I'm going to be installing a new engine in my 1991 Suburban in February/March. Depending on weather cooperation. Truck currently has 350 tbi, 700r4/241c. This thread is to help me keep my thoughts organized and input/help/suggestions from you guys. Im not interested in a ls swap. My plan right now (subject to change) is this long block. http://paceperformance.com/i-648492...00-chevy-gmc-full-size-trucks-3-4-ton-up.html. GMPP intake. http://paceperformance.com/i-6255261-12496821-cpp-vortec-tbi-intake-manifold-with-egr.html. Water pump. http://paceperformance.com/i-625171...-l31-5-7l-vin-code-m-or-r-vortec-engines.html. Probably the Tbi chip and fuel pump kit from Tbichips. Not sure about the Holley TBI. I've read some bad things about those. Ive got a little more research to do on that. I want to run exhaust manifolds, not headers. It seems that 1987 g3500 manifolds are stainless steel and supposedly really good flow. Dorman makes replacements 674-530 and 674-531. Any insight or info or anything from guys that have done this is greatly appreciated. I'm sorry for bringing up this dead dog topic, but I'd like to have some idea of what I'm getting into before the parts start flying. Thanks
CK5
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Engine swap 1991 suburban
- Thread starter Rmy660r
- Start date
Not usually in this forum, may forget to check back in, but that intake is pricey. I assume you don't have emissions concerns? If that is the case, a carbed Vortec intake with TBI adapter plate is probably going to run you $200?
You don't need a special water pump. I believe GM started using those because they had heater valve shutoffs (although the big blocks had them forever IIRC). Whatever reason they used bypasses, if you don't have a heater shutoff valve (apparently some of these trucks did) you don't need a bypass. I'm running Vortec heads/TPI Vortec intake (10+ years) and I don't use another bypass.
TBIchips is somewhat iffy. Team208motorsports here will do tuning, I'd suggest going that route over TBIchips.
I'd stay away from aftermarket parts as much as possible...it increases cost and decreases availability. And you are right, the aftermarket has a spotty record when it comes to injection stuff. I think they've gotten better in general, but still not OEM reliability IMO. The TBI unit is not likely to be a restriction, and if it is, you can go with a BBC unit if more flow is needed.
GM made and catalogged stainless manifolds for a variety of years, those may be what you list. The link in my signature will take you to a listing of manuals and parts catalogs, I know for a fact my 1985-1988 GM C/K/R/V parts manual lists the stainless manifolds, and last I looked them up, they were still available through GM. IIRC they weren't SUPER expensive, not as much as most GM parts often end up being.
You don't need a special water pump. I believe GM started using those because they had heater valve shutoffs (although the big blocks had them forever IIRC). Whatever reason they used bypasses, if you don't have a heater shutoff valve (apparently some of these trucks did) you don't need a bypass. I'm running Vortec heads/TPI Vortec intake (10+ years) and I don't use another bypass.
TBIchips is somewhat iffy. Team208motorsports here will do tuning, I'd suggest going that route over TBIchips.
I'd stay away from aftermarket parts as much as possible...it increases cost and decreases availability. And you are right, the aftermarket has a spotty record when it comes to injection stuff. I think they've gotten better in general, but still not OEM reliability IMO. The TBI unit is not likely to be a restriction, and if it is, you can go with a BBC unit if more flow is needed.
GM made and catalogged stainless manifolds for a variety of years, those may be what you list. The link in my signature will take you to a listing of manuals and parts catalogs, I know for a fact my 1985-1988 GM C/K/R/V parts manual lists the stainless manifolds, and last I looked them up, they were still available through GM. IIRC they weren't SUPER expensive, not as much as most GM parts often end up being.
Thanks for the info. I'm going to try to stay oem as much as possible. I don't have to worry about emissions where I live. I know its pricey, but I like the idea of the intake made specifically for this swap. I am fortunate in that I live about 15 miles from Pace Performance and about 35 miles from Summit Racing. Those exhaust manifolds are the stainless steel tube style. Those are at the top of the list unless I discover something better. Is the big block throttle body a direct fit or does it require an adapter? Thanks again for the help
BBC throttle body needs the TPS repinned, it's easy to do if you find a donor.
