S-10 Forum banner

41 - 58 of 58 Posts

·
Registered
Joined
·
68 Posts
I have a build thread. But havent been able to work on this much. Need a day off... 6-7 days a week 10 hours a day. Lol no time for anything but next couple of weeks I am going to get some stuff done to it
 

·
overthinker extraordinar
Joined
·
650 Posts
Hey Max,
I have been studying the numbers on the motors that you posted. I have a questions. I noticed the differences between the carbureted and TBI motors was the compression, the size of the valves, and the valve lift. Could a person put an intake manifold and carb on a TBI motor? I cannot see why you couldn't. Secondly, could the heads(the larger valve size) be used on the older carbed engines? Would that also increase performance a bit?

And then with that thought, I was wondering what the heads of the 3.4 would do on a 2.8 motor? I have a line on a set of 3.4 heads for free, just need rebuilding.
 

·
Registered
Joined
·
2,134 Posts
The iron heads are the same from 1986 to the end of production. That includes the heads on the 2.8, 3.1 and 3.4, all the same. So 3.4 heads will show no improvement over using 2.8 heads.

Also the above heads are the same for all intents and purposes as the earlier "HO" heads that were commonly found on the 2.8 in the Citation X11.

The external physical dimensions are the same for the entire run of the iron heads, so yes you can swap intakes.
 

·
Boozebag
Joined
·
9,021 Posts
Discussion Starter #45
I blew the dust off of this thread so maybe you 2.8 /3.1 /3.4 guys can learn a little about these engines.
Maybe it will become a sticky (?)
 

·
Registered
Joined
·
49 Posts
at what size of cam does running 1.6 roller rockers require additional work to the heads?

can stock 2.8 TBI ECU handle : 4.3 tbi unit with 4.3 injectors, comp 260H cam, 1.6 rockers?

assuming bored/ported intake and heads, and headers.


building a hot rod via S10 chassis ... trying really hard to atleast drive it once or twice before going back to 2.5 years of solid college in sept. haha ... all the bits will be swapped to a 3.4 with better care to the internals, and probably a turbo and proper tuning.

just wanna know if the 2.8 unit can handle it resonably well until then
 

·
Boozebag
Joined
·
9,021 Posts
Discussion Starter #47
can stock 2.8 TBI ECU handle : 4.3 tbi unit with 4.3 injectors, comp 260H cam, 1.6 rockers? assuming bored/ported intake and heads, and headers.

If you do the 4.3 TBI, as you know, you will need to open the intake under the TBI. The 2.8 ECU will run it, but you will want to add an adjustable fuel pressure reggy.
Headers are good, but you will need to add a bigger exhaust system behind them.

Roller rockers are expensive. If you add 1.6 ratio, you will be adding a little lift to the cam specs. The comp 260 H is a pretty mild cam, although it is a TON better than the stocker. As you probably know, you'll need new lifters too, and will need to run "break in" oil for the new cam. It has ZDDP in it which is a high pressure additive.
https://en.wikipedia.org/wiki/Zinc_dithiophosphate


You can run a pretty large cam with 1.6 rockers. The Voodoo truck has a .500 lift cam with 292 duration. I HAD to run roller rockers. I was driving back from NY State and a rocker stud snapped.
Crane rockers come with ARP screw in studs. I haven't had any more problems.
 

·
Registered
Joined
·
49 Posts
yeah theres a lot there I'm aware of ;) (quick background ... injury retired Tech/fabricator ... currently an auto parts counter jockey while going back to college for mech engineering :D )

so at work I can get crane, comp, arp , hedman etc etc ... so while not cheap, prices are nicer looking at stuff like arp kits, roller rockers

is your Voodoo truck posted on here? realistically anything more then 250-300 hp in this particular build will be wasted ... I really want to stay with the 60 degree v6 simply to keep down the weight up front, and keep it farther back too ... theres basically no drag racing around here... minimal autoX ... so building more towards corner carving then just going fast staight line

the hot rod i'm doing is still using the s10 firewall/front floor and amenities
 

·
Registered
Joined
·
49 Posts
I've later realized that the begining of my reply above may have been 'dickish', and was not intended to be :(

while I do have alot of experience with engines, etc and custom work I have never nor will I ever claim to know everything. I'm on this site because I've had little to no experience with the 60deg v6

kinda trying to pick some of my parts in the thinking of switching to the 3.4 later... and/or addition of turbo (I may do initial testing etc of turbo on the 2.8, ya know... grenade the 2.8 not the 3.4 LOL )


