The SD4 is a 80's design that never went into mass production. It is capable of making excellent power but keeping it streetable is a challenge. I believe that engine has run its course but they occasionally come up for sale. Jennifer Goss the president of MAFOA owns one and may be able to provide some leads.
------------------ " 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 was able to get ahold of a couple of blocks and heads. basically a nearly complete engine without intake and exhaust along with a marine crank supposedly. I'll have to run the part numbers to know for sure.
If anyone has some intakes like the 4 barrel or two barrel let me know.
Thank you IMSA GT. I do appreciate the response. I've got some Weber-style manifolds, id just need to get the actual carbs however I think I'd rather go the route of EFI but if need be ill find some Webers.
I was able to get ahold of a couple of blocks and heads. basically a nearly complete engine without intake and exhaust along with a marine crank supposedly. I'll have to run the part numbers to know for sure.
If anyone has some intakes like the 4 barrel or two barrel let me know.
I would check the Marine crankshaft. The flange at the back may or may not fit the Fiero flywheel. I would assume some used SD4 parts are around because the engine is largely obsolete. I've read about a Pontiac drag race car by Nunzie Romano) that ran in the 12's so it is powerful . That video is on You Tube. here it is 12 second SD4 run
[This message has been edited by Dennis LaGrua (edited 08-09-2023).]
Thank you IMSA GT. I do appreciate the response. I've got some Weber-style manifolds, id just need to get the actual carbs however I think I'd rather go the route of EFI but if need be ill find some Webers.
Kinsler still manufactures the manifold and EFI for the SD4 if I'm not mistaken. I have no idea about the cost.
[This message has been edited by IMSA GT (edited 08-09-2023).]
The last time i contacted Kinsler they have discontinued their SD4 intakes. Jessel will make a set of shaft rockers though.
I do have a SD4 cylinder head and intake on Ebay. SD4 specific Parts are hard to come by, but there are capabilities to use Factory parts. Very early duke crossflow heads can handle substantial porting and people have pushed S10 blocks to much higher power levels using marine crankshafts with extra machine work. Metal timing gears are available. Used cams pop up once in a while, but cores for new grinds seem to he limited to flat tappet cams at the moment. Bullet Cams may have billet cores to use for a roller. I would think with lots of careful parts selection. And looking for the right parts from the right application, a 150hp duke could be built with reworked factory parts from other applications. There is a video of just this on youtube. Just no parts as used on the fiero. And the intake is probably hardest hurdle to over come.
[This message has been edited by FieroWannaBe (edited 08-29-2023).]
So I decided to build a MPFI system with 2-bbl throttle body (from V8 Dodge Durango) on an Edelbrock 2-bbl carb manifold. Works great now (30 mpg on the highway too!) https://www.fiero.nl/forum/...L/000077-6.html#p226
Thanks y'all for the helpful responses. I do appreciate it. Sorry its taken me a bit to respond.
Dennis. - So I have two cranks, a Marine and a Callies. The Callies was from the "complete" motor and I don't think they'll be a problem with it. It has bolt holes all way around the face of the crank. The pattern on the Marine seems to be proprietary kinda like you was talking about. I'm not opposed to having it or a flywheel modified to fit.
IMSA. - I know of a couple of places i can get the Kinsler intake. I've thought about it. And may still decide later on.
Wannabe. - I know about your 2 barrel intake, I was the one who made the offer of $150 plus the shipping. My offer still stands However, last I checked it's gotten past 3 bills so I don't think that's a good proposition anymore. The reason I was looking for one is because of the issue Fierosound was having out of the fitment for the Fiero.
FieroSound. -I'll defintly check out Shane Clogg and the performance Duke Community group on FB thanks for the lead.
The plan is to build two motors. The first and more important one for my Fiero, cause thats what all the cool kids do. The second one for my 1st gen s10 which will have the guts out of a olds bervada. AWD with a potient 4banger kinda like a scyclone.
.JPG)
However, last I checked it's gotten past 3 bills so I don't think that's a good proposition anymore. 