If you don't mind the price of the intake, no reason to avoid it. Only bad thing about the Vortec heads is the limitation in regards to cost effective EFI intakes. I'm not partial to adapters, but if I were on a budget I'd save that money for other components.
But that block comes pretty well equipped already.
If you don't mind the price of the intake, no reason to avoid it. Only bad thing about the Vortec heads is the limitation in regards to cost effective EFI intakes. I'm not partial to adapters, but if I were on a budget I'd save that money for other components.
But that block comes pretty well equipped already.
I've not read anything bad at all regarding tbi adapters, but I've budgeted for the GM intake. I work for GM and can usually get 10-15 percent off on parts at the dealer. I read an article about changing the pin after you mentioned the big block throttle body.
I'm pretty sure that is the long block I'm going with, unless there is a better choice I haven't found. I'm not trying to build a powerhouse, just a little more power. Reliability is my main goal. Im planning on new alternator, starter, sensors etc. about the only thing I'll be using from old engine are the serpentine belt brackets.
This is my first time swapping engines, so I'm researching everything to death. The fewer surprises, the better.
I'm pretty sure that is the long block I'm going with, unless there is a better choice I haven't found. I'm not trying to build a powerhouse, just a little more power. Reliability is my main goal. Im planning on new alternator, starter, sensors etc. about the only thing I'll be using from old engine are the serpentine belt brackets.
This is my first time swapping engines, so I'm researching everything to death. The fewer surprises, the better.
Since you are looking for longevity and just a bit more power, that engine should do well for you. Really don't think you can go wrong. The only reasons the Vortecs suck are casting thickness, goofy intake requirement, and the valve springs/lift issues. But again, for a mild performance increase vs. all out power build, they are a good choice. Otherwise you'd be into a short block and then add aftermarket heads, etc., and that gets time consuming matching up all the parts, etc.
For the cost of those stainless GM manifolds, you can probably get Hedman Stainless Headers, they run $6-650. Now the tubular manifolds may be better at making power than stock manifolds, but the stock manifolds vs. headers is usually a 25HP difference on a small block, and that's obviously significant. Not saying do it, there are reasons not to go with headers, it's just a fair bit of power to put on the table, especially if considering the hassle of going with non-stock manifolds that are going to require exhaust work anyway. Just some thoughts on that. I used to be totally anti-header, but for the power increase, it's hard to say no.
For the cost of those stainless GM manifolds, you can probably get Hedman Stainless Headers, they run $6-650. Now the tubular manifolds may be better at making power than stock manifolds, but the stock manifolds vs. headers is usually a 25HP difference on a small block, and that's obviously significant. Not saying do it, there are reasons not to go with headers, it's just a fair bit of power to put on the table, especially if considering the hassle of going with non-stock manifolds that are going to require exhaust work anyway. Just some thoughts on that. I used to be totally anti-header, but for the power increase, it's hard to say no.
I would definitely like the extra hp of headers over manifolds. I'm having a difficult time finding headers that people are completely satisfied with. It seems like a ton of reviews and comments are about leaking and rusting and being too close to plugs/wires. It seems like manifolds are problem free and durable at the expense of hp. Being a 6500lb high center of gravity rolling brick, I should probably leave that 25 hp locked up.
Oh, that's right, you are big block. The small blocks have a hands down winner from Hedman, but I would think any of their stainless versions would be the same. The flanges are extremely thick, the metal seems to be as well.
Never been a fan of coatings, I prefer the stainless. Expensive, but there is no coating to ever wear off. One problem is the O2 bung, you'll have to have it welded in. But perhaps buy a set from someone that will let you return them if they don't fit, check fit, if they are good, have the O2 bung welded in, and be done with it.
IMO almost all problems that are blamed on headers (outside of rotting out), are from poor installation elsewhere. Yes, thin flanges will probably not help matters, but the headers really shouldn't be supporting any weight. Most people (and many shops it seems) use flimsy mounts for the pipes/muffler, and all that weight acts as leverage on the headers...the flanges, the collector, and the metal itself. With properly supported exhaust (another reason to go single) the only movement the headers have to deal with is the engine moving in it's mounts, and the frame flexing. I've got poly motor mounts and paid attention to how I secured my exhaust pipes/muffler this time, and the header connection has held up fine.
