Howdy folks, Darryl here again. This time, with an engine question.
I've been doing a lot of research on the 4.9L Cadillac. It's really starting to look like this is the engine for me. I however, did have a few questions, both about the engine, and the procedure to swap it into an 88 Formula.
- How much fab work is involved with getting a 4.9L to fit into the 88, and to get it bolted to the cradle?
- How much power are you guys actually getting out of the engine?
- What performance modifications are you doing to the 4.9L? Is it viable to get a set of headers on one of these with it squeezed into a Fiero?
- Has anyone had a custom machine shop build a set of Aluminum heads for this engine? If you actually did, what was the cost, how much weight savings was there compared to the iron heads, and how much power (if any) did you gain?
- Has anyone reliably hooked a turbo up to a 4.9L without turning the engine, or the TH440T4 into a grenade?
- What fuel mileage are you seeing from the 4.9L? City/Highway, Driving with grandma in the passenger seat/ showing off to the pretty neighbor girl?
- Has anyone ditched the factory fuel system for a Q-Jet, and has anyone ditched the factory fuel system for an EFI, like the Sniper, Fi-Tech, or MSD EFI? What were the results from each fuel delivery system, including factory?
- What advice can you give regarding the swap, be it tips on making it easier, making reliable power, parts to stay away from, etc?
Thanks in advance for your time folks, I do appreciate it!
P.S: Here's a picture of the car I'm planning on buying, so you guys can finally see what I'll be working with!
The engine is lightweight, cheap, compact and a relatively easy swap. If you want a lot of power, it is *NOT* the engine for you The heads are atrocious and will always be choking the engine from actually breathing.
A one-off custom set of billet aluminum heads (because that's how a shop could make just one set) would be a $10,000+ investment to pay for the design time and production.
PBJ turbo'd a 4.9 and ran it with a built transmission. That car drove well into the 12's, but was all launch with a low trap speed.
There was a user who made outrageous power claims regarding his builds which used a carb on the original TBI manifold... I don't think anyone who knew anything ever believed him.
Any ECU that can control a distributor Chevy can control the 4.9... The 4.9 is actually better in that regard than factory distributor Chevies, as it the cam synch for sequential injection in the distributor.
If you want a car that handles well, is fast stoplight to stoplight, turns heads by the sound alone, and is very practical in the Real World, then the 4.9 easily fills that bill. I like mine so much, I picked up a second, low-mile 4.9 and have it setting in the garage, so I can do a second build.
The engine puts out a lot of torque down low in the powerband, so launches are great, and passing on the highway is a matter of just pressing the foot...no downshift necessary. The sensation is just a great, low RPM shove against the back. For this next build, BTW, although I'm happy with the Caddy ECU, I will likely run a F.A.S.T. Multiport ECU....comes with a harness, too, and the whole shooting match costs no more than having a custom harness made.
The engine weighs just 10lbs more than the 2.8 it will replace.
Also, 4.9 engines are plentiful and inexpensive....but, of course, you'll prefer to find a low-mile unit. Nevertheless, plenty of high-mile 4.9s still run well. Reliable.
Ernie
------------------ '87 Fiero 4.9 5-speed
[This message has been edited by Warlordsix (edited 08-09-2020).]
John is also doing engine mounting brackets that, I believe, are a bolt-in to the cradle. (My installation was done, years ago, with fabricated brackets welded to the cradle.)
The Caddy 4T60E trans is a well documented swap into the Fiero. Just a couple of brackets are needed. Or you can do a manual. Pretty much bolts right up, with a few specialty pieces. (The manual gearing is way less than optimal, but it's still a complete blast to drive. The Caddy automatic doesn't do anything quickly.) I would recommend that you reinforce your cradle, where the front engine bracket and the front trans bracket are bolted. The 88 cradle is notorious for cracking and having mounts tear loose, on the front side.
You can gain a few HP (the general consensus is +20, but it's not really been proven back-to-back) by adding an Allante intake setup. But they're becoming as uncommon as chicken lips. John is also in the process of tuning a short runner intake bolted to an Allante base. We'll see how that works out.
With my manual trans, the best I'm getting is around 25 MPG, on the highway. Driving "around town" in mixed driving. I get ~19-20.
This is the regular Allante setup, bolted to a 4.9. Complete with "hot air" intake.
[This message has been edited by Raydar (edited 08-09-2020).]
My view on the 4.9L upgrade is that it provides the best torque for the cost. On a DIY install you can get it done for about $1500. The challenge is to find a relatively low mile engine. Its fast with the auto if you change the 4T60e sprocket and chain to give to a 3:33: FDR . ------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
[This message has been edited by Dennis LaGrua (edited 08-10-2020).]
