Project update

[NinEFivEFourOH]

Hey all.

Been researching and brainstorming steady for the past few months about performance and mods for the 4.6 going into my 95. Things look promising and have been coming along nice.

If anyone doesn't know, I'm swapping in a 96 4.6 into my 95 Aurora, complimented by worked heads, CHRFAB 272 cams, lightweight bottom end parts, intake, TB, true duals, blah blah blah and now I am most certainly aiming for headers.

I am at the build/planning stage still, but everything else is in place and I believe (other than maybe a better intake design), the headers are the last bit.


Here are just some of the parts I've accumulated for the build. Pictured are Eagle Rods, ARP Headstuds, both Timesert kits, and some rare .020+ Wiseco Pistons. I came across a companies last set of these pistons and bought them up. I decided to go with a lighter weight reciprocating assembly for several reasons:
A: It's a rebuild, I wanted to use as many new parts as possible.
B: Less weight to move makes longevity greater
C: I've weighed these parts and have found that the rods and pistons offer 3lbs in savings over the stock lower end (not much, but every little bit helps).

Onto the header project...

I've been racking my brains to try and figure something out. My main goal here is a departure from the dreaded crossover pipe which is known to be the choking point and the killer (performance wise) for these engines. I've decided that a better design is possible, and I'm going to try it. If successful, this will mean several things:
A. Performance will be helped (duh)
B. In the event that the bottom end needs to be accessed (oil pan and whatever else is inside), it can easilly be done by removing the new crossover pipe, instead of having to remove the transmission or engine totally.

While performance is a main objective, my main concerns for this design are quality (best materials, best welds, best construction), and practicality (good design where the new peices are easy to install and remove). I believe that if this is successful, this could be a hot item if it can be made cheap enough. If I can pull off my design and have my own made, I plan on having a duplicate made for reproduction purposes, and sale to anyone interested. Anyway, here is what I have found from examining N* cars at a junkyard.


That's the Aurora bottom end. I haven't tried yet, but I examined the plate covering the crossover pipe there, and it looks as if it could be flipped upside down, to create more clearence for the new pipe.






The rear manifold should be the easy part...Plenty of space back there (especially if I can redesign the crossover pipe, re-routing it entirely under the engine/trans).




The front manifold will be the challenge, space is somewhat limited compared to the rear, but through engineering and brainstorming it can be accomplished.



More in the next post...

[NinEFivEFourOH]

This is the front end of a N* Cadillac (Deville, or STS I can't remember, they're pretty much the same). I was glad to see this car like it is for several reasons.


Obviously, the brace on the manifold and engine mount are not there, so it is somewhat similar to the space available in the Aurora engine bay to work with... (Those are 95 (and earlier?) manifolds by the way, different from 96+ pictured above in the Aurora. I am unsure of differences (+/-) wise between the 2 and do not understand the reason for change.


While they may have to be shorties (who knows, maybe I can rounte the 4-2-1 or 4-1 design farther underneath the engine... they can be made.



Looking underneath of this car, this floored me:

Never seen that done before, but I was glad that whoever did it, did it. You can see how thin that crossover pipe is, how much of a restiction it is to the exhaust. Good riddance if I can...



Thoughts, opinions? (I know you old-timers will say let well-enough alone/it's a Luxury car, it doesn't need any more power). I've heard it, I know you're going to say it, don't bother.

[electrostatictommy]

If you look at this link:
gmpremiumv.proboards.com/index.cgi?board=fiero&action=display&thread=13&page=1

You'll see how this guy made a great 180 degree tuned header system for a Northstar Fiero transplant. I think you could use this design for your engine swap. Let me know what you think!

Here's what it sounds like:
www.streetfire.net/video/fiero-northstar-32v-v8-first-start_723761.htm

[Deleted]

Now are you looking for plug and play with this setup? IIRMC and I do, the 95's had different engine parts. So therefore different electronically monitored devices. Also the 95's ran on an OBDI setup where as 96+ ran on OBDII. I am no electrical whiz, but something tells me you will encounter problems when the computer can't pick up on said electronics. I.E. EGR valve. Which, IIRMC the 96+ did not have. I am not, by any means, dismissing your project as useless. I am just intrigued as to how this setup is going to work. Have you considered swapping PCM and ECU for a 96+?

[NinEFivEFourOH]

Yeah I've seen that video before, crazy stuff. It might help a little bit, I forgot about that, thanks.

As far as differences, that's easy enough to deal with. Cut and splice where needed, but I don't think much if any of that will need to be done. Most everything different will be swapped off the old motor, I'd rather modify for the car, then modify for the engine... I've thought about doing an OBD2 swap but an unsure if that's even possible as OBD2 cars have body control modules and all that stuff... too much work, especially when Wester's can tune this stuff.

[aj]

Good luck with the project!

[postalc38]

I'm still trying to figure out how someone got that oil pan.......

[NinEFivEFourOH]

Yeah that was wild to me, I still can't believe it. I was like "holy *******..." when I saw it. But as I said I'm glad that they did it, allowed me to finally see what the inside of the crossover pipe looks like, just how thin/restrictive it is.

I am very confident about how this will turn out.

[turbokinetic]

Neat pictures and awesome project! Looking forward to seeing this come together!
David

[NinEFivEFourOH]

Got my heads back from the shop. I think he did a good job and was pretty reasonable for what all he did. Ported the exhaust side, 3 angle valve job,blended the bowls, resurfaced the heads and put them all back together with stiffer springs and all new parts for $600.
















Heads with header flanges.