Never been a fan of coatings, I prefer the stainless. Expensive, but there is no coating to ever wear off. One problem is the O2 bung, you'll have to have it welded in. But perhaps buy a set from someone that will let you return them if they don't fit, check fit, if they are good, have the O2 bung welded in, and be done with it.
IMO almost all problems that are blamed on headers (outside of rotting out), are from poor installation elsewhere. Yes, thin flanges will probably not help matters, but the headers really shouldn't be supporting any weight. Most people (and many shops it seems) use flimsy mounts for the pipes/muffler, and all that weight acts as leverage on the headers...the flanges, the collector, and the metal itself. With properly supported exhaust (another reason to go single) the only movement the headers have to deal with is the engine moving in it's mounts, and the frame flexing. I've got poly motor mounts and paid attention to how I secured my exhaust pipes/muffler this time, and the header connection has held up fine.
I have used Thorley Tri-Y headers on three of my square bodies with small blocks and they all fit great, did not leak and had good plug clearance. I um using 90 degree ceramic boots on my current set up since I run the wires under the headers along the block, zero issues.
Well.... My timeline just got sped up. I've got an oil pan full of antifreeze. Checked the oil and radiator Sunday afternoon and discovered the mess. Gonna be too cold this weekend to pull engine. Hopefully better weather the following weekend. Summit Racing has most everything in stock that I want.
L31-r long block
GMPP Vortec/Tbi intake
JBA stainless shorty headers
Im open to suggestions for quality starter and alternator.
I'm leaning towards a rebuilt/ modified Tbi unit from spr/tbichips. They have a 46mm built for my specific combo
All new sensors. Gonna get oe stuff if I can find it
Maybe new motor mounts since they're gonna easily accessible.
No egr/emission worries
What else am I missing???
Any suggestions will help
L31-r long block
GMPP Vortec/Tbi intake
JBA stainless shorty headers
Im open to suggestions for quality starter and alternator.
I'm leaning towards a rebuilt/ modified Tbi unit from spr/tbichips. They have a 46mm built for my specific combo
All new sensors. Gonna get oe stuff if I can find it
Maybe new motor mounts since they're gonna easily accessible.
No egr/emission worries
What else am I missing???
Any suggestions will help
The distributor gear is "melonized" GM part# 19052845
Thanks for the heads up. I found a Chevrolet Performance distributor that has the melonized gear on it.
I may be changing up my fuel injection ideas. Pace Performance sells a kit made by FiTech. I talked to a guy at their shop and a guy at Pace about the system. I may give it a shot. It'll need a bigger fuel pump that I was gonna do anyway and I can use a much cheaper 4 barrel Vortec intake instead of the GMPP piece. It also has a few new sensors preinstalled. It should end up be a little cheaper than what I was going to do. Here's a link and I'd appreciate any thoughts/feedback positive/negative about trying this system.
http://fitechefi.com/default.asp.pg-GoEFISystem4-InjectorKit
http://fitechefi.com/default.asp.pg-GoEFISystem4-InjectorKit
You could keep it fairly stock (but hugely improved) by using the DynamicEFI computer upgrade.
Basically uses ALL the stock GM sensors, parts, and replacement parts. The computer is updated, so other than a little tuning, you are good to go and replacements are easy and everywhere. Adds nice little things like electric fan control, EGR removal, AIR removal, all through some easy software.
http://www.dynamicefi.com/
Even allows you to basically maintain or improve your fuel system as you want, but not needed.
Basically uses ALL the stock GM sensors, parts, and replacement parts. The computer is updated, so other than a little tuning, you are good to go and replacements are easy and everywhere. Adds nice little things like electric fan control, EGR removal, AIR removal, all through some easy software.
http://www.dynamicefi.com/
Even allows you to basically maintain or improve your fuel system as you want, but not needed.
