wanted to take that risk down the line it's completely on my terms. 

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14 hours ago, Goldie said:

Pretty much as soon as I'd created this post I'd gained my answer, some people get lucky and some people don't, no matter how you drive your car (sorry to hear about yours callum122). 

I'm currently in the market to buy a glanza but feel steering clear of a forged might be a better option then, reckon a well looked after Td04 or 05 would do just fine, and if I wanted to take that risk down the line it's completely on my terms. 

With all due respect a TD04/5 on a stock engine is probably the biggest risk (especially buying second hand).

It's quite common (from builds on this and other sites) that adding a TD04 @ 1bar for 220bhp often ends in head gasket failure. Bit of a crap shoot as to how long it lasts. Often influenced by the tune / maintenance / engine health or supporting component failure. Then the "while I've got it apart" rule kicks in and might as well forge the engine.

Some are then happy to use the forged components as a way of increasing reliability and stick to the 1bar and 220bhp result and with a well built, properly maintained and safely tuned engine they last for a respectable amount of time. Others are using the forged components to increase the power capability and have to accept a much reduced service life of the engine. Quite often multiple maps can be used on a daily driver, low boost running nearly all the time and high power map for special occasions.

I sometimes wonder if there is also a bit of "be careful what you wish for" involved in some of these recently built then up for sale cars? 300+bhp through the front wheels of a small, light 25 year old hatch back was perhaps a bit of an animal and no longer fun to drive? 

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18 minutes ago, Claymore said:

With all due respect a TD04/5 on a stock engine is probably the biggest risk (especially buying second hand).

It's quite common (from builds on this and other sites) that adding a TD04 @ 1bar for 220bhp often ends in head gasket failure. Bit of a crap shoot as to how long it lasts. Often influenced by the tune / maintenance / engine health or supporting component failure. Then the "while I've got it apart" rule kicks in and might as well forge the engine.

Some are then happy to use the forged components as a way of increasing reliability and stick to the 1bar and 220bhp result and with a well built, properly maintained and safely tuned engine they last for a respectable amount of time. Others are using the forged components to increase the power capability and have to accept a much reduced service life of the engine. Quite often multiple maps can be used on a daily driver, low boost running nearly all the time and high power map for special occasions.

I sometimes wonder if there is also a bit of "be careful what you wish for" involved in some of these recently built then up for sale cars? 300+bhp through the front wheels of a small, light 25 year old hatch back was perhaps a bit of an animal and no longer fun to drive? 

I appreciate your thoughts on this as wasn't aware of the Td04 head gasket issues (please excuse my ignorance).

I did wonder if the 300+bhp monsters offen created have almost gone too far and as much as its awesome initially the novelty runs dry and so owners part with them (going back to my first query of parting with a car quickly after spending so much creating). I had in mind the reason people seen the Civic Type-R as so much fun was because although it's not massively powerful it could always be driven on the edge, which is what hot hatches are all about in my opinion. 

Think I need to do some research as to what's a reliable modified starlet setup (obviously all potentially having their flaws), any opinions would be greatly appreciated! 

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Spot on

a tdo4l on low boost provides really good power and fuel economy (160hp) reliable.

The supporting mods are the most important thing cutting corners and rushing the build leads to problems and wasted time and resources. 

High hp cars are not for the road, I'm guessing this is why they sell up, there more for bragging rights or serious racers. 

There is definitely a way to tune these using mostly Toyota parts on a stock engine, and have a very capable street level setup. 

It's very hard not to get carried away.  

 

Edited by Sam44
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1 hour ago, Goldie said:

I appreciate your thoughts on this as wasn't aware of the Td04 head gasket issues (please excuse my ignorance).

No excuses required my friend, welcome to the sight. :thumbsup:

1 hour ago, Goldie said:

I did wonder if the 300+bhp monsters offen created have almost gone too far and as much as its awesome initially the novelty runs dry and so owners part with them (going back to my first query of parting with a car quickly after spending so much creating). I had in mind the reason people seen the Civic Type-R as so much fun was because although it's not massively powerful it could always be driven on the edge, which is what hot hatches are all about in my opinion. 

Personally I have always had the same outlook for street cars, I'd rather have less power and be able to use all of it, all the time than too much power and never be able to use it all. 200bhp per ton is plenty for the street.

1 hour ago, Goldie said:

Think I need to do some research as to what's a reliable modified starlet setup (obviously all potentially having their flaws), any opinions would be greatly appreciated! 

My advice would be to find the least modified, best maintained car you can afford. Decide on the intended purpose and power goals. Service and replace all key supporting components (upgrading were necessary i.e. fuel pump, spark plugs).

