262's 85 Fiero SE LX9 F23 swap thread lots of pics

[ericjon262]

Almost done... all that's left is a few diodes, and some misc. connections...

[ericjon262]

Took a break from the harness...





Mocked up the downpipe in 3" PVC, the real deal will probably be stainless.

also got the wrap job mostly finished on the dashboard.

[ericjon262]

well guys, I keep looking at the manifolds I have, and thinking about how they are a really poor match for my engines potential, and I've made the decision to continue onto making a custom set of headers. 1.5" 16ga mild steel, 3/8" flanges, and 3-1 collectors(1.5" in, 2.25 out) I'll probably reduce the 2.25 to 2.00 out of the collector for better velocity going into the turbo, but we'll see once I get come pipe in my hands.

[ericjon262]

Ladies and gentlemen, with the exception of the grounds, maf /iat sensor connector, and final taping, the powertrain harness is complete!

[unchained01]

Way to keep at it !!!!

[ericjon262]

thanks, it's raining here today, so that's limiting me to indoor stuff/research...

[TGP37]

As for turbo headers, you will see more power sooner if you pipe the primaries with the shortest distance possible to the turbo. Equal length primaries will produce more power but smaller diameter, shorter primaries will get you into boost faster. Making even yet more power then equal length headers would.

Something to consider, I did a lot of research into turbo headers. For turbo engines, smaller diameter primaries will get you into boost quicker due to increased velocity. But not too small, just a little bit smaller then optimal for n/a version of your engine.

Not only will you hit boost sooner, it will make the headers far easier to build and easier to pack in there.

Haven't built mine yet though.


Well done with the wiring, you are moving along at a good pace.

[ericjon262]

I'm looking at 1.625" 16 gauge tubing, I was going to go 1.5", but the bigger pipe will be worth more then I get the heads ported. I'm planing on 3-1 equal length primary tube, with a 2" outlet from the collectors to the turbo. I feel like this setup will complement my cam and heads the best. The routing will be similar to the rear header I had previously made, but ditched because of QC issues.



most of the parts will be from cone engineering this time around as they offer 16 ga 1.625 tubing, and 3-1 merge collectors.

http://www.coneeng.com/exhaust_system_kits.html

I also found these little beautys that ought to make life easier.

http://www.vansantent.com/welding_accessories/ice_clamps.htm

Edit:

here's a direct link to the clamp manufacture's brochure

http://www.icengineworks.com/Catalog2012Ed2FullVersionLR.pdf

[TGP37]

It's your call, just saying, I wouldn't go equal length with a turbo on a v6 engine. It's a proven concept that works well with turbos. The only advantage to equal length for a turbo is a little more power pre-boost. But again, if you spool up sooner you can make even more power.

Header design for N/A versus Turbo are two different beasts.

SuperDave mentioned stepped heades once, where the initial primary diameter is small for velocity, but as the gases expand the primary steps up to a larger diameter and the wall acts as an anti-reversion wall. Similar to the exhaust port being smaller then the manifold it dumps into.

If you properly tune the equal length for pulse tuning, with a divided turbin inlet, you "can" achieve faster spool, but all that extra pipe loosing heat and a lot more volume to pressurize, it can be lost just as fast.

Increase velocity, reduce heat loss, reduce header volume = fast spool up


I only mention this because you seem like the type that loves to perfect what you build. Header construction is a science in it's own.

[3400-95-Modified]

Equal length on a Subaru makes it sound like a Honda.... I hate equal length... LOL

[TGP37]

Also wanted to point out about headers for these motors......

I can't say specifically for the 3500 but on the 3100/3400, the exhaust pulse does not leave the block perpendicular to the header flange. IIRC it was 15 degrees off horizontally, so welding the primary 90 degrees to the header flange will create a 15 degree kink.

However you approach the design, look and see how your exhaust ports fire out. Actually compensating for this might yield good results, because 15 degrees is disruptive to a smooth flow.

Thought I'd pass that on.


Edit: Good read on Turbo Header Theory from Garret Engineer

[ericjon262]

If you properly tune the equal length for pulse tuning, with a divided turbin inlet, you "can" achieve faster spool, but all that extra pipe loosing heat and a lot more volume to pressurize, it can be lost just as fast.

.... .....

[ericjon262]

well, the slope just got slipperier... I'm getting a set of pistons and rods!

[TGP37]

A good idea for the boost levels you want.

You going to use ARP rod bolts and ARP main bolts? Good to use when tossing more power at them.

While your down there a crank scraper would compliment the build nicely and are inexpensive, installs easy. Keeps more oil in the pan instead of wrapping around the crank causing parasitic loss of power.

[ericjon262]

I don't think there is a scraper that fits the 3500 is there?