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#351 Shtstr

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Posted 15 April 2023 - 05:25 PM

Some better photos to show the gap between the pipes and tank.

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#352 Shtstr

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Posted 15 April 2023 - 05:41 PM

The gap between the rail and the pipe is about 10mm as per the bottel cap on each side. There will be a hanger at this location to stop it from hitting the rail.

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#353 Bigfella237

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Posted 15 April 2023 - 07:27 PM

What's with the tyres sitting hard up against the flares? Are they yet to be 'massaged'?

 

Some better photos to show the gap between the pipes and tank.

post-9674-0-47489600-1681543509.jpg

 


 



#354 Shtstr

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Posted 15 April 2023 - 11:28 PM

What's with the tyres sitting hard up against the flares? Are they yet to be 'massaged'?

They are yet to be set up fully plus the wheels are a bigger diameter than the ones that will be fitted to the car.
They are actually just off the tyre atm.

#355 Hatchback13

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Posted 17 April 2023 - 08:31 PM

Some very nice work, one of my next things to do so inspiring. Cheers



#356 Shtstr

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Posted 18 April 2023 - 05:31 PM

What's with the tyres sitting hard up against the flares? Are they yet to be 'massaged'?
 

 

 


Here ya go. I put a bolt in the back lower hole of the flares. Also the tyres are 670mm tall and the ones that will be on the car when finished will only be 635.
So 35mm smaller in diameter. This will add 17mm extra to the clearance. Currently about 10 to 15mm gap. Without measuring it.
So no issues at all.

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#357 Shtstr

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Posted 30 April 2023 - 10:01 PM

So surprised no one picked up on the mini tubs and tank shape.
Extra 70mm clearance for the wheel. Can fit a 7 inch backspace rim now. But will stick with 6.5 inch to have 1 inch clearance to inner guard and suspension.
Also if you look at the photos of the tank you will notice different shape from normal now that I've pointed it out.

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#358 Shiney005

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Posted 01 May 2023 - 08:04 AM

I noticed how different the angles on the tank were to mine, but didn't figure out why.  



#359 Shtstr

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Posted 01 May 2023 - 07:51 PM

I noticed how different the angles on the tank were to mine, but didn't figure out why.  


The angle is the same but starting point for it has moved.
Normally the flat sides are 320mm mine are only 180mm.
That way it clears the modified chassis rail and mini tubs.
This also gives me extra room for the exhaust pipes to clear the tank and wheels.

#360 Shtstr

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Posted 27 August 2023 - 09:00 PM

Well haven't posted on here for a while because life and health is shave been in the way of progress.
But tomorrow I'm going to grab some ls1 heads to do some research with for porting my own. As I can't afford to spend 4k on a set of aftermarket cnc heads when money can be spent better elsewhere.
So the plan is to get the ls1 241 heads tomorrow and have them cut up for a cross section view so I can see how thick the heads are in certain areas for porting.
Given that the 241 heads are 10cc smaller than the popular ls 243 heads on the intake port and match them for flow at .200 lift. I don't think it will take a lot to get the 241 heads to flow as good or even better than the stock ls 243 castings.
Time will tell I guess.

#361 yel327

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Posted 27 August 2023 - 09:32 PM

Weren’t the C4B 300kW engines in VT, VX and V2 built using CNC ported 241 heads? Those things went like stink until they chewed out the cam.

#362 Shiney005

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Posted 28 August 2023 - 11:40 AM

C4B was in the Calloway as well wasn't it?



#363 yel327

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Posted 28 August 2023 - 07:32 PM

I think C4B was the RPO code for the HSV 300kW engine. The heads I think were used on other Callaway projects. See below, they screwed up calling the HSV coupe a Monaro but the rest looks right.

https://www.callaway...laway-cars/c13/

#364 Shtstr

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Posted 28 August 2023 - 10:29 PM

Weren’t the C4B 300kW engines in VT, VX and V2 built using CNC ported 241 heads? Those things went like stink until they chewed out the cam.

Weren’t the C4B 300kW engines in VT, VX and V2 built using CNC ported 241 heads? Those things went like stink until they chewed out the cam.

Yes they were ported 241 heads. All ported by hand I think not cnc. They are stamped C4B but anyone can stamp that into a head.

