As a re-fresher.....I had this thing on dyno back in August & on the 51st pull we had a wastegate failure & it overboosted & detonated & knocked ring lands out of 3 pistons. Made 1070 on one pull freak #, but made bunch of 1020-1040 HP Pulls....

@ that time I had a Borg Warner S480 80 MM turbocharger with a 97 MM turbine wheel, which was maxed out on this motor.

So I put a new set of custom Diamonds in it, & ordered a new Garrett GT91 turbo from forced inductions out of Alabama. This has a 91.5MM compressor wheel, 133 MM turbine wheel.

I finally got time to put the thing back together & get it on dyno this week.....

Back in August it made 676HP 590TQ Naturally aspirated with my dyno headers...

So yesterday we ran it in same state of tune, same spacer, same carb, same timing, same jetting right off the bat, made 4 pulls to break in the rings & it made 675HP 596TQ LOL I guess the dyno is "repeatable" 4 months later & same motor is within 1 HP. So we knew it was healthy and ready for boost.....

But before the turbo went on, we just put on the turbo headers which are straight 2" primaries with 3.5" collectors that feed into a 2.5" crossover pipe dumping into a dual 2.5" inlet feeding a T6 flange. & We made 1 pull with that exhaust system on to see how much power the exhaust would knock out..... 581HP, 550 TQ. So now I had a baseline to see exactly how much the turbo itself added....

So yesterday, we ran my Extreme Velocity "pro" carb hat.... my home made 950HP Holley blow through carb.... We started out safe @ 22 degrees timing, & 9 PSI. was making in the 850 HP range, everything looked good, so we slowly started working our way up boost wise & timing wise playing with air bleeds of various sizes in the wastegate. I bumped timing to 25 & it pretty much stayed there for the next 2 days. I'm running C16 in it & never had any hint of detonation, not sure you can detonate this stuff, especially with as much methanol as we were also pumping into the turbo & carb hat.

That was the other thing we added this time was a homemade meth injection system, I'm using a 100 PSI Bosch EFI injection pump, spraying through McMaster Carr M10 & M15 misting nozzles that I tapped into the hat & turbo. Took a few pulls to determine right size for the hat nozzle. I have an adjustable boost pressure switch that activates the meth @ 6 PSI. Anyhow, I'm just using it as a "chemical intercooler" I'm not into the added plumbing of running a cooler in my car, the meth injection will be much simpler.

Anyhow... the one thing that became strikingly clear by end of day yesterday was we had serious EGT issues with a couple cylinders. Back in August I did not have EGT sensors in the turbo headers, so I added them this time & am glad I did because it probably saved another set of pistons.

The EGT's on cylinder #3 was spiking to the mid 1500's @ the top of a pull & we were already keeping RPM low @ top of pull because of the high EGT's on that cyl in particular, & all the front cylinders were showing pretty darn hot & the rear cyls were all very cool in the 1350's @ end of a pull.

I was afraid to put any more boost in it.timing or RPM to it until we figured out how to fix the EGT's. We put 19 pulls on it yesterday & last pull of day it made 1197 HP @ 14.3 PSI boost @ 6700 RPM. & Before anyone asks how we more than doubled the power with less than 1 atmosphere of added pressure.... it's because that was @ 6700 RPM, & peak HP on the 580 HP pull with no turbo was @ 6200. But overall the turbo was showing VERY good efficiency #'s @ that boost level... the methanol was keeping the intake/carb hat/charge pipe room temp or cold. So I was very happy with that....

So we came in this AM & looked @ the EGT #'s from the motor NA to see what the fuel distribution NA was like... Hmm the rear cylinders were hot & front cylinders including # were cold NA. So the carb hat was completely reversing the EGT's & making the front stupid hot... The design of these Extreme Velocity hats has been the center of much debate in the turbo world for years.... & some have said that they do really have horrible distribution issues.... So... My Buddy Mark has been messing with Turbo stuff for years & has been saying those style hats are junk foerver.... so he has made his own hats for his Ford stuff, but never had any EGT #'s to back up what his thoughts were on how they work. His is a full round style hat similar in design to the SDCE hat if I had to pick a commercially avail hat that it is similar in design to, it's much smaller than the SDCE unit as he runs 4 cyl 2.3 Ford stuff so he does'nt need a huge volume.

