280zex Posted January 13, 2010 Share Posted January 13, 2010 OK so I finaly got the 280z on a Mustang dyno for 1 free run!! Due to the fact that I was talking some !##$@ to some of my tuner friends about my unique setup. RWHP 305 and 285 torque @ 12lbs boost!! Sorry no print-out the run was a free-bee.What amazed everybody is the fuel curve (or lack there of). The z idles at 12.9afr cruses at 12.9 and is 12.9 WOT. The fuel curve moved mabe .5 richer just as boost came in. The t3/t4oe came in at 3k rpm's and went all the way to 7k. Plenty of room for more boost!! Unfortunately I wasn't able to get the Nascar carb I got for free to work for me so I went with the old #6895 Holley 390 carb. My guess is that the older carb is spread bore vs. the square bore of the newer carb and the 280z liked the older one better. Go with what works!! Now I have to get a better clutch and trans. Here's a pic of my current progress.. Quote Link to comment Share on other sites More sharing options...
a6t8vw Posted January 13, 2010 Share Posted January 13, 2010 nice man, what mods have you done to that holley? Quote Link to comment Share on other sites More sharing options...
S130Z Posted January 13, 2010 Share Posted January 13, 2010 Great job man! This makes me wonder what my EFI setup is doing on 15psi! One question for you, what octane fuel are you running? I ask because 12.4 is a bit lean for pump gas(depending on your timing curve). Congrats! Quote Link to comment Share on other sites More sharing options...
280zex Posted January 13, 2010 Author Share Posted January 13, 2010 Holley list #6895 390cfm spread bore double pumper dual fuel feed. Quickfuel 750 metering blocks. Nitro floats .130 needle & seats. Idle feed restricters #29. Primary low speed air bleed #70. Secondary low speed air bleed #29. Blocked bolth high speed air bleeds. Blocked ALL vac lines including the power valve channel. Removed backfire check valve from base plate. Removed the secondary accel pump arm. Installed adjustable secondary throttle linkage. Cut and capped the throttle shaft ends in base plate. Made custom BOOST refrenced powervalve from a 2.5 valve(hanger 18 mod- use google search!!). Primary powervalve restrictor #77. No secondary powervalve. Installed a green pump cam on primary side on hole 2. Drilled and extended the transfer slots with a .015 hole past the throttle blade at FULL closed(not idle) position. This is for bolth primary and secondary sides. 4 corner idle adjustment. Secondary idle circuit NOT used. #25 accel pump squirter(stock). Re-useable blue gaskets.#54 primary jets. #64 secondary jets. Removed ALL choke parts. Cut off(milled) choke horn. Filled choke control arm hole(s) with fuel resistant epoxy. Hope that helps:mrgreen: Quote Link to comment Share on other sites More sharing options...
280zex Posted January 13, 2010 Author Share Posted January 13, 2010 92 octane. 18 deg timing LOCKED uni-lite dizzy(no advance/retard curve). Quote Link to comment Share on other sites More sharing options...
280zex Posted January 13, 2010 Author Share Posted January 13, 2010 There is plenty of info on how to do the mods required for blowthrough turbo/Holley. However I could possibly(mabe) modify Holley carbs for blowthrough. Money talks.I need to get a dyno print-out posted first. Video would be cool too. Quote Link to comment Share on other sites More sharing options...
PanzerAce Posted January 13, 2010 Share Posted January 13, 2010 Hmmmm....getting someone else to modify a holley for blow through.....you tempt me good sir, you tempt me... And very nice power figures. What mods to the block/head/crank/pistons/etc? Quote Link to comment Share on other sites More sharing options...
280zex Posted January 14, 2010 Author Share Posted January 14, 2010 F54 block. .5mm overbore 10cc dished and coated custom forged pistons. Forged crank with knife edege lobes. Replaced all the studs with ARP studs. Coated the interior of the block with glyptol(sp?). Forged rods stock length. N42 head with stainless valves and seats. 5 way grind on the valve seats. mild port/polish. Polished the outsied of the head and valve cover. Custom cam grind from Delta cams .480lift/280 deg rotation on solid cam. Followed TonyD's guide on balancing your valve train. Kamiari(sp?) cam gear/guide/tentioner. Custom 1 grove harmonic balencer. Turbo oil pump. Custom made head gasket. Quote Link to comment Share on other sites More sharing options...
yetterben Posted January 14, 2010 Share Posted January 14, 2010 VEry nice but you need to fatten up under boost man i would feel safer in the low 11's for sure. Quote Link to comment Share on other sites More sharing options...
turboHLS30 Posted January 14, 2010 Share Posted January 14, 2010 Nice numbers good to know that I'm not the only one one here with a blowthru L-series. Quote Link to comment Share on other sites More sharing options...
