V8 Manta SCCA build
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Thread: V8 Manta SCCA build

  1. #1
    Join Date
    Sep 2011

    V8 Manta SCCA build

    Hi ladies and gents,
    My newest project is going to be to build my 75' Manta into a V8 SCCA racer. I got the idea from a few racer buddies of mine in town who run LS1s in their 280Z Datsuns. My goal is to run a carbed Small Block 350 with a 3 or 4 speed transmission(the Datsun boys used 6 speeds and said if they would've thought strictly about racing they would have used a lower gear count). I have a few questions about what the best options might be for a set up. Any info on what's been tried and works would be great. Here are the questions.
    1. Can the V8 and transmission be massaged into the stock subframe or would it be easier to substitute it with a GM subframe(i.e. Trans Am, Firebird etc). If I used the GM swap the 350 would drop right in, I would get better suspension components, disk breaks and power steering. My brother in law did a swap like that but it took quite a bit of time to get everything lined up just right and welded in.
    2. I'm planning on a IS swap in the rear. I've seen a build on here with a 3 series BMW but I'm not sure it would hold up to the V8. The Datsun boys run their standard IS with a built pumpkin. I wonder if that would be better suited than the BMW swap.
    3. To accommodate the adjustable suspension components front and rear that I have I was going to build some tubed strut towers and tie them into a cage inside the car. Are there any tried and true set ups or configurations for this?

    I know there are probably thousands of variables with all of the things I'm asking about, so I would like to thank each and everyone of you ahead of time for any and all information. I've been part of this forum for quite a few years now and have learned so much with the help of all of you.

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  3. #2
    Project 1450 supporter... Site Supporter My location RallyBob's Avatar
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    Mar 2002
    Spofford, NH
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    Bob Legere
    A SBC swap will make a Manta very nose heavy. It's already 54% front weight. Adding another 400-500 lbs up front (engine, cooling, suspension, subframe) will make it turn like a FWD car!

    Another thing to consider: to put the Camaro front clip in, you'd need to cut everything forward of the firewall off. The Opel's frame rails are part of the unibody. The width of the Camaro is much wider than the Manta. So while it would give you a-arms, steering and engine mounts, it would require very large fender flares to keep everything covered.

    My friend has a 355 Chevy in his 240z and it's pretty balanced, but the engine in a Z car sits a lot further back than in a Manta. You could do the same but it would require cutting and setting the firewall back about 15".

    I'm not sure what type of SCCA racing you're looking to do, but a V8 swapped Ooel doesn't fit into any actual club racing classes...are you talking about doing time trials/track days? If so you could probably swap in a smaller (lighter) forced induction engine and retain the Manta's suspension and maybe even improve the front/rear bias.

    One engine that is super light (about 100 lbs lighter than the Opel engine) and reasonable efficient (222 hp) is a Nissan VQ30. Just throwing ideas around.
    Last edited by RallyBob; 04-05-2016 at 10:08 AM.
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