Cascade Crew

[Twilightoptics]

So after looking at 60degreev6.com it looks like the 3.1L MPFI is the way to go. 3.4/3.8 stuff is more advanced more expesive etc.

Now I realize I just got Gen II Iron heads from you, but these aluminum fastburns look pretty wicked. Or is that a whole new ballgame.

Looks like they started with aluminum 28cc heads and 28cc pistons in '87. Then when they went 3.1 they had 26cc pistons and increased deck height by 4mm in 89.



Not sure about the cams used, but why did the aluminum FWD motors only make
Horsepower 140 (3.1L VIN T only)
Torque 180 (3.1L VIN T only)

The same as the Iron headed 3.1 RWD motors? Is that because of the intake?

With the aluminum heads can I use a thirdgen 2.8/3.1 intake?

Are the 2.8 vs 3.1 intakes different in terms of flow?


Do I want to start with an '88 block?

[blue89]

Part I


Oh man, you have lots to learn.

First off, FWD never had aluminum heads. This was only offered on the FWD versions. And you are mistaken on the 3.1MPFI as well. The best route to go is the GenIII 3400. +200hp.

Considerations to think about:

-FWD blocks do NOT have the provisions to mount RWD motor mounts to them. They will however bolt to a RWD tranny.

-Aluminum and Iron heads have DIFFERENT pistons

-Distributors do NOT fit on FWD aluminum heads (I say aluminum because the early FWD 2.8's used iron heads until 88 or so)

-2.8 designated blocks do NOT have crank position sensor bungs.

[blue89]

Part II

K. So you are armed with the above problems. Now here's some of the advantages:

Head CFM for Iron head = 160cfm with work
Head CFM for Gen III head = 200cfm with work

Not to mention the aluminum heads have splayed valves, centrally located spark plugs, good chamber design, huge intake ports, d-port exhaust valves, and distributorless ignition.

So here's how you get the best of both worlds for an NA build:

Take a 3.1 block with crank position sensor, KEEP the RWD pistons in the block and put the 3100/3400 heads on it and full ignition system with wiring. If you don't have the CPS bung there are ways to work around it. That should net you 10.5+:1 CR and push you to great hp potential.

[Twilightoptics]

hehehe I know. I know some v8 stuff and how to go fast but this 60º is all greek.


So I should just try to find a running 3400 motor? I don't think I can get the Commander 950 running with an OBDII style ignition. That's why I was looking at the MPFI stuff because with the TPS/IAC/Distributor it's virtually plug and play with the C950.

Horsepower 185 (3400 only, varies slightly between models)
Torque 205 (3400 only, varies slightly between models)

[blue89]

Ya, those numbers are at the stock 9.xx:1 compression ratio. The RWD 3.1 pistons have a .100" dish in them. The 3.1 FWD pistons have a .200" dish! Since the head actually has less CC they made the pistons dish more to lower the compression. So if you put the .100" pistons on the 3400 heads, shabam! Way more compression. You might have to run a thicker head gasket though to tailer it a bit.

Buuuuutt. If you decide to go power added, it might be better to keep the iron stuff cause, well, its iron. Dig through www.60degreeV6.com some more and see what people are doing. I actually have never done this, but I did at one point have the 3100 setup in my garage and was prepared to do the swap. Then I got the LT1.

[91RSVert]

Im fairly familer with the 6/60 as well. As I have had 4 myself, plus maintained 2 others.

First off, what is your goal? Lots of hp, driveabilty, reliabilty, budget, etc.

Next, 88 had some mid year changes made and it depends on if you have an early model, or late model. I would suggest starting with a 90+ 3.1 block.. but if your going to get a new block, up the displacement to a 3.4.

If you want to keep a dizzy, I would suggest getting the supersix heads, have them port the bottom intake to match, then build your own upper like "truelo" did for the fieros. Make that intake hold a dual blade TPI TB like um... whos that turbo 4th gen bird?

[blue89]

*happy dance*

Hey Jay!

What supersix heads are you talking about? I think I remember something about them. Its aftermarket?

A 3.4 would be fun IF you could find one. You CANNOT bore out a 3.1 to make a 3.4 because of the wall thickness. I bored my 2.8 out .060" over and I still had about .250" left. That and the crank and I'm 3.225L.

Jay, would you recommend the iron heads for him? How easy is it to adjust spark advance on the DIS? Is it a single wire like the dizzy setups? He wants to run a Commander unit instead of the stock ECU. So if its hard to control he will want to stay dizzy which limits him to RWD setups.

