FiTech on an old school Big Block???
09-02-2016, 10:07 AM
#1
FiTech on an old school Big Block??? I have the original 396 in my 68 Suburban. Very mild cam, Performer intake, aluminum heads. When I bough it had a dual feed Holley on it. Old, but visibly in good shape but ran like ****. I bought a 650 Edlebrock and it runs better but still needs to be tuned. Well I just came across this FiTech setup and it looks very tempting. I hadn't really considered the other systems out there because of the price.
Well I recently spent $500 on twin O2 sensors/gauges so I can dial the carb in. Now I'm thinking that I can return them, sell the nearly new carb and buy one of these systems. Does anybody have experience with them on an old school motor? I am DDing this thing but will also use it for my camping vehicle. So pulling about 2,500 pounds while loaded up with say (just for round numbers) 1,000 pounds worth of people and gear.
So my three main concerns -
1 - Fuel economy. I am currently getting 10 or less mpg.
2 - Power. Truck feels lazy in general. I know it's not gonna be a drifting machine, but I would like to optimize what I have, getting it a bit more responsive.
3 - Adaptability. So these systems "learn" - do they stop learning? Do they adapt on the fly? Cruising at 65 mph on flat land when it's 40 degrees out commuting in the fall is a lot different then hauling a couple of tons worth of weight when it's 85 up long hills while camping.
I know I can get the carb dialed in much better, but a carb isn't going to change itself when the seasons or loads do. I am aware that these aren't as comprehensive as a full, modern system BTW. I'd like to hear what some people with experience think.
Well I recently spent $500 on twin O2 sensors/gauges so I can dial the carb in. Now I'm thinking that I can return them, sell the nearly new carb and buy one of these systems. Does anybody have experience with them on an old school motor? I am DDing this thing but will also use it for my camping vehicle. So pulling about 2,500 pounds while loaded up with say (just for round numbers) 1,000 pounds worth of people and gear.
So my three main concerns -
1 - Fuel economy. I am currently getting 10 or less mpg.
2 - Power. Truck feels lazy in general. I know it's not gonna be a drifting machine, but I would like to optimize what I have, getting it a bit more responsive.
3 - Adaptability. So these systems "learn" - do they stop learning? Do they adapt on the fly? Cruising at 65 mph on flat land when it's 40 degrees out commuting in the fall is a lot different then hauling a couple of tons worth of weight when it's 85 up long hills while camping.
I know I can get the carb dialed in much better, but a carb isn't going to change itself when the seasons or loads do. I am aware that these aren't as comprehensive as a full, modern system BTW. I'd like to hear what some people with experience think.
09-02-2016, 09:04 PM
#2
engines from the 60-80's are too old to extract modern performance. It isn't worth investing a dime because the compression is 'leaky' (poor sealing character of old engines) and poorly designed combustion chambers (for the era) no matter what you tune it with, its still going to be a fuel hog dog IMO.
Just think in 1992 chevy made 5.7L engines with 260horsepower, and now that number has risen substantially at less displacement. The extra power came from advancements in engine design, better shapes and seals and oiling character, less emission and wasted fuel and so forth. You wouldn't put a modern EFI system on a 5.7 from 92', you would just go LSx. The same applies for anything older, basically
Just think in 1992 chevy made 5.7L engines with 260horsepower, and now that number has risen substantially at less displacement. The extra power came from advancements in engine design, better shapes and seals and oiling character, less emission and wasted fuel and so forth. You wouldn't put a modern EFI system on a 5.7 from 92', you would just go LSx. The same applies for anything older, basically
09-08-2016, 07:54 AM
#4
Restricted User
FITech will work fine on an old big block.
As far as adaptability and economy, they will both be greatly improved over a carb.
Power kind of depends on a few factors. Part throttle power will likely be improved. Peak power will be a wash if the carb is properly setup.
As far as adaptability and economy, they will both be greatly improved over a carb.
Power kind of depends on a few factors. Part throttle power will likely be improved. Peak power will be a wash if the carb is properly setup.
09-08-2016, 09:16 AM
#7
I guess it's the difference between speed density and MAF??? Would a modern car do anything differently under heavy load? I know timing comes into play, at least I think it does.
As long as the AFR stays consistant that's fine???
I don't want to invest in something that I think is going to be great and have it not be. That's why I'm asking these silly questions.
As long as the AFR stays consistant that's fine???
I don't want to invest in something that I think is going to be great and have it not be. That's why I'm asking these silly questions.
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09-08-2016, 09:25 AM
#8
The carb isn't setup. Hesitates when going to WOT and my plugs are telling me that it's running lean. Which is only going to get worse as the weather is starting to turn cool. I think I'd like to NOT open the ridiculous $60 Edelbrock carb adjustment kit (it has like 6 effing parts in it), return it and just do this.
09-10-2016, 01:56 AM
#11
You really don't have a clue do you? Very little has changed from the first SBC and BBC engines over the years, Until the LS series engines they were basically the same for all those years and as far as the LS is concerned if it weren't for the improved heads there still would be very little to be gained over a 60's SBC power wise. They are still 8 cylinder non-overhead cam pushrod engines. In fact it's cheaper to do a full build a SBC or BBC then it is to do an LS series engine and not lose anything power wise. The only thing that the LS has going for it over the others is better flowing stock heads and a slightly better block design. If new engines are so much better than how do you explain this. My daughter has a 1965 6-cylinder Malibu that gets 26 mpg and that's without overdrive in fact it's a 2 speed powerglide add overdrive and I bet she would get closer to 32-34 mpg. The other motor option at the time was a 350hp 327 cubic inch engine and it still got decent gas mileage for a 2 speed powerglide car. Take that same engine and add fuel injection and cats and it will run with the same size LS engine of today. So here is my question, Why after over 50 years has so little changed? Block material is the same and the same can be said for the crank/rods/pistons/rings/pushrods and many other parts and design wise practically nothing has changed. The fact is the LS isn't 50 years advanced when compared to how everything else has advanced over the years. The biggest changes have been in fuel management and emissions and transmissions and all are easily adapted to the old engines.
