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My 240SX
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My turbo KA story - The buildup, the blow-up, the rebuild, the dyno...

So after helping to install the turbo on a local S14 I had to build one of my own...

And then, as I was planning the setup, I read up on an idea to pull a DSM trick and hack the MAF to compensate for bigger injectors.

So I ran the 370CC injectors and hacked MAF for a week while I was still N/A, then got all the turbo parts in, and began the install.

(For reference, this was in the beginning of February of 2003...)

First issue:

Pulled the header to test fit the RevHard Manifold...and it hit the brake master cylinder - Not a little - It wouldn't fit at all.

Turns out the Auto equipped cars (mine is now a 5-speed) have a smaller diameter brake booster, but it extends towards the front of the car 2" more = No room for tangential T3/T4 turbo.

So I swapped the M/C off a 5-speed S14 and had more room, but barely enough...

So now the mani fits, and the turbo will I cut between the runners to allow for expansion and drilled out the bolt holes for the same reason, and so the manifld flange better lined up with the exhaust ports on the head (needed to be moved down ~1/4 inch to center the holes).

I started the real install on a Saturday afternoon...

I rented a welder (Lincoln 100) and started at 5pm, worked 'til 2am and fabricated a 2.5" downpipe with O2 bung, welded the BOV flange onto a piece of 2.25" piping for the intake, and drilled the oil pan for the bung, among other things...

Sunday I ran the oil lines, fabbed the intake piping, welded the oil pan (a couple times...and still wound up with a poor weld) and got the beast running, but on wet roads.

Sideways everywhere!

Developed a vacuum leak Sunday night around midnight and left the car home Monday, fixed it after work, and installed the turbo intake and BOV, and boosted some more...

The setup is as follows, all new parts:

Garret T3/T4, 57 trim, .63 A/R (2.75" inlet, 2" outlet)
RevHard Manifold
JGS oil line feed and drain kits
370cc injectors teamed with a hacked MAF (blow-thru setup)
TiAL wastegate, .3bar spring (4.35psi...for now)
No intercooler...2.25" intake piping.
1st Gen. DSM BOV, slightly crushed.

ACT "street/strip" clutch (organic disc)

It pulled hard, even at just over 4psi. I was happy...

And cost...the big question:

Turbo, wastegate, DP flange = $780
RevHard Manifold = $350 - Second hand but brand new...
Injectors = $100
BOV (eBay) = $55
ACT Clutch = $200 (used, and installed prior to turboing the car)
Autometer Phantom Gauges (A/F and Boost) = $107
JGS oil lines and fittings = $80
Mandrel Piping (from Jegs) = $60
Hose Couplers (truck rad. hose, 2.25" + 3") = $30

So that's $1,762, but add $100 for misc stuff like clamps, a brass "T" for the turbo inlet, RTV, vacuum hoses, etc...

So call it $1,862 for a custom T3/T4 setup with room to grow to a max of 250-255rwhp @ 8-9psi.

[ *EDIT* (May '03) - Add $800 for the GReddy VSPL intercooler kit, and you have ~$2,700 TOTAL for right at 250rwhp @ 8psi. ]

[ *EDIT* (April '04) - Add $750 for a *used* JWT ECU and fuel setup, and you now have $3,450 TOTAL for 310rwhp @ ~12psi. ]

[ *EDIT* (Feb '07) - Add $600 for a *used* "Ground Zero" exhaust manifold, and you now have $4,050 TOTAL...for 338rwhp @ ~12psi. ]

Here are a couple pics of the original setup:

The original 'Hacked MAF' - Taped up for testing...the current one looks much better:

Turbo Close-up - Shows clearance issues:

The engine bay before the intercooler:

But 2 weeks later...

KA-T: Blown up, rebuilt, and dyno'd...all in 48hrs.

Considering I'm using a hacked MAF and no intercooler, I was anxious to dyno it and see the A/F ratios, and of course the power.

But not without testing it first...

And testing revealed that I had WAY too much timing from the JWT N/A ECU upgrade I was running at the time...

So here's the story:

Thursday night is our weekly car meeting for International Motorsports, the University of Florida Sports Car Club.

I hadn't really been able to boost my car much on open roads, no chance to flog it to see how it held up.

I had, however, turned the boost up to my final-with-no-intercooler-boost level of .4bar (5.8psi) from the original .3bar (4.35psi).

Car felt great, but was still leaking a little oil when I parked it. And the timing was a little much for a turbo car, but it was doing big deal, right? Wrong...!!!

So that Thursday, I took the car out with a small group of guys to do some boosting, and see how the car responded.

I drove for about 30 minutes, much of it in boost, and was having a great time until we stopped for gas and I noticed the idle was bad...sounded like an old VW Beetle.