So first thing we did this AM was make 1 last pull with the Ex Veloicty hat, pull with a 50/50 water/meth mix in the methanol injection tank hoping the water would enhance EGT cooling as I was told by some "gurus" it would... well if anything the EGT's were even higher on that pull. So we went back to straight methanol & we installed Mark's homemade air hat made out of a 2.3 Ford flexplate & a Tractor Supply air tank end LOL. It's not prettiest looking thing, but after today I can certainly say looks are'nt everything.

We were a little worried about the home made hat just killing power, we were not sure it could support a 1200 HP engine.... 1st pull it was down like 300 FT lbs & 300 HP to to EX Velocity hat, but AF was silly rich. Was'nt looking good for the homemade hat..... BUT the EGT's across the board were within 20 degrees on all cylinders! We were seeing damn near 200 degree spreads with the Extreme Velocity hat.... So.... we started pulling jet out.... & when I say Jet, I was making BIG changes @ one time. With the ExV hat we were running 93 secondary jet & 79 Primary with a 6.5 Power valve & the power valve channel restrictors removed.... that was around 11.7:1 AF With EGT's anywhwere from 1350 to 1550 @ top end of a pull depending on the cylinder....

I started by pulling 5 out of secondary, 4 out of Primary.... Power was up 100 HP/100 FT lbs.... AFR still way in the 10's... Hmm..... Another 5 out of secondary, another 4 out of Primary.... another 100+ HP & 100+ TQ.... Hmmmmmmmmm EGTs dead reliable across board even.... We ended up Jetted 71 Primary/82 Secondary @ the end of day today. In that Jet tune with same timing etc, @ 16.4 PSI it made EXACT SAME 1197 HP As the extreme velocity hat @ 14.3 with huge Jets....


So:
Extreme Velocity hat: Jetting 79/93 1197 HP @ 14.3 PSI with EGT's all over board, 11.7:1 AFR

Home Made Tractor Supply hat: Jetting 71/82 1197 HP @ 16.4 PSI Even EGT's 11.7:1 AFR.

EGTs on top end of a pull @ 16 PSI with the home made hat were in the 1460 range. Never went over 1500.... until I went crazy with the boost later on LOL.

Fuel usuage in the fuel cell was drastically reduced with the home made hat.... It did take more boost to make same power as the other hat, but was doing it safely & allowing me to turn motor 6800 RPM without worrying about how high the EGTs were going to go & I had very uniform distribution.

We basically spent all day today figuring out what that Hat wanted & how to tune around it. @ end of day we made a 1150 pull & another 1190 HP pull & a 997 FT lb of TQ pull... & so I of course wanted to see a 1200+ # out of greed... So I declared one more pull... we'd drill few more thousandths into one of my wastegate bleeds & see if that would do it. It made 18.6 PSI, but we did not have enough jet in it for that extra boost & it went lean in middle, but came around back up on top & made 1237 HP. It would have been alot better if we would have thrown more jet to it for that added boost but it was late & that was end of testing. It was just coming back around into near realm of where it had enough fuel @ top of the pull where it threw up the 1240 HP It did'nt go dangerous lean, just lean enough in the mid 12's to make the mid range power dip. It was in mid 1000's where should have been in mid 1100's. I think if we had 74/85 jet in it.. that pull would have been 1270's? Does'nt really matter I was determined I was not going chasing @ useless # @ that point of day. So we called it good.... the 16 PSI tune is real good repeatable 1150-1200 HP setup. & I got couple other more "street friendly" mild tunes as well which is really what I wanted to get... lots of usefull info more than just # hunting.

Obviously the most useful thing I learned was that the high $ extreme velocity hat belongs in the garbage rather than ontop of a $25K engine. I know alot of people run them but I wonder how many have any clue what it is doing to their distributuion. Not many people test these motors properly like this on an engine dyno with 8 EGT's. Alot read a single EGT @ the turbine housing, or read single AFR # from their wideband, & too many rely on chassis dyno tuning again usually with a wideband.... Those #'s are virtually meaningless if you have one or two cylinders that are on verge of melting & rest are cold & they all even out....

Anyhow.... I took some videos I'll try to get them up on Youtube tomorrow. I'm glad it's still in 1 piece & can get it in the car finally & see what we can break there in the spring.

All told we put 84 Dyno pulls on this thing in the last 2 sessions learning with it. Bottom end looked great after the first 50 pulls @ 1000 HP, so I'd expect another couple hundred HP did'nt change that. Alot of work/thrashing dyno time for a non "class" motor. Just a "street" car LOL Should be interesting.... I already have plans to take car back to BGR next winter for more tub/tire & will probably have to go to a glide to control this thing, but we'll see.