Hey all,

If I got your attention for the wrong reason, please don't start flaming. I've started this thread for anyone that wants to build a performance 4.x motor.

So the short story goes I did my 4.9 swap 8 years ago before the LS4 was an option/ only V8 available to easily fit my Citation X-11. A couple years ago I collapsed lifters on #1 and set in motion to do a full restoration and build my 4.9L. All the tricks later, I couldn’t get it tuned for anything and I really wanted to have a knock sensor option so I could tune without fear and possibly turbo later. The solution was using a 95 LT1 PCM, harness, TB, MAF and Knock Sensor. It seems everyone’s first instinct/ response is “That’ll never work or you’ll never get an Optispark to work”.

Here is what I have running now; a HEI/Optispark hybrid for sensor only paired with a coil per cylinder conversion (LTCC), a custom throttle body adapter, a LT1 TB, MAF & knock sensors.

[This message has been edited by 81 4.9L X-11 (edited 01-10-2012).]

Here's how the distributor went together.

Very nice, this is some awesome stuff. At least the Allante intake bends in the "right direction" with this FWD setup.

Thanx! I had to get the TB to turn up a little to clear the master cylinder, but it's all good & runs like a monkey.

To make this more Fiero related here is my 4.9 swap.


Needs some more paint and a good cleaning in the spring.

quote Originally posted by 81 4.9L X-11: Thanx! I had to get the TB to turn up a little to clear the master cylinder, but it's all good & runs like a monkey.

could you outline briefly all the mods to the motor that required such a drastic change to the intake and electronics?

Okay. Here's mine. You've got my attention.

------------------
Raydar
88 Formula IMSA Fastback. 4.9, NVG T550

Praise the Lowered!

Yea yea you Allante intake people think you are soooo cool don't you?

Only kidding. I would get my own, but I just don't think it's worth the time/effort, no money atm, and I personally don't like the look of it in the Fiero engine bay, it's so large all you really is that intake and not much of the engine on that side, plus all the cables and vacuum lines going to the intake on the opposite side of the firewall.

[This message has been edited by mattwa (edited 01-11-2012).]

Here's one dang pretty 4.9...



Racingman24's engine...

Wow, that IS a nice and shiny 4.9..I love the paint on the heads and block.. looks like candy apple red or similar.

That is a nice candy color! The one thing I would change on mine is I should have painted it on while I was doing the rebuild. Nice job - was the valve cover fade planned or run out of paint?

Very nice work, and a unique approach to solving your tuning problem.

Please keep us posted.

Joe

quote Originally posted by 81 4.9L X-11: That is a nice candy color! The one thing I would change on mine is I should have painted it on while I was doing the rebuild. Nice job - was the valve cover fade planned or run out of paint?

The valve cover was a planned fade. The engine isn't mine, but Racingman24's. The thing has P&P heads, Delta cam, and more but he has had problems with electrical stuff and gaskets and has gotten discouraged over the years so it hasn't moved much. It is a really great looking swap though. I believe he has the Allante' intake as well now.

Why would you do this? Were you just testing? LOL


Great build!

[This message has been edited by carbon (edited 01-11-2012).]

Wow, you had your own rocker plate made up!? Nice! Want to make anymore?

quote Originally posted by carbon: The valve cover was a planned fade. The engine isn't mine, but Racingman24's. The thing has P&P heads, Delta cam, and more but he has had problems with electrical stuff and gaskets and has gotten discouraged over the years so it hasn't moved much. It is a really great looking swap though. I believe he has the Allante' intake as well now. Why would you do this? Were you just testing? LOL Great build!

Thanx! That pic was from when I was setting the preload on the lifters, it was easiest to feeler gauge the lifters and see everything lined up. You'll have to let Racingman know there is another option now...