Checked the oil, and it was _low_...added 1 quart. I figured (hoped) I blew out the exhaust gaskets, as I re-used the ones from before the turbo setup...and eveloped a boost leak...etc, etc...but as I left to head 15 miles home, the car ran like sh!t at any RPM under 2000. Being an optimist, I hoped the low oil didn't cause any harm...and I REALLY hoped the motor was OK otherwise.

So I get home around 1:30, spend an hour with the car checking plugs, gaskets, etc...found nothing definitve, so I went to bed - Had to be at work at 8:30.

Work was a little slow, so I took off the last 2 hours of the day and went to Nissan and got gaskets, and picked up a compression tester just to see...

Pulled the turbo, manifold, plugs, etc...and inspected everything - All looked good. So time for the compression check:

#1 = 180psi
#2 = 179psi
#3 = 181psi
#4 = 30psi - sh!t...

It's now 5:00pm on Friday, and I'm to leave for Orlando at 9:00 the next morning to go to the dyno. Better pull the engine apart and see what happened! A friend (Chris L.) came over and we started the teardown.

Pull all the misc stuff off, then the head, and headgasket looked good. #4 showed no signs of detonation at the piston, and I figured from the start it was rings anyway, so I figured might as well pull the piston/rod and find out.

Dropped the oil pan and removed the rod bolts, pushed the piston out the top, and voila!...broken ring land above the oil ring, and the next one up was cracked as well.

Here's the pic:

I clearly had a little detonation from too much timing - The JWT N/A ECU gives close to 28* total timing...way too much for a boosted 9.5:1 motor.

Well, as luck would have it, I had and extra set of pistons and rods from a blown KA that was given to me, but one piston looked great still.

So we swapped the oil rings from the bad piston to the new one, and swapped the rod and wrist pin, the carefully re-installed exactly as it came out...

Put the engine back together - Now it's 2:30am, 6.5hrs 'til we leave for the dyno.

Finish replacing the oil pan (after fixing the return line hole so it flowed properly and wouldn't back up causing a leak again) and re installed the head, cams, upper timing chain cover, upper chain itself, etc, etc...Until we have it back together enough to check the compression.

Now, of course the engine was cold, but we figured we'd give it a go just to see - 155psi. Much better, but I was still concerned.

Got the engine running and filled with coolant and oil, warmed her up, and double checked all our work.

Checked the compression again: 182psi!!!! Hell yeah!!!

Took it for a test drive, and it felt like new...

It's now 4:30 - Took a shower, got some sleep.

9:00am Saturday - Get up, fab an oil restrictor for the turbo feed (1/16" restrictor), and head for Orlando with 3 extra quarts of oil and coolant and tools, etc...Dyno here we come!

We stop about every 30 minutes to check it all, and it looks good.

Get to 'Vinci Hi Performance' in Orlando around 1:00pm, home of 'Garage Advance' and the dyno.

Retard the timing a little to be safe, knocked it to 14-15 BTDC base...

Stap the car on around 2:30 and make 3 pulls - 2 @ .4bar, and one at .3 just to see what it put out.

First pull: .4bar, 3rd gear = 215rwhp and 209rwtq - Not bad!

Second pull: .4bar, 4th gear = 224rwhp and 229rwtq - Wow...

Third pull: .3 bar, 4th gear = 202rwhp and 209rwtq

My initial goal was to put down over 200rwhp @ less than 6psi...I was VERY happy.

A/Fs were 11.5-12.0:1 as boost built, then 12.7:1 as boost spiked about .5psi, then evened out at full boost on all 3 pulls at 10.6-10.8:1 - Rich, but safe.

See these dyno charts here...

So in 48hrs, I killed it, resurected it, tested it, and dyno'd it - Hard work but fun - Well worth ALL the effort.


May '03: Now it's intercooled and boosted to 8psi - Oh yeah!!! See here for the details...

Sept '03: Dyno'd at 8psi - 248rwhp - See here for the dyno chart...

April '04: Now it's got more fuel and a bigger an appropriate timing curve for more boost (12psi to be exact).

Feb '05: Dyno'd at 12psi - 310rwhp (uncorrected) - See here: dyno charts.

Feb '07: (wow, 2 years and all I did was race the car A TON, no real changes to the setup!)
I swapped out my trusty old RevHard manifold for a "Ground Zero Motorsports" (tubular stainless with 0.10" wall thickness - SUPER beefy)...dyno to follow.
Dyno'd 338rwhp at the same 12psi - See here: dyno charts.

Aug '07: Added a chromoly 11lb flywheel, no dyno.

October '07: Changed to a 50-trim T3/T04E - Same overall specs as my old 57-trim, but with a coated turbine hosuing...
No dyno for this either. Yet.

Tech Info / Installs
My 240SX
Links Page