I just emailed a company regarding a custom set of aluminum heads for a 4.9L Cadillac engine. Waiting to hear about pricing and their input on if they think a set of Aluminum heads would be of any real benefit in an application like this. I've heard from numerous people that the heads are incredibly restrictive, so maybe a custom set could really liven it up?
Also, there's obviously a weight savings to be had here, though how much is hard to tell. Those of you with a 4.9L, did you ever weigh the heads to see how much of the weight came from just them? I'd suspect we could shave, I don't know, 15 pounds off per head by going aluminum?
As Will mentioned, I'm probably looking at an astronomical price to have heads made. But, I plan on keeping the Fiero until I'm under the ground, so to me the money would be well spent, getting the car set up exactly how I want it. And who knows? Maybe a company having all the files needed to machine these heads would help other folks out in the long run, would cost a lot less to get a second set done considering all the AutoDESK files will already be done.
If the bore center is similar to an engine for which better performing heads are available, then swapping those heads on may work. The combo would still require a custom intake manifold.
Given the size of the engine, I'm not sure there's any other head that would come close to working.
I received an email back from that company I contacted. I wrote a very detailed email describing the project, and simply received a: "I Am Not Interested" from the company owner.
Does anyone else know a custom head Manufacturer other than Build and Tune?
If you're not ready to drop $10k on cylinder heads, don't waste their time asking for a quote.
The companies that do that go to the trouble of designing and building heads so that they can sell them into a market; even then, billet heads are $4-5k/set, so they don't design heads for a market that won't pay that price. There's no market to sell into for the 4.9, so no one is going to be interested.
I googled "billet cylinder head" and got at least a page of results.
You're much better off looking at the 4.9s bore center and head bolt pattern to see if there's something close enough to mangle into place.
[This message has been edited by Will (edited 08-12-2020).]
You can also ditch the distributor and run ls coils with an m90 supercharger. More torque than you need in a 4.9 and if you want to upgrade springs and port the heads some, you can have high hp power too. It’s only a tune and pulley change away. I use speeduino because it’s cheap, it works, and it well documented. Uses tuner studio like megasquirt but only costs $150 for an Ecu.
Will, I would honestly be willing to spend the money. Once I get this Fiero, I intend to keep it for life. Spending money on it to make it exactly how I want it isn't a big deal. May take me some time, but no big deal to me. I also collect firearms, and have spent $6000 on a single rifle, because it was something I wanted. Spending money isn't something I'm afraid to do.
Dear, do you have any idea as to what the power numbers look like out of your engine? How difficult is fitting the supercharger? I imagine the engine compartment is awfully cramped as it is with just an NA 4.9L crammed in there!
You can also ditch the distributor and run ls coils with an m90 supercharger. More torque than you need in a 4.9 and if you want to upgrade springs and port the heads some, you can have high hp power too. It’s only a tune and pulley change away. I use speeduino because it’s cheap, it works, and it well documented. Uses tuner studio like megasquirt but only costs $150 for an Ecu.
What you propose would require a ton of fabrication, metal work and tuning.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
[B]Originally posted by Reborn756:And have spent $6000 on a single rifle, because it was something I wanted. Spending money isn't something I'm afraid to do.
But the arms generally will be worth what you invest and more after you buy them (and if you want to sell them). The Fiero, generally, will not be worth 1/3rd to someone else of what you spend on them. I realize you said you don't plan on selling. But the surviving family learns this. And there are lots better car investments you can end up with instead of spending 10k on heads. Some of us have many of the valued arms you mentioned.
[This message has been edited by sourmash (edited 08-12-2020).]
Sourmash: In my case this rifle won't be. I have my initials engraved into it in Platinum. Rifle isn't worth a darn to anyone except me and eventually my family, unless I become rich and famous!
Dear: With those modifications, do you suspect the power is reliable? In the summer months I'll be driving this car a minimum of 40 miles a day, 5 days a week. Don't want it to blow up on the side of the road on my way into work!
Originally posted by Reborn756: With those modifications, do you suspect the power is reliable? In the summer months I'll be driving this car a minimum of 40 miles a day, 5 days a week. Don't want it to blow up on the side of the road on my way into work!
Well the more you deviate from stock parts, the less "proven to be reliable" your setup will be from the start.
From your idea to use one-off heads, that means you're seeking the thrill and challenge of new stuff, and the risk of blowing stuff up. For example, you may face head gasket problems... in which case you may have to do a second revision of your 10k heads.
