LQ4 with a carb for an offroad buggy. Looking for some advice.
02-07-2017, 09:17 PM
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LQ4 with a carb for an offroad buggy. Looking for some advice. I have an LQ4 out of a 2005 Chevy 2500, it has 85k on it.
The engine is completely stock for now but I would like to add a nice cam... not sure what I should be looking at for this and would like some recommendations.
It will be going into a tube chassis buggy with a TH400/NP205 (most likely a doubler between the trans and t-case), 1 Ton axles and 40" - 42" tires.
I'm planning on using a Holley Off-Road Truck Avenger 670 CFM Carb and an MSD 6010 Ignition Controller. Holley offers the same carburetor in 770 CFM, should I go with the 770 CFM one vs. the 670 CFM version?
I've been looking at the Edelbrock Performer RPM Intake Manifold (P/N: 71187). It's the only intake that I've found that fits cathedral port heads and has a spot for the MAP sensor to plug into (from what I understand keeping the MAP sensor is important for the vacuum advance when using the MSD 6010). I would prefer to stick with a dual plane intake, is there another intake that I've overlooked?
Also, I'm looking for quality fasteners to secure the intake manifold down to the heads, does ARP offer some bolts for this application (Edelbrock 71187 to be specific)?
I'm just trying to get a list of what I need to buy going so I can start ordering things. Any help or suggestions would be greatly appreciated.
Thanks,
Nick
The engine is completely stock for now but I would like to add a nice cam... not sure what I should be looking at for this and would like some recommendations.
It will be going into a tube chassis buggy with a TH400/NP205 (most likely a doubler between the trans and t-case), 1 Ton axles and 40" - 42" tires.
I'm planning on using a Holley Off-Road Truck Avenger 670 CFM Carb and an MSD 6010 Ignition Controller. Holley offers the same carburetor in 770 CFM, should I go with the 770 CFM one vs. the 670 CFM version?
I've been looking at the Edelbrock Performer RPM Intake Manifold (P/N: 71187). It's the only intake that I've found that fits cathedral port heads and has a spot for the MAP sensor to plug into (from what I understand keeping the MAP sensor is important for the vacuum advance when using the MSD 6010). I would prefer to stick with a dual plane intake, is there another intake that I've overlooked?
Also, I'm looking for quality fasteners to secure the intake manifold down to the heads, does ARP offer some bolts for this application (Edelbrock 71187 to be specific)?
I'm just trying to get a list of what I need to buy going so I can start ordering things. Any help or suggestions would be greatly appreciated.
Thanks,
Nick
02-08-2017, 06:52 PM
#2
Not knowing your goals for this buggy leaves many of your questions open ended, at best. Your power curve goals will determine the cam you need, but it needs to work together with the intake you choose as a system. The carb should be chosen after those two are decided. Keep in mind that you can use a MAP sensor with any intake by simply plumbing a vacuum line to it. The intake bolt specs call for torque measured in in/lbs, so don't waste your money on expensive ones. Keep in mind that ANY cam swap will require valve springs and would benefit from hardened pushrods, even if the stock length is ok.
02-08-2017, 07:32 PM
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It's going to be an offroad only vehicle. It's going to be purpose built for rock crawling, it will see time on some trails but mainly rocks.
As mentioned before cam wise I'm not surewhat I should be looking at... I know about TSP and BTR cams, a good buddy has a BTR cam in a 5.3 and it really livened the engine up.
From what I've read an LQ4 in stock form is about 300 HP and 360 Ft. Lbs. of Torque.
I'd like to get about 400 horse to the wheels and as much torque as possible.
Another option I've been throwing around is running propane (Which I'll probably go with over a carburetor). I was looking at the Edelbrock 29087, the cathedral port, single plane Victor Jr. intake.
I spoke with Cary, the owner of gotpropane.com who sells the propane kits for offroad use. He said with the propane the engine will idle the same with a single plan as it would a dual plane. I was initially only looking at dual plane intakes because I know that single plan intakes are more for high rpm applications. With crawling there will be times where the buggy is gonna be moving pretty slow and I don't want any issues out of it.
Another thing I like about that Victor Jr. intake is how it looks, lools wicked compared to the performer rpm.
I would like to mount the MSD box on the firewall or inside of the buggy and the performer has those mounting holes and a mounting tab molded into that intake... From what I've read one of the mounting holes goes into one of the runners and has to be plugged to avoid a vac leak, seems kind of pointless to have features that I wont use and that take away from the look of the engine.
Hopefully that helps! I'm a sponge when it comes to learning about wrenching so throw whatever you can at me.
As mentioned before cam wise I'm not surewhat I should be looking at... I know about TSP and BTR cams, a good buddy has a BTR cam in a 5.3 and it really livened the engine up.
From what I've read an LQ4 in stock form is about 300 HP and 360 Ft. Lbs. of Torque.
I'd like to get about 400 horse to the wheels and as much torque as possible.
Another option I've been throwing around is running propane (Which I'll probably go with over a carburetor). I was looking at the Edelbrock 29087, the cathedral port, single plane Victor Jr. intake.
I spoke with Cary, the owner of gotpropane.com who sells the propane kits for offroad use. He said with the propane the engine will idle the same with a single plan as it would a dual plane. I was initially only looking at dual plane intakes because I know that single plan intakes are more for high rpm applications. With crawling there will be times where the buggy is gonna be moving pretty slow and I don't want any issues out of it.
Another thing I like about that Victor Jr. intake is how it looks, lools wicked compared to the performer rpm.
I would like to mount the MSD box on the firewall or inside of the buggy and the performer has those mounting holes and a mounting tab molded into that intake... From what I've read one of the mounting holes goes into one of the runners and has to be plugged to avoid a vac leak, seems kind of pointless to have features that I wont use and that take away from the look of the engine.
Hopefully that helps! I'm a sponge when it comes to learning about wrenching so throw whatever you can at me.
02-10-2017, 12:44 PM
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EFI is probably better for a rock crawler, unless the
carb is especially suited to working across wide roll
angles (the regular Holleys with a big bowl and wide
spaced jets, end up with significant side-side mixture
imbalance when the body rolls).
carb is especially suited to working across wide roll
angles (the regular Holleys with a big bowl and wide
spaced jets, end up with significant side-side mixture
imbalance when the body rolls).
02-10-2017, 08:30 PM
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I ended up scoring a propane kit for dirt cheap off of ebay. The propane mixer is similar to a carburetor except that it uses propane vs. gas.
The propane can run on any angle... even upside down and it self elevates like FI, so no re-jetting and such.
Should be here soon and I will clean it up and upgrade some of the stock parts to silicone parts.
Still looking for a suggestion for a cam, higher compression works better with propane so maybe a set of 4.8l flat top pistons will help me in that area too?
The propane can run on any angle... even upside down and it self elevates like FI, so no re-jetting and such.
Should be here soon and I will clean it up and upgrade some of the stock parts to silicone parts.
Still looking for a suggestion for a cam, higher compression works better with propane so maybe a set of 4.8l flat top pistons will help me in that area too?
