Things you might not know about newer Jimmy's(Turbo Project)

[UR50SLO]

Fall is here and winter will be here soon. We are putting the Typhoon up for the winter so I can re-paint it along with several other improvements!

Anyway.. the point of this thread. ....... ....

Heahter's previous truck is a 98 GMC Jimmy. We were going to sell it since we had the Typhoon but after alot of low ball offers we decided to keep it. Then I had the Hair ball idea to use all of Heahter's old Typhoon parts on the 98 Truck.

I got a used set of Typhoon manifolds off a board memeber here (thanks again) and today I started the conversion.

I've only spent about 4hrs on it and already have the manifolds on and downpipe on. I scabed a Intercooler off a guy here that got it from e-bay. Nothing special but maby it'll drop the inlet temps a few degrees.
The Typhoon Exhaust manifolds fit right on! Same on the stock Typhoon Down pipe!
I had to cut one tab off the pass. side accry. bracket but that was it!!!!! I had to move a ton of CRAP out of the way .. wires.. ect. I'll make my own front of the wheel well and drop the battery down 6" or so.
This looks like a prity streight forward retrofit!!!!
I'll be using EFI Live for tuening to the stock 98 ECM.
I've got the Pillar mounted Wideband and Boost gauge already done!

Hope everything go's this easy!~
I'll post some pictures tomorrow as I hopefully wrap up most of it!
2days for a turbo setup ain't bad!!!
Especialy as most of the old parts were just sitting collecting dust!
Laters,
Scott~!

[SYO237]

and i just bought a 98 chevy blazer..... hmmm.....

[1BADSUV]

Are you going to keep it completely stock on the outside? I still want to build an Oldsmobile Bravada with a Sy transplant.

[UR50SLO]

This is not a good picture but give you a idea what it looks like.


I plan on leaving it close to that.

Like to get another set of rims that look nice but that'll come later.

Put the cowl hood on it a long time ago.

We'll see how the plastic intake and newer injector system likes boost Lol.

I think 6-10psi would be plenty fun. I'm wondering if this setup might suprise us with

good results?

Results are only a few days away, (Crosses fingers)
Scott~

[sy#2921]

Fuel system is your enemy. Those damn poppet valves are only 19lb/hr's. You will need to get a 10:1 rising rate regulator and bump the fuel about 2-3psi for every pound of boost if you actually want a hope in fueling the turbo. A wideband and in cab fuel pressure gauge and inline pump/walbro are a must in that application.
I have been there and wished I never did on an 01 s10 and a procharger. Even with all the tuning in the world you still need to mess with the afpr in severe weather changes cause it will change the afr's a point or more.
If you got any other questions reguarding what I did send me a pm

[UR50SLO]

19lb/hr fun.. . I won't use a FMU. I steer everyone away from those. If I could adapt my Holley Manifold to the Vortec heads I'd do that! Or is there a way?

I wonder what size injectors/poppets they use on big blocks? I could swap in one of those.

I'd like to run bigger than 19's in it for sure. Homework time!!!!!
If you've got any other info for me that'd be great!
Thanks!
Scott~

[hatrik8]

I'm an idiot. Everytime I looked at the title of this thread, I was like "Who the heck is newer Jimmy?! And what don't I know about his place?" I should get more sleep or maybe read the thread.

[sy#2921]

The fullsize vortec trucks pre ls based motor suffer the same problem. To the best of my knowledge after searching for years there is no other production part that can be swap due to the nature of the poppets and the "spider" system.

Your best bet is to put a carb intake and get some real fuel injectors on that motor if you dont want to use an FMU as a bandaid. Only downside is you have to hack the harness up a little to make pigtails for the individual fuel injectors. There is a way around this by going to a junkyard and getting a spider out of a truck and destroying it to make a female harness connector for a fuel injector harness

[UR50SLO]

Hatrick8 Lol...

I have a Holley (carb style) intake and a precision upper plenum. But it's for the Non Vortech heads.

Unless there are adaptors or someone who can machiene this intake to fit?

There is a mariene manifold for the 4.3's that is MPI. I'd have to find a used one since this is a

"beater" and might be only driven in the winters. I think I should be alright with under 10psi with

The stock setup. If I was planning on gonig any harder I know I'd need more.

When I boosted my 89 Maxima I was at 6psi stock everything with 181,000mi. No tune Factory

everything. It made it alot more fun to drive. That's all I'm after at this point.

I played with a Vortech SC on a TBI truck several years ago. I hated every part of it. Never ran right.

Always lean or rich.. fuel leaks yuck. I feel your pain there!

Thanks for the tips!
Scott~

[UR50SLO]

Just a progress report:

I needed to drop the front axel/diff out to remove the oil pan. I decided to replace the timing chain and timing cover while I was at it. At 140,000 on the Odo. .It was time.

The return line went in the pan with out problems.. the bottom of the engine looks great.

I had to shave alot more off the stud on the drivers side power steering mount to get the manifold to seat correctly. But all that behind me now.

I started it up and ran all the new coolant/oil through everything till it got to temp. No leaks so far and it's a little quieter than it was N/A.

All I have left is the intercooler piping and I'm done. I'd post pic's but you guys tend to get scared when I show you things all cut up and not finished

It'll be a couple more days before I'm done with that and get to test drive it.

When I get to that point I'll post some pictures
~Scott

[GMPartsGuy]

I have to agree with sy#2921, those poppet valves are capable of little more than what a stock engine can do. However, there may be an alternative........

Few people know that GM has a "real" injector setup available as a replacement for those stupid poppet valves, but only for small blocks. The injectors fit in the same place as the stock poppets, and wires go from the injectors up to where the original injector (the electrical portion) resided. Now, I have never seen one of these updated setups, because they're quite expensive. Whenever we have a customer that needs some injectors, we usually give them the option of updating the injection system because they've been down that road before. They usually end up having a stroke, and opt to go with the original style injectors.

If you're interested, I could see what kind of screamin' deal I could get ya. Maybe it could be modified to fit a 4.3 relatively easily. I would think that small block injectors would be better than those stock poppets.

[UR50SLO]

I replaced the injector setup in a 1500 series with a 4.3 at the begining of the summer. I got it from the dealer and it was setup just like you said. Instead of having the injectors in the middle and poppet valves it had lines that go to a small injector with wires right at the port. I doubt they are any bigger than the stock poppet valves but I'm sure that they are alot better at not failing and spray pattern.
I plan on getting a little test time/drive time and changing the injectors before I tune. I think the injector and the adaptor bracket with gaskets was 180.00 area. The new connector/injector sit's different than the stock one and requires a adaptor bracket.
I still think the Marine intake manifold would be the best choice. That'll have to be another day's project.
Thanks for the suggestions and input... I'm down to the last intercooler pipe to the throttle body.
Almost there~!
~Scott

[sy#2921]

I have seen guys go to that setup with mini injectors right at the port but they are just as small as the stock setup. You are right about them being more durable though.

[Raist103]

i want some pics

[91blazins10]

Originally Posted by Raist103

i want some pics

x2