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Let me start out by saying I don't have a lot of money for this build. So it has to be a budget build. Anywhere I can save a little money and add my labor for power, I need to do so. That being said,
I have a 86 and up 350 flat tappet cam block with the 193 swirl junk heads I want to build. I bought the engine from a guy that said it ran good. But it had some sludge in it and had gotten rained in. So I have torn the engine down to the bare block for inspection. The sludge wasn't real bad but there was a cylinder that had some water in it that rusted a fair amount. I cleaned it out ok with some scotch brite (and the rest of the cylinders), but the rust left a spot where you can still feel it a little. It is a standard bore, the ridges are minamal, and the bearings were all ok. I was thinking of just putting it back together with new bearings. What do you guys think? Should I hone it and rering? Or just go ahead and do a full rebuild?
I will be buying a new cam, lifters, and rebuilding the heads after I do a little porting on them and may be put bigger valves in. I haven't really decided what to do about the heads and cam yet.
The engine will go into my 86 Camaro with a TPI set up from a 91 Z28.
Thanks for any help.
I decided to use my 305 for the build because it's in much better shape.
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Last edited by morepowerjoe; 05-10-2010 at 10:16 AM.
Reason: changed build to 305
Could I use the 305 roller lifter stuff for my 350 with like a LT1 cam? My 350 doesn't have the roller set up in the lifter valley but there has to be a way to make it work right?
And could I use the 305 heads to bump the compression up? What would that make it I wonder? I don't know what my 350 stock compression is. May be 8.5.1?
I would definitely hone the bores, as well as rering. Before getting into which heads though, have you considered going with a turbo? If you have the entire TPI setup w/7730 ECM and harness from the '91 Z28, your honestly only a hop, skip and jump away from a decent turbo setup. The only costly part of course would be the turbo itself (and even they are getting pretty low in pricing for a decent one), but the headers, crossover and downpipe are very cheap. Could definitely make some great power with a naturally aspirated engine too, but its so much easier with a turbo. BTW, congrats on the G35, my buddy has an '04 with a Vortech Supercharger, and its a blast to drive....
Thanks as always Rob. A turbo is absolutely an option. I hadn't thought about it, but we have good swap meets around here and I have seen some used. What should I be looking for? I could fab all the piping myself, I do have a welder and know how to use pretty good.
I bought a honer today. But I want to measure cylinder taper before I hone but can't find a bore gauge to rent. I just hate to buy one but I guess I need it. I'm gonna order a bore gauge and some file fit rings.
It definitely don't save any money when you do this stuff yourself when you got to buy the tools. But at least I'll have them for next time.
The xs-power headers for a single turbo application (just the headers, not the crossover pipe) work very well. My friend Paul runs them on his Grand National at upwards of 30-psi, and they hold no problem. You can use the crossover that comes with the setup as a mockup to fabricate a stronger one, because the one that comes with the setup is the weak link (they crack, consistently). Here is where you can get a set from, remember, the crossover pipe is junk (too thin), so redo it the right way....;
Tap an oil feed line into an oil pressure passageway in the engine block behind the distributor to oil the turbo, then dump the oil from the bottom of the turbo's center section into the fuel pump block off plate on the engine (just drill an adequate size hole in the block off plate, and weld in a fitting). From there, you'll want to fabricate a down pipe leading into your exhaust. For the time being, just get yourself a cheap wastegate. There are so many things you can do in terms of plumbing for cold air, as well as an Intercooler setup, you just need to determine where and how you want to plumb everything. If you have the '7730 ECM with the TPI setup, you'll want to run the $59 chip burned closely to your setup (there are a few tunes out there for reference on the $59 website, either that or just get one of them to burn you a chip). If you don't have the '7730, consider the Megasquirt II. I wouldn't go any larger than a T-67 turbo charger, cuz it will definitely get you where you want to go. Since this is a budget build, you'll want to run head gaskets that will give before the pistons do (just until you get a forged setup to handle the boost, then you can run cometic gaskets), because head gaskets are cheaper and easier to replace. There's a little more to it than that of course, but this will get you started on the right path....
Very intresting Rob. A turbo will have to be in my future.
It sucks because I pulled apart the little 305 today and it looks great inside. Almost no wear on the cylinders at all. It's making me wonder if I should build it instead.
It's really strange that no one else has any opinions for me.
Well I need to change the title of this build to "Another 305 TPI Build"
After tearing down my 305 I found out it just had four bad intake valves. I mic'ed everything and it was in really good shape. So I'm going to build it instead and wait to build the 350 when I have more money.
So far I've got the engine tore apart and cleaned everything. Then I did some deburring and head work. Next thing I'm going to do is a hone job.
Does anyone know if I should smooth out the cc area in the head? Would it help anything? And what about painting the inside of the rocker arm area and the lifter valley?
Does anyone know if I should smooth out the cc area in the head? Would it help anything? And what about painting the inside of the rocker arm area and the lifter valley?
Yes actually. If you polish the combustion chambers, it is much less likely for carbon to build up. The reason why this is you ask? If you were to look at the surface of the unpolished CC, there would be sharp peaks, valleys, and irregularities. The exhaust gases, unburnt fuel, etc can more easily adhere to that kind of surface rather than a smooth one. Now granted, you may still have a slight amount of irregularities even after polishing, but much less likely for build up. If you have less carbon build up, you will have less opportunity for detonation, preignition, or pinging. You see.. if you have carbon build up in the combustion chamber, that tend to heat up as you can imagine... so much in fact it can turn cherry red. that alone is enough to ignite your air fuel mixture. So, by all mean, polish those combustion chambers.