Is Forging Worth it in 2024?

[Djaniero]

As above lads, what are you thoughts on forging a 4e these days?

I have spare 4e block and have the financial means to start buying parts to forge my GT. I’m not planning anything major just a weekend toy with 280-300bhp.
However, I have noticed a hike in price for 4e parts compared to when I did my last rebuild….showing my age lol. So it’s making me think shall I just be content and enjoy my car as it is, with a reliable 230bhp /TD04 setup , with supporting mods etc, or forge it and go for a stand-alone ecu setup?
For what it’s worth, I am pretty bored with 230bhp ans wanted more hence why I bought the spare block to forge in the first place.
I’ve spoken to others that have forged and said they did think it was worth it for the increase in performance.
Thanks for any thoughts

 

[SKINY]

It will future proof it for when you do decide for more power.
I'm going to do mine, gummy rings but it would be rude not to while it's In bits, no major power plans just the tf035 kit but then I'd feel better about spanking it and it not going titties up

 

[dac69er]

Imo I wouldn't waste my money doing it again.

With more power comes a smaller power band and less driveability. It's fun for a while, but it does get old pretty fast.

If I was to do it again, I would probably go 5e and spend decent money on a good turbo.
The improvements wouldn't be huge over a 4e and a hybrid td04, but it would ensure it is more driveable with some added top end power.

Not that it is anywhere near as simple, but a kswap is probably a better way to go realistically, just costs more of course.

I think a stock rebuild and about 220-230bhp is the best compromise for a 4e. Much more and you start making it worse to drive on the road.

 

[Djaniero]

Thanks for the responses.

@dac69er the plan initially was to go 5e, but the seller kept messing me around hence why I got a spare 4e block in the end.

230bhp has been ok, but I’m bored now and want more. K20 would be immense but again more expensive.

Are you still unhappy with your build after forging?

 

[gorganl2000]

i've thought about it since i saw the post yesterday...and i'm still on the fence as i basically agree with both skinny and dac69er

i went from an oem 4efte to oem parts built 5efte in 2007/2008 and vowed never to go back to a 4efte...the drivability was vastly improved (ct9, td04l, td05/vf series)

i then went from oem parts built 5efte to forged 5efte in 2017...only for the added reliability (piece of mind) and i had a spare 5efhe which i used for the forge build, so my car was never really off of the road except during the engine swap....so in effect my original oem parts 5efte is still there in perfect shape sitting in storage

a big part of an engine life's is the tune, maintenance and sensible driving

now power wise, i'd agree that over 200/250bhp, whether 4e or 5e, in these relatively light weight FWD cars tends to be a waste (wheel spin, torque steer, etc.) for road driving and may lead to the dreaded gearbox issues

the k20 is a lovely engine, but the swap is relatively expensive in comparison to forging a 4e/5e,,, i'm not sure its worth if unless its your dream and you have plenty funds to throw at it to do it properly

even then, the k20 is 200/220bhp in oem trim...which is right back to where you are now

 

[H_D]

I Worry about my gearbox more than the engine. i will end up doing an engine swap at some point as gearboxes are getting much harder to come by and more parts for the gearbox are starting to become discontinued.

 

[Djaniero]

i've thought about it since i saw the post yesterday...and i'm still on the fence as i basically agree with both skinny and dac69er

i went from an oem 4efte to oem parts built 5efte in 2007/2008 and vowed never to go back to a 4efte...the drivability was vastly improved (ct9, td04l, td05/vf series)

i then went from oem parts built 5efte to forged 5efte in 2017...only for the added reliability (piece of mind) and i had a spare 5efhe which i used for the forge build, so my car was never really off of the road except during the engine swap....so in effect my original oem parts 5efte is still there in perfect shape sitting in storage

a big part of an engine life's is the tune, maintenance and sensible driving

now power wise, i'd agree that over 200/250bhp, whether 4e or 5e, in these relatively light weight FWD cars tends to be a waste (wheel spin, torque steer, etc.) for road driving and may lead to the dreaded gearbox issues

the k20 is a lovely engine, but the swap is relatively expensive in comparison to forging a 4e/5e,,, i'm not sure its worth if unless its your dream and you have plenty funds to throw at it to do it properly

even then, the k20 is 200/220bhp in oem trim...which is right back to where you are now

