evotuner04

iTrader: (45)

Then i'd do ef3 all the way, trust me you'd have an erection all day long lol

when you call map ask for dan, tell him chris barnett sent you, hes a good guy to talk to

Ramonski

iTrader: (18)

^^^ok man will do. Thanks for the help. I'll update this thread tomorrow after I talk to MAP.

Charlie87

Has anyone with a CT9A with a built 2L gone with an EF3? I cant seem to find any information.

I have ordered my EF3 (anti surge cover, ported comp housing, ported exhaust housing with the new turbosmart billet actuator)

My motor consists of (evo 8):
MAP ultimate I beam rods
MAP H11 headstuds
Wiseco 1400HD 10.0:1 CR pistons
stock crank
GSC S2 cams
supertech dual valve springs and titanium retainers
E85

with all the supporting mods like exhaust intake, 70mm tb etc etc.

what im trying to find out is
- What sort of power would I be looking at
- How much boost should i be pushing (i was thinking 28-30psi?)
- When would i be hitting full boost (i was told approx 5k by a friend of mine, which imo is WAY too laggy. I was aiming for low 4000s)
- What sort of RPM would i be able to rev the motor to safely for time attack racing
- What sort of RPM will the EF3 be running out of puff by?

Thanks!

getsideways

iTrader: (18)

I will give you a little to think about, On my stock block on a killer tune it (EF3) made 52xWHP On S1 cams Stock TB and Stock pistons (Your Compression should be worth 10-15whp). This was at a 33PSI spike i do not think it or any turbo would be happy running lapping days or HPDE for extended amounts of time at this level.

1. I would assume you would be able to max out this turbo in the 480-550 range dependant on dyno.
2. Your pistons help here, You should be able to run 25-26PSI and acheive 450WHP easily Its harder to guess what the engine will let you produce peak pressure at with blowby backpressure and the compression.
3. Should see full boost in 3rd easily between 3900-4300 Dependant on a lot of things.
4.RPMs are hard on everything, Could you rev to 8500 a lot... Yes, Will your engine, trans clutch, last longer if you stay under 7500 Yes!
5.Once again your compression helps again, but i did pulls on the stock engine to 8000 several times although the boost was falling back to 26PSI by then i was still making a flat powerband no real dropoff, the internal shift light in my brain wasnt going nuts at all.

If your going for an all out kill setting an Internal/External WG setup will help when maxing out stockframe turbos.
I think this is a built 2.0
https://www.evolutionm.net/forums/mo...ld-thread.html

Charlie87

awesome! thanks for the informative reply mate

CurseDSM

iTrader: (3)

It depends on where I start my pull. If I start my pull at 2k or even 2500, I get full boost by 5k. If I start at 3k its a little later just depends. I know this has been covered a bunch of time. I know Tom pulled alot of tq back during my pull to help it tq later so that affects my spool as well. If your looking for a tq monster then yeah definately not for a stock block. The way it has to be tuned to keep tq down from letting it gernade then yes it sucks. I know getsideways has a built motor with his ef3 and its a monster. I would say an ef4 for a stock block isn't a good choice I would disagree with that. If the car is tuned right, it is no different then any other larger turbo. I mean even if you didn't go ***** out like I did right now and just wanted it for low power, it would be a great turbo.

mrfred

iTrader: (50)

Based on my experience logging exhaust manifold pressure, trying to push the boost at high rpms is what stresses a small turbo the most. In the peak efficiency range of my BBK, exhaust manifold back pressure at 3500 rpm was only 18 psi with boost at 28 psi. At 4500 rpm, exhaust manifold back pressure was 22 psi with boost at 33 psi. These are favorable values with exhaust manifold pressure well below boost pressure. By 7500 rpm and 26 psi where the turbo is way out of its efficiency range, exhaust manifold pressure was up to 50 psi. That's a very unfavorable ratio for extended pounding. For road racing, keeping the exhaust manifold pressure below boost pressure seems like a desirable goal. I think this would allow you to run 30-33 psi no prob in peak efficiency range but then have to taper boost to something fairly conservative at higher rpms.

Ramonski

iTrader: (18)

soooo I'm still debating on wether or not I should pull the trigger on an ef4 and build the block later on or just get an ef3 and leave the block stock lol I talked to Dan over at MAP and he was a HUGE help with answering my questions but its definitely just up to me now and whats my preference.

CurseDSM

iTrader: (3)

I know how you feel I was in the same boat. I just figured what the hell I mine as well get the turbo being i can tune it to hold with the block being stock

Kracka

iTrader: (49)

The EF3 is a very nice well-rounded turbo for the street. The EF4 is a bit laggier than I'd want on a 2.0L, but that's just my 2-cents. If you do end up building the engine down the line it's a simple upgrade for MAP to turn an EF3 into an EF4 (my friend's is actually in process as I type).

murlo26

iTrader: (9)

x2

On a stock motor stick with the EF3. The EF4 is really meant for a built motor. It's a lot cheaper to send the EF3 in to become an EF4 than paying for a new shortblock. I know you can detune the EF4 but then you mind as well have the fat powerband of the EF3.

It's really personal preference, there is no "right" answer.

CurseDSM

iTrader: (3)

I totally agree 100%

tscompusa

iTrader: (31)

The ef4 is safer to push on the stock block.. the longer the tq curve is delayed the less abuse on the engine and stress.. thats what i gathered after tuning tons of stock blocks to high power levels.

sure the ef3 is much funner then the ef4 on a 2.0L, but if you want anything over 500whp+ safely, id go with the ef4 and deal with the lag.. its better then grenading with fast spool and more tq at lower rpm with far less hp..

Overlaying the ef4 curve to the HX40 on a 2.0 its identical.. and that lag is whats allowing scotts engine to stay together at 600WHP+ and track speeds to back it up.

murlo26

iTrader: (9)

Yes, this is true Tom. Regardless of turbo selection, torque management is key.

However, people need to not always focus on peak numbers. That is where I was going with when I said "fatter powerband" on the EF3. Sure the EF4 might get a person to their magical 500whp goal on stock block, but the EF3 could be faster all over still even with keeping the torque lower yet as the powerband is better.

There is always give and take with setups like this. It all depends on the risk you want to take and your overall goals with the car.

CurseDSM

iTrader: (3)

I think your kinda missing the point of the fatter powerband. On a stock block that fatter powerband even on an ef3 still puts the motor at jepordy. It is still getting there fast and hitting hard. It puts a big shock on the motor and the rods. With the laggier turbo you can prolong that to where the turbo is making the spool but keeping the tq naturally down being because of the lag. 3 port will help that push the tq band out further keeping less shock on the motor.