Once you've debugged and resolved the issues that crop in road testing, there's no real reason (with sufficient resources) you can't have a reliable daily driver with a custom car.
But the best way to test reliability for daily driving is by daily driving it... so that's my approach. To reduce overall fuel expenditure, time, and wear and tear, I combine my testing/tuning with trips I'd have done anyway. I accept the risk of breakdowns/problems while commuting in order to get the setup working correctly. I'm never really in a rush to get anywhere though.
[This message has been edited by pmbrunelle (edited 08-12-2020).]
Brunelle: All fair points there. Given that the head would essentially be a copy of the OEM units I wouldn't expect any problems, but you're absolutely right: head gasket problems absolutely would be a concern, something I never factored in.
86Fiero: I've considered all three of the logical V8 options (Northstar, LS4, 4.9L). I'm not looking just for straight line performance. I want the car to handle well, and keeping it "trim" is going to be a big part of that. The LS4 is over 100 pounds heavier than the 4.9L, plus the transmission weight increase (if any). I'm of course open to any V8 options that meet my weight requirements. I'm specifically looking for a V8 so I have that V8 sound, which is why I'm not going the full 3800 cookie cutter route.
Well if you were just going to copy the OEM heads (same shape, but aluminium instead of cast iron), I don't think you would gain any power. Aluminium heads of the same shape would breathe just as poorly.
If anything, you would lose power due to sinking heat away from the combustion chamber into the coolant.
Seems like a bunch of headache for not necessarily much weight savings... OHV heads aren't generally so massive, though I haven't picked up 4.9 heads.
If you were going to go through the trouble of heads carved from billet, you might as well make them with different (i.e. sports car) ports, and intake manifolding to suit.
Intake and exhaust manifolds are likely to be manufacturable using more inexpensive cutting and welding of tubes to make weldments.
Nope, about two weeks of working on it on the side. I’m sorry if using a drill, grinder and welder are outside your level of expertise.
Here is the required adapter plate
While I envy your fabrication skills, trying to transform a low revving high torque engine into something it is not may not produce the results that you are seeking and if you achieve the power goal will reliability go along with it? The head sealing capability on the 4.9L is not great. That's why GM recommended adding sealer to the coolant even when new. If you evaluate the cost vs potential large power gain vs reliability, I do not believe that a satisfactory result can be achieved.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
"I imagine the engine compartment is awfully cramped as it is with just an NA 4.9L crammed in there!"
Negative. Plenty of room in the engine bay around the 4.9. Frankly, there's much more room around the 4.9 in a Fiero than there is around a 4.9 in a DeVille. Just relocate the battery up front like most folks do anyway for other good reasons.
This is not the best shot, but I can easily change all my plugs, replace the belt, alternator, water pump, AC compressor, starter, etc., without disassembling anything else first.
Warlord: That does fit VERY well in there. Man, almost looks like the car was built with that engine in mind, it looks that clean in there. Who knows, maybe if the Fiero would have lasted longer, the end result would have been one with a modified 4.9L, designed to better suit the application?
Warlord: That does fit VERY well in there. Man, almost looks like the car was built with that engine in mind, it looks that clean in there. Who knows, maybe if the Fiero would have lasted longer, the end result would have been one with a modified 4.9L, designed to better suit the application?
Zactly, Until I tell them, 99% of people who ask about this car have no idea that engine was swapped in. Even the exhaust fits perfectly in the stock location. Here's a photo of the muffler I'm using....deep, powerful rumble without the raspy sound you hear too often these days from guys who just make their Mustangs louder. My neighbors say my Fiero sounds like my other neighbor's Viper, and I have to agree. (BTW Can anyone tell me why photos just seem to post wherever the hell they want to post, before, after, in the middle of text?)
Warlord: That looks awesome. I'm a big fan of the Cherry Bomb Extreme welded mufflers myself. Think a set of custom headers and true duals would be possible, or is sticking with the dual out muffler a better idea?
Warlord: That looks awesome. I'm a big fan of the Cherry Bomb Extreme welded mufflers myself. Think a set of custom headers and true duals would be possible, or is sticking with the dual out muffler a better idea?
Most do the dual outlet for packaging reasons. 2.5" into the muffler and dual 2.25" out to the tips. Flow is not an issue. I think a true dual is possible (but likely tougher to route...I think getting adequate ground clearance beneath the driver's side, in particular, would be difficult). Nevertheless, I suspect some creative fabricators have made duals fit well enough.
