I have a 95 and want to drop in a 98 vortec. I still want to use the tbi set up. I know I can get the intake to do this, my question is:
* Will the 95 5.7 distributor work on the vortec 5.7? (don't know about the gear)
* will the 5.7 tbi be big enough to handle it?
*do i have to do anything to the chip in the ecm?
I see where people are changing putting vortec heads on the older engines but I can't where they have swapped the whole motor to tbi.
Thanks for any help.

 

mmmm, lets see if i can help


im not sure about to 95 dizzy workin on the 98, im pretty sure the L31s have a different gear, i would just stay with the 98

if your going to use the TPI, i would look into some 454 injectors, and a different intake manifold, one that flows better

the computer should be tuned yes

the L31s also use a different front timing cover. im not sure what the tach runs off of in the TPI but in the vortecs there a mag pick up in the timing cover. they make the covers with the hole for the mag pick up though if its not needed

 

Easiest way,

Get an edelbrock 4 barrel manifold tapped for vortec Heads.

Get a Throttle body adapter plate from Jegs.

Get an adjustable fuel regulator for your TBI unit to increase the fuel, they are lean from the factory.

You need a hardened distributor gear to use the TBI distributor with the Vortec Roller cam.

A custom chip will help, but not necessary. But i reccomend one .

DONE!

Now if you want better performance I reccomend calling SPR performance for a bigger set of injectors and all the other stuff you need.

 

I agree with Tim Z, while you can definitely buy a TBI to Vortec manifold, I would do like he suggested and just pick up a 4 barrel unit with an adapter. It will possibly leave you open for more options later and is usually cheaper to boot. You will need a melonized gear for the distributor for use with the factory roller cam, which you can pick up through the dealer. Like he also said, a custom chip is not necessary, but is recommended unless you change to larger injectors “AKA 454 throttle body”, then it is necessary.

Never the less, it is a very easy swap and will run so much better than the TBI 350. If you want to boost the output a little while your swapping motors, they are a little harder to come by now-a-days, but a good little upgrade used to be using a cam that was referred to as the '87 IROC-Z cam 202/206 .403/.415 115 (.430/.443 with 1.6 rockers) due to being a little larger than the truck cam and being dirt cheap. Almost everyone had one lying around, but we’re talking about parts that are 20 years old now. Another cam that can be had for almost nothing and is also a slight boost is the factory camshaft from a '95-'97 LT1 Vette or Camaro 201/208 .447/.459 115, you would need to check the timing dowel pin length in the front of the cam as they protrude a little further out (.030"), but you may be able to tap it in to the proper distance or cut it off slightly if it won’t tap in. The LT4 Hot Cam was drilled to where you could just tap in the pin, but it was designed so it could be used in various motors and the regular LT1 cam was really only designed for an LT1. I wouldn't spend much at all for either of these cams, as while they will be a decent boost, they are not enough to warrant spending much.

 

Thanks for your help. One more question, whar about the EGR?

 

With either the TBI to Vortec (part # 12496821) or even the 4 barrel intake from GM (part # 12496820) you can reconnect the EGR. Of course Edelbrock has the same equivalent manifolds available. To make the EGR function, you will need a driver’s side exhaust manifold from a 1996 or newer truck with an L31 Vortec 350 (part # 12557828) which is drilled and tapped to accept an EGR tube. EGR pipe (part # 10220275) can be used with EGR Valve (part # 17113457) and gasket (part # 12337972) to complete the system.

These manifolds are primarily intended for use of Vortec heads on 1995 and earlier (pre Vortec) engines, which have a thermostat bypass passage from the block directly to the water pump. When used as you plan to do, you will need to run a coolant bypass line from the manifold to the 5/8” hose nipple on the water pump (passenger side) if your block does not have the bypass hole, which it most likely does not. You would recognize it by the extra hole underneath the main passage on the passenger side of the water pump mounting area. Suggested routing is from the 3/8” NPSF boss on the manifold to the pump. Some people also get by, by drilling three to four 3/16” holes in the thermostat for the water to bypass through. If you do this it will work, but you will have to remember to always do this anytime you replace the thermostat or you will run into problems.

Good luck with your upgrade and enjoy!