In that regards ... I'm guessing a 260 grind would be better to focus on? it wouldn't give full gains in the initial (although still a drastic improvement over stock cam ) .. but should be better suited for a turbo later

looking at doing the 454 TBI too (with 4.3 injectors.. tweak with fuel pressure) .. again it wouldn't show any real gains on the N/A 2.8 .. maybe some throttle response .. bit of a headache to tweak in for the n/a .. but would definately help for a turbo later. (basically like down jetting a carb that's too big for an engine )


is there any decent threads or sites...etc for opening up/porting the tbi intake manifold and heads? I haven't touched a set of heads in years .. and even then the last set was just a clean up they barely even needed a port match ..

ofcourse my next journey will be into the Eprom tuning and that I have no idea how to make a run at :(
 

·
Registered
Joined
·
49 Posts
okay ... the TBI swap thing .... there is SOOOO much conflicting information out there

4.3 tbi on the 2.8 ... which freaking injectors ? just as many people say the 4.3 injectors the ecm can't compensate for and you have to switch to 2.8 injectors ... as the 4.3 injectors are fine

melling MTC5 cam (think staggered 260 cam)
1.6 ratio stamped rockers
early sbc (302/z28) spring
DIY port matched and opened up intake and heads
headers
elec fan
AIR and egr deletes
possibly underdrive pulleys if I can get my hands on em
bump the static timing

I'll be doing a few of the small 'tbi' unit mods ... smoothing the top ridges, lifting the injectors... and running a completely custom built aircleaner housing with a 'bowl' type feed to the tbi unit via an neat oval edelbrock aircleaner

(I'll be attempting to make it look like hillborn/ITB outside covering the tbi but that has nothing to do with performance)

4.3 injectors? ... 5.0 injectors? ... or just FPR with the 2.8s? the 2.8 rebuild is a compromise of OEM cross parts that are close enough to the big name bits and also makes my rebuild cost like 1/3rd canadian then the prices I was looking at (ie crane cam/rockers/springs ...etc) If I like the project once it's 'streetable' a hybrid 3.4/3500 will replace it etc
 

·
Boozebag
Joined
·
9,021 Posts
Discussion Starter #51
Bump for sticky and info
 

·
Boozebag
Joined
·
9,021 Posts
Discussion Starter #54
^^^ A lot of guys use the Dodge Intrepid fan assembly. It seems to work very well.
Most of the aftermarket (Chinese) fans couldn't blow out a candle.
I have used several... :tdown

A Ford Taurus fan also blows like a tornado...
 

·
Awww..you ain't got shit!
Joined
·
3,295 Posts
I have a Cavalier V6 in mine. Works well, fits easy with small mods to shroud. Single fan. I've never had working AC but will have it fixed next year so we will see how it fares. Used to have a write up on it...well I do, but thanks to PHOTOFUKIT we no longer can see the pictures.
 

·
Premium Member
Joined
·
2,027 Posts
2000ish Ford Contour fans as well. They fit the radiator like a glove and blow hard as hell! They have one of the thinnest profiles of these OE fans. As was stated above most aftermarket fans suck balls!
 

·
Registered
Joined
·
637 Posts
I sold my Offenhauser / 390 Holley to someone on this forum years ago, before I switched to a 3.4 with TBI. Is that it I see in those pictures...brings tears to my eyes,lol. I read a lot of negativity about the 2.8. I had the early 2.8 in an 83 blazer and in over 20 yrs. it was the most reliable and trouble free vehicle I have ever own.
 
41 - 58 of 58 Posts
Top