Hey guys. New to this site. I have been out of the car stuff for a while and am jumping back in. My last fun car was a 70 Nova ss 396. Wish I still had that!. Anyways, I have an 86 IROC that I bough fresh outta high school. It has the 305 tpi with a 700r4. Its getting a knock, so I want to do a build over the winter. Question is: Where do I start? Holy cow..LT, LS, CRATE, ECT...I would like to grab 4 to 500 hp and nice torque numbers. Which engine is the easiest to swap? wiring harnesses? I have a Vortec from a 99 silverado available tranny included for $600. Its the 327. Any help would be welcome. Thanx. Joe

 

There are a number of "stickies" at the top of this forum and the LSx/LTx sub forum that will provide a tremendous amount of information that will help guide you in the right direction with regard to what to swap.

Based on the horsepower numbers you're after, I'd lean right toward an LS swap. Costs will be about the same regardless of platform at that horsepower level (assuming all new components), but the LS will make that power the most gracefully. It'll have better table manners and better fuel economy. The drawback is that the LS will be more complicated to swap in, but to be honest, at the horsepower level you want, even sticking with the SBC is going to require some pretty extensive upgrades, both to the motor & drivetrain itself, but also to the fuel delivery & engine control... the same stuff you have to mess with for an LS swap.

 

Thanx kid. Your pic looks just like mine sans the scoop. I was even considering charging the motor to help with the hp increase. Yeah I see everybody gets rid of the optispark system for whatever reason. I already have subframe connectors welded in. Know I will have to build the tranny reguardless of the one I go with. Its not going to be a daily driver, so fuel economy is not really an issue. I just want to be able to kick my brothers *** on the track. He has a 71 Duster running 11.90s. Keeps bustin my *****. You know the story. Friendly family feude. So I will probably have to address the k member issue and the wiring. Painless can help out there I imagine, unless I acquire the harness and gas pedal from donor car. Is there a year/car combo suggestion I should look for? Thanx again

 

Optisparks are on the LT1 motors, and most of them are very unreliable, which is why they are disliked.

LS motors don't all have drive by wire. Most of the older ones had cable driven throttle bodies, and the newer ones can be adapted to use one. Painless and others offer stand alone harnesses, but you still need to integrate parts of your existing harness. Most of us start with the stock ls harness and integrate it.