PS... adding a damn turbo to everything seems to be your standard answer yet most of the time people are asking for something on a budget.. Budget and turbo should not be used in the same sentence. To do it right costs more than most people are willing to spend and It's not as simple as bolting on a turbo and driving off into the sunset.
PS... adding a damn turbo to everything seems to be your standard answer yet most of the time people are asking for something on a budget.. Budget and turbo should not be used in the same sentence. To do it right costs more than most people are willing to spend and It's not as simple as bolting on a turbo and driving off into the sunset.
Last edited by LLLosingit; 09-10-2016 at 02:11 AM.
09-10-2016, 02:07 AM
#12
Now for an answer for the OP, Yes you would see in improvement in driveability performance and economy but in the end it's still a BBC in a Suburban and it's going to like stopping for fuel on a regular basis. Dialing in the carb will get you close and probably a better way to spend your money. By the time you figure in all the costs involved in converting to EFI I don't think you would be happy with the end result and it would almost be cheaper to just by a newer used tow rig in the end.
09-10-2016, 02:11 AM
#13
You really don't have a clue do you? Very little has changed from the first SBC and BBC engines over the years, Until the LS series engines they were basically the same for all those years and as far as the LS is concerned if it weren't for the improved heads there still would be very little to be gained over a 60's SBC power wise. They are still 8 cylinder overhead cam pushrod engines. In fact it's cheaper to do a full build a SBC or BBC then it is to do an LS series engine and not lose anything power wise. The only thing that the LS has going for it over the others is better flowing stock heads and a slightly better block design. If new engines are so much better than how do you explain this. My daughter has a 1965 Malibu that gets 26 mpg and that's without overdrive in fact it's a 2 speed powerglide add overdrive and I bet she would get closer to 32-34 mpg and that's with 300 cubic inches. The other motor option at the time was a 350hp 327 cubic inch engine and it still got decent gas mileage for a 2 speed powerglide car. Take that same engine and add fuel injection and cats and it will run with the same size LS engine of today. So here is my question, Why after over 50 years has so little changed? Block material is the same and the same can be said for the crank/rods/pistons/rings/pushrods and many other parts and design wise practically nothing has changed. The fact is the LS isn't 50 years advanced when compared to how everything else has advanced over the years. The biggest changes have been in fuel management and emissions and transmissions and all are easily adapted to the old engines.
PS... adding a damn turbo to everything seems to be your standard answer yet most of the time people are asking for something on a budget.. Budget and turbo should not be used in the same sentence. To do it right costs more than most people are willing to spend and It's not as simple as bolting on a turbo and driving off into the sunset.
PS... adding a damn turbo to everything seems to be your standard answer yet most of the time people are asking for something on a budget.. Budget and turbo should not be used in the same sentence. To do it right costs more than most people are willing to spend and It's not as simple as bolting on a turbo and driving off into the sunset.
09-10-2016, 02:15 AM
#14
you have to be joking. From 1992 to 1998 is an incredible change, engines increased almost 100% in power output. anything before 1992 is a joke. Combustion chamber tech and resonance/computer simulation tech has put new engines miles ahead of anything previous. Unless you are an engineer for an automotive manufacturer I do not think you have anything worthwhile to add. The way the engine seals up compared to 92 and 98 is night and day, an engine is all about its seals; sealing is everything and the previous eras do not have the seals for the job.
Last edited by LLLosingit; 09-10-2016 at 02:25 AM.
09-10-2016, 02:30 AM
#15
Exactly what seals are you talking about here? Rings and valve seats haven't improved in decades and were actually better before unleaded fuel required hardened seats, Valves seals weren't an issue back then and neither were any of the external seals.
09-10-2016, 02:42 AM
#16
92-98 lol what was so special the LT engine? Still lame compared the 60's era performance wise, You obviously have no experience with pre emissions engines. 72-97 performance cars were a joke with very few exceptions. Most would get passed by anything on the road in the 60's with a V8 under the hood. You could get 100 octane at the pump and most engines built were at 10-1 compression or better and not just some of them...ALL of them. So they made plenty of power back in the day. 70's emission laws killed all the fun and it didn't get back to where it was until the late 90's early 2000's for some models.
09-10-2016, 03:12 AM
#17
Newer isn't always better or cheaper and until you figure that out people are going to keep calling you out on the bullshit you post. 
09-12-2016, 07:53 AM
#20
Sorry if what I have to say, you don't want to hear the truth. Even oil pan seals from 60-'s through 80's are garbage. Sorry about that, I didnt design it.
Also you can't stop me from posting, I don't know why you think this thread is 'yours' it is a place for opinions.
Old engines have old seal designs- simple as that. **** is a waste of time. Nobody wants to hurt your feelings not e'en me.
keep getting 10mpg not sure what you want to hear- EFI aint going to help much with that.
Also you can't stop me from posting, I don't know why you think this thread is 'yours' it is a place for opinions.
Old engines have old seal designs- simple as that. **** is a waste of time. Nobody wants to hurt your feelings not e'en me.
keep getting 10mpg not sure what you want to hear- EFI aint going to help much with that.