I'll probably stick with the single muffler then, I had ground clearance issues with my 86 Trans Am due to fitting duals as well, wouldn't want that on the Fiero. Shame, I like true duals for the "diagnose which bank isn't firing right" capabilities, but I'd rather play it safe. I'm a stickler for quality!
Originally posted by Reborn756: The LS4 is over 100 pounds heavier than the 4.9L,
I don't think this is true of the long blocks. Engine weights are one of the hardest pieces of information out there on which to get apples-to-apples data. I've weighed a Northstar long block at 310 lbs.
But don't forget that when Gordon Murray was developing the McLaren F1, he put out RFPs to several manufacturers for the engine. BMW came back with "We missed your weight target by 20 kilos, but we brought 150 more HP than you asked for." I don't think there's anyone who would argue that a slightly lighter McLaren F1 with 150 fewer HP would have been nearly as famous as the F1 that McLaren actually built...
[This message has been edited by Will (edited 08-13-2020).]
Gordon is producing another greatest driver's V12 supercar now. If the LS engine DID come in at 100 lbs more, it's worth the extra power it can produce; the upside would be worth it. But it's not likely it's that much heavier.
And your personalized rifle has plenty of value left in it. It's not true that it's worth nothing to anyone else.
It is a Shiloh Sharps, and if you know anything about the wait times, you also know there's people that would do anything to get their hands on one.
The LS also requires a lot more to properly fit and hook it up, plus (if I read right) it requires a smaller water pump and some other compromises with the cooling system. The 4.9L fits well enough that those compromises don't need to be made (once again, if I read right).
The car is an original yellow 88 Formula with sunroof. Given the low build numbers of these cars, I'd like to keep from totally butchering it, just doing enough to make it a more spirited driver!
The LS4 is definitely a more involved swap than the 4.9, no doubt about that.
Keep in mind, the 4.9 is rated at 65 more HP than the 2.8, so it will definitely make the car more spirited. However, a 3900 V6 is an even easier swap and comes in 40 HP higher than the 4.9, although with ~50 ftlbs less torque. Technology has overtaken the aging platform. About 250 HP at the crank is about the highest I've ever heard of any built naturally aspirated 4.9 making.
If you're dead set on doing something as in-depth as building new heads for the 4.9, you probably should team up with John's 4.9 Performance mentioned earlier in the thread... I have no idea how big his customer base is, but he's quite fond of the engine. http://johns49performance.com/index.html
Also, Ed Parks of the Fiero Factory does (used to do?) in-house 4.9 swaps... not sure if he's interested in performance parts, though. https://thefierofactory.com/
I've been thinking for a while that considering how light and cheap the 4.9 engines are, it's a shame it's so hard to get power out of them, as they'd make good claimer engines
[This message has been edited by Will (edited 08-13-2020).]
Here's some good info on the 4.9, including several pages of step-by-step rebuilding instructions from the June 1994 Automotive Rebuilder magazine....all of this is posted to the old Fiero Addiction website. One thing to note is the specs listed for HP and torque. Both peak early in the powerband where we spend 99% of our time on the street. Bottom line, a 4.9 Fiero is definitely quick and fun on the street. Especially fun with a manual.
I figured you were talking about that sort of rifle or a Barrett .50 derivative.
My 4.5 is the slightly smaller version and is ok. It will keep up with today's traffic, particularly, it's quick off the line if you want. The previous owner had a 5 speed in it, and I believe two failed before he went with the auto. This auto trans performs "ok". And when cruising at interstate speeds it really will just keep increasing to where you're now driving too fast. But the gear ratio spacing isn't ideal. My 3.4 Chinese engine Equinox would probably outrun it.
Originally posted by Reborn756: The LS also requires a lot more to properly fit and hook it up, plus (if I read right) it requires a smaller water pump and some other compromises with the cooling system. The 4.9L fits well enough that those compromises don't need to be made (once again, if I read right).
What you are proposing to do to the 4.9l you are not really requiring any less.
As one who has done the 4.9l swap (performance cam, ported heads, ported intake, etc) - you are far better off going with the LS4 swap. The time an money I spend on my car didn't really make it a performer. The 4.9l is a quick and easy swap to get more performance than the stock engine, but my car would choke itself past ~4300 rpm. Out of the gate it was quick, but it was not a distance runner. A 3800SC Fiero would spank it's ass.
If you want a quick and easy swap with some decent gains, then go for it. If you want performance, look someplace else.
I wouldn't waste money on new heads/etc for the 4.9l or trying to built it into something it is not.
[This message has been edited by Mickey_Moose (edited 08-14-2020).]
