Firebird 3.4 to 3500 swap

[Guest]

Seeing that hydrolic lifters have an adjustment range around .200 inch I think the small difference caused by a head gasket or angle of the pushrod can pretty much be overlooked except under the most extreme cases. I think you are way over worrying the problem. Larry

What? .2" (just shy of a 1/4") adjustment? Where are you getting this from?

Pre-load on the 660 hydraulic lifter is between .020 and .040, that's .02" difference, about ten times smaller than the range you suggest and is why each custom rebuild needs to measure for proper pre-load and valve train geometry.

I've been playing with these engines for 16 or 17 years now, I've taken short cuts, and done it right. Doing it right has always produced the best results. I've been able to use stock pushrods sometimes, other times, I haven't.

This is not something that I feel can be overlooked or left to chance. I'm sure many others would agree me.

[Jawz]

Ok i have another question, and its probably a stupid one at that lol.

This time its about the thermostat housing. There is a hole on right right side of the thermostat housing on the LIM, is that like a bypass port or what is that exactly for? and is it necessary for my swap, or can i just block it off some way?

[1988GTU]

Bleeding air out. It should have a brass fitting containing a brass screw.

[Guest]

Ok i have another question, and its probably a stupid one at that lol.

This time its about the thermostat housing. There is a hole on right right side of the thermostat housing on the LIM, is that like a bypass port or what is that exactly for? and is it necessary for my swap, or can i just block it off some way?

Is this the 3500 LIM?

If it is, that would be where the heater line originally connected.

When I did my RWD hybrid swap I instead connected the heater return to the tube that passes under the UIM attached to the LIM, and then threaded the other hole for NPT, IIRC it was 1/2" NPT and used a bushing to install the CTS there.

[Jawz]

Yes it is the 3500 LIM

i planned on using that tube also for my heater line ... no point in going through the trouble when i can just cut the line and move it over to connect it.

[Jawz]

Can anyone who has done the 3500 swap show me some photo of theres? i'm trying to get an idea for running the fuel lines, getting the t-stat housing out of the way of the belt, and finding a way so my alternator isn't so close to the valve cover.

[Guest]

I can post some pictures of my hybrid swap, they might help...

[Jawz]

If you would please, that would be very much appreciated.

[Guest]

This was back before digital cameras were on every cell phone, and cost less than a few hundred dollars, so the picture quality is lower than usual...







After a while I changed the FPR, I was never really happy with the MSD FPR I had, so I modified a stock regulator, and moved some stuff around:



I was hoping I had some pictures of the fuel lines, that I ran up along the side of the block and in front of the left head and to the fuel rails. I don't think I really have any other pictures, at least none uploaded.

[Jawz]

Oh no your fine, what you have there is pretty much what i needed.. i didnt know you could fit your FPR there, that will make things alot easier for the fuel rail and take away most of my problems.

Also did you leave your Coolant Temp sensor in the original spot on the cylinder head or did you end up moving it to the LIM?

[Guest]

The CTS was pretty close to stock position. I actually used the 3100 top end. The 3100 and 3400 had the CTS in the lower intake, just below the thermostat. In the stock configuration, the CTS was to the right side of the t-stat housing (with the engine in a longitudinal position), and the heater hose return connects on the opposite side. To simplify hose routing, I drilled out the CTS port to accept a threaded nipple that would fit the 5/8" heater hose, and then used a bushing in the original heater hose port to put hold the CTS.

I actually plan to modify my 3500 lower to have a similar set up, when it comes time to install my 3500 in my car.

[Jawz]

Alright, well i got the CTS re-positioned, i have to either make my own bracket for the alternator or adjust it so it goes to where my A/C compressor was.

But i have been wiring everything back up and ran into a problem with my fuel injector wiring harness, its not the same end that connects to the Main wire harness, does any one know any way of swapping, or fixing to get it the right one?

[caffeine]

As for the injector wiring harness you can use the connector from your old harness and splice it in. Otherwise you can splice the connector from the other side of the new harness in.