After what seems like years, the car is running. Many gremlins along the way along with so many little things that kept popping up.

Base car:
89 gta, miniram 383, 10.5:1 comp, 1 3/4 headers, mufflex 4 inch exhaust, yank ss3600 converter, 3.73 gears in stock 9-bolt, 230-230 .600-.600 107lsa cam, 36lb injectors. Car ran best of 11.60 @ 118 1.72 60ft on motor, 10.39 @ 131 1.58 60ft on a 175shot a few years ago with et streets.

http://www.superchevy.com/how-to/eng...on-conversion/

http://www.superchevy.com/how-to/tra...tiac-trans-am/


Just added to the car:

used vortech t-trim blower with 10 rib pulleys
vortech sbc universal carb bracket set and manual tensioner
vortech 10 rib 7.8 crank pulley and serpentine spacer
ebay 31x12x4 intercooler
ebay 3 inch I/C piping kit
80lb injectors
vortech mondo by-pass valve
boost guage
innovative AFR gauge

I got alot of good info from DAVECS1's thread about his vortech install, like drilling the sbc carb vortech bracket mounting holes 1 inch lower to get the hood to close on the firebird's. Dave was using a carb, so the alternator mounting on the universal sbc bracket was not an issue. On a miniram car, the alternator sits too high and the bracket needs to be clearanced to get the alternator low enough to use the stock serpentine belt.

Changes needed to make this bracket work on a miniram car:
-Drill blower bracket mounting holes 1 inch lower
-grind the hell out of the top of the bracket that connects to the head and holds the blower bracket
-get the thermostat housing welded with a new outlet to avoid interference with the serpentine belt

Finishing off some little details tonight, like sealing the timing cover to oil pan to stop an oil leak, changing a water pump hose clamp that went bad, etc.

Driving around the street with a base tune, I only pushed it to 2 pounds to get the fueling right. Was getting AFR's in the 13.5 range before I played around with the tune and now it is around 11.77 AFR. I have another tune file to load tonight which should get the AFR's to the commanded 11.41 range. I am tuning using EFI live which has a boost timing and boost ve map. Timing is real conservative at 15 degrees base timing with 5 degrees being subtracted over 1 pound for a total of 10 degrees timing. I am keeping it to 6-7 lbs for now.


future parts to buy and install for more boost:

-more boost friendly cam
-meth kit
-2 walbro pumps with bigger feed line
-modified miniram fuel rail (stock miniram fuel rail is said to be good to only 650 hp with the divider in the rail, this needs to be drilled out and -8 fittings welded to the fuel rails to get more fuel, TPIS will do this for $150 or so)

I have dyno appt on tuesday to tune it. Will leave the 3.47 pulley on it and tune on pump gas to about 6-7 lbs for a start. For more boost there is a gas station about 20 minutes away that has sunoco 260 gt plus which is 104 octane unleaded. I can also run leaded gas, as i have the o2 sensors turned off and I am running in open loop speed density mode if I find some C16 for cheap.

Looking good some more motor pics please.

Nice. When its done will you be taking it to any local car shows? I live in Fleming Island would love to see it

Nice! Few lbs of boost can stay closer to low mid 12's to 1 air fuel. Once get up over 5 it can start getting richer

Looks good

Look great! If you don't mind me asking. When you were spraying the 175 shot with 10:5:1 compression, did you need 100+ octane? Or were you ok just retarding the timing?

BJ, sounds pretty good man. Do you have a blow off valve? Good luck on the dyno Tuesday. I got the rotating assembly back, but still saving up the cash to finish the motor.

Should not need race gas on something like that. Mine was 11:1 and sprayed 150 on 93 oct

Nope, 93 octane. I have friends who have sprayed 250 on 93 also with no issues.

The blow off is really a by-pass valve on a blower, it is in the passenger battery tray area. At idle it is open and releasing alot of air. It closes once you go past 0 and into positive pressure in the intake.

Just spent about 2 hours driving around and tuning, and the 3.47 pulley only gave me 4-5 lbs of boost. I switched to the 3.33 pulley and still only got about 5 lbs, so either the belt is slipping or something else is going on. I

The manual vortech belt tensioner isn't the best, it's hard to get the belt tight with the limited space. I might have to look at using the serpentine automatic tensioner.

With the air temps at around 35 degrees the iat temps were about 66 driving around, and from a short blast in boost, went from 68 to 73, then back down as I drove around. Not sure that is good for an ebay intercooler? when it gets hotter outside, I have room for 2 small 12inch fans behind the intercooler and in-front of the tranny cooler to keep the temps lower.

