Should I upgrade my heads?

[Joah_from_Alberta]

If I have to replace my head gaskets, should I upgrade my heads?

I have a rear-wheel drive 3.4L in my Jeep Cherokee. It is carbureted.

What are my options for swapping to a better head? Can I use the 3400 or 3500 head?

Thanks,

[bszopi]

You are stuck with those heads unless you get rid of the carb and go with EFI, in which case you are looking at a lot of other things that would need to be done, like swapping ECMs, wiring harness, etc. There are no carb manifolds for the aluminum heads right now, therefore really leaving no options.

[Joah_from_Alberta]

What about building a carb-adapter plate?

[SappySE107]

that would be interesting. You can cut and weld and make something like that work but you still have a manifold setup that isn't designed for wet flow, and power will take a hit. We need a custom made lower for such a conversion.

[60dgrzbelow0]

In a moment of cool serendipity...Here is a Chevy S-10 Blog that features non other than our very own Geoff Moore (betterthanyou) helping out on this very subject... Ben... Since the motor involved on the S-Series mod was a 2.8L engine...would this manifold still work in this case... or does this image portray a V8 manifold?

http://forums.s-series.org/viewtopic.php?f=14&t=23079

[SappySE107]

That is still for iron heads.

[60dgrzbelow0]

Thanks...

This site shows a 3.4L engine shoehorned inside an MGB...and other than the odd "potato" style intake...in the absence of switching to aluminum heads...would there be any HP boost from going with this Iron Head set up?

http://www.britishv8.org/MG/CraigRoush.htm

And an interesting 3.4L Engine discussion...

http://www.mgexperience.net/archive/3_4_intake/377574

[bszopi]

That's the exact setup he already has. A 3.4L with a carb.

[60dgrzbelow0]

Hmmm... I had the impression he had a two bbl (Don't know what the stock Jeep Cherokee engine comes with) and wanted a bump in HP ...one way or the other, starting with his heads ...but now with that being out of the question... I was curious to know whether a 4 bbl would give him anything at all here... other than less gas mileage.

[bszopi]

He has a potential head gasket leak, so he was just asking if while he had the heads off, if he could swap to different heads which would add a performance gain.

[Joah_from_Alberta]

So maybe my next viable option is to ditch the 3.4 and go to 5.0 Chevy. Good gas mileage, same torque as 5.7L. All I need is to weld some brackets under my jeep. I'm just not impressed with my options with the 3.4L I've put a lot of effort in the last year to get this motor to perform and now in the dead of winter it decides to bleed prestone with no option to upgrade other than another harness transplant and potential injectors ... the merry dance we weave ...

Cheers,

[geoffinbc]

If you after ultimate power a V8 would have been a better start. The 3.4L is simply the most cost effective swap you can do for more power. The fact your leaking coolant simply means you have and old or new engine that was most likely overhead at some point. These engines do not have head gasket problems.

If your after more power then you can clean up the stock head castings and gasket match the intake. While your in there you can throw in a COMP cams cam kit and roller 1.6 rockers and you will get a healthy increase in power. With a 3.4L a 4bbl manifold and a 390 CFM carb would be in order. A stock 2bbl wont really cut it especially if left un tuned.

[Joah_from_Alberta]

Yeah, I am considering replacing the head gaskets. Now when I open the engine, will I be able to see if that was the problem? That is the ultimate question, as I am loath to put in a comp cam if the block is no good.

The guy who sold me this engine put the heads on himself as originally it was just a short block he bought.

Just thinking about it depresses me. I want to keep two thoughts in mind: be patient, and don't dwell on negative thoughts.

Cheers,

[Joah_from_Alberta]

Alternatively, I did find this add in the paper:



Date Listed 19-Jan-11
Price $300.00
Address Drayton Valley, AB, Canada
View map
Make Chevrolet


I have a 3400 series out of a chev venture minivanfor sale already out and ready to go the motor and tranny only has a 110000 on it great deal if needed would like it gone asap

This ad was posted with the Kijiji Classifieds app.

I think this is the engine: http://en.wikipedia.org/wiki/GM_60-Degree_V6_engine#LA1

[Joah_from_Alberta]

If I were to replace the iron heads with new iron heads, and camshaft, and intake manifold, does anyone know where the best place I could find these?