Pro Stock John

iTrader: (34)

So is that still a 76mm turbo or is it a 87mm turbo now?

Forcefed86

iTrader: (4)

Currently I run an 83/74 exh wheel with the 1.10 T4 housing, Cast 74.5mm compressor.

New turbo is a 87/81 exh wheel with a 1.25 T4, Billet 76mm compressor.

On a side note for those that don’t know…

The billet stuff usually “cheats” on blade sizing. Racing turbo classes are limited to the OD of the compressor inducer wheel. So the billet guys cheat a bit and lengthen the blades towards the hub. So a “76mm billet” wheel may actually have the same overall blade length as a cast 80mm turbo. This is what gives the billet guys the edge. So jumping from a cast 74.5 to a billet “76” is a pretty big upgrade.

For example both wheels in this pic measure 67mm outside diameter. You can see the billet unit has a smaller hub and longer baldes. This allows it to move more air. They also extend the tips on the exducer wheel to push a bit more air.

Pro Stock John

iTrader: (34)

Thanks for explaining. I have noticed in classes like Ultra that the billet 76 and cast 80 are run at the same weight.

Forcefed86

iTrader: (4)

Picked up a $30 MAC valve and hooked it up to my AEM and the lower Wg port only. Pretty fun! Ramping boost in by RPM at the moment. Around 5psi at 3200, then I dump it all in by 6k. I still spin around 5800 in 1st, but some fine tuning should fix that. I saw 18lbs by 6k. If I can get that around 14 I don't think I'll spin. It's plenty fast for the street this way.

Hoping I can just program the MAC valve closed at the track and use the in cab regulator to apply pressure to the top WG port alone and hit 20-25psi at the track.

aknovaman

iTrader: (7)

Valve source to purchase one?

Never mind. eBay is a good place.

Forcefed86

iTrader: (4)

Ebay. Just type “mac solenoid”. Was $30 shipped with the fittings and filter.

http://www.ebay.com/itm/MAC-Boost-solenoid-valve-BCS-35A-AAA-DDBA-1BA-compatible-with-most-ECUs-EMS-PWM-/331006948808?pt=Motors_Car_Truck_Parts_Accessories&hash=item4d118d35c8&vxp=mtr

Originally I tried a GM boost solenoid and it never worked correctly. So I gave up on the AEM boost control option. Got the itch again and bench tested the GM solenoid. It would just hang at anything over 12psi. The mac valve was a champ and still operated fine at 30psi at a 31hz freq. 61hz had a better resolution, but less overall range. I didn’t have any settings in between on the AEM.

Forcefed86

iTrader: (4)

Wait 3 weeks to run and I get bad gas and the damn WG seizes in the open position. Got 2 runs in, couldn't make over 15psi. Trapped 145 at 15lbs though. Faught traction all night leaving at 5psi off the foot brake! My third run I built about 1lb of boost by 6k.

Looked into things a bit more this morning.

Tested my fuel. 60% ethanol.

Pulled the gate apart and found a screw had backed out of the body. Also lost 2 of the spacers. Substituted some washers in and snugged everything back up with locktite. Seems to be a worker now.

Also found a nice easy way to pull apart and assemble the WG. Very easy to line everything up this way and not pinch the diaphragm.

Forcefed86

iTrader: (4)

Made it to the track finally. Blew my charge pipes off 5 times and called it quits. Manage to trap 150 and a 149 on the video pass below. Spun bad both times. Seems to be unloading when the front end comes down. I tried adding more boost but then I'd spin on the line.

This is a 4-5lb t-brake launch. (9lbs to 5500 on the boost controller and ramps in 20-21lbs after 5500.

Need to get some sort of bead on the throttle body. Threw my slicks back on to try for next time as well.

You can hear the tires spin when the nose comes back down.

cruisin'73

iTrader: (8)

You may consider TIG welding to add a bead to the throttle body. TIG would not introduce AS MUCH head into the throttle body. And you should still be able to build up enough of a bead to retain the clamp. Just a thought. Great build and thread, lots of inspiring budget ideas and top notch work! Thanks for sharing.

Forcefed86

iTrader: (4)

Thought about that. None of my "tig buds" felt they could add a bead without deforming it. (aka they were busy ) I would have tried it if I had an decent tig setup.

Speaking of budget... here is my throttle body solution.

