McLaren replica build base on a Manta

Russ Noble

GT40s Supporter
Lifetime Supporter
Re: Headers finally tacked up

I'll never do this design again (onless I can put the collectors up and over the transaxle). Just too much time and work for what...3 or 4 HP?

Ah but Terry, its the sound! It'll be worth all the extra work!

But just to cheer you up, how authentic is it? Did Mclarens ever have crossover exh? ;)
 
Re: Headers finally tacked up

Ah but Terry, its the sound! It'll be worth all the extra work!

But just to cheer you up, how authentic is it? Did Mclarens ever have crossover exh? ;)

Not that Im aware of, but I dont want to disillusion Terry after all his hard work...:)
 

Terry Oxandale

Skinny Man
Thanks Russ...just twist that knife a bit before you pull it out. :shout: :D

Yep, that was an annoying thought all through the fabrication stage. The one thing that allowed me to dismiss it was the fact that the M8 for the most part had the exhaust primaries exit down and then out the back low and under the panel, which was impossible with the framing I built (couldn't and didn't want to hang the motor off the firewall). So either way, the exhaust is not going to be very accurate.
 
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I have to addmit Terry, that is a really nice system and I have been battling the "Authentic Detail Demons" when it comes to things Like exhaust and other little things that when you are building a "Replica" are important. But my View is, unless you are building a "Nuts & Bolts Replica" that you want people to have a hard time telling apart from the "Real McCoy" Its personal wants that are important, That being said Russ And Jac Mac are right about McLaren never doing the cross over, Although those Big Blocks still sound great , there is nothing and I mean NOTHING that sounds like a GT40. Is that down to the cross over or is it more to do with it being a Ford engine. What I'm really asking is will the Chevy sound the same.
Cheers Leonmac.
 
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Russ Noble

GT40s Supporter
Lifetime Supporter
What I'm really asking is will the Chevy sound the same

Leon,
I remember Neil Doyle's F5000 Begg FM2 had a crossover on a chevvie motor so if you can remember what that sounded like you will know! Too long ago for me, I can't even remember what the weather was like yesterday.
 

Kevin Box

Supporter
Guys

A few guys tried crossovers on jetboats and I think it is the crossover that does it.
If my memory serves me correctly there was a Hemi and a BBC with the crossover in early 90s

They sounded bloody incredible.

KB
 
Thats done it for me, I'm doing a cross over exhaust. BTW Russ, contry to what I told you about buying a complete Engine Ex US, I have started geting bits together and will have a complete 509" engine shortly I already have the short block and have a complete top end sussed (Just need to tell the wife) and see if she will let me spend the $$$, sorry to Hijack your thread Terry.
Cheers Leonmac
 
Terry,

I really enjoyed watching your YouTube videos of the Mclaren build, thanks for posting them.
Your 180 degree headers look fantastic, and I can tell you the sound will be one of your favorite things about driving your car

Jack
 

Terry Oxandale

Skinny Man
Dang, 500 + CID :stunned:


Thanks for all the notes and comments everyone. I’ve finally come to terms on the compromises between structure, appearance, fabrication experience, and finances on this build. I will feel very fortunate and blessed if the package drives and looks good regardless of its accuracy. It would just be nice to make it all as correct as possible, but doing that may prevent the eventual pleasure of driving it at an age in which I can enjoy it.

I'm hoping the sound and the uniqueness of the exhaust will make this worthwhile. I'm curious of what affect the eight intake stacks will have in regards to sound as well (being they will be right behind my ears without any barrier.

So…I’m sweltering in the heat and humidity of Arkansas as I finish the last bit of work on the headers. Then leave town for two days, come back home, and the headers are nearly a solid brown. RUST! Seems everything ferrous I came to grips with during the last week has a layer of corrosion on them from sweaty hands. I’ve since Scotchbrited them with oil to keep the rusting down until they get their ceramic coating.

Any of you guys ever use the “other” header coating colors available, such as black, or titanium? I've always used the silver finishes in the past, but wondered about another color this time around.

Ox
 
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Go with the silver, I have seen both white and Black headers and they don't have the visual efect that the shiney silver ceramic finish has. One thing and it may have been a poor quality job, I had a set done a few years back on my chevy pickup and they went dull after a few months use, they still looked OK but didn't keep the shine they had, is this normal with the ceramic coating.
Cheers Leonmac.
 
Fantastic

Have not seen too many Mantas and the ones I have were sort-of cheaply done or drag racey-ish.

Ox my man....you will have a stunner when done, you really are kicking (some) of our butts!

Mine included.

Your posts are one of my favorite, I look forward to each one.
 
I have always been patial to white headers....CLEAN white headers. If the ceramic allows one to keep them clean then I'd say go white. Otherwise silver it should be, black will just hide your handywork, and THAT would be a crime.

I should be able to get back on my car in the next week or so after some extended time away. Thanks for the inspiration.
 

Terry Oxandale

Skinny Man
It seems that the project has progressed slowly lately, but it’s only because I’ve finally started detailing the systems that I “roughed in”. The ITB set-up was dismantled, the throttle shafts modified, bore ridge removed to make a smooth 60mm to 48mm taper, and the throttle linkage completed with stops, springs, and cable.

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The fuel system is finally completed with pump, filters, one-way valves, and regulator, but still need to fabricate some fuel rail clips to keep them from lifting. The battery box was welded up and attached to the base of the passenger side pod. So with the battery, pump, two filters, and the water pump, this pod is pretty much filled up. So much for some planned storage space on that side. Still have the full storage space available on the driver’s side though. The plan here is to install a sufficiently strong lid on the battery box to help support the panel cover as a “step” used to ingress and egress.

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Lastly, the headers are welded up sans the O2 sensors and collector tabs.The grandiose 180º headers I previously constructed had to be put on the shelf, and newer shorter-tubed 4-into-1 headers fabricated due to the excess space the other headers took from the VERY limited room I'll have under the bodywork. The newer more compact headers provide more than enough room between headers (over the bellhousing) to mount a remote coolant reservoir and over-pressure cap.

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I’m just about ready to call it quits with this daily 98º weather and 75% humidity. Between the heat and mosquitoes, I’m looking forward to September REAL bad,
 
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I have to say, what a shame to see the 180s gone. they were looking so good. Your ITB system is looking really good and the progress you are making is fantastic. I have been working on mine and hope to have some photos to post soon. I always look forward to your posts, keep up the good work.
Cheers leonmac.
 

Darnel A.

Supporter
That's it! You have found the Holy Grail of the GT40 Scratchbuild - cheap ITB's! Please go into more detail (what year LHS, how are the shafts connected, what mods to the shaft you did, what size injectors, were did you get the rails, etc.) I will be at the Pick- n- Pay next Saturady scoring me some Throttlebodies! I was thinking of using motorcycle TB's but these fit the bill to the Tee!

Great Build!



Darnel
 

Randy V

Moderator-Admin
Staff member
Admin
Lifetime Supporter
That's it! You have found the Holy Grail of the GT40 Scratchbuild - cheap ITB's! Please go into more detail (what year LHS, how are the shafts connected, what mods to the shaft you did, what size injectors, were did you get the rails, etc.) I will be at the Pick- n- Pay next Saturady scoring me some Throttlebodies! I was thinking of using motorcycle TB's but these fit the bill to the Tee!

Great Build!



Darnel

Check this thread out..

http://www.gt40s.com/forum/gt40-tech-engines-induction-exhaust/30864-lsx-weber-intake-manifold.html
 
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