Carbureted LSX forum - Stevecritt LQ9 L92 Build Thread.

Ok, starting a build thread. Just got the short block together the other night. Got lots of pics I'm going to post a little later. Any suggestiong welcome.

Only Think I had a problem runing in to were the different toque angles on the lq9 rods. GM made 2 differnt rods. and was was 60 deg and the other was 75 i think. But I re ringed the pistons and honed the cylinders. everything looked real nice once I got it apart. Like I said I will post post pics later on this evening so you can see.

oh and I gaped my rings all around .020, I'm staying n/a and count get a number other than .014 is the lowest you can go on the 4'' bore.

just getting the block torn down and cleaned up. oil and everything inside looked pretty clean.

Once I got it all apart I cleaned up the pistons and re-ringed and honed the cylinders. Everything looks really good. Supposedly on 60-70k on the motor. Replaced the cam bearings and reused the mains and rods. Just loaded all bearing down with assembly lube and torqued and angled everything to stock specks.

gone work on getting these mounted to check my push rod length.

Got a new Harwood 2.5 hood, and intake mani and 810cfm custom carb from the carb shop.

Tell us about your combo Steve. Who's heads? What cam? etc.

they are cnc pro- comps. from a company in california Walker racing group. they sent me a flow sheet of 380 cfm something at 700 lift. and 360 cfm or so at 600.

Cam is from EPS 234/246 601/615 @.05

Ive got a set up 1 7/8 headers from tsp, and their monster 4 single dist good to 700 something torque, just bought a set of arp head studs, and the mds 6010

Wow. That thing is going to be a monster. Are you going to flycut the pistons yourself?

yeah lol I certainly hope so. Hoping to get to 500whp na or somewhere close. And with a set af DR hoping to break in the the high 10's but I'm not gettin my hopes up.

I was thinking about fly cutting my self, but I'm going to look at the cost of the tool and then the cost to have the machine shop do it.

I'm going to check the clearance though next weekend. I think geoff said it might fit. but I'm taking no chances.

That will be fun to drive with a stick shift. What does it weigh?

Ohhh nose, carbed 4th gen!

full weight minus ac. so probably about 3500 give or take. well. I did get the light weight fly wheel. so minus 30lbs.

lol and yes. I had an lt1 383 fi. and I'm ready for the carb world.

ok I Installed a few head studs and just light torqued them to check the push rod length. If you look at the bottom picture I used the stock push rod (left) and the comp with 2 turns @.050 each turn (right).

You can tell the comp was a little more center. Do you think looking at this its worth the extra .10 length on the push rod?

well it looks like the build is starting over.... I'm going with a 408 bottom end. Does any one want to buy a lq9 bottom end with new rings??

ok now I'm waiting for the assembly to get here then we will start back up on the motor. In the mean time. I'm in the process of sanding down the car for paint. I will start documenting the project from there and pick back up on the new tsp 408 stroker.

What prompted the upgrade?

lol having to take the pistons back out to take them to a machine shop and to have them cut. and then having to take off all my springs to mark the pistons for cutting. So I was what the heck, just go big.

Little update I dropped my block off to have it machined and the short block assembled with the new lunati 408 forged bottom end. GOt the -10cc pistons so I believe I will be around 11-1 com or so. Should have it back this week. and I will get some pics posted. and start working on getting the motor in the car, after I swap out input shafts in the lt1 tranny.

What's a ballpark $$$ on the Lunati 408 kit? What all is included?

2400 somthing. That came with all bearings, rings, balanced and shipped... regardless its an as ton of dough... I'm really hoping to get over the 500whp mark with this set up.

2400 somthing. That came with all bearings, rings, balanced and shipped.

Wow that is a lot cheaper than I have seen for that kit. Got a link?

texas speed.

its also got the arp 2000 bolts. Which ever one the good ones are. I think its the 2000, and of course h-beams, and wiseco pistons.

Ok quick update. I got the New lunati 408 back from the machine shop friday and got it all put together today. I will post some pics tomorrow. just have to get my new input shaft for the tranny and its all going back together and going in the car. Can't wait to see it run.

Ok so I have been doing some contemplating and decided it would be best for me to just plumb new fuel system. My stock lines are 3/8 and 5/16. I have to up the return no matter what I do, so I figured I might as well just run 1/2 in feed and return and call it a day, and still use my aeromotive regulator....

some random pics

some of the motor.

Ok, well I've got the motor in the car for a mock set up so I could run the fuel system and cut away the cowl for the carb to fit. Only thing I'm really waiting on to get this all together is the new input shaft. which has been on back order for the past 3 weeks.

there was really no where to mount the fuel pump with out clearance issues, so I cut a hole underneath the back seat so I could fit it up underneath the car.