280zex Posted January 14, 2010 Author Share Posted January 14, 2010 Yetterben I can drop a point easy enough. I'll go from #64 secondary jets to #66's and let ya know. That should put me about 11.5 afr on wot. I realy like my turbo setup but it eats fuel on boost. I ran 80.5 miles(mostly 45mph to 60) and used 10 gallons of fuel. There was a bit of stop and go but not much. Could be that when I got a chance to boost I did so liberaly. Right foot to floor. Good thing my Holley has only a primary side accel pump... Quote Link to comment Share on other sites More sharing options...
yetterben Posted January 14, 2010 Share Posted January 14, 2010 8 miles to the gallon sound about right. drop your afr and bump the timing. 2-4 degrees. Might wanna start thinking about the external cooling mod for 456 on the head. turboHLS30 i am throwing my setup together youre not alone. HKs for the win. Quote Link to comment Share on other sites More sharing options...
Xnke Posted January 14, 2010 Share Posted January 14, 2010 Just to let you know, that cam is not .480 lift. Measure it and you'll see it's a .454" lift, 234* duration at .050" valve lift. (still 280* total duration, though.) Curious, why are you giving up power by running a locked dizzy? Safety net? Quote Link to comment Share on other sites More sharing options...
280zex Posted January 14, 2010 Author Share Posted January 14, 2010 Yetterben I changed 2 jet sizes to #66. AFR at WOT is now 11.4. About the cooling mods am I missing something? I didn't know about any problems. Or atleast I personaly haven't had any issues YET. Should I look for anything particular?? XNKE I measured that cam while at Delta cams with my dial indicator. It does measure .480 lift. It does seem to have a bit of a steep ramp angle though. Mabe due to re-gringing? I think I'll check it again and let ya know. So far this setup has about 500 miles Turbo charged. I have 5k miles on the engine BEFORE the turbo was added. I might just pull the head off when I take the intake and exhaust manifolds off for coating. Right now I gota fix a small leak on my pump for the air to water inercooler. Its a bad clamp I hope!! Quote Link to comment Share on other sites More sharing options...
280zex Posted January 14, 2010 Author Share Posted January 14, 2010 XNKE I run a locked dizzy as I don't have a boost retard box installed yet. Mabe go with a Hyfire with btm. Right now my idle is 1k but drops to 900 when i turn on the lights and cab heater fan. Quote Link to comment Share on other sites More sharing options...
yetterben Posted January 15, 2010 Share Posted January 15, 2010 detonation gremlins on 4 5 6 there is a thread at the top of the l series section. I am not gonna lock my dizzy this time around i am actually gonna slot the plate so it retards under pos pressure or just set max timing to 20 and go from there. Quote Link to comment Share on other sites More sharing options...
letitsnow Posted January 15, 2010 Share Posted January 15, 2010 Here's an interesting read about improving gas mileage with a carb.http://www.gofastnews.com/board/economy-green-forum/1228-2-eco-tune-carburated-v8s-fast-accurate.html Quote Link to comment Share on other sites More sharing options...
Tony D Posted January 15, 2010 Share Posted January 15, 2010 Not at a power level consistently to tax the system to require them if all is up to snuff... but if he starts making 5 minute full boost blasts in 5th gear down the interstate... "I realy like my turbo setup but it eats fuel on boost." My personal best with triple blowthroughs was 4.5mpg....daily driving it in commuter duty I was getting 17.5, which was better than the worn-out SU's I had on there to get it to pass smog! "XNKE I measured that cam while at Delta cams with my dial indicator. It does measure .480 lift." If you saw 0.480" lift on the cam, that equates to a 0.720" lift on the valve. Normally gross lift on an L Cam is limited to below 0.434" to fit through the cam towers. If you meant valve lift, that is a normal enough number. If the ramps are assymetric you can have a steep ramp on one side. If you have a symmetric cam, the ramps and total time at lift is far less. L's like assymetric cams. Quote Link to comment Share on other sites More sharing options...
Xnke Posted January 15, 2010 Share Posted January 15, 2010 Good to know they've finally fixed that cam, 280Zex. Mine's still a .454" lift, I'll have to call them and find out about the new grind. Still gotta get on the dyno first to know if i need more cam. Have you thought about going to the EDIS timing system? it's really, really easy, and gives you practically infinite control of the timing. And for about 180$ out the door, and two hours to set it up, I still can't think of anything better for a street/strip car. Since you're running a carb, you'd use a MegajoltLight jr. system; PIP, SAW, Power, and Ground, then a MAP line and you're set! Quote Link to comment Share on other sites More sharing options...
280zex Posted January 17, 2010 Author Share Posted January 17, 2010 Mabe I took my measurements icorrectly. I'm working on a small water leak today. While I'm at it I'll throw the dial indicator on the cam. Also I've learned that when I had the rearend done I shoulda went with 3.54 gearing instead of the 3.90. Make for great smokies though!! I had been thinking about going edis but haven't yet. Quote Link to comment Share on other sites More sharing options...
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