4.3 TBI VS. 4.3 VORTEC

Factory engine information, modifcations etc...
Forum rules
Pictures should be posted in the Picture Post forum only. Links are permitted here. Posts containing pictures in this section are subject to deletion.
Red_Warhorse
30's
Posts: 63
Joined: Fri Apr 21, 2006 9:59 am

4.3 TBI VS. 4.3 VORTEC

Postby Red_Warhorse » Wed Sep 27, 2006 12:51 pm

I currently have a 4.3 TBI in my 91 Blazer.....it's got about 200k on it and it's time for a rebuild....while rebuilding I planned on getting headers, probably upgrading the TBI to the holley, edelbrock intake etc...BUT my sister has two 1994 Blazers.....both with the Vortec engine....both have good engines, but one is basicly a parts vehicle....she said I can have the Vortec out of the parts vehicle.....so I'm wondering would this be a direct swap, if so how much any of a pwer gain would I get by simply swapping motors.....and would the gain be significant if I added headers and K&N FIPK to the donor?!?
User avatar
Jamus
Staff Member
Posts: 5437
Joined: Wed Nov 07, 2001 3:55 pm
Location: Naoma, WV
Contact:

Postby Jamus » Wed Sep 27, 2006 1:12 pm

There's a thread on here where a guy used an 85 carbed 4,3 in a Vortec(CPI) application. So to run one of those engines you would just swap the external parts, intake and maybe sensors mostly. The vortec heads flow better, though not as well as the 96+ vortec heads. The 96+ heads have many more problems arice though, so you don't even need to worry about it. I say get the motor, go through it and freshen it up a bit and bolt it in. The CPI motor made 195hp, but it was mostly due to the fuel injection and not the heads. Though a better flowing head can't help but increase power. Add to that the age of your current engine, and the hop-up parts you plan to add and you should be happy with the seat of pants experiance once it's all done.
burntkat wrote:Well in that case, here's the truck I "haven't been building" all this time.... ;)
Red_Warhorse
30's
Posts: 63
Joined: Fri Apr 21, 2006 9:59 am

Postby Red_Warhorse » Wed Sep 27, 2006 1:32 pm

Sooooo.....it's a direct swap then?? I can just pull the old TBI and put in the Vortec(after new gaskets,headers, etc.)???
User avatar
Jamus
Staff Member
Posts: 5437
Joined: Wed Nov 07, 2001 3:55 pm
Location: Naoma, WV
Contact:

Postby Jamus » Wed Sep 27, 2006 1:40 pm

Pretty much. I can't say 100% that you won't run into any problems. Usually the problems will be small things like the senrors, brackets to bolt things to, or even different spark plug design due to the different heads. If the spark plug thing comes up, just get CPI plugs and gap them to TBI gap. You may not have a spark plug problem, but i did on my 2002 to TBI swap.
burntkat wrote:Well in that case, here's the truck I "haven't been building" all this time.... ;)
Red_Warhorse
30's
Posts: 63
Joined: Fri Apr 21, 2006 9:59 am

Postby Red_Warhorse » Wed Sep 27, 2006 1:47 pm

I was planning on pulling the old engine and replacing the whole thing with the Vortec......will those things(spark plugs, sensors etc,) still be a problem?/
User avatar
S15vortecpwr
31's
Posts: 187
Joined: Tue Apr 18, 2006 10:26 pm
Location: Wetumpka, Alabama

Postby S15vortecpwr » Thu Sep 28, 2006 11:46 am

I also remember reading a thread on here about a swap where he had to regap the plugs to get it to run right. If I remember correctly the gap was narrow than the vortec's gap and it would bog down in the upper RPM's.

Not to mention you may be (not sure) going from a flat tappet cam eng to a roller cam eng. That just means little more power and more RPM's. You may alos want to check on about a bigger cam since you have the eng out for more power. Just a thought....
94 S15 Sonoma 4x4 4.3cpi, 4l60E, TM lift, SL arms, zexel torsion 3.73, 31 yoko ATII

01 Trans AM WS6, Free mods, Diablo tune, at 19,800 miles why bother with it.
User avatar
93Jimmy4x4
31's
Posts: 102
Joined: Fri Apr 21, 2006 11:15 pm
Location: Florida
Contact:

Postby 93Jimmy4x4 » Thu Sep 28, 2006 9:28 pm

I had a TBI 4.3 and a CPI Vortec 4.3 and I would get the CPI Vortec 4.3 over the TBI any day of the week... Much better power and design IMO
1993 GMC Jimmy SLE 4x4- Rebuilt .30 Over 4.3 CPI V6, Flowmaster Exhaust, K&N Air Filter, SAS Soon & Possible V8 Swap... 1987 Monte Carlo SS- Drag Car... 1987 Buick Regal- Daily Driver
SurvivalistS10
205's
Posts: 19
Joined: Mon Oct 09, 2006 12:40 pm

Postby SurvivalistS10 » Tue Oct 24, 2006 10:27 pm

I have a cpi motor currently and it has been nothing but problems. I have heard others say the same. The cpi "spider" unit nearly always goes out...EXPENSIVE part. EGR valve, sensors, etc, etc. I hate it. I'm actually planning on going to a carb just to avoid it...
User avatar
S15vortecpwr
31's
Posts: 187
Joined: Tue Apr 18, 2006 10:26 pm
Location: Wetumpka, Alabama

Postby S15vortecpwr » Wed Oct 25, 2006 10:09 am

I have not a problem on my truck (knock on wood) from my CPI. It has roughly 130,000 miles and it is a 94 model. The SES light sis come once and it was the EGR. I performed a BG egr valve induction kit on my truck at about 95,000 and the light has not come back on yet.
94 S15 Sonoma 4x4 4.3cpi, 4l60E, TM lift, SL arms, zexel torsion 3.73, 31 yoko ATII



01 Trans AM WS6, Free mods, Diablo tune, at 19,800 miles why bother with it.

Return to “Engine”

Who is online

Users browsing this forum: No registered users and 1 guest