Hail Gorgan,

I am still sat on the fence about it in all honesty.
I would ideally love to do a forged 5e build, however they have become a rarity here now in the UK...where by people who do have them want crazy cash to buy them.
This is why I got my hands on a spare 4e block instead.
The other option I thought was to fit a set of arp head bolts and see how far my tuner could reliably push it on stock internals. However I think if I'm going to that extent, I may as well forge the bottom end while the engine is apart.

 

[gorganl2000]

I Worry about my gearbox more than the engine. i will end up doing an engine swap at some point as gearboxes are getting much harder to come by and more parts for the gearbox are starting to become discontinued.

i'm on a similar thought path...i was lucky enough to get a very good condition ep91 gearbox a few years ago as a replacement for my ep82 gearbox which had 2nd gear synchro issues.....since then, even on a spirited drive, i'm mindful of my shifts, especially 1st to 2nd and 2nd to 3rd....i typically purposely let the revs drop out of the sweet spot to get easier gear engagements and i avoid hard launches from a standstill (relying on rolling starts before giving it the beans)

more parts are being discontinued in general for these cars...so scarcity, import duties and rising selling prices have to be considered.

 

[daniel_g]

No matter which way you look at it, its not exactly cheap.

I've been dragging on builds for years.

Is it all worth it in the end?

Starlets seem to finally be worth a few quid so its not a total waste of time.

I'd still say go for it, but just keep in mind one thing leads to another and before you know it you'll keep having to replace parts that might be the next point of failure.

Injectors and spark plugs have caused me forged engine failures. Once a chipped valve, melted wiseco pistons, broke a crank cap too. Blew a head gasket once aswell. They aren't bullet proof by any means.

 

[gorganl2000]

Hail Gorgan,

I am still sat on the fence about it in all honesty.
I would ideally love to do a forged 5e build, however they have become a rarity here now in the UK...where by people who do have them want crazy cash to buy them.
This is why I got my hands on a spare 4e block instead.
The other option I thought was to fit a set of arp head bolts and see how far my tuner could reliably push it on stock internals. However I think if I'm going to that extent, I may as well forge the bottom end while the engine is apart.

to get a 5e...you could investigate buying a whole donor car if it can be obtained cheaply---paseo, cynos, sera, tercel ...its just the engine you want, so the shell could be in a miserable state, making it cheap to buy

it may be cheaper than just purchasing a 5e engine via ebay, import from japan, breakers.

 

[gorganl2000]

No matter which way you look at it, its not exactly cheap.

I've been dragging on builds for years.

Is it all worth it in the end?

Starlets seem to finally be worth a few quid so its not a total waste of time.

I'd still say go for it, but just keep in mind one thing leads to another and before you know it you'll keep having to replace parts that might be the next point of failure.

Injectors and spark plugs have caused me forged engine failures. Once a chipped valve, melted wiseco pistons, broke a crank cap too. Blew a head gasket once aswell. They aren't bullet proof by any means.

that's another decent point...sometimes people forge engines and expect that they will last forever regardless of the treatment....that's an expensive misconception

 

[Djaniero]

I Worry about my gearbox more than the engine. i will end up doing an engine swap at some point as gearboxes are getting much harder to come by and more parts for the gearbox are starting to become discontinued.

Valid point tbh. What power are you running at at the moment?

 

[Djaniero]

No matter which way you look at it, its not exactly cheap.

I've been dragging on builds for years.

Is it all worth it in the end?

Starlets seem to finally be worth a few quid so its not a total waste of time.

I'd still say go for it, but just keep in mind one thing leads to another and before you know it you'll keep having to replace parts that might be the next point of failure.

Injectors and spark plugs have caused me forged engine failures. Once a chipped valve, melted wiseco pistons, broke a crank cap too. Blew a head gasket once aswell. They aren't bullet proof by any means.

