It's all been placed into consideration dude.
The 4EFTE as standard, is a non-interferance engine, so hopefully, they'll be plenty of room between the two, to allow maximum compression!
High compression, turbo.
- Thread starter Sigma
- Start date
It's all been placed into consideration dude.
The 4EFTE as standard, is a non-interferance engine, so hopefully, they'll be plenty of room between the two, to allow maximum compression!
Starlet_Sam
Moderator, Regional Area Reps Supervisor & Gay Car
But Dub-Se7en did over 200 on the standard CT9, not a hybrid.
Phil
Super Moderator
so why not build a forged engine, similar to what you have specified with standard compression, gt25 and a tiny chargecooler to get temps down and reduce lag.
what about putting a turbo in the exhaust system in place of the backbox? run with no intercooler? seen in done on a mi16 pug track/rallycar.
only if your trying to be different obviously!
Phil
what about putting a turbo in the exhaust system in place of the backbox? run with no intercooler? seen in done on a mi16 pug track/rallycar.
only if your trying to be different obviously!
Phil
Phil
Super Moderator
didnt realise that sorry.
munday
Member +
I still dont think its the best idea. Fair enough to have high compression and a small turbo, i think thats a great idea for drivability.
But i think to try and have one that screams round to 8-9k rpm is wrong. To do that you need cams, which shift the power up the revs and the whole point of having low down power and response is lost.
With regard to the ported and polished head increasing lag...i dont think it will happen. The point is that you will be getting more air through the head for a given inlet pressure, so same air pressure but more of it going through, should help spoolup if anything. And as for the rough vs smooth inlet port debate, IMO smooth is better...you will still get quite a bit of turbulance to mix the fuel/air charge. Thats only my own thinking though...based on nothing scientific :rockon:
:drive:
weeJohn
Lifer
-Fully destress, remove all casting marks, have baring tolorances perfected.
-Remove as much mass as possible, drill and balance standard flywheel.
-Cross drill, mass removal and balance standard crankshaft.
-Fit lightest weight forged conrods I can find.
-Fit hemi, forged pistons.
-Deck the engine block as far as possible, raising compression upto around 9.5-10:1.
-Machine the bores so they are perfectly circular, and match factory specifications.
-Cross hone bores.
You are planning on reducing the strength of 2 things that you plan to spin at way above their rated/designed spin rate, and increase the loads on them also by increasing compression, is that a good idea?
Hemi pistons? as in hemisphericle, as in dished, as in lowered compression ratio or as in domed, that are raised into the combustion chamber to raise compression?
Deck the block to raise compression, in other words have the pistons travel out of the block further and into the squish area, where you will have larger valves that are being lifted further and for longer?
If you rebore and rehone the cylinders they will be larger, how will you return them to factory specifications?
I think you need to do a bit more thinking.
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stedee
Member +
i have heard it is important to have rough inlet walls or the petrol comes out of the mix and evaporates on the walls, i do know that alfa boxer engines have inlet valves that open at slightly different times to aid in turbulance.
stedee
Member +
i have heard it is important to have rough inlet walls or the petrol comes out of the mix and evaporates on the walls, i do know that alfa boxer engines have inlet valves that open at slightly different times to aid in turbulance.
boostedep91
Fresh Recruit
Its nice to try and think different
Well for one you will never get a 4E or 5E to have the same characteristics as a V-tec. The V-tec uses 2 different cam profiles so there is one for slower engine speeds then another for higher rpm so you dont loose driveability. If you put big N/A style cams in you will move the power band up and loose your driveability low down. You need the compression to suport the cam so a 10.5 comp and big N/A cam is fine for high engine speeds and N/A application. With a turbo and pump fuel your kidding yourself. Also big N/A cams do not go great with turbos miss matched.
And then there is bore to stroke ratios which define how an engine operates to a degree. Oversquare means bigger bore then stroke like a
b16: bore 81mm stroke 77.4mm.
These engine are revier in nature at the expense of low-end torque. Undersquare means smaller bore to stroke like a
4efte: bore 74mm, stroke 77.4mm or 5efhe: bore 74mm stroke 87mm. Undersquare engine usually has a lower redline than an oversquare one, but it may generate more low-end torque. undersquare engine can have a higher compression ratio with the same octane fuel compared to a similar displacement engine with a higher bore/stroke ratio.
Head designs well 4E/5E heads are not the best for power and flow there made for efficiency. Unlike the V-Tec heads.
Max comp maybe up to 9.5:1 and a bigger turbo then ct9 prob like gt25/28.
Rough inlet walls are better or the fuel will not atomize/mix with the air. It will just stick to the sides of the port and pool. Can cause issues. Exhaust ports can be smooth.
I have a 5E-FHE with std turbo pistons, std fhe rods, std headgasket, std head, with a gt28r. Comp around 9.0:1 max boost about 3500 redline at 7000. 230whp @ 17psi
more drivable then any v-tec more fun to.
Dave
Well for one you will never get a 4E or 5E to have the same characteristics as a V-tec. The V-tec uses 2 different cam profiles so there is one for slower engine speeds then another for higher rpm so you dont loose driveability. If you put big N/A style cams in you will move the power band up and loose your driveability low down. You need the compression to suport the cam so a 10.5 comp and big N/A cam is fine for high engine speeds and N/A application. With a turbo and pump fuel your kidding yourself. Also big N/A cams do not go great with turbos miss matched.
And then there is bore to stroke ratios which define how an engine operates to a degree. Oversquare means bigger bore then stroke like a
b16: bore 81mm stroke 77.4mm.
These engine are revier in nature at the expense of low-end torque. Undersquare means smaller bore to stroke like a
4efte: bore 74mm, stroke 77.4mm or 5efhe: bore 74mm stroke 87mm. Undersquare engine usually has a lower redline than an oversquare one, but it may generate more low-end torque. undersquare engine can have a higher compression ratio with the same octane fuel compared to a similar displacement engine with a higher bore/stroke ratio.
Head designs well 4E/5E heads are not the best for power and flow there made for efficiency. Unlike the V-Tec heads.
Max comp maybe up to 9.5:1 and a bigger turbo then ct9 prob like gt25/28.
Rough inlet walls are better or the fuel will not atomize/mix with the air. It will just stick to the sides of the port and pool. Can cause issues. Exhaust ports can be smooth.
I have a 5E-FHE with std turbo pistons, std fhe rods, std headgasket, std head, with a gt28r. Comp around 9.0:1 max boost about 3500 redline at 7000. 230whp @ 17psi
more drivable then any v-tec more fun to.
Dave
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Phil
Super Moderator
yes
Chris@CCM
Member +
nope its not phil its from cynos or what ever there called the paseo is a 5efe. i would looking at weejohns ponts too
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Dave@TM-developments.com
Trader
Or from a Sera