Gotta free LG4 from a friend. I have a possible deal on getting a TPI system. Will the 84 block accept the TPI manifold? Will the head bolts and such line up correctly?

I would like to rebuild the 305 with the TPI system and either drop it in my car or my dad's S-10.

Just curious as to what I may be getting into....headaches or a straight forward swap.

Im new to this.


thanks,
bill

 

Depends on what year the TPI system is out of. Anything before 87' and your good, anything after and the heads and intake bolt-holes won't match up. If you have an 87' and later TPI, you can use the L98 or LB9 heads and do alright with some porting.

 

The system is off of an 89 350.

So the holes wont line up on my stock LG4 (heads and intake)? What if I got some aftermarket heads. Would I be able to find a set that will match the tpi system and the LG4?

 

You'd need an 85-86 base. This will work just fine with the 1989 runners. I wouldn't drop money into heads for the LG4 just for the bolt pattern to match the later intake. Save that $ and go for a 350 later.

Swap won't be too bad. I assume the 2.5L is carbureted, which means you'll need to add wiring for the fuel pump, and adapt wiring under the dash. Get the whole fuel system from tank to engine bay from a TBI or TPI f-body since it's setup for high pressure, the sending unit will take the right fuel pump.

Matthew

 

so your saying that the 84 block wont work with the 87 and later TPI system. Okay, so I would need an 85 and up block?

84 block needs an 85 or 86 TPI to swap just right

or

get an 85+ block and the 87+ TPI will swap just right.





Oh, and my 2.5 is Fuel Injected. I couldn't image that motor being carburated on my heavy car!!

 

I said base, not block.

The TPI intake base from an 85 or 86 will bolt down to your heads. I much prefer to use the correct intake than to drill the center 4 holes of the intake; it can leak oil there.

So: 1985 or 1986 TPI intake base, your 1984 engine, and the rest of the 1989 parts.

 

The block will work perfectly, its the heads that are the problem. 87' and up heads have a different bolt pattern for the intake manifold than 86' and earlier heads. The blocks, up until the LT1, are going to work fine :lala:

You'll only need to do either of two things-

1. Get later model heads from a 87' and up V8.

or

2. Get a 85 or 86 model year intake manifold for your TPI (just the bottom part, the runners and plennum and everything are fine).

Then you'll have a nice running L69 :hail:

 

except for the compression ratio and some other parts. The LG4 is a nice torquey motor however, and the TPI will make it even nicer to drive than they are when carbureted.

 

Thank you for your patients. Im a dimwit sometimes when it comes to motors and such (id have to be to still have a 4 cyl right )

Your talking about the intake manifold right? Is there an aftermarket one out there...say edelbrock that you can fit the TPI runners and such onto? This way I can get a performance manifold and keep the same heads.....Or should I just search the junk yards and get a manifold from a stock unit?

 

Sure there is. I'd look at Accel, Edelbrock, and TPIS. Some of these may be setup for both bolt hole angles. However, the stock 85-86 base may be a better bet, economically, and should suffice nicely for the LG4.

 

Okay, so If I get the 89 TPI setup from him, I need to look into a different manifold and that should be about it? I mean just get a new base and start putting on all the rest?

Would a new cam be necessary? (to up the performance of the LG4) I know I want to get headers to open up the exhaust a bit.

I got the tranny, bellhousing, and other such things so Im getting closer to doing a decent swap. I was contemplating a turbo for the duke (just for show reasons) but this will be so much more economical.

Anyone know of a good place to get a flywheel for manual setups?


Oh, I guess I would have to change my fuel pump too. Its for the TBI duke. I guess I would need a larger unit.

This guy has the TPI setup, 305 injectors, ecm, and all the engine wiring. He didn't have the interior wiring(dash) and such.

 

You may want to re-cam it. I'd hinge that decision based on what differential gears are in your car.

The fuel system you have may work, just make sure it's 3/8" like stock on the pressure side. If it feeds to the drivers side frame area of the eng. bay, you may be good to go The pump, yes you need a different one.

The interior wiring isn't critical. Your stock ALDL should work but you'll want to jumper pin M to pin E since your ECM is capable of 8192 baud communication.

I have a 1985 Corvette flywheel that would work perfectly for you if you're interested.

 

My 84 has 3.73 gears in the back. I believe it feeds into the driver side of the bay too. I figured on the pump. My bro had a MPFI on his camaro and we put the TPI in..didn't have to change it.

How good is your flywheel and what are you willing to sell it for. Mind you im on a very tight budget.

I just got married less than a year ago and my wife and I bought a new house yada yada yada.

 

if you want, perhaps you should put some goodies in the LG4 first, LT1 motor cam, and port the heads. just suggestions, anything to squeeze more HP out of the engine is worth it!

 

I see no one has mentioned that you can also use the 87-91 vette base on the 86 and older heads. The vettes have the aluminum heads, which are the same bolt pattern as the pre 87 cast iron heads. You should be able to pick one up cheap on ebay.

 

Hmm. Not real familiar with the Vette base. Is the heat crossover for EGR present or is it only able to be done externally with that base?

 

Okay, Im working on a deal with this guy who has the tpi. here is what he is offering me:

the base, plenum, runners, ecm, most of the wiring, distributor, mas air flow sensor, and bolts ($350) Is this a fair price for what is being offered?

I got the LG4 for free but I need to rebuild it. I have the tranny and belhousing.

I need a flywheel for the clutch, going to buy a new clutch, new fuel pump and a few other odds and ends.


I spoke with this guy and he said it would probably be cheaper to get a used set of 87+up tpi heads and less of a hassle than the base itself. He recommended I opt for l98 aluminum heads. Would that work on my block?

Thanks guys again for your input and helping a fellow thirdgenner.

 

The aluminum L98 heads that came in the vettes have the pre 87 bolt pattern. That would put you back in the same boat you are in now. Just pick up a vette base on ebay for cheap and they will bolt to your heads.

 

You could always elongate the holes in the intake base to get it to line up. That is what we did on my TPI setup that I sold to a guy on here. I had both style bases, but he forgot to mention the year of heads he had, so we elongated the holes on the 87 Base and it bolted up fine to his 86 heads.

I did my first TPI swap 2 years ago, and it was a fun project.
If you have every part for the conversion, you can do a complete swap in 8 hours, and that includes drilling out the 4 center intake holes, that's how long it took to put my TPI onto the guy's car that bought it from me.

Here's a before shot of my engine,


And an after,


And here is a vid after the TPI swap and exhaust were put on,
http://www.transamws6.com/video/ZepherWS6.mpg

 

bills

I'm doin a TPI installation on my bone stock 82 trans am with the LG-4, added edelbrock headers, muffler eliminators, mine now has a 5 speed with 273 gears will let you know how much better it is

 

sounds cool I want to keep a 5 speed too.

I have an update. I may have an opportunity to get a complete 86-88 (can't remember the exact year) IROC with a 305 TPI. The motor on that car has a bad freeze plug so I would strip it down and transfer the heads, manifold tpi and such to my LG4 block.

I'll keep you all updated on that possibility.

Later,
bill

 

Is their any problem with the EGR setup on TPIs compared to LG4s?

 

They both use an ECM controlled EGR solenoid. Code 53 in the LG4 is about as troublesome as the code 34(?) in the LB9/L98.