Agreed man.

I must be getting old as in my younger years I wouldn't think twice about spending the endless amounts of cahs on my jap mods.

Oh wow.... sounds like you've had a nightmare over the years.
Did you build the engine yourself when you had these failures?

 

[daniel_g]

Agreed man.

I must be getting old as in my younger years I wouldn't think twice about spending the endless amounts of cahs on my jap mods.

Oh wow.... sounds like you've had a nightmare over the years.
Did you build the engine yourself when you had these failures?

Thats only the forged engine failures! Its been a mixture of bad luck and blatant disregard for mechanical sympathy on my part.

The engines were built professionally. At the time the spec of the engine / parts was more than the 'stage 3' engines that companies were selling. So it wasn't a matter of budget or anything.

Point I'm trying to make is forged builds can also have problems, especially if you are pushing it. But don't be put off.

Also scrap the TD04 turbo and move onto a Garrett type turbo, the Pulsar copies are supposed to be good. GTX2860 will see you over 300 with ease with similar spool times.

 

[Djaniero]

to get a 5e...you could investigate buying a whole donor car if it can be obtained cheaply---paseo, cynos, sera, tercel ...its just the engine you want, so the shell could be in a miserable state, making it cheap to buy

it may be cheaper than just purchasing a 5e engine via ebay, import from japan, breakers.

Agreed, but again they do not come up for sale very often here in the Uk unfortunately

 

[Djaniero]

Thats only the forged engine failures! Its been a mixture of bad luck and blatant disregard for mechanical sympathy on my part.

The engines were built professionally. At the time the spec of the engine / parts was more than the 'stage 3' engines that companies were selling. So it wasn't a matter of budget or anything.

Point I'm trying to make is forged builds can also have problems, especially if you are pushing it. But don't be put off.

Also scrap the TD04 turbo and move onto a Garrett type turbo, the Pulsar copies are supposed to be good. GTX2860 will see you over 300 with ease with similar spool times.

Oh really ? I guess you live and learn hey.

sounds like you invested in some proper bits along the way for these builds too.

I have a td04 and a vf28 which I was planning to use on the forged 4e…old skool turbo’d now…I know. I have often thought about getting a garrett type turbo but that would mean changing my manifold.

 

[H_D]

Valid point tbh. What power are you running at at the moment?

im only running 230bhp at the moment on low boost and my gearbox is fine. I broke my last gearbox when i was running full boost at 271bhp. In the grand scheme of things I want to be running 300-350bhp safely and not worry about breaking gearboxes. I want to drive it like i stole it lol

 

[H_D]

i'm on a similar thought path...i was lucky enough to get a very good condition ep91 gearbox a few years ago as a replacement for my ep82 gearbox which had 2nd gear synchro issues.....since then, even on a spirited drive, i'm mindful of my shifts, especially 1st to 2nd and 2nd to 3rd....i typically purposely let the revs drop out of the sweet spot to get easier gear engagements and i avoid hard launches from a standstill (relying on rolling starts before giving it the beans)

more parts are being discontinued in general for these cars...so scarcity, import duties and rising selling prices have to be considered.

this takes away drivability IMO. I want to be able to drive spiritedly and not worry about breaking a gearbox. its always in the back of mind (i wonder how much more the box will take before it dies)

 

[daniel_g]

Oh really ? I guess you live and learn hey.

sounds like you invested in some proper bits along the way for these builds too.

I have a td04 and a vf28 which I was planning to use on the forged 4e…old skool turbo’d now…I know. I have often thought about getting a garrett type turbo but that would mean changing my manifold.

You can actually get Garrett style turbine housings for TD/VF fitment.

 

[Djaniero]

im only running 230bhp at the moment on low boost and my gearbox is fine. I broke my last gearbox when i was running full boost at 271bhp. In the grand scheme of things I want to be running 300-350bhp safely and not worry about breaking gearboxes. I want to drive it like i stole it lol

I can imagine that must be frustrating if you wonna drive it like you stole it. Was it 3rd gear that went in your first gearbox?