[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

Yeah I’m all cool with it been public, it was just a thought I had and was wondering if it had crossed your mind at all

 

good to see others helping out with this one as well, I would help but I would probley end up  crashing the site some how lol

[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

Good stuff Gary

 

must be a relief

[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

Great so your in Byron bay and I’m in the frickin dessert

 

way to make my day lol

[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

Yes I also know a few people that have run 9s on 5002  1 3/4 picies of the shelf, but iv also seen one  of them cars gain quite a lot by goin 2 inch 4 into 1 and still drives quite fine so they where restricting it from what it was capable of doin

 

im not doin it because I’m after more power, I’m doin it because I think it’s what the combo crys for and wants

 

I’ll just go back a gear or clutch it and wait for the car to catch up to the wheels speed lol

 

I do know what every one is saying about the low torque and this is a great conversation, I really do know what delco wizard is saying and I do really appreciate the input because bigger isn’t always better

 

On the above even low to mid torque says between 1.86 – 1.987 or for 2 stepped is same and steped after 10 inches witch when converted is 1 7/8 to 2 inch just like I’m doin unless I do the cone idea witch I really like

 

even the collector suggest 3.5 or bigger and for max hp says 4 inch witch is what blakes done on his vnss i think

 

if I had a hydrolic cam in the 23# 24# that reved to 6000 rpm I would no doubt do 1 7/8 with 3inch collectors

 

[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

If you had my combo cava and where building extractors for it what size would you go ?

 

Iv iv never heard of this David guy, I’ll have to look him up

[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

Pir4te

 

Iv just had a good read of that and i must say that is the best info iv read or recieved on this site I think

 

Carnt thank you enough

 

What is the harmonics down the bottom ??

 

I take it the primary harmonics is extractor length 20 inchs

 

But the collector tail pipe? Is that saying my best results would be with a 14 inch exhaust system ??

[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

Not the verdic on this old vs

 

I know the verdict on that, its fingered

 

Im after the verdict on the senator lol

[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

Ouch

 

And the verdict is ???

[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

That awesome

 

So by that my 2 inch pipes some between 20-23 inches long and 3.5 collector is actually right on the money and for top end hp could actually be a smigion bigger

 

Ill have a good look at that when i finish work and read the collectir design and cone size it has there

 

Thanks very much pir4te

[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

The cats are 4 inch OD where 3 inch cats are 3.5 od so the count will be different

 

Also on turbo cars there is a very valad reason why they keep there primary runners and cross over pipes small

 

Its to keep air speed up to spool faster, even there cross over pipes can be down at less then 2 inch on 700 hp turbo set ups witch you wouldnt dare do on a SC car but after the turbo is a different story sometimes goin as large as 5 inch and if they really want power they will dump it just a few hundred mm after the turbo

I dont really agree there is more power or better results to be had changing mufflers over headers, i know people with 2 inch pipes on 355 engines and they clearly got gains

• This reply was modified 9 years, 6 months ago by  vs manta 218.

[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

The cleanest Ss this thing

Good to see it’s still cruising the streets

 

there is a good reason I got a $650 quick time shatter proof bell housing, the main one been I want to keep my feet

[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

I’m thinking this here has a pretty good angle I’ll try and get my 8 cones about the same as this as the angle seams pretty good

 

I have no idea what the stuff in it is as I’m not a teenager any more and been over a decade since iv been anywhere near that

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[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

Yeah big cones

about 150mm in diameter and connected to a awesome pipe

[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

Yeah that’s much better idea then running a smaller pipe into a bigger pipe that will cause trublance

 

I have watched a mate build a methanol burning  cr500 exhaust like that, he actually done loaded it then cut it out and made it, but did make custom expansion chamber with different cones pitches and sizes using your method

 

thanks very much

[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

Absolute legend 

 

best idea ever

[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

I’ll just leave this here for you to have a look at

 

check out the last pic and read from there down of you get bored and want to skip a part

 

http://www.hotrod.com/how-to/engine/1111phr-how-to-size-headers/

[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

Yeah it’s what my gut tells me to Gary

 

Ij  are you saying run a 1 7/8 for just the first straight about 35mm/ 1.5 inch or so and get the 2 inch bend on it there  ??

 

This is the main part I haven’t made up my mind on yet unless some one comes up with some hard evidence these are to big but I’m certainly not finding any

 

I have thought about running some cuts maybe 4 down about 30 mm on a 2 inch pipe and flaring it down a little just so I can get my extractor bolts in and that in it’s self would act as a scavenge  type thing or like you say a smaller pipe just a inch or 2 or make the first bend 1 7/8 something less then 8 inches I would imagine

[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

They recommend 1 7/8 for my engine in N/A form but can just cope on 1 3/4 and have a engine with 555hp over the gold pro my is based from with 525hp and that one needs 1 7/8 as a minium

 

Add boost and i have no idea lol

 

2 inch is just such a nice number though lol

[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

Them collectors

 

They go 4 into 2 for what appears to be 12 inchs then to 2

 

Iv been reading and this is a very very very good thing and in testing that i have read just yesterday compared to 4 into 1 with no ventury ( choke down then enlarged of any kind) had 12rwhp and 15 rwnm gain, no tuning no nothing, this test purely changing primary lengths and sizes and collector designs and just that gain was purely a change of collector only with same pipes

Im 99% sure this was on a 350 chev

 

May i ask where did you get them from ??

[vs manta 218Participant Vs hsv manta View build HERE Member since: March 2, 2015 Posts: 796]

^^ yeah i agree with what he said

 

And 100hp of nos while your at it

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