Cutting the fuel hose caused a bit of a problem. I found out You could only cut it with a chop saw or a small cutt of wheel. I believe they also make another special tool to cut it. anything thing else just frays the SS braided wire all the heck.

I just took out the old fuel pump intake assembly and cut off all the old tubes and welded up the holes and drilled another hole to put in a bulk head for the feed line. Ill do the same for the return. just a small mod to save a little cash.

few more pictures of the cowl cut out and the fuel lines after being cut and hose ends put on.

All that in a bag of truck accessories, lol. Looks good man, should be
Really entering that "excitement" phase.

Lol yeah its starting to get there. Just took the motor back out to paint some more of the accessories and put on the fly wheel. About to run the return line. and hopefully crank the motor this weekend.

Sweet. See if you can get a idle clip, I would like to see how it sounds.

Steve,

What clutch components are those? Can you get me a measurement on the bore (ID) of the throwout bearing?

Thanks!

Yeah, its a monster stage 4 clutch from Texas Speed. I'll get back with the bearing.

Update. I finally got the motor mounted and bolted down for good and the t56 buttoned up behind it. I had to modify the trans mounting bracket due to the longer gto bell housing. spark plugs in, headers on, made some custom brackets and welded them on the frame so I can mount the radiator up strait instead of the stock tilt. lots more room to move around now with that little mod. I got all the radiator hoses hooked up and plumed the steam tube to the radiator. I got the return lines and feed lines ran.

Gettin really close to the first start up. still have to fab a pickup tube for the tank and run all the wiring to the fuel pump, starter, msd and what ever else I have to do.

Well I had a long day of wiring all the new gauges, and finding a good spot to put the water temp. But it work out. lol I will post pics, it ended up being quite convenient. I Ran into an abundant problem I think most all of us have with the npt and metric fitting. For the oil line I just drilled out the stock sending unit and tapped it and it worked GREAT!.

As for the water temp I had an extra port at the bottom of the lt1 radiator that ls1's dont have and I routed it into there. I just couldn't allow my self to drill and re tap those $2k heads... lol.

And I ended up wiring my starter to my cigarette lighter. And set up my auto meter wide band.

Oil is in and coolant is in the radiator. Just waiting on my new starter to get here Monday and the ls1 style spark plug boot ends summit left out of my order.. ( I had to buy and make custom length wires due to my valve covers) :( then the car will be RUNING!

Tomorrow I'm going to finish the back lighting wiring for the gauges and set up my throttle linkage and take and post some more pictures.

Here are some pics of:

- Radiator mod, (standing straight up)
- oil pressure sending unit drilled out with a 3/8 bit
- water pressure gauge plugged into radiator hose.
- and I made a small mount for the fuel regulator that got it much closer to the carb.

well I finally got it started. I will see If I can post a vid of it later. Got a couple issues. I can tell the car is getting to hot and the temp gauge is not reading it. Don't know if the thermostat is not opening or what. and I also noticed some vinting coming out of the dipsitck. the cylinder heads I have do not have a pcv. Could that be why??

or I guess it could be from the rings not seating yet. It sounds super awesome!! But AFR gauge is reading lean. like 16 and 17.

I would get some type of pcv valve and or breather for it. They sell breathers that screw in where the oil cap goes. Ive seen people just drill a hole in the aftermarket valve covers, get a rubber grommet and use an old sbc pcv valve.

yea I got it runing to the highest inlet on the radiator.

yea I got it runing to the highest inlet on the radiator.

lol, thats why I edited my post, saw it in the pic. Maybe it just has some air in it. I always liked the bleeder screws on the 3800's that let you bleed the air out. Hard to say without a guage though?

Ive got a gauge. just have to re evaluate where I have it plugged

Love the build, man. I did a 408 stroker earlier this year and it flies. I bit the bullet on my LH head and retapped it to a 1/4NPT for my temp gauge. Rads are always going to be way cooler than the engine itself.

thanks man. Yea I'm looking in to an adapter right now so Hopefully I dont have to tap the head. I have to get the ls1 water pump too. The inlet on the truck pump is too high... bummer.

Ok well I changed to an ls1 water pump and now the highest point is the radiator cap. so I got the water system set. I let the car Idle for about 10 min and it didn't get over 180 so I think its cooling just fine. I will get an idle clip up here by tomorrow. It sounds awesome!!. super choppy. but nice.

I just put on my TSP true duals and the car sounds WAY better!. I'm going to get an idle clip tomorrow. I'm just trying to check everything over and look for leaks before I take it out. All I have to do is bleed the clutch and brakes and It should be ready to take out for a spin.