Pretty excited to get them back together, need to buy new lifters... @ 9.50 a piece and needing 32 of them it's not gonna be cheap! Cool thing is they're the same as the Quad 4 lifters... :rolleyes:

Finally got the car to my new house, it's been sitting at my buddys for over 2 years and after I finish some renevations in my garage I'll get it in and start taking it apart.

[ntrenn]

Looking sweet. We're excited as well...

Quad4 lifters, huh? Good thing they killed that engine so we 2Gen folks didn't have to use them too...

[NinEFivEFourOH]

Hey hey easy there... I've got a 90 Beretta GTZ with a quad and it's been really good to me, it's my baby..

[lanceslambos]

since your doing so much in the way of adding power to your aurora why not go ahead and get that 4.6 extruded and honed? that's another 10 hp roughly ya know. the next to last picture illustrates pretty well why it could use it.

[ntrenn]

Sorry - didn't mean to offend. For its day the Quad 4 was a pretty sweet package. Worked on qualifying the 5 speed that went into that way back when.

The lifter design must have been pretty bulletproof if they used it as long as they did - it was just a high friction design that hurt the CAFE ratings.

[NinEFivEFourOH]

What do you mean by extrude and honed? Had the intake and exhaust on the heads done?

From my knowledge they say to leave the intake side alone; the patterns/coarseness has something to do with fuel mixture/fuel flow and such... the intakes are already pretty big anyway.

Are you saying to enlarge the exhaust ports more? Or smooth them out? They're already pretty smooth and to go any larger would hurt exhaust gas velocity; this porting was done to be in tune with the cams I'm running and to maintain a good powerband.

From what I know about E&H it's pretty pricey... I've put a lot of money into this already but I'm not sure where the gain would be on that, especially since it's pretty expensive.

[shelbyracing]

I'd be a little worried about the thin cylinder walls, going .020 over. The head studs will absolutely help though.
Also I've done some extensive research on 4.0, but if the 4.6 is the same lower end it was built to withstand 10,500 rpm's. The IRL motors only changed the heads. So with stiffer springs I'd raise the rev limit to 7,500-8,000. I bet you could get 450-520 hp with that many revs, as long as you build the intake and exhaust to handle that kind of flow.
The IRL engines were 650 at 4.0 ltrs. Just a thought.
Oh and if you did raise the limit get oil cooler, and keep your bearings cool.

[NinEFivEFourOH]

The 95s all had oil coolers on them, so I'm already good there.

I may look into raising the rev limiter on the car, depending on reliability and if there's any potential power gain from doing that.

[RCA1186]

hows this coming along?

[NinEFivEFourOH]

Slow, just need more money... lol. Next step is having the block worked on, then putting the motor all back together, build the new trans, then pull the whole old package out and do all the custom exhaust (true duals and headers).

[lanceslambos]

Dec 21, 2010 11:37:25 GMT -6 NinEFivEFourOH said:

id there's any potential power gain from doing that.

? that's pretty obvious, more explosions per minute = more power

[NinEFivEFourOH]

Not necessarilly, different engines have different powerbands; and it has a lot to do with gearing. You have to factor in where the power peaks in the RPM range and then take into consideration where each gear has the RPMs drop to with each shift, to try and keep each shift within the ideal power range.

[auroradude]

You may have been better off buying the brand new leftover Shelby aurora V8 that was on ebay. I just bought what i think was the last remaining engine from the plant, for $2000 on the button shipped. It's in my garage now, top to bottom brand new engine sealed in crate with shelby logo on the packaging

[NinEFivEFourOH]

My 4.6 engine will be built for less than that, sorry chap. AND worlds stronger.

[RCA1186]

The engine, trasmission, programming, exhaust and everything is going to come in under $2000?

[NinEFivEFourOH]

No the engine will be in that ball park. Trust me it will be very stout for what I have in it compared to a Shelby engine.

[Randy T.]

Any updates on the project?

[NinEFivEFourOH]

I'm in the midst of finished my Beretta GTZ up, after that I'll get back on the Aurora. I'm actually taking my 4t80e trans to Engineered Performance in Atlanta for Jeff to rebuild and put an LSD in for me (when I go to pick up the built manual trans and axles for my Beretta next week).

The next step in the build is the trans and then boring/building the block, then I can probably assemble the engine. After that it will be header and exhaust fabrication probably.

[NinEFivEFourOH]

I overcame a substantial obstacle with my build, that is, finding a good deal on 32 lifters... I ordered 48 for $6 a peice on ebay. (16 are for my Quad 4 build, which also uses the same lifters).

Here's the link if anyone needs some, they've gone up to $6.75 a piece, but that's still a great deal. They are US Seal brand.

www.ebay.com/itm/150685583053?item=150685583053&viewitem=&vxp=mtr

The next steps for the engine are to have the block bored and cleaned up, crank done, rods balanced, order all lower end bearings, new oil pan, and try to see if I can find some sort of ARP equivalent for main cap bolts... I thought I read on a Northstar forum somewhere that a rep at ARP said with the right specs on the bolts they could be made. How much? Who knows... But I want my engine to be as bullet proof as possible...

After this stuffs done, the engine can finally be assembled. Then it's just a matter of the trans build for the engine to be sitting in the car... After that, the fun part, header and exhaust fabrication! That's where this little guy comes into play...

www.summitracing.com/parts/EVT-1750BASIC/

[shelbyracing]

We don't actually have lifters. They are tappets, but I'd really love to find some lesser friction ones. Did you?

[NinEFivEFourOH]

I dunno they're just replacement lifters.