Tuning developments are well respected in the Starlet scene and their website has stage 1 and 2 component lists for stock engines (the website is a bit out of date, don't buy Jperformance stuff as there have been rumours they've shut down.). These components pretty much outline the tried and tested modifications for up to 180hp (which in my opinion would be plenty).

Tubular exhaust manifold, decat downpipe, cat back exhaust system, front mount intercooler, HKS adjustable actuator, heat range 7 spark plugs, 255 lph walbro fuel pump, piggy back ecu (with map sensor). Wideband O2 gauge and boost gauge. Method of controlling boost (in the piggy back or separate controller). Good mapping from an experienced tuner should see a reliable 170bhp ish and be fun to drive without being unruly or trying to kill your wallet!

After this your heading into forging, big turbos and £1000's of pounds spent.

Other opinions are available. :drinks:

Edited by Claymore
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Couldnt have said it better myself. 

Tunning developments are the guys with the know how, and years of experience.

From my side I'd say a bigger turbo on low boost is better/safer than a smaller turbo on high boost at the same hp. Remembering the supporting mods which I'd definitely throw a set of ACL bigend shells in the list (high load bearings).

Examples: ct9 against the tdo4l

Edited by Sam44
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6 minutes ago, Sam44 said:

Could have said it better myself. 

Tunning developments are the guys with the know how, and years of experience.

From my side I'd say a bigger turbo on low boost is better/safer than a smaller turbo on high boost at the same hp. Remembering the supporting mods

Examples: ct9 against the tdo4l

Agree on the bigger turbo as far as efficiencies go. Or maybe the TF035HM 6cm housing would be somewhere in between.

Wouldn't want to run a CT9 at too high of a boost level due to boost creep, excess charge temps. and probably end up well off the compressor map. Should be fine under 1 bar, maximising the use of the parts Toyota gave you. Again, just my opinion.

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  • 1 month later...

Can I just add that chasing big bhp figures is just an ego extension...my starlet was running 340ish bhp at one point and although its very fun to give it a burst every now and then, you can't help but wonder when it will go bang. (It is a monstrous feat for any 1.3 engine to reliably put out nearly 3x the factory intended power levels). My new build I'm aiming for a very reliable 220 - 250 with a hybrid turbo adapted from a 595 abarth with hardly any lag. I think this was the sweet spot when building my last engine and in hindsight should have left it around that figure. It was just as fun and on the streets there's very little opportunities to really use the car to its full potential.

Don't be an idiot and chase the figures, you can have as much fun with less power (and less expense) 😀

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Very well said.

I've turned mine down abit from 250ish hp to around 220hp as my 0 to 60mph times started to fall away with the control factor also impacted with the hard hit/surge in power.  At 220hp the car is crazy capable plus it will last along time. Mine is not forged, I don't think needs to be. 

I have no doubt that the 100 to 140mph times were better at 250hp but the simple fact I'm not aiming or wanting to take the starlet over 100mph on the street and 120mph on track.

I have a gtx17 here for my 5e build that's going on big cams. Zero lag full rpm of pull.  

 

 

Edited by Sam44
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I've now found myself a Glanza, fully forged with a Td04 hybrid running 230hp and can quite happily say that's plenty for me. It's currently .9 bar and is capable of 1.6 however I can't see myself wanting to turn it up for quite some time. 

I'm very glad I didn't buy one that's sitting at 300+ hp, the anxiety that I'd bought a time bomb would be too much and previously said there wouldn't be the road to use it. 

Thanks again for all your help and opinions, they were definitely a deciding factor when buying my car 

Edited by Goldie
Got my 6's and 9's mixed up! 😉
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1 hour ago, Goldie said:

I've now found myself a Glanza, fully forged with a Td04 hybrid running 230hp and can quite happily say that's plenty for me. It's currently .6 bar and is capable of 1.6 however I can't see myself wanting to turn it up for quite some time. 

I'm very glad I didn't buy one that's sitting at 300+ hp, the anxiety that I'd bought a time bomb would be too much and previously said there wouldn't be the road to use it. 

Thanks again for all your help and opinions, they were definitely a deciding factor when buying my car 

Build thread?😉

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As many stated the stock pistons are very capable..

Even on a budget with the right piston ring gap you can get away with crazy boost levels and stock internals. Engine management is key in engine life and how hard you push the internals at lower engine speeds... Stock internals don't like shock torque loads.

Tune right and you will be happy with 200+ bhp all day and be able to put the power on the road.

Forged internals are great when build right ( tolerance wise ) and for the right purpose .

 

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