Looking for advice: Carb vs EFI

[69FJ40NJ]

So I have a 69 FJ40 with a SBC 350, 400 trans, electric fuel pump. I have been thinking about going to a qjet carb, 750 cfm. Or, do I bit the bullet and do a Sniper II EFI?

I would like to drive this a few times a week around town and to and from work.

Any info and/or advice, good or bad would be greatly appreciated.

Thanks

DM3

 

[pb4ugo]

I can't speak to efi, because I've been running a qjet since the early 90's. Efi has always been on my list to do, but obviously it gets pushed down that list as other mods become more intriguing. It's now gotten to the point where efi is probably off my list and am fine with my qjet. I run qjets on 2 40's and 1 on our boat. My 1st 40 was built to be a driver and a capable trail rig. Thru the yrs its had carb issues but nothing that would leave on the side of the road or trail. I've also become pretty good working on them. Once they're set up to my liking I rarely have to do anything with them. I recently been driving my other 40. It's setup to be more a driver and drive it a lot
I've been playing with the qjet to get a finer tune. It runs a performs great. Keep in mind most qjets on the market have a generic build so they work on many applications and most a/p store rebuilds are done the same way. I've found a lot of internal parts to be altered, unidentifiable and sometimes sub par, so it's hard to determine what i have, which makes it difficult to determine what i need to dial it in even better.

There's lot of good info on this site about the Sniper, but most have been installed on the stk 6 cylinder. The issues they've been working thru would be no different if it was on a v8. There's a lot of good info on these, on this site.

 

[pb4ugo]

In my effort to fine tune my street 40 i've run across info and posts from Cliff Ruggles. He evidently is a qjet guru. I've never purchased anything from him. He sells parts snd I think builds qjets for your specific needs. I'll be purchasing his book. There are other specialty shops that do the ssme.

 

[B y r o n]

Like you and many others here I have a SBC in my FJ-40. I converted from the inline 6 in my driveway and do all my own work. I've always been a hotrodder which was the driving factor for moving to the V-8 when the 6 cylinder died. Never ran a Q-Jet always been a Holley fan. Like you possibly, getting tired of dealing with carb issues over the years decided to convert to EFI. I chose to go Edelbrock EFI at the time but not sure what I would choose today.

You need to decide if you are going to do the work or hire it out. With regard to the fuel delivery are you good with modifying your gas tank or more likely to keep the pump and 2 filters outside. Do you intend to run a return fuel line or not, be aware of how your system will handle each situation before choosing. Although there are some configurations that simplify this they are not advised for off-road use. EFI is great for adjusting AFR do to altitude changes or other atmospheric reasons. Last but not least is how much time do you want your rig down and how much money are you willing to spend on the changes.

Good luck on your decision. If you are going to stay with a carb you may want to consider the Edelbrock carb. It is a modern take on the old Carter AFB and I understand easily tuned to fit your needs.

 

[Skreddy]

A well sorted q-jet is hard to beat on a SBC (or even BBC) in my opinion. They are really big carbs but based on the design, they only supply what’s needed. If I were running an sbc in a cruiser I’d likely run a q-jet (I have on 3 previous cruisers).

 

[texcwa]

I had been running a Holley 600 cfm for over 10 years on my sbc. Got tired of constant tuning and hard cold starts. Just installed my Sniper and night and day difference, it unleashed all the power my sbc has. No more cold start issues and throttle response is 200% better.

Had some issues with interference with my older MSD distributor so bit the bullet one more time and got their Hyperspark ignition system, WOW what a difference, no more play with the timing, vacuum holds steady and can tune on the fly.

The difference with EFI is more then the difference between going from my carbureted sbc from the old F 6.

 

[jembourbe]

The best thing about EFI is the cold start/warmup and relative lack of maintenance.

 

[90WT]

I like carbs. No experience with Sniper. If you stay carbureted, consider adding a permanent vacuum gage and AFR gage (wide band O2 sensor). It made dialing in the jetting, etc, way easier to tweak for driveability.

 

[pb4ugo]

The difference with EFI is more then the difference between going from my carbureted sbc from the old F 6.

If that's the case, then you had a lot of underlying issues. One of them probably started with an H.

I don't doubt fi is more responsive than a carb, ive seen it, but the difference between V8 an a 6 cylinder in real life situations is considerable. The problem I have with fi, is its limitations at the top end and fueling, but that's the hot rodder in me. The other issue for me, is when a component within the fi system fails. I've witnessed it many times on the trail. Their weekend was cut short.

 

[Firemedic831]

I would only consider the Sniper 2. Do not even waste your time with a 1

 

[rlong]

One thing that is sometimes missed when comparing is that fuel injection can compensate for altitude changes. In Colorado it’s not uncommon to start at 5,000 feet and end up wheeling at 11,000 - 12,000 feet altitude. This is a clear advantage for EFI.

 

[69FJ40NJ]

Thanks all, I think I will go carb for now. Maybe EFI down the road.

Thanks again

 

[Firemedic831]

Thanks all, I think I will go carb for now. Maybe EFI down the road.

Thanks again

The Edlebrock avs2 is supposed to be about the best for Offroad . I just took my sniper off ( was having issues with it ) and put the edlebrock carb back on and ran the rubicon and it worked but pretty much sucked on anything steep . Will be installing the Sniper2 this week

 

[65swb45]

Also a big fan of the Qjet in the SBC. Time-tested design that others have been willing to copy, and that means something too.

Often overlooked with both the Qjets and the Aisan carbs on the stock rigs is how critical the proper float level is. And you won’t really understand all the mechanics of it unless/until you’re inside it. Too high and you’re going to have fuel slosh/flooding. Too low and you’re going to have problems with the accelerator pump and starvation under hard acceleration.

On my SBC, I reached a successful compromise by setting the float level lower than spec so that I wouldn’t have flood stumbling off camber and on inclines, and installed an inline high pressure Holley electric pump with a guage and toggle switch to momentarily boost delivery on the highway when hard acceleration was likelier to drain the fuel bowl because of the lower float level. That did the trick for me. YMMV.

 

[gom2109]

Why not a 3fe cyl head with all the intake manifold and injectors on a 2f block?