Thread: BBC options for 71 suburban

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Hello there...new to here and not really a hot rodder but looking for some motor help. Some background, this motor is going into a 71 4x4 suburban, has 1-ton running gear, t400, 35" tires and will be a daily driver and do it all truck. It had an 89 tbi 454 in it that was pulled prior to purchase and has all wireing and ecm and plumbing still on burb and would like to keep it tbi if thats the consensus. I have a 454 that is 60 over with 346236 heads with roller rockers and comp cams 11-234-3 Extreme Energy cam. I know the heads aren't the best and looking at possibly getting some 781 heads and swapping rockers and such. I do have a set of 396 3931063 heads available but reading different posts it seems they aren't a good choice. If I stay tbi I do have an Edelbrock Performer TBI manifold. The truck forums I belong to have given me different/conflicting responses as regards to cam, heads, tbi. I am not opposed to running a carb but the efi stuff is all there. Any thoughts? Thanx

First off Welcome to CHR. That said stick around and Pat or Jerry will pick this one up.

Thanx...I googled BBC forum and this was the first one listed, I looked around a bit and saw there were a few people(including those you mentioned)that might have some info so that's why I joined.

you could use the 781 heads good heads but heads you have on the 454 may work ok would have to do with what your going after here ?i think the cam maybe ok but i use mostly rollers cam s in the bbc . i try running it with the tbi intake cam may want a chip

Just want a good motor for the rig, it's heavy. Want something that will pull the mountain passes around here and run right at my home elevation of aprox 4500'. Doing more research has me thinking the stock 454 tbi unit might not be up to the new motor? I do have performer 2.0 manifold and edelbrock 650 or 750 carbs avail. I just don't want to put one motor setup in and then need/want to change it, rather have it right while it's on the stand. I also understand that the edelbrock carbs are the best choice? I also have been giving advice on carb size from 650 to 850 depending on motor, elevation, etc.

build a 496... TBI can work will need to be tuned in just like a carb as for the AFB / edel a rework Q jet would be the best for what your looking to do

A 496 isn't in my budget right now. With the parts I have and maybe the purchase of some 781 heads, what to you reccommend? Keep it as is and run tbi? Change heads and cam and go with q-jet? If so what cam and head work?

run it like you have it now buy a intake bolt the Q jet on it run it

You think that is a better option than as is and with the tbi? Sorry for all the questions. Just want to do it right the first time with what I have. What size q-jet? Been told 750 by some and others have said 650 do to altitude.

Also, what manifold for this motor/truck combo?

there two ways to go so what do you want ? i realy can not help you much there only so much your going to do with what you have cam change may help but not alot more of a tuning thing with the TBI . i build engine s not tune in the old TBIs so you need to find some one that can help you tune it in . intake with the carb would be a dual plane performer .carb call jet or edlelbrock tell them what you have were you live and maybe they can get you close on a Qjet

I guess my main concern/question is that with the motor I have should I take advantage of the efi equipment I have or not deal with all the problems I could have with tbi size and tuning and just go with a carbed set up.