You wont know how well intercooler works til you do a full pull. I wouldnt expect much rise in temps on those boost numbers. Higher boosts you start to see how effective they are.

probably belt sip. what rpm are you running it up to in order to see 5lbs of boost? where is your boost gauge hooked up?
are you sure you have all the brackets since you bought them used? if you dont have anything on the back side of the bracket, you might want to consider adding a support back to the head or block to keep the blower from trying to nose over when its under load. that would make the belt slip and or jump off at higher rpms. i would think a spring loaded tensioner would work pretty good with a 10 rib setup. a manual tensioner would be more for a cog belt setup where you dont set it all that tight or an 8 rib setup where you are trying to get the belt guitar string tight and the tensioner will have a loading adjuster bolt on it that you can turn to tighten the belt before locking it down. -with that setup you would want an idler arm running between the crank pulley and the blower pulley to handle all that extra loading of the belt. kurgan sells them.

I am running it to 6000 but I lowered the shift points to 6000 for tuning. It was cold last night and the tires were spinning so the highest rpm I saw was 5700 on the logs. Boost Guage is teed into the line from the intake to the fuel pressure regulator. The brackets and tensioner I bought new, the blower and mondo are used.

I talked to justin87gta and he said I need to use a breaker bar to put tension on the tensioner to tighten the belt. I will see if I can get some help in tightening this thing and put the 3.47 pulley back on for now.

i would figure up around 8-10psi with that setup. breaker bar will indeed be needed to get some tension on there. problem is, its hard to get any accuracy with doing that. you could be REALLY tight or kinda tight. a bolt driven tensioner would be a good idea if you can swing it.

http://m.ebay.com/itm/181464551482?nav=SEARCHMaybe I should try one of these manual ebay tensioners like the one above.

yea something like that would be a good thing to have. also i would bet that intercooler will drop some pressure on the engine side by a decent amount. you might try checking boost pressure before the intercooler also to do a comparison. many of the guys running the ysi in nmra didnt run an intercooler at all with better results.

I used a breaker bar and put some pressure on the tensioner this time. Put the 3.47 pulley back on and I got 7 lbs on the Guage but 6- 6.5 in the data log or 145 kpa.

I will tighten it some more after I drive it more.

This is why i like turbos lol

The car looks like an animal!

Hey orr, you are using efi live right? Have you ever created a custom auto ve map for the boost ve table? My afr is in the high 10's in some ve cells and instead of manually adjusting these I thought the auto ve could do this.

No its tuned by hp tuners and currently i am not tuning the car. My good friend is handling that now until i buy the software. I'll likely only tune part throttle stuff and idle/startup

I like manual control when it comes to doing ve tables.

Orr is correct, doing it by hand will yield better results. At times some of those ve learn tuning aides add to much fuel or not enough and you'll end up doing by hand anyway.

Dyno results just showed i have more work to do than anything else. I went in there with AFR's from 10.6 to 11.4 and timing at 10 degrees, left with almost 11.5 across the board and 15 degrees timing.

Made 480 hp at 5800 at 6.3lbs but the boost dropped to 4.6 lbs by 6200 with AFR at 12.33. Made one last change in the VE table to get the fuel to 11.50 above 4750 and called it quits and didn't make another pull.

I made a bonehead move and left the socket extension in the tensioner days ago and started driving the car not knowing it was in there, and it ended up taking 2 ribs off the belt and a big chunk off a section of the belt. The belt was fraying and coming apart the more we ran it on the dyno. Dyno was packed and my appt was at 3pm but i didn't get on the dyno until 6:15 so we cut everything short. Dyno guy will give me a break on the next appt cause the dyno software was getting some interference and the #1 spark lead was reading erratically, so no torque number was given.

Ordered another belt and found a dude on the mustang forum that makes those manual screw down tensioners like i have in the pic a few posts above, and he is going to reverse the design for me and send me one. Should stop the belt slipping. New belt should be here on Friday. 1/8 mile track is open this Sunday but it is supposed to rain, so I might get to the track, might not.

I need to order those dual walbro 255 pumps and get a blower cam before I go back to the dyno again.

Just under 500whp sounds good to me to you have a whp number with just the 383 before vortech or nos?

Yeah it made 365 years ago on motor and 500 on a 175 shot. Those are the same numbers gmhtp got years ago, I never dyno'd it after that.

Doesnt seem bad considering all things goin on with boost loss. Next go round with belt tension fixed and blower cam, better tuning, it really should make numbers

I have been playing with engine analyzer with the different cams and it only shows a 10 he diff over my current cam. Not sure if I should believe the software or not.

