Well I am deployed right now and my wife is buying me a 1986 Light Blue IROC-Z with the TBI 305 & 700R4. The car is completely stock right now & I just want to do a few things to help wake it up.

I am thinking of adding a UDP & Amp pulley, adding an Electric water pump, Hooker 2055s & a Hooker catback to start with. About how much rwhp could I expect to get out of the little LO3 with this?

Right now I Daily Drive my 06 GTO that has a heads/cam/ Maggied LS2 & made 590rwhp and 545 rwtq @ 8PSI. I just got a 102MM snout, 102 TB, Carbon Fiber Powerchamber intake & Meziere EWP for it!! Anyways its getting to be a bit much for the wife to drive so we will be sharing the IROC alot. Thanks for all your help, John

 

is the date wrong on the car 86? tbi was not offered in 86. are you sure it is not tpi? or did someone do a swap.

 

It might be a carbed car... It is not a TPI car though.

 

'86 non-TPI will be carb-most likely LG4 as very few L69"h.o."were made for '86.In addition to the exhaust upgrade you have planned,cam upgrade should be done too as original LG4 cam very,very mild.Underdrive pulleys and electric water pump will certainly add a little high-RPM horsepower,but probably not enough to notice and likely not worth the possible negative effects and hassle(reduced low-rpm charging and coolant flow ETC.)Electric water pumps are usually not recommended for vehicles that see highway use,but some on here have reported the electric pumps they used did ok for highway use.

 

Thanks for the info, I know in the LT1 & LS1 world that Meziere pumps are rock solid. And they have awesome customer service if any problems do come up. I think adding a new Alternator would be a good idea when doing the pump install. My friend Kent picked up about 2-3 MPGs on the highway in his 99 T/A when he installed his SLP UDP & used Meziere EWP. Plus it did pull a good bit harder afterwards.

 

Throw 3.42's in, 25-2800 stall, and a shift kit/Corvette servo,bump the timing with full exhaust and open element or better yet a cool air intake.

 

The 3.42s are exactly the gears I was thinking of using, my friend Jesse said the 3.73s would be to short with the 700R4. How can I change the timing on the LG4? I have to use HPtuners to change anything on my GTO & that was a nice $600 that I spent...

 

You'll like the 3.42's in a low hp 305 like the LG4. It makes the car a lot more fun to drive and won't kill your fuel economy on the hwy.

To change the timing, hook up a timing light and turn the distributor. Pretty simple really.

 

If it does have a carb I say exhaust, gears, stall converter, mild cam, new intake such as a edelbrock performer or performer rpm(the rpm might have hood clearance issues I'm not sure) and a 600cfm edelbrock or a holley with vac secondaries. Oh and in that order because then everything will compliment each other. underdrive pulleys are a waste of money in my opinion, theres alot better things you can do to the car with a 100 bucks or so also do not go big with the cam being a 305 a healthy cam for a 350 is a wild cam in a 305