evilstuie

Hi Guys,

I've got a 400SBC, XE270HR cam, AFR 195s ported to about 210-220cc, HSR motor with 2.77 gears and stock converter on a 4l60e running 0411 PCM, and had a headache with the headers.
4 sets I've tried, nothing fits, and because the afr's are angled plug, my old headers wouldn't fit either.

My question is, how much power will I lose bolting on a set of stock exhaust manifolds, as opposed to the extractors/headers?

And...
Regarding the stock manfiolds, is it worth and are you able to open them up by removing some of the excess from the inner diameter of them for better flow?

Lastly, how much better would it be to use the headers I have and pipe the fouling pipe directly across to the next pipe, so the join is an inch or so from the port, just for 1/3 and 2/4 pipes?

Dyno Don

iTrader: (7)

Stock manifolds would choke that motor to death.

You need these, they fit and work with AFR angle plug heads.

evilstuie

Sorry...
Forgot to mention the most important part...
Its a right hand drive conversion and I'm in Australia.





Clearance issues.

evilstuie

I think I tried those as well anyway



Still over an inch off on the mounting bolt before it hits the steering shaft

roadthrills

You're over complicating this. Typical hot rod fab stuff. D shafts, u joints, and a support bearing. http://www.bing.com/images/search?q=...ng&FORM=HDRSC2

evilstuie

Not quite sure what you mean by that?
Do you mean modify the steering system to suit the headers?

The steering is already in place, it was professionally converted to right hand drive doing a mirror conversion using a GM RHD steering box.

The problem is the headers wont fit because the steering shaft is in the way, because the motor is offset, there's less room on a RHD car.

Orr89RocZ

iTrader: (20)

May need to fab a custom set for that motor. Manifolds would kill it. Block hugger types wouldnt do much better and could hurt plug access still.

evilstuie

By kill it do you mean power loss or actual harm o the motor?

I'm going to try and beat the **** out of the ceramic coated ones and see if I can heat them and shut n cut to get them in, already bought the heat wrap to hide my shame when I'm done

LX_SS

Clearance on that sucks, Have you tried removing the steering shaft and seeing what the headers sit like ?

Maybe it wouldn't be too bad to do a support for the steering shaft to run over the top and then down in front of the header with a universal or double uni.

evilstuie

Yep, really sucks.
If the steering column wasn't there, it'd clear fine, they f-body headers.

What you've said would possibly work, I just wasn't sure about modifying the steering shaft, safety wise, or modification plate/engineering cert wise.
I mean it has a RHD mod plate, so I could always say that's how it was when they converted it, but still.

LX_SS

You can do whatever you want on the steering shaft, it just can't be welded from 2 pieces without x-rays and in your particular case, it must be telescopic as your steering column is not.

Orr89RocZ

iTrader: (20)

Mean performance wise it will suck. Unless you have a turbo on the end of the manifold

evilstuie

So....
In theory does mean I can do this?



Green is current steering shaft.
Orange, steering box
Red new shaft pieces
Purple unit joints, braced against body/chassis.

LX_SS

yup, provided it moves freely and doesn't bind

evilstuie

meh, just looked at some more photos and it won't work.
The headers are hitting on the shaft only inches from the steering box input, so even changing the angle 38 degrees will still only give me a 1/2" extra room.

The only other way to do it would be to (and I'm pretty sure it's impossible, mount the box so the input is on an angle and pass it through the chassis and back up to run alongside the edge of the engine bay, then angle back to the steering wheel.

I'm actually considering how didficult it would be to change from a mirror conversion to a chain conversion and run a LHD box with steering on RHS....?

Night rider327

iTrader: (13)

In post #3, pic #1... Is the header lined up and bolted to the head?

If so, all you need to do is dimple the header tubes in 3 spots.

Mark header where it is rubbing. Take it off, lay a round 3/4" bar, rod, old socket, etc on header tube and hit that rod with a big hammer, until you make a nice rounded indent in the tube.

evilstuie

Yes, its attached properly to the header, but post #4 pic #2 that's where the mount is, so it still needs to move over another inch and a half before the motor will install.