[Twilightoptics]

Goal is HP on the Cheap. IT's a cheap go fast project. Hense the 60 deg stuff since it's cheap or free and plentiful.

I have a TPI TB. The base is just the usual MPFI base? Someone had mentioned something about making an upper because the design kinda sucks.



The Commander has a crank trigger option but I'm not sure what all it works on. I'll check the book.

[blue89]

If you want hp on the cheap, why don't you get a 350? Stock it has more hp than the turbo 2.8. Then you could do a turbo on the 350! There are people with Cavi's running low 13's with a 3400 block. And your 'vette isn't going to weight in that much less. Is 13sec okay?

[91RSVert]

Parts are not cheap for a 6/60. And plenty.. only in stock form. There is very little aftermarket support, and what is out there is expensive except cams.

DIS, you adjust timing via the computer. I dont know anything about editing OBD2 and v6's. Would need to go to another forum for that. I will learn OBD2 v8's here in a few weeks.

Yes, the upper design on the mpfi v6 sucks (or lacks of sucking ).


Travis, the supersix heads are stock iron heads, redone with bigger valves, ported to hell, new springs, etc.

[Xophertony]

a trujeo intake clone would be awsome. with a tube bender i don't see where it would be that hard either. the dificult part would be to get the runners to shrink as they went down. (you want runners to get smaller as they goet closer to the engine right? there was a big thread about this a while back) but you could always just NOT do that part. i am sure it would still kick ass compared to stock. and if you went with TPI length runners you would still make some decent TQ.

if i were you i would make it with aluminium.

[91RSVert]

ok, if I had unlimited funds and access to everything needed....

FWD 3.4, with whatever needed to make it fit in RWD application.
3rd gen aluminum heads.
custom grind roller cam
electric water pump.
custom made headers
proper pistons.
Multi stage juice

now for the upper part, several ideas:
1. 6 seperate volcity stacked throttle bodys(guy posted on tgo working on this with wave runner TB's).
2. Custom made upper plenium with front facing TPI TB(then add turbo)
3. Custom made upper plenium with dual top mount vortec TB's ran off drive by wire so that the second one doesnt open tell xx specs are met.
4. Do a dual plenium with somewhat stock size TB's, and twin turbo.
5. Machine the top off the base intake, have a mount made for a cobra SC, then heliarc the two together.

[Twilightoptics]

If I went 350 the cons are:
Cost:
A running 2.8 car with FI itself tends to be cheaper than a 350 car.
Weight:
The extra 50horse a 350 will make it stockish form (since no real fundage for upgrades) would be out "weighed" by the weight of the 350 over the 2.8, plus the bigger headache on the install.
Parts:
Probably have to find a carb/intake/distributor should i come up with a block.



I already have a 13 second car.
Cavaliers weigh in around 3300+ lbs.

The Chevette is around 1900lbs stock.

[blue89]

I did a bunch of research earlier on. What I discovered was that the iron heads just weren't good enough. Too many comprimises with this engine. But if you could do a custom intake (not like the truelo) I'm sure you could help it a bit.



Give my V6 cardomain site a good run through. I have lots of info in there.

[Twilightoptics]

2.8/3.1 with a Turbo.

Think that's gonna be the way to go.

N/A with this seems to be too much PITA.

[Dewey316]

3.1 turbo is going to be the cheapest route. You should be able to push close to the 300hp level without much fuss. Its all in maximizing the parts.

Pfff, we can bench race, draw do math on all this crap this weekend. Nothing says fun like reading compressor maps and calculating air flow after 5 or 6 beers.

[Twilightoptics]

Think I'll find a 2.8 and get the thing running. Finish out the rear axle and such then yank the block for 3.1 crank/pistons and make it fresh and put it back together, break it in and add the turbo.

[blue89]

Thats what I would recommend for max poowwaaaa. But keep the iron heads if you really mean to go turbo as you'll need at least 14psi to run 300hp. I haven't heard of any aluminum headed cars running that much.

The crank/rods are supposed to be factory forged and good to 300hp and 7000rpm.

Does your Commander do MAF, SD, or both?

[91RSVert]

The guy with the turbo 3.4 firebird that also did the TPI TB mod. He had over 300 at the tires on a stock bottom end.


I agree on the weight to HP level. My 3.4 in a stripped base hardtop car when running right would outrun this fully loaded vert 350 any day of the week.

[Twilightoptics]

Commander runs SD or Alpha N.

Might just use all the stuff off of my car sensor wise.