L67 F-bird

[Gutless]

Re: L67 F-bird

I really need to get a 3200 ish stall converter in it, thats what is killing it. 60's were worse than the old setup. Plan is to get the walbro 255 in sometime this winter and get a 2.8 or so pulley on it. Ive got 60's so theres plenty of room for E85 too. 5 PSI more, 4 more degrees of timing, and a better 60ft should get me low 13's if not high 12's.

But this might be a bit down the road. I need another project that I can winter drive and found an 88 AMC Eagle I want to LS swap so ill have to see how the cookie crumbles. :)

[Need4Camaro]

Re: L67 F-bird

I really need to get a 3200 ish stall converter in it, thats what is killing it. 60's were worse than the old setup. Plan is to get the walbro 255 in sometime this winter and get a 2.8 or so pulley on it. Ive got 60's so theres plenty of room for E85 too. 5 PSI more, 4 more degrees of timing, and a better 60ft should get me low 13's if not high 12's.

But this might be a bit down the road. I need another project that I can winter drive and found an 88 AMC Eagle I want to LS swap so ill have to see how the cookie crumbles. :)

Read my thread and be prepared to sell your Firebird for the funds to LS Swap any car... it looks easy and straight forward from the outside only :P

[Gutless]

Re: L67 F-bird

Yeah, it wont be cheap but it should be affordable. Theres $650 complete pan to ECM 5.3's pretty local to me, hope I can get a package deal with a trans and T case for $1200. Have HP tuners, can do all my wiring.

Most of the expense goes to fuel system and hose. Bosch 044, vette regulator, 3/8 line from tank up.

Getting one of these for guages and not even running stock tach ect.
http://ultra-gauge.com/ultragauge/index.htm

Notch a stock truck pan, truck intake probably will fit since an inline 6 fits no problem. Get driveshafts built, AC and heater. Have about half of the exhaust parts I need.

I figure $2000 is realistic. $3000 for a 4wd winter car with 300 hp should be more than reasonable.

[Gutless]

Re: L67 F-bird

Was going to winter crash the fireturd this year again but I decided I didnt want to get stuck in parkinglots. Bought a durango with a blown motor and overhauled it.

Back in November the firebird quit. Dead miss on cyl 1. Has spark, compression, and changed #1 and #3 injectors to rule out a stuck injector. Still not firing on cyl 1. I think theres a wiring/ground issue in the injector side of things. I even changed known good coils and changed the ICM and didnt do anything. Been too cold to want to spend the time to fix it so it sits in the garge.

Hopefully this spring Ill be able to look at the harness to see if the ground wire from the injector to the ECM is chafed, which I think is the culprit. There was gas on the plug and I know it is getting spark since I hooked up a timing light and it is firing good. Probably just flooding the cylinder out.

[Gutless]

Re: L67 F-bird

Did a little diagnostics on why it was running so bad. Found no compression on cylinder 2.

Resulted in this,


Took 2.5 hours, dropped outta there!


Yep.



Broken ls6 valvespring. Stuck weather im going to change out just that spring and button it back up or get a set of new not ls6's.

[ssms5411]

Re: L67 F-bird

That sucks. I wouldn't go with the Ls6s they have a higher seat pressure than comp 105s so I would go with comp 105's.

[Gutless]

Re: L67 F-bird

Comps are mexican made now and the quality went way down since. Ive heard they are even worse.

Thinking about some 105 crows. ls6's are 95lb seat.

[ssms5411]

Re: L67 F-bird

Crow would be good. Their only .550 lift though. The LS6 has a higher spring pressure compared to the comp 105s and the 105lbs are good for .600 lift just like the 130s. It was my mistake I thought it was seat pressure but its spring pressure. I've had good luck with comp so far. Thats with 105 and 130 springs, OER lifters, rocker arms , pushrods, and cams.

[Gutless]

Re: L67 F-bird

Im only running an s1x so at .514 and .526 they should be okay.

Im really tempted to just put another ls6 in and be done with it. Saves me $100 and an hour of swapping the springs over. I actually got these for free so im not that mad about it. Just not sure if all mine are cracked or I just got a random bad one.

[Gutless]

Re: L67 F-bird

Well screw it, im just throwing in another set of new ls6.

[htmabe]

Re: L67 F-bird

Valve springs can be tested I do it all the time. Speedway sells the tools for it. The best one tests the springs out of the head on the bench. You would be surprised at the results with brand new springs prior to install. The cheaper the spring the bigger the surprise. The other one is used while the springs are installed in the car , I have both and use both. With new springs you should test seat pressure and record each number to corresponding cylinder and each spring should be within 5% of each other prior to install. Once that test has passed test them installed and record cyl # intake and exuast. After break in the spring pressures should and will drop 10% and level off. Test for this and record and check your new spring pressures. From that point if any one spring pressure EVER drops an additional 5% your done with the ENTIRE set of springs. Replace all and start the entire cycle over again. That's one way to fight back " the ticking time bomb" effect. I've been through 7 motors in ten years, all failures were through the valve train which were then traced further back to a spring or 2. This last motor is on it's 3rd yr which means it's outlasted the other 6 by 300%. I would have blown it too 4 times with out the procedure described above. Sounds like a little bit of a pain in the rear but like anything else after awhile it becomes just another procedure. Also like anything else you get good at it and can be performed in about 45 minutes start to finish clean hands. I don't do it every race but after the third time at the track I do it. Keep in mind this procedure is quicker cleaner and cheaper than any motor replacement. Also keeps the car going it's fastest with little or no down time.

[ssms5411]

Re: L67 F-bird

Im only running an s1x so at .514 and .526 they should be okay.

Im really tempted to just put another ls6 in and be done with it. Saves me $100 and an hour of swapping the springs over. I actually got these for free so im not that mad about it. Just not sure if all mine are cracked or I just got a random bad one.

Thats true if your not going past the .550 lift your alright. And if you use Manley or ZZP modded retainers they'll save you even more on lift.

[Gutless]

Re: L67 F-bird

New ls6's are ordered
Head studs are ordered
New gaskets are on the way

Dropped the head off at my machinist and he noticed that the valve seals are tore up, looks like the rocker is contacting the seal.

Not sure if my seals are a bit thicker than factory or what but hopefully we will find out!

[WarShrike]

Re: L67 F-bird

You're cutting it close.

.525 intake
.528 exhaust

That's max lift on stock retainers and seals. .530 will damage them. With the irregularities in the lift from the stock rockers, you could have actually approached that value or exceeded it. I vaguely recall stockers ranging from 1.6 to 1.65-ish. Gotta love GM quality control.

If you're running viton seals and modded retainers, it'll give you a little more room.

Anything more and you need to have the valve guides milled to allow more lift. I believe mine are milled to handle all the way to .650"

[Unitt]

Re: L67 F-bird

Just wanted to say I'm lovin' this thread. When I bought my bird I immediately wanted to do this swap. I'm in the process of getting funds for this right now. I'm glad you decided to post your build I'm sure it has helped a lot of people with this time consuming swap.