Night rider327

iTrader: (13)

Oh ok, somehow I missed that mount bolt hole misalignment.

TTOP350

iTrader: (8)

Modify the 1st tube and be done with it. I hightly doubt you'll find a drop in set.

evilstuie

That's my hope, but everytime I talk to any exhaust shop about modifying headers, they start to put on the "it's such a hard and expensive job" voice as I hear them rubbing their hands together in the background.

I think if I cut the front pipe about 10mm before the flange, remove about an inch or so of the pipe, then heat the inside of the bend and push the pipe back towards the flange, and then get it welded it should clear the plugs, sound right?

Also, just to assist with it, I found a drop in replacement Jeep Cherokee steering shaft for $60 i ordered, so that should turn up next week and then I can get a bit more room and rid of some steering play at the same time.

LX_SS

Think you will find your play will still be there, as its more likely the steering box not the shafts.

Fingers crossed it works for you, but i have some doubts with the universal fitting the steering box itself especially if its a hq-hz unit. The hq-hz units dont have a full spline, only about 1/3 the shaft is splined.

mmadden55

Can you weld? I would suggest getting a header build kit and building a mirror copy of your headers or something custom that will clear.

http://www.summitracing.com/parts/sc...FZOBaQod0nwORQ

Camaro86IrocZ

iTrader: (1)

Don't worry 'bout bashing em in, No power loss..

https://www.thirdgen.org/forums/exha...ader-bash.html

evilstuie

Well some good news / progress...

the headers fit!!!
I just have to limit myself to forwards only!


When the new shaft does turn up though, it looks like I might be able to bash the headers into submission

Of course now I've gotta figure out how to get the header to the cats on the other side of the chassis....?

peterc005

Which headers are they and how did you get them to fit?

Be interested to see if the Jeep steering shaft fits a RHD car.

evilstuie

Hey Peter,

Clipster is the name/style, just got them on ebay $250 for a set of ceramic coated ones.

Jeep shaft is direct fit, no mods needed, its a telescopic shaft so you just heat it up to loosen the glue and adjust to length.

I did nothing to them so far, but will need to either bash them in a bit on #1 exhaust pipe, or cut it a bit and pull it in towards the motor.
Not sure where to go with the pipes from the transmission onwards though.

MoJoe

iTrader: (5)

Is there a reason you can't use the factory routing? These are DynoDon dual cat version. Or, you can use a single cat version.

evilstuie

I've got dual 2.5" system with cross pipe already on there, was hoping to still use it, but the old headers i had had a bend to go around the chassis bits:

ThirdGen1984

iTrader: (1)

can i get some interior pics please? A rhd thirdgen sounds pretty cool, i've never seen one before

evilstuie

not really up to the interior yet, I'm making a dash out of a 1998 RHD firebird mould, but needs some bits cut to fit the screen etc in:



I haven't finished painting yet, sort of learnt how to do it with the first few coats, so once everythings in, I'll give it a quick rub back and load some more coats on and buff it out.

ThirdGen1984

iTrader: (1)

cant wait to see final product, if you dont mind me asking, how much has this conversion cost you, i might look at doing one in the future

evilstuie

Which conversion?
RHD conversion was already done when I purchased the car.
The reason for the headers issue and steering shaft conversion is because the new 400HSR motor I put in to replace the tired old 350TPI, has a set of AFR angled plug heads.
They were hitting on the old custom headers (very crappy custom headers) and needed something to clear angled plug heads and the RHD steering shaft.

