high compression forged engine

[ash p]

So I have decided to go for a forged 5e tdo4 set up however I see alot of fast road starlets running high compression 5e engines is this achieved only by the pistons and rods used? Also advantages of these engines and what machine work is needed to build one?

[daniel_g]

Would be achieved by piston head surface design & headgasket thickness.

Limits the boost you can run though, but then again it would be 'less lazy' off boost with a higher comp design.

[ash p]

What pistons on the market are high compression? Also do you know anyone who has built one abd the boost limits ect

[StuDoc 72]

Why do you want high comp?

Your set up makes little sense. A high comp engine running td04 doesnt make much sense as like Dan says it limits the boost you can run and technically you can run a td04 on a standard engine up to about 1bar safely.

IMO high comp only makes sense if you are n/a, with a boosted car surely low comp makes more sense.

[H_D]

higher compression is the new way forward my next build will be running slightly higher compression - i didnt go into too much details but its what my engine builder and tuner is recomending.

[ash p]

I got to say I was surprised also but like above high compression engine setups are being recommended who is your engine builder mate^^^^^

[The Toffinator]

My engine is going to be 9.1 Compression... Easily achievable and much more efficient and responsive but as above limits massive boost levels which 8/10 People don't use anyway.

[ash p]

What kind of boost levels are we talking I will at most run 1.5 what setup and boost level will you be running and how will you achieve that compression I.e what spec is your build

[AdamB]

The more important factor is the fuel your going to be using and the engine management system. I for one certainly wouldn't want to be running anything above 8.5:1 on a piggyback. Invest heavily in your engine management system is the best advice I will give for now.

High compression engines are far superior to low compression engines, better fuel economy, better off boost driveability, more power, more torque.

[H_D]

I got to say I was surprised also but like above high compression engine setups are being recommended who is your engine builder mate^^^^^

I get all my parts and engines and mapping done by future motorsports.

Been using them since day 1 as they are very local to me.

[Turk]

Im pretty sure you can also increase the compression by skiming the head or block too. But i do beleive high comp turbos the way forward. I would go higher then 9:1 i think 9.5:1 is ideal for me. But i live in london and its a bit hard to use the power especially with a td04

[AdamB]

I wouldn't go that high on a stock head for sure. 9:1 is ample enough for most people and will still be able to take a whack of boost depending on which turbo you run. The larger the turbo the more efficient its going to be meaning the more power made.

[Turk]

Yh true but the higher the compression the more efficient it will be also. But problem with a large turbo is the time to spool up. So its not as efficient as it would be off boost. Id rather have a car thats efficient off boost. Ie increase compression. Ill also lower the boost slightly to compensate for it. Theres load of info out there on how to calculate what your cylinder pressure is going to be on boost. So just increase compression and lower boost and get the same cylinder pressure. You might have less power. But it will be hell of a drive

[Phil]

Yh true but the higher the compression the more efficient it will be also. But problem with a large turbo is the time to spool up. So its not as efficient as it would be off boost. Id rather have a car thats efficient off boost. Ie increase compression. Ill also lower the boost slightly to compensate for it. Theres load of info out there on how to calculate what your cylinder pressure is going to be on boost. So just increase compression and lower boost and get the same cylinder pressure. You might have less power. But it will be hell of a drive

yeah we found with our last build that we made roughly the same (torque vs boost) but more (hp vs boost)

215 lb/ft @ 1 bar td04

262 hp @ 1 bar td04

Phil

[daniel_g]

Im using a Gen1 FE which has a C.R of 9.6 - 1, i was thinking about running 0.6 bar on the VF12, hopefully it dosent det its tits off.

Suppose i could fire a 1.9mm HG in at a later date.

[Phil]

Im using a Gen1 FE which has a C.R of 9.6 - 1, i was thinking about running 0.6 bar on the VF12, hopefully it dosent det its tits off.

Suppose i could fire a 1.9mm HG in at a later date.

if you have some half decent management you should be able to keep her from detting just fine.

Phil

[daniel_g]

if you have some half decent management you should be able to keep her from detting just fine.

Phil

Nope lol, just a GT ECU for now haha.

[Dickydan]

Emanage and youll be fine