Started by roughing up the entire contact patch of the coupler. Then used a small file right under the tiny excuse for a bead that comes on the LS1 TB. Ended up with a more pronounced bead for sure just doing this. Then filed down the supports around the base of the TB to allow the coupler to be pushed on farther and a 3/4" wide T-bolt clamp to be installed and remain behind the bead.



Cleaned it really well with lacquer thinner and taped off the bead area. Then applied an 1/8 or so build up of JB quik weld. And pealed the tape off. Now I have a nice bead up behind the factory bead area.

I'll file/sand it a bit once it sets.

Plan to install it with hairspray. I'll report back once I get some testing on it.

Forcefed86

iTrader: (4)

Tired of messing with oil spray and leaky pans etc. Put an electric VAC pump I had laying around on tonight. I thought it turned out pretty slick all tucked away. I'll have my ECU turn the pump on at 1lb of boost.

Forcefed86

iTrader: (4)

Man this thing makes boost fast! So on the brake I load up to 3500rpm on the 2 step. I build 4.48lbs and release the brake. Literally 1.3 seconds later i'm at 21lbs. This keeps blowing off the tires. Running a 29x12 slick and I can't get traction. Managed 9.2's all night at 154mph @21 psi! 1.5x 60's. This thing has 8.7x's in it with a decent launch. Videos soon to come!

SSSTANG#1

iTrader: (14)

How much does it weigh?

Forcefed86

iTrader: (4)

Weighed 2950 last year with me in it.

Unfortunately I didn't have the nice HD cam going. I guess ti doesn't' work well at night. This was taken with an Iphone. Can't get much from it, other than the driver side is still coming up much higher than the passenger side. Time slip will be at the end of the video...

Forcefed86

iTrader: (4)

Strapped the front end down and played with the ladder bars a bit. Bars were setup neutral without driver previously. Now I have them setup neutral with me in the car. (slip fit FWD mount bolt on pass side bar with driver.)

Seems to launch pretty straight. Ithink with a some fine tuning on the bars and loosening up the straps a bit I'll get my 1.3x's back. I managed solid 1.40-1.44 60's all night. Kinda boring now just hooks and goes!

60' 1.43
1/8 5.89 @121.49
1/4 9.02 154.27


60' 1.40
1/8 5.84 @ 122.6
1/4 9.01 @ 155.4

Rx7FB6l

Thanks for the link to your build! Awesome and inspirational.

Forcefed86

iTrader: (4)

I think the small cast S475 turbo is out of steam (on my combo anyway). Going from 22.5lbs at 15.6* of timing to 25lbs and 17* I picked up about 1 mph. I'm sure my IC core ($120 china Ebay junk) has horrible pressure drop, and my "T" merge hotside is not helping any either.

New turbo is installed!

Hope this will free up some power back pressure wise and give me alittle boost on the comp. side as well. Who knows with that little S410 cover though I may not go any faster.

New turbo is 2lbs heavier and about 1.5" taller (center section is longer)

Hank Peabody

iTrader: (2)

I wonder if some of the Gen 4 VVT engines have retarded crank gears because of the VVT? Maybe there is some time like coasting where having retarding cam timing is useful, so the factory installs it all really retarded and under 99% of the conditions the VVT is advancing the cam to remove that retardation.

I have an LY6 that had VVT. I installed my cam straight up and always thought my car spooled super lazy for what it is (6.0 and PT76), so maybe my cam is retarded 6* too. Thats what I get for being lazy and not degreeing maybe??

Verz

iTrader: (21)

New shiny things! Is the compressor inlet smaller also? Can tell a big diff in the outlet size though the overall cover doesnt appear to be any smaller

Forcefed86

iTrader: (4)

Others I know with gen4 motors were pretty close with the OEM set when checked with a degree wheel. So I don't think the problem applies to all 4gen vvt/dod motors. I could have just been unlucky and got a crank keyway that was off. Still waiting to hear back from the cam supplier as well. He has my original cam and was going to degree it on his motor to double check it.

Going to try it out this weekend I hope! Inlet is the same 5". Out let is noticeably smaller ID as well as OD. Kinda ticked the same supplier I bought my turbo from now has a billet 11 blade compressor and a 75mm billet race impeller with the larger S400 compressor covers for the same price. I can get the race cover for my unit for $250. Should be worth around an additional 50hp with the turbo maxed out according to Apex turbo. May go that route once I sell my S400.