Hello! I am new to the TPI game and just recently came into an 89 IROC 350. I can't decide if I want to go with a ProCharger, or go all motor and have the one that is in there now stroked to 383. Please, help me decide. Thanks!

 

All personal preference my friend. Do what ever puts a smile on your face

 

You could have a good ammount of power compared to the N/A 383 while running pump gas; better MPG.

 

Procharge it.

 

The less moving parts, the less likelihood of problems. As long as you are not shooting for big power, I'd go with a 383. You can tell people it is a 305 and they will never know. This is coming from a guy who has had Paxton cars, nitrous cars, SBC cars and a stroked BBC car. For a daily driver/weekend toy, I would go with the 383 every time. My 1990 with a 350 was running deep into the 11's on pump gas with very little effort and full weight (full interior with stereo but no AC) through the 700R4 and stock rear.

 

What is your goal for the car?

Street car?
Track car?
Daily driver?
Car shows?

My Formula is supercharged, big engine, and is fast as crap. But it's somewhat obnoxious to drive. The tires break loose constantly, it's loud, it has a nasty idle. The 3 speed automatic and higher stall converter mean the cruise RPM's are higher than they should be, it gets about 6mpg. At wide open throttle under boost it will burn almost a gallon a minute.

My vette on the other hand is quiet, smooth, and very enjoyable - but 1/2 the power.

You need to determine what you want to do with the car before you throw money at it. It's easy to get lost in a build.

-- Joe

 

Once you go boost, you never go back.

You'll make a lot more power in the vast majority of cases with a blower motor ... that's why people build blower motors.

That being said the only possible drawback is fitment, complexity and potential to really grenade some **** if something goes wrong.

My 2 cents, build a 383 with the thought of boosting it down the road and start slow, build some experience.

Set yourself up with some good heads and a cam to match (the cam you can always change later), and go with low compression (9.5:1 at the most) then you can easily add a little boost to it later without much more than a cam swap.

The best advice anyone can give you is to look down the road (figuratively) and always be playing to long game. Don't paint yourself into a corner with a high compression motor that makes MAX possible power naturally aspirated if your end-game is to someday add a blower/turbo to it.

My motor is a little on the ridiculous side, but it still made well over 500hp without the blower on it, so you could have a ****-ton of fun with it even n/a. That will also give you time to get the rest of the parts in the car up to the task of handling all the power you'll make with forced air, while you're still having fun with it.

 

You have the same heads as me but less cubes. What cam are you running?

I'm curious how you pulled off 500hp with low enough compression to run that huge head unit.

Still enjoying the west coast? You should see what they did to the exit 46 rotary.

-- Joe

 

Bro, my mom bitches about the rotary every day. I'm coming home for christmas in a few weeks and I'm terrified. The West is the best dude, except for the price tag :/ How are you?

It's a custom comp blower grind. 262/272 @ .050, and at the time it was .640/.640 lift. It's about 8.5:1 compression. All we did was put it on the dyno and throw the handle. We didn't even tune it to run N/A, we just put the 950HP blow-through carb on it and let it rip as-is. I think it was running at about 9 or 10:1 air/fuel haha ... it made 518 hp like that, and we revved it to 8,200 RPM (It peaked around 6,000 though).

I'm in the process of installing Jesel shaft rockers right now (Finally), as two of my comp pro mags chipped their nose rollers and ****ed up a couple valves. These are 1.6 ratio, so I'll be at .700 lift on both sides now ... should pick up some power, because that's what it needed, right? Lol.

 

I'm doing well, thanks. I spent a few years in LA back in the early '90s. It was warm, but the people all had epic attitudes.

The rotary is crazy. Probably even worse now since it snowed and you can't see any of the markings in the 6 lanes.

That's interesting. That's a lot of duration.. Must have a nasty idle huh?

I'm running 224/236 @ .050". Fairly mild I guess.

.700 eh? Yikes. I get nervous with huge lifts like that.

-- Joe

 

Glad to hear it man! I'm in Santa Cruz, which is pretty close to SF and only about 30min from San Jose, so it's not that warm here haha ... but it's not that cold either. It's much better than SoCal people-wise though.

The idle isn't bad at all really, because it's a blower grind the overlap is low ... I think it's on a 114deg lobe separation. That being said, it's not ultra-snappy down low obviously ... at least relatively speaking. This thing is finally going to realize it's RPM potential which is exciting.

Theres plenty of room for that much lift with the dished pistons, and it has springs to keep the valves out of the way, too. They're 240lbs on the seat, and 570lbs open.