The other conversion have been the mod to put the KITT scanner on the front bumper, so I plastic welded out the peak on the nose and made it flat.
Then the 0411PCM OBD2 conversion cost me maybe $600-700 for all the parts, sensors and harnesses etc.
And then the dash conversion....not too sure yet, we'll see how i go upholstering it and making everything I want in it fit. Hopefull I don't need to run a second alternator to run the electronics LOL :P

ThirdGen1984

iTrader: (1)

i was referring to the RHD conversion, sounds pretty interesting, maybe one day ill buy a roller and attempt it

ThirdGen1984

iTrader: (1)

sounds like an interesting build, got my sub, and i dont think you will need 2 alternators, maybe just 1 big one like from a truck or something XD XD

evilstuie

Yeah, well I'm running 2 alpine subs, 2 amps, head unit, in-car pc, 2x10" touch screens, 1000watt inverter, in cabin dome camera, 2x IR front cameras, rear camera, gps, the head unit for the stereo, and god knows what else before I finish assembling everything.

I've got a truck battery in the engine bay which I had to mod a bit to fit, and then running a secondary battery in the boot, and was thinking of putting a small battery in the dash to use as a buffer for the pc gear for hard starts, and got a 200amp alternator, so hopefully it will be able to handle it all.

I've tried to keep the total watts as low as I can, and replaced all the old wiring with new to get rid of any electrical gremlins.

Hopefully the end product will be a semi-replica of KITT with a more modern and useful dash interface. I also bought an android watch and found some software to imitate the watch communicator so I can say start and remote start the car etc.
Should be fun.

evilstuie

Here's another angle of where the cats are, and where the collector ends that I have to join together:

evilstuie

Bought a metal-cutting dropsaw, gasless mig welder and pipe bender on the weekend, so I'll have a go at making my own exhaust
Or at least the joins

evilstuie

it has begun:

evilstuie

Finally a win

w41duvernay

Has anyone had hard starting problems after installing headers in a f-body? Is this normal?

a62belair

Could you space the engine slightly more to the left for clearance? Just a thought...

w41duvernay

I don't understand why you would make your own joints. Especially when Hushpower has Y-pipes make already. It's like the guy who did my exhaust system on my Olds Acheiva SCX said, "it's better than I could make !". the Last Y-pipe I brought only cost me 40 bucks or so.

evilstuie

...Reading usually assists with understanding

Point 1. I'm in Australia
Point 2. How do you use a Y pipe on a dual exhaust system?
Point 3. The car is not yet drivable and would cost a lot to have it towed to the nearest exhaust shop.

evilstuie

I'm not sure on that one. I don't think you can change the alignment of the drivetrain without out moving everything else, trans mounts etc.

The other thought was if I could move the whole steering column over a bit more, but again I'm not sure, the less I have to worry about engineering /safety inspection stuff the better.

I'm going to take a good bash at the headers this weekend, I figure the worst I can do is flatten or kink one, and if they don't fit then I have a bigger issue to worry about anyway.

peterc005

It's not going to be practical to shirt the engine over by more than a couple of mm. You might be able to loosen the engine mount bolts, take the weight off the engine and pry it across but this isn't a great solution.

I'm in a similar boat, where my car has been in parts and I just want to get it running. I gave up of headers for the time being and just bought a new Magnaflow exhaust and Y pipe.

evilstuie

Yeah I can sympathise with that.
It just needs a bit of creative thinking/violent bashing to get it in, once that's done I'm half a day of wiring away from starting it up and beginning on the tuning side.

LX_SS

I think we can all agree on that point, my car has been in the parts stage for so long to be honest i cant remember what its like to drive.

The only way i see the steering shaft being able to do anything is if a double uni joint is directly on the box placing the shaft higher than the headers.
Then again as saw from the header bash dyno test, if you have to nudge the headers to clear its not too bad of an issue. Losses are minimal at best.
Tho i'd still not like to see one of the pipes flatted to half its remaining size.

w41duvernay

Evil,
sorry for that! I just saw you joining the 2 halves of the exhaust and ASSumed you were doing a y-pipe. Most of the 3rd gen F-body cars came with a single cat. As per rules in most states in the US, you would have to run a single cat in a single cat f-body. I don't know what you're country requires.