RAACCR

I installed my heads and cam last week. The Patriot 243 heads were just too good of a deal to pass up. Great quality and customer service as well...thanks Gunnar! I had them deck the heads to 62cc, and used .040" Cometics from Thunder Racing. The cam is a Comp XER 224/228 111 +2 (.581"/.588" lift) and the pushrods are 7.400". I have been following the advice of Patrick G and Predator-Z...this combination gave me the valve events and DCR that I was looking for. I added a LS6 intake, ported LS6 oil pump, LS2 timing chain, Powerbond underdrive pulley with ATI pin kit, and Meziere EWP with 160* thermostat. I already had a Vararam, ported stock throttle body, and descreened and ported MAF. I added American Racing 1 3/4" headers with off-road x-pipe to my existing Z06 Ti mufflers. I have been tuning the car with HP Tuners...the tune-up is still a work in progress, but the difference is night and day vs. stock! The swap went very well, thanks to the advice on LS1tech.com and instructions on LS1howto.com

Thanks,
Rob

LS1Aggie09

iTrader: (25)

sounds like everything went smoothly! good job, post up some dyno #'s once you get done fiddling with the tuning software

JuStIn_Ws6

iTrader: (6)

Yeah let's see that dyno!

N4cer

iTrader: (11)

Screw the dyno. Let's see some track times!

RAACCR

I agree...it may eventually wind up on a dyno after I get the tune fully dialed in, but the track times will tell the real story. With just a Vararam, ported throttle body & MAF, MT Drag Radials and Z06 Ti mufflers, it had ET'd as quick as 12.311, and trapped as high as 113.30 mph. SOTP tells me its a whole lot faster now

LS1Aggie09

iTrader: (25)

damn..track times would be nice as well...11.0 maybe?

RAACCR

I'd guess it should drop about a full second and pick up around 10 mph in the traps. When I get bored with that, I can always put the bottle on it and join the 10 second club. (Gonna' need to replace the stock clutch sometime soon...I don't think its going to like the extra ponies.)

pdd

iTrader: (3)

nice setup

Smitty's '04 GTO

iTrader: (5)

How much did you mill the 243's to achieve 62cc?

Nice set up, have fun with it!

bsf

iTrader: (7)

What do/did you calculate your DCR to be? My un-milled Patriot LS6 heads and 0.045” Cometics are setting in a pile of performance parts. I am waiting on the 224/228 .581/.588 110+0 cam I ordered from Thunder Racing around Thanksgiving. Based on my calculations, using advertised specs for my stock engine and assuming 63.6cc chamber volume, I figured I would have a DCR of ~8.6. Actually, choosing a setup w/ that high of DCR makes me a little nervous.

RAACCR

I'm guessing around .020"ish? Gunnar could tell you exactly how much they need to mill them to get the chambers down to that size...I just asked for 62cc and he took care of it from there. (PTV clearance wasn't a concern for me since my cam isn't huge, so it wasn't critical for me to know the exact amount he cut 'em.)

RAACCR

I played around with a couple of different DCR calculators; depending on which one I used, I got DCR numbers in the 8.7:1 - 8.9:1 range. These calculators are like dynos and flowbenches...they work best when you compare results from the same calculator. I started running some different proven combinations through them, and tried to get similar numbers for my combo. Due to the fact that I have a '99 motor (with poor oiling and crappy rod bolts), I wanted to keep the shift points to a maximum of 6500rpm. That lead me to a IVC (@ .050") of 41* ABDC. Yes, my DCR appears toward the higher side of what is generally recommend, but it is also inline with plenty of other good running combinations. (Example: Patrick G has 59cc chambers, .040" Cometics, and a IVC only about 1* later than mine...he's got even more compression than I do.) I'm running on 93 octane pump gas, and although I'm still playing around with HP Tuners, I have not encountered any knock issues. I'm sure the tight quench is helping in that regard. My motor is very crisp and responsive in the lower to mid-range, and pulls like a bear up top, which is exactly what I was hoping for. I don't claim to have all the answers, but I'm smart enough to find out what works and copy it

bsf

iTrader: (7)

I guess I should be fine with my setup. I am not going for max effort. I have not decided whether I will pay for a dyno tune or buy hardware & software to do it myself. By any chance did you measure PTV clearance?

I am glad you started this thread. Congratulations on the success of your H/C job.

CHRISPY

sounds like a great combo congrats

N4cer

iTrader: (11)

8.6 makes you nervous? About what? 8.5-8.8 is the proper range, isn't it?

RAACCR

Thanks..everything went pretty easy; I just followed the advice of LS1tech.com and the directions on LS1howto.com . I never measured PTV; every indication was that I'd have tons of clearance with my little cam, especially with the stock sized valves.

I bought the HP Tuners Professional Suite, and I'm very happy with it. I have never used any LSx series tuning software before, (although I have some background with DFI, Felpro/Speedpro/FAST), but it was very easy to figure out. I was able to copy a VE table from a file in their online tune repository, and tweaked everything else myself. Although I had zero prior experience, I had the car running very nicely within the first hour. I have mostly been working on fine tuning the driveability, and I'll move onto some wideband tuning shortly. But, with the online tools on the HP Tuners website, I'm proof that even a beginner can do it. Don't be afraid to be a do-it-yourself tuner.

bsf

iTrader: (7)

Before I bought my TA last summer, I could not have even explained what a camshaft was. I have been operating under the assumption that anything above 8.6 is approaching “eyebrow raising” territory.

bsf

iTrader: (7)

That is encouraging. I have only researched tuning a little. I am not sure what software package I would go with, or what hardware I would buy: wideband, laptop, etc. I have not found much of a tune repository for EFI Live. I have gone to HP Tuners website, but if I remember correctly, you cannot gain access to their tune collection without having purchased their stuff. It sure can get expensive.

Gunnar@Patriot

iTrader: (20)

Glad the heads are doing well for you. Keep us posted on your numbers and times.

1997bird

iTrader: (2)

For every .006" flat milled you lose 1 cc.