tbss intake and 243's installed
 

well added some stock 243's to the LQ4 to help the cam and the truck feels smoother. i guess from the slight bump in compression. ive read that each point moved up is about 8hp on a ~400hp motor. what about torque? best time before the heads was 13.1@103 with a 1.9 60 on toyo's. keep in mind thats full weight with spare/system/hitch. my goal is for 12's :punch:

How's drivability? Performance? We need more details :D

drivability has got better if anything, truck just feels smoother all around. x-link works like a champ no probs whatsoever with the tb. truck runs great, i need to hit the track for my 12 sec slip!

Ive been thinking of adding 243s to my lq9

good to hear Mike and good luck with the 12's.
i know it's got it for sure!

so with changing to a tbss intake, it allowed you to run a 90mm tb right?

correct the tbss intake is setup for a 90mm tb!! got one if ya need it

you guys installing these tbss intakes thought about porting them before install?
the tbss guys have gained more with porting them.andy with adm performance ports them for $199 i think.removes over 2 cups on material.
i have one for my ss but yet to install it.

oh and a side note id prob stick with the tbss throttle body and not the ls7.it has been proven on a dyno that with the ls7 tb you lose hp/tq plus a wacky throttle.

thanks man, we will see on wed night.

yep ls2 portworks or formato will port it also. i did all the research but i was hurting on time since my truck is a dd. i will get it done eventually

who makes a 90mm dbc throttle body for the tbss conversion?

Never heard about this, I ran an x-link on my "car" 90mm without any noticeable problems, you have a link with more details?

the air flow is different and causes an idle and shifting problem,now for the maggie guys its a different story :devil:
http://www.tbssowners.com/forums/showthread.php?t=4799

hey MGMC you should have bought this one :devil:
http://www.tbssowners.com/forums/showthread.php?t=6018

damn, thats a bad b*tch right there :devil:

For 99-02 trucks you can run a 90mm UMI T/B Chris thunder550 Had one.

will the trailblazer ss tb plug in to a 03 silverado or how do i get it to work ??

I was wondering the same thing about what TB to use. I think people are having to get a Dr X harness and run a Corvette throttle body or something like that. I wanted to make sure about this as I am starting to horde parts for my truck and Camaro build

you need the torquerush harness for either t-body to work.

i used the dr.x harness (torquerushdotcom) with a stock tbss 90mm throttle body that came with the manifold. I also used the tbss fuel rails with my 8.1 injectors. i got rid of the evap crap, and plugged the passenger side vent line on the valve cover. thats pretty much all to it

did you disconnect your pcv?

How does this intake compair to a L92? I have been reading on that intake and those heads and they seem pretty good. Since I am in the air about what heads I will run I am up in the air also about intake. Thanks

Sounds like a good setup, cant wait to hear how far you dip into the 12's!

Any mods needed to mate the 8.1 injectors with the TBSS rail?

nope. Just put them in.

I went to the track last night and ran a best of 12.7@105. my best time so far, before the stock 243's and tbss manifold i ran a best of 13.1@103. there was a 15 degree difference in temp at the track that really helped

congrats!!! does it "feel" faster

thats a pretty good increase man. wonder how much of it was from the increased compression of the heads? do you know what your cr is now?

Nice times! is this on street tires or did you get some slicks?

thanks guys! the run was full weight, system, spare, 1/2 tank, with street tires. i know the temp decrease helped along with the higher cr. im sure the intake/tb helped some. my cr is around ~10.2 . the stock 243's bumped me up almost 1 point in compression

Then your CR should be closer to 10.5 Did you adjust your tune at all when you did this swap?

tune adjustment was the first thing done. what formula you using to get that cr? with a stock .53 gasket i was getting 10.2

I thought stock the CR was 9.4 on the CR and the CC of the 243s was 62 cc stock. That is how I got that, unless I am wrong about the CC of the 243s. Which 8.1 injectors do you have, truck or marine? What is the duty cycle of them? I need to get some injectors but I am not sure which I will need

you are right they are 62cc. i have the reg truck injectors, @ ~80 duty cycle. whats the formula you are using, i have been using a site i got off of tech for the cr

243s are 64cc

If you have stock head gasket, should be around 10.5-10.6:1. Did you measure how far your piston comes out of the cylinder?

I just googled compression calculator, I got the CC of the heads off a book I had that breaks all the GEN III stuff down by year and vehicle. That is why I said the 243s I don't believe are any different than a set of 317s other than the combustion chamber. Everything else looks exactly the same, and 317s can be had cheap enough it might be better to get some of them and have them milled. I am going to run a worked set of 317s and see how they do

The runner length is different on the 317 to make more torque down low

That is what you would want in a truck. I don't guess it measured running length in that book I had. Just intake and exhaust CC, valve sizes, and combustion chamber CC. Everything I saw indicated to me that they were the same minus the CC of the combustion chamber. Now that I know the runner length is longer that will make me more inclined to keep them and just have them mildly worked instead of getting some 243s. I want to build a torquey motor to pull around my big truck

I dont think you can mill the 317s enough to match the compression of the 243s. I think the 243s will give you more torque down low due to the increased compression

thats what i always thought also, just smaller compression chambers. i didnt know about the runner length. when are you doing up those 317's

The block is at the machine shop now. I got the pistons and rods in yesterday. The crank, oil pan, front and rear cover, valley cover, heads and rockers I will get today or tomorrow. The cam, LS7 lifters, pushrods, headers, oil pump, timing set, and injectors I will be ordering soon. I need to deside if I will just throw in some 8.1 injectors into the truck mani or get a TBSS. I also am going to get a new torque converter matched to my set up and have a shift kit put in the tranny. I hope to have all that on the road by next summer maybe. The machine shop always runs SLOW but I am in no hurry. I want to do this one right and make everything match and work well together

How is the runner length longer? Does anybody know this for a fact... from my reading I thought the ports were identical.

You can mill 317's 71.06cc down to a 243's 64.45cc chamber but it would take somewhere around .050 to do it and you may have PTV issues depending on your cam. Also the increased compression will help torque as you said.