'85 FJ60 with 5.7/350 TBI - so weak (1 Viewer)

Joined
Jun 22, 2020
Messages
17
Location
Houston
Hello all.

I've got a '85 that had a 5.7/350 TB iinstalled in it in the late 80's. As far as I can gather, it's using the original transmission with the addition of a manual overdrive. For all intents, everything from the tank (replaced on an 80's recall just weeks ago) to the TBI has been replaced. The ignition system was also made fully up to snuff. But man, I tell you what, this has got to be the most anemic car I've ever driven. You can floor it and feel like you're going nowhere. I'm not sure where to go with this, but am on the verge of selling the thing, as the driving experience is just plain frustrating. I've looked at every forum out there.....anyone have any clues/pointers at all?

Thanks a ton for reading,
Mark
 

OSS

Joined
Jun 30, 2017
Messages
3,319
Location
Oblivion
Sell it. Any tips you might get on this forum aren't going to suddenly transform it into a powerful fun to drive vehicle.
 

NCFJ

Supporting Vendor
Joined
Jan 22, 2007
Messages
9,296
Location
Chesnee, SC
OP, the cause for your anemic experience with a 350 TBI can be one of quite a wide array of issues. It can be anything from fuel delivery issues to a clutch that is slipping, poor spark, low compression, restricted air flow etc etc. You are talking about a twenty year old swap, perhaps it was a lack luster engine to begin with, many 350s from that era were far from stellar performers and not much better, if at all better, than the stock motor that came in the truck.

Keep in mind that in that time period 1 HP per 1 cubic inch was considered high performance and it took a whole lot of performance parts to get there. Now that same HP to CI ratio is normal across the board. I would suggest you seek out someone that knows his/her way around the motor you have and find out if it is indeed up to par, at least. Like I stated before, SMCs from that era were nothing special to begin with as they were all wrapped up in trying to meet government standards for pollution. This led to a great many slugs out there on the highway.

I don't know your budget or your expectations, but if you are looking for something with some ummmppphh to it, you may find yourself looking into Gen 3 or 4 GM V8s. Give us more information when you get it, perhaps something will show itself as the problem with your set up. good luck!
 
Joined
Jun 22, 2020
Messages
17
Location
Houston
Sell it. Any tips you might get on this forum aren't going to suddenly transform it into a powerful fun to drive vehicle.
I was rushed when I ended my post - I should've simply asked if anyone knows of a place in Houston that knows TBI's in and out.
 
Joined
Jun 22, 2020
Messages
17
Location
Houston
OP, the cause for your anemic experience with a 350 TBI can be one of quite a wide array of issues. It can be anything from fuel delivery issues to a clutch that is slipping, poor spark, low compression, restricted air flow etc etc. You are talking about a twenty year old swap, perhaps it was a lack luster engine to begin with, many 350s from that era were far from stellar performers and not much better, if at all better, than the stock motor that came in the truck.

Keep in mind that in that time period 1 HP per 1 cubic inch was considered high performance and it took a whole lot of performance parts to get there. Now that same HP to CI ratio is normal across the board. I would suggest you seek out someone that knows his/her way around the motor you have and find out if it is indeed up to par, at least. Like I stated before, SMCs from that era were nothing special to begin with as they were all wrapped up in trying to meet government standards for pollution. This led to a great many slugs out there on the highway.

I don't know your budget or your expectations, but if you are looking for something with some ummmppphh to it, you may find yourself looking into Gen 3 or 4 GM V8s. Give us more information when you get it, perhaps something will show itself as the problem with your set up. good luck!
I really appreciate this response! I fully understand that my expectations may be entirely unrealistic. I've owned some older cars over the years: '65 Thunderbird, '66 Mustang, '67 Porsche 912, '68 Mercedes-Benz 280 S, '72 Super Beetle... None of them felt this sluggish, The car just feels as though something's holding it back, like it's running on 4 cylinders instead of 8. I fully appreciate that this is a 200 HP motor (when new - who knows what it's outputting now) trying to move a 4300 lb vehicle, but there's absolutely zero pep when rowing through the gears. I suppose if I could have someone drive it and, definitively, tell me "This is exactly how this should perform." them I could either live with it or move on (I would move on).

As I replied above, I really should've simply asked if anyone knows of a TBI specialist in Houston.

Again, though, thanks for the thoughtful response, NCFJ.
 
Joined
Jun 22, 2020
Messages
17
Location
Houston
OP, the cause for your anemic experience with a 350 TBI can be one of quite a wide array of issues. It can be anything from fuel delivery issues to a clutch that is slipping, poor spark, low compression, restricted air flow etc etc. You are talking about a twenty year old swap, perhaps it was a lack luster engine to begin with, many 350s from that era were far from stellar performers and not much better, if at all better, than the stock motor that came in the truck.

Keep in mind that in that time period 1 HP per 1 cubic inch was considered high performance and it took a whole lot of performance parts to get there. Now that same HP to CI ratio is normal across the board. I would suggest you seek out someone that knows his/her way around the motor you have and find out if it is indeed up to par, at least. Like I stated before, SMCs from that era were nothing special to begin with as they were all wrapped up in trying to meet government standards for pollution. This led to a great many slugs out there on the highway.

I don't know your budget or your expectations, but if you are looking for something with some ummmppphh to it, you may find yourself looking into Gen 3 or 4 GM V8s. Give us more information when you get it, perhaps something will show itself as the problem with your set up. good luck!
Let me add the following: The motor idles smooth and nice at 600 RPM. It cruises quite well at 65/70 (but can pin the speedo if necessary - 90/100+?). However, acceleration feels labored and, as I said, anemic; it takes a lot of effort to get up to speed.
 
Joined
Jun 22, 2020
Messages
17
Location
Houston
I bet a set of heads would wake that thing up... assuming everything else is in working order. I think the TBI heads are notoriously crappy
Yep. That's exactly what I'm thinking. It spent months at Javier's in Houston, reworking the fuel delivery and cooling systems, but I still feel it's just not right as far as acceleration goes...and it just may flat-out be that it never will be. But here's a question for you guys: How responsive are your 4.2's? I mean, if I feel this 5.7 V8 is sluggish, by comparison your straight 6's have to take a full 30/40 seconds to get to cruising speed.
 

cruisermatt

Un-manufacturable
Supporting Vendor
SILVER Star
Joined
Jul 22, 2012
Messages
9,749
Location
Orlando Florida
Ok, I've driven a few 350tbi 60's, when working right, they're no rocket, but still substantially more powerful then the 2F. How's the compression? Maybe it's just worn out.
 
Joined
Jan 17, 2005
Messages
5,619
Location
Southern Colorado
Do you have cats and could the be plugged or could you have any other exhaust restriction? That might explain why it runs well enough but acceleration is poor.
 

Users who are viewing this thread

Top Bottom