Cheers

quote Originally posted by 81 4.9L X-11: Yes, had custom ribs made to hold the roller rockers. My godfather (he's the Yoda of fabrication) did them for me after two local machine shops failed. I figured I'd see what kind of response the thread gets to see who was interested in them. The thing to know upfront is that they are not perfect bolt in. The pedastals for each rocker have to be adjusted with shims. It's not a big deal but worth it for valvetrain options. Cheers

Yea, considering all 4.9's had aluminum versions and can rip out if you rev it too high. The allante 4.5 had the steel ones but those are getting quite difficult to find. I would love to mod my 4.9 like that, I just feel it's not worth the effort. The Caddy ECM makes things worse.

Edit: And like I said, the Allante upper intake is awesome looking if it's the right direction. The lower intake coolant system, fuel rail, and no EGR is awesome though, one of my favorite parts. I understand Raydar and others have had tuning issues using a Allante intake and the Caddy ECM..another reason to go to a different ECM as well.

[This message has been edited by mattwa (edited 01-11-2012).]

Ya, I know building a 4.9 isn't for everyone. I'm hoping now the LT1 opens up the tuning arena & gets a few interesting builds. With the rocker ribs, the right springs and an inter cooled turbo - a 7k readline isn't out of the question.

What directions are you wanting the allante intake to face, towards pax side or just lean over the opposite side of the motor?

quote Originally posted by 81 4.9L X-11: Ya, I know building a 4.9 isn't for everyone. I'm hoping now the LT1 opens up the tuning arena & gets a few interesting builds. With the rocker ribs, the right springs and an inter cooled turbo - a 7k readline isn't out of the question. What directions are you wanting the allante intake to face, towards pax side or just lean over the opposite side of the motor?

It would be really nice If I could just turn the Allante intake around 180 degrees, so it looks like yours in a FWD car when viewing the 4.9 in the engine bay of a Fiero. I'm not sure if doing that will create more problems then it's worth. I know you would have to modify the lower intake and/or runners to make it work, and I'm pretty sure if you got that far the Throttle Body would be right where the Passenger decklid hinge is. Then there is the problem of getting the throttle cable to work with it in that location. I would consider doing an Allante intake upgrade one day If I was able to flip it around like this.

Anything can be done with time and money, but is it worth it? Subjective question. IMO even with the increased HP, flow, and looks of the Allante Intake, you are still stuck with squashed heads with tiny ports.

If I or someone found aftermarket or at least better flowing heads, I'd be very very interested for the future. Then I could possibly make or modify a better flowing intake to it and use the Allante top runners.

EDIT: Actually, how much bigger did you make the exhaust ports after the P&P? They just look so small to me.

[This message has been edited by mattwa (edited 01-11-2012).]

quote Originally posted by mattwa: It would be really nice If I could just turn the Allante intake around 180 degrees, so it looks like yours in a FWD car when viewing the 4.9 in the engine bay of a Fiero. I'm not sure if doing that will create more problems then it's worth. I know you would have to modify the lower intake and/or runners to make it work, and I'm pretty sure if you got that far the Throttle Body would be right where the Passenger decklid hinge is. Then there is the problem of getting the throttle cable to work with it in that location. I would consider doing an Allante intake upgrade one day If I was able to flip it around like this. Anything can be done with time and money, but is it worth it? Subjective question. IMO even with the increased HP, flow, and looks of the Allante Intake, you are still stuck with squashed heads with tiny ports. If I or someone found aftermarket or at least better flowing heads, I'd be very very interested for the future. Then I could possibly make or modify a better flowing intake to it and use the Allante top runners. EDIT: Actually, how much bigger did you make the exhaust ports after the P&P? They just look so small to me.

everybody complains about the tiny ports of the 4.9L... if you look at Robert's pics, you will see that there is quite a large amount of material that can be removed from the ports to help them flow better. combined with the larger intake valves, i think the headwork is the biggest part of his build that will really wake up this motor. I've personally been in his car as he pulled hard past 6500 rpm in 1st and 2nd gears..There is no more short breath issue in the upper rpm band after the work he did.

quote Originally posted by stickpony: everybody complains about the tiny ports of the 4.9L... if you look at Robert's pics, you will see that there is quite a large amount of material that can be removed from the ports to help them flow better. combined with the larger intake valves, i think the headwork is the biggest part of his build that will really wake up this motor. I've personally been in his car as he pulled hard past 6500 rpm in 1st and 2nd gears..There is no more short breath issue in the upper rpm band after the work he did.