Any real world opinions on how much power I would pick up with a blower cam? Lloyd Elliott spec'd a 226-239 .565-.575 112lsa cam for me already. I just need to pull the trigger on it.

Not sure on peak power, i would assume 10-20 around those boost levels is possible but the main gains are gonna be in the low and mid range my guess. High overlap of that cam is likely bleeding chamber pressure off to the exhaust side. Wider lsa will offset some of that and should make more overall power across the board.

Longer exhaust duration will help evacuate cylinder so should help reduce pumping losses and improve fill on intake stroke. Reduce any contamination of intake charge from reversion effect from overlap.
Similar concept as nitrous grind. Setting it up to take advantage of the extra mass charge

Had some issues with the belt alignment. Kept ripping the ribs of of belts and found a thread on corvette forum in the c5 section as a sticky about belt alignment using the gates tool. Found someone who loaned it to me and as a result I put some washers behind the blower bracket to move the blower .300 forward. Laser alignment tool lines up good now. Ran the car up to 6100 and got 7.8 lbs. Hitting the track this friday.

Got my dual Walbro fuel pump setup from racetronix, but cash is running out. Does anyone see an issue with me doing either of these options with the ptfe lined braided hoses:

1. Get a -8 an feed line and use the stock feed as the new return
Or
2. Use the stock feed and add a -6 return? line

Thats good news!! I like #1 option on your fuel setup.

Making changes to the tune i noticed that my logged runs showed i was 12:1 afr at 6100 at 7.8 lbs with 10 degrees timing. I read somewhere that you should pull 2 degrees of timing at peak torque for safety. if i do that, I would be at 8 degrees and sometimes at 7 degrees based on the tune pulling out timing based on boost. I need to keep this motor alive at 10.5 compression as long as possible and keeping the rpm down is step 1 (shift points are 6k) but timing was another (meth to come later).

How low is too low for timing if there is such a thing as too low timing? At the track tomorrow I was going to dump in octane boost which should get me 102 octane, then make a pass. Look at the logs and if the AFR is good, then add 1 degree of timing until the mph on each run slows down from the previous gains.

I don't have a roll cage, so I have to run 1/8 mile and get on the brakes at gainesville or get kicked out.

Thoughts?

Went to the track last night and now I have to do a compression and leakdown test to calm my nerves.

Made an 1/8 mile pass which showed the car was lean at 14.27 afr at 6300 rpm at 7.8 lbs. Looked at the data log and added 5% to some areas that needed it and 20 to 25% to the cells that were way lean. Made another pass and afr's got worse, same cell above that was 14.27 at 6300 is now 15.21 afr at same rpm. Air fuels do get down to 11.5 in the 5000 rpm range, but they lean out in the higher rpms, no matter what i change in the tune.

I am glad I ran a can of octane boost and low timing. Timing was 10-11 degrees and sometimes because of the IAT table pulling 1-2 degrees 8 degrees on some runs.

I pulled 1 plug and it looked fine other than the orange color from the octane boost. I have the racetronix dual 255 pumps in the garage, but still need the -6an return line to install them. Car drove fine going home, but I sure hope i didn't hurt anything.

Compression test #'s on all cylinders were between 180 and 190. Dodged a bullet there with the low timing and octane boost.

Need to install the dual walbro pumps in the tank with -8 feed line and maybe get the miniram fuel rails modified to take some AN fittings for feed and return ports.

Could oct booster be throwing off the o2 reading? Do plugs look good for fuel?

If air fuel is leaning out regardless of fuel change in tune then you have lack of supply, which should NOT be the case with dual 255's. Make sure both are turning on and running properly. -8 feed and -6 return is more than enough

Right now i still have the 12 year old walbro 255 pump with hotwire kit installed.

I have the dual 255 walbro kit in the garage waiting to be installed, but haven't ordered the -8 feed line yet, I wanted to install everything at once.

I made 4 runs friday night and in all of the data logs, above 5100 rpm, the air fuel goes lean up to 6400 rpm. Below 5000 rpm the air fuels are at the 11:41 target air fuel, around 5000 to 5100 they start to go lean, like 11:6 and 11:7, then after 5100, they go to 12:1 consistently all the way up to 14 to 15.

Plugs were old and i didn't pull plugs at the top end of the track yet. I can't see a timing mark on the plugs either at 8-11 degrees. I need to install the pumps and line first, then go back to the track and make sure the car is getting enough fuel.

After air fuel's are stable, i will pull plugs at the track and add 1 degree of timing until mph stops increasing.

