Super ETA w/ "I" swap -any reliable figures on increase in HP & torque?

[TheTacoMan]

I believe a stock 885 head (I) on the Seta Na is making 160-165whp with Megasquirt/miller. Im making 220whp with 7psi on an modest tune with my seta.
When I was na it ran like stock as long as you had the right afm and FPR

[CptnVortex]

I miss the local Dyno Day here in Vancouver every year... I really need to go one day. I did the I Head swap on my SETA. I also installed 19lb Injectors, and the Miller PSIK kit, with 2.7l chip. It really brings the car alive. Torque from 1500rpm up is great, and power ramps up like crazy over 3500rpm. I also recently installed a 3.25 LSD. Best upgrade by far!

Oh, don't forget, but making the car lighter also makes a huge difference... I removed the trunk tar/sound deadening, removed the A/C system, removed the PowerSteering system, power antenna.... pretty much anything I could get rid of that I didnt need... that alone made the car feel much quicker!

[AlphaE]

did the i swap this winter on seta.

i cam, dual valve springs, 173ecm, i intake, TB, 17lb green top injector.

For a while i ran the seta AFM, and it ran fine on it actually. some what unsteady idle but driveable when cold. as it warmed up the idle got very lopey, sounded neat. but when it finally got warm it idles fine.

swapped in i AFM meter. seems to idle bit smoother but not like before the swap.

ALSO: it seems, like the tip in for throttle is off. Like it struggles, runs rich maybe, when just starting to let the clutch out. it wants to die at the rpm (before swap) i used to engage clutch.... but enough of that.

HERE ARE THE NUMBER FROM A GTECH METER- not sure on the model but it gave me numbers. u enter ur car weight, calibrate the tach and make runs in second gear. Here are my runs. not very consistent (probably my driving) but i think it makes the case.

STOCK SETA w 118K miles
HP TRQ
94 124
80 113
79 114
77 111



AFTER i CONVERSION
138 171
120 165
139 158
108 135
117 142
111 136

This is w the seta afm and stock 279 rear end.

[e30Rooster]

171 tq yeah right. Post a real dyno chart

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[AlphaE]

I never said they where 100% accurate. I DID say that the numbers are all over the place.

whos to say how accurate a chassis dyno is. Lots of room for error, Calibration and operator. It was just a way comparing before and after. Even it's off, itd be off same amount for both runs. The before numbers seem accurate.

And look at the rest of the runs. Not just the highs and lows. Average them out. It show significant gains.

These are numbers from the same meter. So it's apples to apples in my book. Plus I don't really care. It was super cheap and bottom line is it makes more power and is fun to drive.

DO THE CONVERSION. It's worth it.

[AlphaE]

What 2.7 chip are u guys runnin?

[CabbE30]

1. Do the swap correctly and there will be no reliability issues. Period.
That includes all the gaskets, seals, etc.,
2. I recommend replacing the seta head with a good "i" head that already has the cam, springs, etc. Once again, take your time, follow a Bentley, and there will be NO change in reliability.
3. Read the sticky in the "M20" sub-forum if you haven't already, all the parts are listed in there.
4. If you've done a timing belt, then you've almost have done a head replacement.
5. I think you should do it, you'll enjoy it, Get a 3.xxS diff.

[Gary Horneck]

With the EU323i/731 head. The correction factor on that dyno is 1.21

Which would be 168hp/180tq

[phillye30fanboy]

I'm working on my 2.7i swap. Maybe when it's done I'll throw it on the dyno at work. I have "i" inner valve springs, intake mani, throttle body, injectors, fuel rail, 173 ecu. pretty much everything I need. One issue is the SETA has a smaller throttle body opening so the intake boot either needs to be stretched a bit to fit the opening, since it's a SETA specific part no other intake boot has the right size opening that fits the "i" throttle body while also retaining the ICV opening. Other than that i'm working on pulling the head to replace this broken rocker arm, and put on the inner valve springs. After that i'll slap on all the "i" parts

[AlphaE]

i found an i boot that worked...
part number
13711708800 i think... it looks like whats on my car now.

i had to modify the vac lines that went to the MC but it works. just capped one off. used mixed parts of e and i and a rubber plug to make it with the MC.

[Yogawrench]

With the EU323i/731 head. The correction factor on that dyno is 1.21

Which would be 168hp/180tq

These numbers are more in line with what I had been thinking. If I recall correctly, the stock 1988 Super ETA had a 2.7 ltr engine producing 120 hp and 170+ torque new. The stock "I" is a 2.5 ltr engine producing 167 hp and 177 ft. pounds of torque. If you mate the ETA 2.7 block with the proper "I" top-end, I would expect the engine to theoretically produce 167 hp and 177 torque. But since the 2.7 ltr engine has a larger stroke, I thought perhaps the Super ETA and "I" combo would produce numbers in excess of the stock "I" engine.

Any thoughts on this?

[e30Rooster]

These numbers are more in line with what I had been thinking. If I recall correctly, the stock 1988 Super ETA had a 2.7 ltr engine producing 120 hp and 170+ torque new. The stock "I" is a 2.5 ltr engine producing 167 hp and 177 ft. pounds of torque. If you mate the ETA 2.7 block with the proper "I" top-end, I would expect the engine to theoretically produce 167 hp and 177 torque. But since the 2.7 ltr engine has a larger stroke, I thought perhaps the Super ETA and "I" combo would produce numbers in excess of the stock "I" engine.

Any thoughts on this?

Most people in this thread will get their hearts destroyed on the dyno.

Expect 145ish hp/165ish tq from the eta with 885 head combo.

Post up a real dyno or stfu with this theory crafting garbage.

/thread.

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[e30Rooster]

With the EU323i/731 head. The correction factor on that dyno is 1.21

Which would be 168hp/180tq

What is the correction factor for? The tranny? Diff?

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[jlevie]

These numbers are more in line with what I had been thinking. If I recall correctly, the stock 1988 Super ETA had a 2.7 ltr engine producing 120 hp and 170+ torque new. The stock "I" is a 2.5 ltr engine producing 167 hp and 177 ft. pounds of torque. If you mate the ETA 2.7 block with the proper "I" top-end, I would expect the engine to theoretically produce 167 hp and 177 torque. But since the 2.7 ltr engine has a larger stroke, I thought perhaps the Super ETA and "I" combo would produce numbers in excess of the stock "I" engine.

The "book numbers" (measured at the flywheel) for an M20B25 are 168hp @ 5800rpms and 164lbs tq @4300rpms. I don't have numbers for a SuperETA, but the numbers for an ETA are 122hp @ 4250 and 170lbs tq @ 3200. I think the SuperETA will have slightly higher numbers. Since compression ratio won't materially change in the case a reasonable expectation for the combination would be ~168hp and ~170lbs tq.

Chassis dyno numbers will be less due to drive train numbers. About 15% is a reasonable expectation. It also matters what dyno is used. A DynoJet tends to be optimistic and a Mustang conservative for example.

[Yogawrench]

The "book numbers" (measured at the flywheel) for an M20B25 are 168hp @ 5800rpms and 164lbs tq @4300rpms. I don't have numbers for a SuperETA, but the numbers for an ETA are 122hp @ 4250 and 170lbs tq @ 3200. I think the SuperETA will have slightly higher numbers. Since compression ratio won't materially change in the case a reasonable expectation for the combination would be ~168hp and ~170lbs tq.

Chassis dyno numbers will be less due to drive train numbers. About 15% is a reasonable expectation. It also matters what dyno is used. A DynoJet tends to be optimistic and a Mustang conservative for example.

Thanks! I think that helps answer my question.