Hi guys, I currently have a 383 hsr etec 200 headed sbc with a t56 in my 89 Iroc. I hated the driveability of my maf tpi setup so i went in search of an alternate ecm and found Mike at eficonection and he built me an obdII harness based off the 01 02 express van that uses the ls1 style computer and a first gen style motor. Anyway, I got the system working and it does everything I was hopeing for. Except that I have recently come down with big-block-itis. As far as I can tell running a mark V or VI should be possible since it has the crank reluctor wheel, sensor, and other electronics to comunicate with the ecu. I also can run the 4l80e tranny and have control over it with my present harness. My problem is that few aftermarket products are avalible for the mark v and vi such as in the oil pan department. So i was wondering if any of you know if the stock pan for one piece cranks will fit or if there is an alternative. Just so you know my plan is to run a 1 peice 4.25 stroke crank, i beam 4340 rods, a decent forged piston, mild alluminum heads, hyd roller cam, 1.7 roller rockers, and the edelbrock efi intake with an elbow and a 90 ls style t.b. Plus i'll take advantage of the bbc's stout bottom end with a little nitrous. Say a 250 shot or so. All of this under the stock hood and with a moderate exaust note so i don't scare away all the localls that are used to my little small block. My car was painted recently and looks like a really clean, stock (i hate that word)black iroc so i don't want to have a big hood or long tubes draggin over speed bumps. What do you guys think?

 

Are you certain it will fit under the stock hood, or is this an assumption?

 

There is a local guy around here that builds alluminum elbow for the forced inducion ls1 crowd and these are just under 3" tall. His elbow out preformed the edlebrock one of simular size. The intake is a single plane design that isn't too radical. I personally have seen a bbc with a dual plane intake and a low rise air cleaner in a thirdgen but to answer your question, no i do not know it will fit. If I absolutely had too i would get the turbo hood that is aroung a 2" cowl that still has the hood luvers and just fiberglass in the holes it has. But I really think I can make it fit.

 

GEN V block is junk. Luckily GM only produced it for about 5 years before switching over to the Mark VI block.

Gen V - Production started in 1991
Start of the one piece rear main seal
Steel crank but I think all the BBC engines after 1991 have steel cranks.
No place to mount a mechanical fuel pump
Peanut port heads and to use any other head, proper head gaskets are required or coolant will leak into the crankcase.

Mark VI
Much better casting
Can use older Mark IV casting heads
Can mount a mechanical fuel pump
Cast aluminum timing chain cover
Has a lot more sensors such as crank position etc for the ECM

 

Thanks stephen thats exactly what i needed to know

 

I found a mark 6 core with everything from the f.i. intake to the oil pan. It has the passenger side serp stuff as well. All of it for 600. Is it a fair deal? I also bought a 4l80 pull out for 400. Guaranteed to be in perfect working order. What do you think?

 

That transmission is pretty big. I don't know if it will fit in your car. Might do a search on this site to see what people have experienced.

 

Big and heavy. The 4L80E is around 250 pounds. It can be installed into a third gen but it's not a direct swap. Considering a third gen weighs a lot less than the lightest pickup truck the 4L80E was offered in (91-93 454SS), you really don't need a big heavy transmission in the car.

If you need a strong transmission that can handle lots of power and have an overdrive, the 200-4R is a better choice and an easier swap. If you don't need the OD, there are other options.

 

Around here there are a lot of fourth gen ls1 turbo cars, alot as in 5 or 6, and they have had really good luck with the 4l80. The guy a the local speed shop that built these cars says he'll never go back to a 4l60. I know they're heavy and the mount is about 8 inches further back. I just hated my 4 700r4's i went threw, and my t56s' gears are SOOOO close that i dont think a 496 would like having a 1000 rpm power band. The bbc would want longer pulls between gears. I dont know anything about the 200r4. I'll research it a little. Thanks.