What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

Whats a good offroad carb

G

gm500hprat

1/2 ton status
Joined
Feb 28, 2005
Posts
196
Reaction score
0
Location
anaheim, ca
All of the cfm calculators I check say I need at least 850cfm. I have a 500 hp 454 that was built by clay smith racing in buena park. I have it in a tube buggy I'm building. I know the quadrajet is good for offroading but I've only found it to 800 cfm, I know edelbrock used to make an 850 but they dont make it any more and dont sell it. Are there any others? I will be mostly sand duning and riding the dezert portion of johnson valley. Thanks in advance.
 
If you are that worried about sacrificing horsepower buy a Jet Performance stage 2 or 3 Q-jet. I am running a Stage 2 Jet Perf quadrajet on a 540 Caddy stroker. I have no problems gettting enough fuel until I get over 5500 RPM. It is box stock except for the float. I changed it in favor of one with a different shape. I did that to get it run better on very steep inclines. If I wanted to rev higher I could change jets & metering rods, but I really don't need to rev higher than that anyway.
 
if you gonna use it only in sand dunes and dezert
get a holley 4150 HP
I am using Pro-Systems built 950 HP carb
and it runs flawlessly
02062009145.jpg


I've used Edeljunk 1407 750cfm previously and it won't stay in tune and it doesn't like bumpy roads in the desert
I've also used a stock Q-Jet ( on a stock 355 SBC ) it was OK but when I upgraded to a mild 454 BBC I went with Pro-Systems based on JDNobodi advice

a lot of local guys are using Holley HPs with great success
 
Thanks for all the posts, I have had 3 different Holly's on this engine since I got it and it has never run right. I had one from the carb shop and one from a local guy, the current one I cant even go over a whoop at 5 mph with out it going into zombie land.

I had good luck with my quads when this truck had a 300hp 350. But didnt know if they folwed enough for the Big Block.
 
GMC500 said:
if you gonna use it only in sand dunes and dezert
get a holley 4150 HP
I am using Pro-Systems built 950 HP carb
and it runs flawlessly
02062009145.jpg


I've used Edeljunk 1407 750cfm previously and it won't stay in tune and it doesn't like bumpy roads in the desert
I've also used a stock Q-Jet ( on a stock 355 SBC ) it was OK but when I upgraded to a mild 454 BBC I went with Pro-Systems based on JDNobodi advice

a lot of local guys are using Holley HPs with great success
Click to expand...

Have you side hilled this carb in the dunes at all? How much did it run?
Thanks for the info. I'll look up Pro-Systems on the net.
 
gm500hprat said:
Have you side hilled this carb in the dunes at all? How much did it run?
Thanks for the info. I'll look up Pro-Systems on the net.
Click to expand...

driving in any angle is perfect
I've let it idle for a long time on a hill and it was OK also
I didn't test it idling on a side hill though

I paid $690 for mine
check with Patrick @ Pro-Systems for pricing he is a really nice guy
you might buy used Holley 4150 core from E-Bay and let him build it for you
 
GMC500 said:
driving in any angle is perfect
I've let it idle for a long time on a hill and it was OK also
I didn't test it idling on a side hill though

I paid $690 for mine
check with Patrick @ Pro-Systems for pricing he is a really nice guy
you might buy used Holley 4150 core from E-Bay and let him build it for you
Click to expand...

Holy god $700 could get you an entire TBI setup from an 87+ truck.

I agree here, go EFI or go propane.
 
gm500hprat said:
Give me some info on EFI, links, costs, can they be clibrated for a decent cam and HP.
Click to expand...

TBI, the cheap way to go to fuel injection, is not going to come close to meeting your HP or cam requirements.

Any fuel injection option for you is going to be spendy.

Seriously, buy a Q-jet (750 or 800 CFM, the big one has 50 more CFM in the primaries and is found on big blocks generally). Buy this book and modify it to what you need. There isn't a better carb for a wheelin' truck than a Q-jet, period.

Actually I have that book and am switching to propane soon so contact me if you're interested and I'll make you a deal on the book for cheap.
 
38377k5 said:
TBI, the cheap way to go to fuel injection, is not going to come close to meeting your HP or cam requirements.

Any fuel injection option for you is going to be spendy.

Seriously, buy a Q-jet (750 or 800 CFM, the big one has 50 more CFM in the primaries and is found on big blocks generally). Buy this book and modify it to what you need. There isn't a better carb for a wheelin' truck than a Q-jet, period.

Actually I have that book and am switching to propane soon so contact me if you're interested and I'll make you a deal on the book for cheap.
Click to expand...

http://www.amazon.com/Rebuild-Modif...=sr_1_1?ie=UTF8&s=books&qid=1273464953&sr=1-1

This one too

Stomis said:
Holy god $700 could get you an entire TBI setup from an 87+ truck.

I agree here, go EFI or go propane.
Click to expand...

I wish my TPI swap would cost that cheap.

The way I want to do it is with a LS1 pcm so I can tune with my EFI Live V2.

The crank reluctor alone is about $375 lol
 
Stomis said:
Holy god $700 could get you an entire TBI setup from an 87+ truck.

I agree here, go EFI or go propane.
Click to expand...

EFI will cost much more than this
I am talking about 454-496 cid engines with big cams
for $700 I got a carb that is perfectly calibrated for my engine and needs very minimal tuning or no tuning at all
I can still use my stock mechanical fuel pump or upgrade to a bigger one for around $100

EFI setups for High Performance BBCs are very expensive $$$
and they need to be tuned properly ( again $$$ expensive )
also don't forget that a complete makeover of fuel system is required ( electric fuel pump, high pressure lines, regulator, 2 EFI tanks, high pressure diverter valve for the dual tanks ) $$$

also for a truck that is used only on every other weekend
and gas prices $0.16/liter 95 Octane & $0.12/liter 91 Octane :eek1:
I don't need the benefits of EFI
hell, WTF is EFI :D
 
The caluclators are just basic formulas thrown around.

Several years back Hot Rod did a test on a motor, I think it was in fact a big block. They put the a ton of carbs on the motor all the way from a 500 cfm up to a 1200 cfm dominator.

The real surprise of the test the600 cfm carb made nearly as much power as the carb the motor was actually "supposed" to have. The carbs that were too large cost some power but all the carbs made very close to the same power.

You can get 800 cfm quadrajets, You could probably get them to flow about 825 with just some smoothing out of certain things.

Thing here is this the best off road carb, period, end of story. It will work best for what you want to do. Who cares if you are making another 20 hp if you can't keep it running it doesn't matter if you are making another 100 hp.

I really doubt the quad will cost you much power, having your ignition advance just off will more than likely cost you more power than having a carb that can flow another 50 cfm
 
buefchris said:
Yes, I know Mike from way back.
Click to expand...

Ok, thats what I thought, I grew up in the neighborhood. I live just around the corner from you. I'm a friend of Mike's nephew Brad. I used to drive my k15 with grape metallic scallops through the neighborhood in high school, probably way to fast. ANyways small world, I'll have to stop by next time I drive by and you guys are working on your Blazer in the garage. My buggy should be driving soon, even with the crappy carb. Its been sitting for 3 years i dont care if I just drive it around the block, I cant wait to get it to that point.
 
You must log in or register to reply here.

Latest Posts

Top Bottom