85 305 TPI to 350 TPI

[dk05]

Anyone know what parts I would all need to do this swap? I will be re-using my TPI manifold and plenum, headers, flywheel, and all the accessories (alt, starter, etc..) I'm not going to re-use the damper though because I believe it would be smarter to replace it. What I am wondering about is more along the lines of electronics. I already know I need bigger injectors. Speaking of which... does anyone know of any injectors that I could use for the 350? They need to be 24lb or higher and decently priced.. all I can seem to find is Accel injectors, which I would not buy unless it was a last resort. Are there any sensors I need to change when I drop the 350 in? Also, is there a temperature sending unit for the dash gauge that fits in with headers? Thanks!

[ct91rs]

morley...

[dk05]

*bump*

[FormulaLT1]

305 and 350 are pretty much identical. Everything you had externally on your 305 should interchange to the 350 and also on a side note. I have some 24.9lb injectors from a LT1 corvette which had 39K that are interchangable with TPI's if interested but to be honest, unless your doing some modifaction a 19 or 22 lb injector will serve you just fine. 24lb injectors are really meant for 300 - 350 horse engines.

Also the temp sensor in the head should not interfere with the headers unless your working with some fabricated headers.

[FormulaLT1]

Also, your right. Accel injectors should not be a first choice. They are well known for leaking right out of the box.

[dk05]

Yeah, I am not too much of a fan of their injectors. I am planning on doing quite a bit to the motor before I put it in and also planning on 150-200 shot of Nitrous Oxide. Looking to get about 300-320 HP with the N/A engine though also. What do you need for the injectors? Also, do you happen to know the part number for the temp sending unit? Thanks!

[Morley]

You will need to change; Knock sensor (get one for a 350), injectors (need 22# but stay away from the Multec's), calpack for a 350.

[FormulaLT1]

I can't seem to find the parts number on www.gmpartsdirect.com to the coolant temp sensor located in the head but a simple call to your local dealer will most certainly get you that number,. As for your comment on what I need. Do you mean what do you need to make them work with your ecm or what do I want for them?

[dk05]

I mean what do you want for them money wise BTW thanks for the info Morley. I will probably have to custom tune the PROM though.

[FormulaLT1]

Shoot me a offer threw PM and I will respond with some pics of the injectors and if I accept the offer. I don't really like offering goods in open forum since I don't allow members to make threads of classified items . I also think I have a knock sensor for a 350 but have to verify its part number if interested. I can also get you a pic of that.

John

[wrightz28]

Originally Posted by FormulaLT1

I can't seem to find the parts number on www.gmpartsdirect.com to the coolant temp sensor located in the head

Because there isn't one on a '85. Only the gauge sending unit between cyls 1 & 3. The actual temp sensor is on the front of the intake manifold.

[FormulaLT1]

lol , ah that would explain it. Thanks

[wrightz28]

No prob, drove me nuts too, and I own one.

[dk05]

wrightz28:
Do you happen to know the part # on that sending unit? Thanks.

[wrightz28]

SU109 for the wells through autozone. This same was used on alot of Gm's of the day, even my 87 Buick 3.8 uses the same one.

i put it in both cars, the Buick is fine, however I'm still having irregular fan op in the Z28, which oculd be the hack job on the wiring. But you may want to check out Chevy or TPI PARTS (link avail on TGO). I only say that becaseu the 85 ECM seems very twitchy to some generic stuff.