Alright then, sounds good enough to me. Where did the larger intake valves come from?

The intake valves are a standard SBC size - I'd have to look up the exact size, but any competent shop doing head work should know sizes with out problems. I opted for the stainless valves and the only adjustment needed was the valve stem hieght, but again any decent shop should handle that.

I understand what yours saying about the Allante intake layout, but honestly - who's looking at the motor when it's planting you back in the seat?

Cheers

In response to the custom rocker setup, that looks great. Now, what about using self aligning roller rockers? Would drilling and taping an aluminum rocker bridge for the new rocker stud help with the premature withdrawal issue? Maybe if the stud is long enough to place a nut on the backside to spread the load out. I would imagine with this setup there is the advantage of an adjustable roller rocker setup without the major modifications. Or am I barking up the wrong tree?

quote Originally posted by stickpony: everybody complains about the tiny ports of the 4.9L... if you look at Robert's pics, you will see that there is quite a large amount of material that can be removed from the ports to help them flow better. combined with the larger intake valves, i think the headwork is the biggest part of his build that will really wake up this motor. I've personally been in his car as he pulled hard past 6500 rpm in 1st and 2nd gears..There is no more short breath issue in the upper rpm band after the work he did.

The intake ports are a bigger hrudle to over come.

look at the pushrod in this picture and what lies behind them.

that is a BIG intrusion into optimal flow.

I just googled that intake... I have never actually paid attention before... the inside 4 intake runners are seriously just pinched off to clear the pushrods? Wow...

[This message has been edited by carbon (edited 01-13-2012).]

quote Originally posted by FieroWannaBe: The intake ports are a bigger hrudle to over come. look at the pushrod in this picture and what lies behind them. that is a BIG intrusion into optimal flow.

the picture is very deceptive looking only at the rear banks.. look at the bottom half of the picture, the front banks. You will see how much space is actually between the pushrod and the entrance to those two center intake ports. Additonally, if you have seen the bottom side of an allante lower intake manifold, you would see that the intake runners wrap around the pushrod quite effectively without disturbing the flow at all. this is yet another good reason why the Allante intake adds a real world 20HP over the stock 4.9L intake

quote Originally posted by 81 4.9L X-11: I understand what yours saying about the Allante intake layout, but honestly - who's looking at the motor when it's planting you back in the seat? Cheers

I have issues knowing there is an engine in my Fiero that I built that I think is ugly. I'll know it's there, and that's enough to make me not do it.

But at this point, I don't think it's worth doing the Allante intake, since almost everything custom has to be remade, and I just want to leave it as is with some minor tweaks for a cleaner look. My Fiero has been down for far too long and I just want reliability for a change. #1 on my list is I have always HATED the 4.9 thermostat housing and way it routes both coolant feed lines. And it's leaking again.

quote Originally posted by chetw77cruiser: In response to the custom rocker setup, that looks great. Now, what about using self aligning roller rockers? Would drilling and taping an aluminum rocker bridge for the new rocker stud help with the premature withdrawal issue? Maybe if the stud is long enough to place a nut on the backside to spread the load out. I would imagine with this setup there is the advantage of an adjustable roller rocker setup without the major modifications. Or am I barking up the wrong tree?

I personally would never use Aluminum for those types of forces for any larger cam with higher RPM..or just higher RPM period.

quote Originally posted by FieroWannaBe: The intake ports are a bigger hrudle to over come. look at the pushrod in this picture and what lies behind them. that is a BIG intrusion into optimal flow.

You know, this never dawned on me either, I never noticed that...wow. +1 for the Allante intake if it's better in that area as well.

[This message has been edited by mattwa (edited 01-13-2012).]