#365 Shtstr

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Posted 28 August 2023 - 10:37 PM

Well picked up a set of 241 heads for $50 today to cut up.
Looking at the ports they won't require a lot of work to get them flowing really well. Use to do all our own red motor heads and 308 pre efi and efi heads 25 years ago so not new to porting heads and getting good results.
Last set of vn efi heads I did was in 2001/2 from memory. They went on a 355 stroker that made 457rwhp way back then.
New to the LS stuff but ports are just ports.
Only the thickness is different with alloy heads.
Drilled a hole in the deck this afternoon to see how thick the deck is on them.
They have plenty of meat to skim them down after I reshape the chamber to achieve my target of 66cc for my desired compression ratio of 11.51 to 1.
My dome top pistons have valve reliefs so piston to valve clearance isn't a problem.

#366 yel327

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Posted 29 August 2023 - 06:49 AM

Yes they were ported 241 heads. All ported by hand I think not cnc. They are stamped C4B but anyone can stamp that into a head.

 

They were CNC done according to the Callaway site - they weren't just on C4B HSV engines, Callaway used them on lots of other applications. Point was those engines were 400hp mafless and still emissions compliant. So the heads must work OK if ported right.



#367 Shtstr

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Posted 30 August 2023 - 04:03 PM

They were CNC done according to the Callaway site - they weren't just on C4B HSV engines, Callaway used them on lots of other applications. Point was those engines were 400hp mafless and still emissions compliant. So the heads must work OK if ported right.

I've seen some flow numbers a while ago. They didn't look like anything amazing from memory around the 260cfm. The ls6 243 heads flow 263cfm from factory too.
Also the cam for that Callaway engine is a 212 222@50 with 56 569 lift. The engine compression ratio was also slightly lower than a ls1 at 9.95 to 1 static compression ratio.

#368 Shtstr

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Posted 30 August 2023 - 04:13 PM

Ok scored some ls1 241 heads the other day. Had them acid dipped to clean the old oil off them and have started to cut them up.
From all the measurements I have so far you don't have much prt wall to play with. So anyone who is going to port these themselves like iam. Go gently. As the port walls are only about 4mm thick. Here is some cut away sections I've done so far for inlet and exhaust ports.
The area around the valve guide is thin. Only about 2.5mm thick so I wouldn't suggest doing much to the guide area other than streamline it slightly.

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#369 Shiney005

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Posted 31 August 2023 - 09:38 AM

Great info. Certainly isn't much meat there.



#370 Shtstr

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Posted 31 August 2023 - 06:03 PM

I'm actually quite surprised at the flow numbers for the 241 heads versus the well sort after 243 heads.
The 241 heads actually flow more on the exhaust right across the lift range and the inlets actually flow more to around 350 tho lift than the 243 heads. But once you go past the 350 tho lift the 243 flow more cfm on the inlet side.
I'm hoping to be able to get 290cfm minimum on the inlets and 230cfm on the exhaust side.
That's an increase of 50 cfm on the inlets and only 20 cfm on the exhaust side.
This is going to be more interesting than I first thought

#371 Shtstr

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Posted 01 September 2023 - 07:03 PM

Jumped on the lathe today and machined down an inlet valve and exhaust valve to 89% intake and 86% exhaust valve size for a guide for when I port the bowl area.
I'm actually surprised to how close the factory made them. I'd say within 3 to 4% of the perfect size of 89 to 90% and 85 to 87% for inlet and exhaust ports.

#372 Shtstr

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Posted 11 September 2023 - 07:57 PM

Well can't open them up anymore than that. The valve is machined down to 88.5% of the intake valve size.
Been talking to some people in the USA who do these for a living.
They recon its about where it need to be and should flow over 300cfm with good low lift numbers and air speed.

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#373 Shtstr

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Posted 08 December 2023 - 01:24 PM

After playing with the heads I've changed the Camshaft specification around from what comp cams has 54 458 11 cam. To the specification I wanted in the first place with a tighter lsa.
This thing will sound mental.
I'll ad a link to a Camshaft that is almost identical to what I have with my personal specification. But less lift and total duration but very close non the less.
So sit back and turn it up.

https://youtu.be/uL1...PnLOIyEidVOAced

#374 claysummers

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Posted 08 December 2023 - 06:27 PM

Sounds like a lumpy grey motor, meant as a compliment, but it does.


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#375 Shtstr

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Posted 08 December 2023 - 09:43 PM

Sounds like a lumpy grey motor, meant as a compliment, but it does.


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Never heard one sound like that.




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