Ok so I have decided on the 4.9 swap instead of the 3.5 that I already had. That being said I have read every article on here I could find under a 4.9 search. I have acquired a complete with fitting allante intake from Allante source in Florida. He is a great guy and had everything I wanted. I also just acquired my 4.9 engine complete with all brackets and harness/ECM. I have emailed back in forth with John a few times and got some really great advice. Awesome dude! I am going to buy his mounts, adjustable timing gear and possibly headers and valve train set up. I might just refresh the engine with rings and bearings and stab it to get it going and work the bugs out and then buy another one to build out the way I want. I don’t want to worry about breaking in a cam when I am messing with ecm, wiring and other conversion stuff if I don’t have to. So in doing research I can not find any thread where someone rebuilt a 4.9. John is a wealth of knowledge but I don’t want to abuse that source. I remember the 4.1s that were trouble if you pulled the heads. My goal is to bore the liners .40 over and use the N star pistons also raising the compression a point. Have read about difficulties actually measuring the sleeves height accurately thus making it important to keep sleeve arrangement in tact. I also remember a trick about torquing the head down partially with an old gasket to seat the liners and new o-rings first. Anyway I am really looking for tips and tricks to rebuilding the 4.9 successfully. This is for both a refresh and a total rebuild. Any good sources or information would be greatly appreciated. Thanks to all the 4.9 guys that have posted their build threads. I don’t want to reinvent the wheel. I know the 4.9 isn’t as popular as the 3.8 or the LS, but it’s a v8 that weighs close to original and bolts up to my getrag without a kit. When I build the motor I will do all the head work John recommends and also use a delta cam. They made me a really nice cam for my MGB. I drive the car daily now and plan to do so after the swap as well. I have other cars but I love driving the Fiero. Thanks in advance guys.

Paul

Paul

I am building my 4.9 as well. I am a little farther along but it is a slow process. If you are curious of what I have been doing here is my Facebook business page: Spade Customs.

Awesome I followed you and am Che king it out. Thanks all info is appreciated.

The 4.9L is a tricky engine to rebuild and there is a correct procedure to follow. It can be found here:
4.9L engine rebuilder articles

There are 19 pages of 4.9L engine rebuilding tips. We can thank Nathan Bittinger for bringing this site back online. Scroll down for the info.

Dennis,

Thank you I think.....lol. This is exactly what I was looking for, but now I am even a little more nervous. I just moved to VA and don’t have a relationship with a local machine shop that I trust so that is scary. The liners are what scare me the most. I use to own a shop back in the time of the 4.1 and we pretty much considered them junk when they blew a head gasket, which they all did. Was unaware that these guys existed. Their attention to detail is amazing. I can time sert the head bolt threads and will be detail oriented at measuring liner heights when I figure out how to measure them accurately. I wanted to bore the liners but now I may not if I can’t find someone with some experience doing it. At least I have a guide of what should be done so that is awesome, thanks again.
Paul

quote Originally posted by PAUL66: Dennis, Thank you I think.....lol. This is exactly what I was looking for, but now I am even a little more nervous. I just moved to VA and don’t have a relationship with a local machine shop that I trust so that is scary. The liners are what scare me the most. I use to own a shop back in the time of the 4.1 and we pretty much considered them junk when they blew a head gasket, which they all did. Was unaware that these guys existed. Their attention to detail is amazing. I can time sert the head bolt threads and will be detail oriented at measuring liner heights when I figure out how to measure them accurately. I wanted to bore the liners but now I may not if I can’t find someone with some experience doing it. At least I have a guide of what should be done so that is awesome, thanks again. Paul

The 4.9L has been successfully rebuilt by four forum members that I know of. Out of respect for their privacy I can't pass on their emails but the screen names are Johns 4.9 (that you know) V8Formula (Rick in MD) , PBJ (Pete in Canada) and Rockcrawl (Jon in PA) . At this point I believe that only the first two are still active in Fieros but if they read this post perhaps they will chime in.
There are certainly some shops that can bore the cylinder liners but if they are within spec you may just get away with honing them yourself. As for the cam: apparently the Delta grind works for power, but one guy that I know who included it in an all out build (also using N* pistons) ended up with rather poor gas mileage.

Dennis,

I have read many valuable post by all four of those members. I am sure John is probably the most experienced or at least has the most recency inside a 4.9. I feel guilty about asking to many questions of one person, especially when they have a business related to it. I will have to purchase some stuff from him so I feel better about it. 😁. I sure appreciate your input. I am really looking forward to building one. I am kind of OCD so I always sweat the details.

Paul

quote Originally posted by PAUL66: Awesome I followed you and am Che king it out. Thanks all info is appreciated.

Sounds good. Beyond what Dennis has pointed out Raydar and olejoedad are some resident 4.9 guys who can help you out as well.

quote Originally posted by Spadesluck: Sounds good. Beyond what Dennis has pointed out Raydar and olejoedad are some resident 4.9 guys who can help you out as well.

Raydar and olejoedad are the go to guys for some 4.9L performance mods. Radar did the Allante manifold swap while Joe changed ratios on his 4T60e and reported great results. PBJ did a turbocharged version of the engine and ran 12's and there was another guy who added a supercharger totaled his car in an accident but escaped injury. V8Formula/GT (Rick) and Rockcrawl (Jon) did all out 4.9L builds but apparently sold those cars. V8Formula is now busy on a 4.5L swap. There is some really good talent here on this forum.
As a side note years back Superchips developed a "performance" chip for the 4.9L but it has never been proven that it provided more horsepower. IIRC it just altered the timing curve.

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" 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
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[This message has been edited by Dennis LaGrua (edited 12-28-2020).]