Best Head/Intake combo for a 3.4?

[mongo]

I am building up an engine for my Fiero. I am not looking for massive horsepower but am looking for an improvement over stock which is why I would like to add Gen II heads to my engine. Here is what I have to work with:

A daily driven 86 Fiero that will remain on the road during the project.
95 3.4L Camaro Long Block (needs rebuilding)
02 Grand Am 3.4 heads (22K miles)
02 3400 SFI top end from a Monte Carlo
85 2.8 Long Block with unknown mileage
Injectors from a 305 Chevy

My plan is to rebuild the 3.4 short block and re-drill the starter holes. Add the Grand Am heads (after I freshen them up a bit) and the intake (or the bottom intake) and pushrods/rockers from the Monte Carlo. Use the 2.8 long block for the parts and covers to make the swap as hassle free as possible. Sell the un-used parts off-set come of the costs.

Other than the standard pitfalls of the 3.4 Fiero swap, does anyone see an interchangeability issue with the parts I have selected? Will my lower intake need to be machined to fit?

[bszopi]

If you are using the heads from the GA, then there is no reason to even talk about your existing lower intake (as mentioned in your last sentence), and the Fiero intake doesn't match up the the aluminum heads.

[mongo]

Correct. The GA heads have much larger intake and exhaust ports so the iron head intake won't work. I was referring to the Monte intake. I have yet to mess with the lower intake from the SFI but am concerned that it will not have the clearance necessary for the Fiero distributor. I think a little machine work can get me around that hurdle but I am concerned about the angles on the head/intake mounting surface.

Also, I didn't know which of the heads had the better casting, the GA or the Monte heads. My last concern is the cam (no rollers for the 3.4) pusrod and rocker geometry....

Since I am Frankensteining this motor together, I am really looking for one of you guys with MUCH more experience than I have to stop me on one or more parts of my plan with "the water jackets won't line up" or "using those rockers will bend your pushrods"....

And I am aware that I need to use the FWD dished pistons with the aluminum heads....

[Superdave]

yes, you'll need custom pushrods. there are some measurements out there that will get you close enough though, if you need them i can dig them up for you.

the grand am and Monte 3400 are identical, so use whichever parts you want.

i take it that you are converting to the DIS system? if so then use the 3400 injectors, I think Ben (Sappysomething) might have a chip to run that setup. I used to sell them but i'm out of blanks and don't really have the time anymore.


it's nice to see someone using the propper parts, too often people stick with the iron heads and wonder why they can't make decent power. Nice work!

[mongo]

Thanks for the kind words. Since I am new I will give you some background on me:

I used to be a big Ford V8 guy. I've built 351C's and 429's. I've converted points to electronic. I've built a Straight 8 Buick in a 50 Super 4 door. Then I did a couple of 4's (Cutlass Calais, Ford Escort) and the last motor I built was a Chevy 4.3 in an Astro Van with a 5 speed (the shifter was about 3 feet long!). I've done my share of two and four stroke motorcycles/ATV's as well. I know the difference between reed vave and port piston induction.

Then I quit building for a while and started a hobby that took less room in the garage. I spent the last 8 years collecting arcade games. So I own my own programmer and chips as well as an O-Scope and other test equipment.

Now a buddy got me into Fieros. I have been researching engine swaps for the last 6 months. I'll build the short block myself since I am not a fan of motors someone else touched. If it blows up on me... I'll know EXACTLY who's fault it was!

So.... I plan on keeping the distributor ignition and ECM for ease of the swap. The Fiero injectors are 15LB I think and I will need to move up to the 19LB from the 305 to keep the ECM from running the engine too lean. There will need to be some tuning done but that should solve my initial fuel mix problems and get on the road after the swap.

The parts listed in my initial post have set me back about $360 total. Each engine cost $150 running but with a lot or a mystery number of miles and an extra $60 in shipping for one of them. All of the other parts were included with the engine deals or free. As for the rebuild... I will not get away so cheap!

[95Grand-Am]

I don't think you can machine enough off the intake to run a distributor. Like superdave said you will have to change it over to DIS.

[Superdave]

yah, a dizzy isn't gonna happen unless you extend the shaft like one guy did.. but the DIS conversion is much easier and more reliable. Since you have the 3.4 block you are half way there, it's got the 7x crank sensor. If you got the module and coils with it then (i'm pretty sure) there are a few small harness changes and it all hooks right up.

I'd swap in a chip from a Cavalier or Beretta with the same trans type, that will run the DIS system correctly. It will idle rich on the 19lb injectors and your MPG will suffer till you get the tuning done.

Hopefully other Fiero swappers will chime in, i know a few guys around here are running the gen3 engines in them.

[mongo]

I had planned to keep the distributor to keep the swap as simple as possible but I should be able to grab the DIS system off the 3400 SFI motor. Will I need to change the ECM if I use the DIS?

I had planned running this engine with a 4T60 trans to avoid the complications of swapping out the entire wiring harness and ECM...

[geoffinbc]

You can keep your ECM there is a pin out on this site that shows how to adapt the harness to DIS. It is really simple.

[mongo]

So it looks like the DIS may be the way to go. Since there are no screaming objections to the basics of my plan, I guess I better get that 3.4 block stripped down and off to the machine shop!

[mongo]

OK... so it looks like I need to do a lot more research on the DIS. I cannot find the pinout information referred to earlier. I did find this thread exploring the exact subject and it did not end with a resolution:

http://60degreev6.com/forum/f104/replacing-distributor-with-dis-t33507

[mongo]

So I found the pinout for the 7730 ECM and it looks like the conversion to DIS will be a snap. Thank's for everyone's input on this project. I think I have a solid plan in place for this project now. It will be 61 degrees here over the weekend and I'm thinking that will be a great time to strip the block down and get it out to the machine shop....

I'll post pictures of the build as it moves along and I am sure I will have more questions/concerns before it is all over.