Oh..... Yeah ofcourse a single walbro isnt gonna do it. They are done at 500 ish whp give or take a few

You are well over that

Yup your outta pump.

What's strange is that the dyno and street runs didn't show this lean condition with as many runs as I made. I could never hook up on the street but the dyno I guess should have showed it if I had made more runs. The track really does load the engine differently.

Yes sir dyno unless a real load bearing mustang type wont load the motor as hard. Generally tune car on dyno and before leAving i pull a deg or 2 timing and add few percent fuel to be safe. My turbo car is even worse. Add 5-8 % fuel and pull 3 deg

Almost done with the dual walbro install. I am using the factory 3/8 vent line as a return line, and using the factory 5/16 return and 5/16 evap line as a vent. I cut some relief cuts in the top of the 5/16 return line.

Are there any concerns with using one hose clamp on the pump outlet barb to the factory pump 3/8 line with one hose clamp? That factory connection doesn't have a flanged connection after I cut off the 5/16 necked down part at the end of the hard feed line.

Anyone had any issue with these lines blowing off with higher fuel pressures?

As long as its tight and has alot of tube inside the hose to give it some surface area to grip to it should be fine.

Just got the miniram fuel rails back from TPIS after 6 weeks. Only charged me $115 shipped for the work, but look at the metal they left inside. Not sure why they wouldn't have bored through the remaining divider and inside each injector hole also. I hope this doesn't cause a flow issue.

I could take them to the local machine shop and see if they could drill through the -8AN opening, but I would be worried about getting all of the metal chips out.

Thoughts? Comments?

Well, that's TPIS for you. All their stuff is over priced anyway just like their Mini Ram's. Looks like they media blasted the rails too.

You could have the local machine shop cut off the newly welded fittings and drill the center out like you wanted or you could just clean up the metal shavings and slap them on to see what happens, because rail has been modded at least a whole has been drill through the enter divide.

But I agree, you wasted your time and money sending them to TPIS. I could have done a better job drilling the the center divide out and having my welder do the fittings.

Did you call them about their work, if so what did they say? Never mind, I know they don't care. All they care about is money!!

Didn't call them, why waste time. All he will say is 'they should work for you'.

Tig welding around here is $125/hour, min 1 hour charge.

It was cheaper to have them do the work, but now I am thinking I need additional work done, so it almost wasn't worth it.

awesome!

Finally done with the fuel system changes. Added -8an fittings to the back of the miniram fuel rails and -6an to the front with an external regulator. Added a 2nd fuel pump in the tank and replaced the old walbro with the rxp255 pump and bulkhead upgrade connector and harness.

Now the car bucks, pops and sputters only when the coolant temp gets to 200 degrees. I made some test hits on the car today pulling fuel out and trying to get the air fuel right. The coolant temp was 165-180 on those test hits.

Not sure if my issue is related to my fuel system change or not, but it's the only thing i changed on the car. I don't get any pressure when turning the gas cap either. I know i got pressure before I added the 2nd pump.

I made some slots in the factory return 5-16 line in the fuel sending unit to be used as the vent, and that line is going to the factory white canister thing behind the wheel well. The old evap port line is run to a 5-16 hose and just open vented behind the wheel well.

Any ideas on what is wrong? I am thinking I should be getting a pressure release when taking off the fuel cap? Fuel pressure at the regulator is stable even when the car is bucking and sputtering, but the air fuel guage goes all the way lean up to 20:1.

With the evap line open there won't be any pressure build up in the tank. Note that some folks put a small engine fuel filter on the end of the line to prevent bugs and such from getting into it and/or the tank.

Not sure about the fuel issue, although it may now be so rich that it is misfiring. Spark can't light off the mix.

RBob.

I have a theory I will test later today, I have the -8an fuel feed line y block right behind the driver's side cylinder head against the firewall. I think that is what is causing my vapor lock issues. It is about 1-1/2 away from the head right now. I have a reflective heat starter shield that I never put on my starter that I will wrap around the y-block to shield it from the heat.

I forgot that I still have the carbon canister tucked in the front fender of the car. I will hook back up the evap line from the tank to the factory hardline and see if that gets rid of the gas smell. After you drive the car and park it in the garage, the smell of gas is horrible.

I've added canisters back into cars I bought that were missing them. Mostly for the same reason, keeps the stench of fuel under control.

Be sure to put a check valve in the purge line between the engine and canister. The part number for the one GM used is: 14047619, still available but a little on the pricy side. GM also used them to isolate the HVAC, cruise, and EGR vacuum from boost.

RBob.