Which size headers should I get for my 409?I'm basically building the same motor you have and want to get the F1R kit you have later this summer(hopefully$$$).I'm selling my current 1 5/8 TTS.Should I get 1 3/4 ,1 7/8 or keep the ones I have???? Also ,have you had a chance to try the bigger injectors and cam yet?Was wondering on those too. Ihave a cam for my motor now ,but it will not work for FI(236/244/110).And last can you email me a price on a set of 6.0L head all done,I have stock LS1 heads with 2.08/1.60 but they are milled 30 thousands and don't kno0w if the compression ratio would be too high with them .Thanks!!!!!


[Modified by Slammed Vette, 4:53 PM 2/4/2004]

 

I am not Andy but read your post. Andy has the LGMotosport headers on his car and I drove the car with just the 409 and the LGs and it totally rocked. I had also been driving my TT car around that day too. I told Andy that if the C5 came from the factory with a 409 and LG headers that I would probably not even touch the car..this was based on how well it ran. But then again FI adds a whole different element.

Your heads and cam will have to go. I believe Andy's CR is 9.5:1. I would recommend going with either AFR's new heads or a set of Andy's Stage II/III Heads. I was trying to calculate your CR it looks like it is around 11.6:1...I had to assume that your Head Gasket thickness is .054 crushed..but then I took .030 off because the heads are milled, so that equates to .024. Your Compression Ratio is too high and your cam has a lot of over lap...the lsa is not the most desirable for a FI application..you at least want a 114lsa with a 110icl.

As for your Headers...they would work fine with a blower..but I can tell you right now if I had a choice of headers it would be LG's and then maybe Kooks from what I can see.

I was playing with the Chamber size of your heads I went as high as 74cc and still could not get under 11:1 CR because your heads are milled..I assumed your bore size was 4.020 with a 4.00 stroke. Andy has a small cam in his 409..the same cam that is in my 346cid..but it is a mild cam with a lot of midrange torque...but really runs out around 6300 rpms. But with an F1 the hp was still climbing towards the end of his run...so obviously it overcomes in shortcomings of the cam :yesnod:

Anyway I am sure Andy will respond soon.

Have you built your short block yet? You could do it right from scratch and use a -8cc dish piston to lower your CR. I believe Andy's motor just has a
-2cc dish and then some 72cc blower heads.





[Modified by Shinobi'sZ, 9:56 PM 2/4/2004]

 

Haven't assembled it yet.It's a Lunati rotating assembly and a 6.0L iron block sitting in my garage in boxes right now.Soon as I saw Andy's post on the F1r I knew that's what I wanted to do.So it looks like a set of LG's for me.Hope they will bolt up to my Corsa TI exhaust.I guess I'll be getting new heads and just selling the motor I have in the car now complete.Hopefully make some money back on that.Wondering what cam I should go with.The 224/224 or something a lil bigger.I know the one I got now is no good for FI.Thanks for answering my ?'s.

 

I like the LG headers. Easy to install and fit great. They obviously perform as advertised.
I still have a few sets left at the sale price.
Give me a call anytime. We can figure out just what you need.


[Modified by Andy@AandACorvette, 5:28 PM 2/5/2004]