What is your opinion about self aligning rockers?

quote Originally posted by chetw77cruiser: ...an aluminum rocker bridge for the new rocker stud help with the premature withdrawal issue?...

The Allante rocker supports are made of steel, unlike the 4.9s which are made out of thicker, but weaker, aluminum.
Which is exactly why the Allante pieces are recommended for higher RPM use.
I have heard of several aluminum 4.9 supports failing, due to the studs pulling out. I have never heard of an Allante rocker support failing.


Edit -

quote Originally posted by mattwa: ...I understand Raydar and others have had tuning issues using a Allante intake and the Caddy ECM..another reason to go to a different ECM as well.

My tuning issues were more a product of my own imagination, than anything.
See my thread about Allante tuning and "ping".

With a few minor tweaks, I'll be able to live with it for now. It should be fine for what I've got.
Of course, there are limitations. If I go nuts with the hardware, I may run out of adjustment in the Caddy PCM.
I have a 7730 on the shelf, but the other options are looking more attractive, too.

[This message has been edited by Raydar (edited 01-14-2012).]

I've not dealt with self aligning rockers, but I know they've been used for plenty of performance motors. I'd stay away from the stock aluminum rocker rib, the manual say they're single use items - torque once and done. You might have a more affordable option there if you can get some allante ribs.

Mattwa - I wasn't trying to sway you on your build, do it how it will make you happy. When I get caught with a similar scenario, I prefer performance is all. There are a few things I'd like to look different on mine, but I'm happy with it overall.

Luckily I already have a complete allante engine to build up or use parts from. Thinking of a way for others who are not so fortunate to be able to make things work better. Oh well.

[This message has been edited by chetw77cruiser (edited 01-13-2012).]

quote Originally posted by chetw77cruiser: Luckily I already have a complete allante engine to build up or use parts from. Thinking of a way for others who are not so fortunate to be able to make things work better. Oh well.

What kind of build are you looking to do? Any chance you have one of the special Allante valvetrains?

Unfortunately I do not have the special valve train.

What I am looking at is building up the 4.5 to be a rev friendly engine. With the shorter stroke and a longer rod package from a 90 4.5, I figured that the engine would be able to get a few more RPM with the flow of the heads. I am not looking for gobs of torque or 9000 RPM, but something that better matches the manual trans. I have a place that will either weld up the stock cam and grind it to any specs I want, or cut a brand new cam for a few bucks more. With the cam service, I can have a cam made with the same base circle but with any lift and duration. So technically I would not need adjustable lifters. I am also going to either have the crank neutrally balanced or match balance the flywheel to match the stock flex plate. The other option is to use a 4t65e with aftermarket control. There are many more things that I want to do, but I will save that for another thread.

quote Originally posted by chetw77cruiser: The other option is to use a 4t65e with aftermarket control. There are many more things that I want to do, but I will save that for another thread.

See if an LS1 computer will control a 4T65E... There are aftermarket 24x reluctor wheels on the market; you could use the LS1 computer and coil per cylinder.

Anyone want to donate a LS1 computer and harness to the cause? I already have a computer that allows C.N.P ignition and a whole lot more, but I am willing to try something different. I have a friend machining a oil pump drive with a sensor to identify cyl #1 to replace the distributor. Hopefully he will have it done soon so I can post a photo of it. Maybe it will be compatible with the LS1 PCM, I will have to do a little research on that one.

The trans controller I would use with the 4t65e is the Microsquirt with the Megashift code. The controller is weather tight(after I am done with it) and even allows the use of tap/paddle shifting if wanted.

We should start a new thread so we don't hijack this one.

[This message has been edited by chetw77cruiser (edited 01-13-2012).]

quote Originally posted by Will: See if an LS1 computer will control a 4T65E... There are aftermarket 24x reluctor wheels on the market; you could use the LS1 computer and coil per cylinder.

i wonder if the cam sensor in the caddi distributor will work with the ls1 pcm without modification??

Good Question. I will get back with you on that.