I may have an opportunity to purchase an 87 IROC with a 305 TPI and auto tranny.

Its a LB9 305 TPI. Is this worth looking into? I mean can I add some things too it to increase power? If so what types of things? I thought headers and a good exhaust.

Im looking to drop the drivetrain into my Firebird if all goes well. I may pass on the opportunity if the motor is bad or not. (I haven't spoken to the owner of the car yet).

Could I take off the intake and such and mate it up to a 350 block?

Just curious if this would be worth the time.

 

There is a huge aftermarket for performance parts for SBC's, 305 and 350. Anyways, headers and a good exhaust will certainly wake up a 305. Swap the cam, port and polish, its all a matter of how much time and money you want to spend.

Just curious, why would you want to drop the drivetrain into the firebird?

 

The iroc im looking at is in sad shape. The rear end is damaged and the interior is trashed. I was looking at it for the motor only. It would spend more money restoring that car than I would building up the engine and dropping it into my Firebird. I don't know the details on the car just yet but I have been keeping my eyes peeled for a good 8 holer to drop into my firebird someday......If Im going to take out the 2.5L IRON DUKE. I want it to be a great motor to replace it.

 

well, the 87 would be a roller block. This is a good thing. The 305 auto's in 87 got the "peanut" cam. A cam swap and full exhaust would make it a very good running car. TPI's respond very well to exhaust upgrades.

I ran 14.6 in my 87' 305TPI 5-speed IROC with just a cat-back and an AFPR. SEE SIG. NOTE: 5-speed 305TPI's had a better cam 25HP advantage. Stock LT1 cams work well in 305's and are dirt cheap. It wouldn't be a total terror on the streets but for the small amount of dollars it could take to do it I bet you could get 13's out of it with a very streetable tranny/gear set-up.

Hodge

 

yes you can run good #'s with an 87 LB9. check my sig.

 

If you do all the bolt on stuff

Cold Air Intake
Headers
Gutted Cat or Hi-Flow Cat
Catback Exhaust
Air Foil for Throttle Body
Ported Upper Plenum
Aftermarket Runners
Ported Base Manifold or Aftermarket Manifold
Upgrade Ignition of course

If you do replace the peanut cam, consensus says you must hehe, I'd say an optomistic shot at high 13's is very very achievable with all the stuff that goes without saying like good tires, good state of tune etc.

Good luck - what a step up from the 2.5 lol.

 

WOW, New87...those are some good#'s for your 305
i got a 305 in mine and with the mods I have I only ran 15.4...I think that sux cause you said you ran 15.4 STOCK.........So if I was to add headers, a cam....I should be in the low 14's? I had it dyno'ed and got 184 and 264 torque....

 

Yes replace that cam! It was the best move I ever made. I went from a 15.4 to a 14.6 with the cam and porting the intake. As a matter of fact the LT1 cam that is in my car may be up for free to who every wants it in the next few weeks.

 

I'll take it New87....keep me in mind when you get rid of it...

 

Thanks everyone for the info. It sounds as if this would be a sufficient type of motor for my Firebird.

I want to keep the 5 speed. I drove an 84 Z with a carbed 305 w/5speed once. Pretty peppy. I think a TPI 305 with some mods and a 5 speed would be a blast to drive. Plus I love driving a stick anyway.

Here's the deal. Would I have to replace the clutch disc and pressure plate to mate up with the 305? If so what should I go with? I know I'll have to replace the Hydrolic slave cylinder too wont I? I just replaced it about a year ago. So I have a brand new one in there. I don't think it would be strong enough to push a stronger pressure plate. Would my 5 speed on my 4 banger work with this motor?


HODGE,
what is a roller block?

I talked with the guy that was "storing" the car for his friend and he said he did put some new rocker arms on it...rollers I think.....is that what your talking about?

Im really anxious to talk to the owner of the car to find out whats going on with it. I lost the number so I will have to drive buy the place again and get it. Too bad its 2.5 hours away from me!!!

 

I ran a 14.68 with only ET Street's and 4.10 gears. The car came already with a FM40 and some head and intake work done to it. Since then I have upgraded the iginition system to MSD and have put Edelbrock headers on the car.

Next week the Torque Converter will go in plus the Edelbrock Intake Mani plus runners.

I hope to get a 13 out of this setup before I put the blower on it in Feburary.

 

i agree thats why i am looking for a 90 - 92 tpi 5 speed thirdgen

 

Roller block means that the lifters have wheels (rollers) on the ends of them. This allows for a more aggresive ramp on the cam. Another advantage is that the lobes on the cam don't wear out because the "wheels" just roll across the lobe. Lastly, you can reuse roller lifters on a new cam becasue they don't wear down like flat lifters do. This saves money.

It is also why the LT1 cam will slide right in without changing anything else. (although a set of valve springs would be a good idea I don't think that they are required to swap in a LT1 cam.

Hodge

 

i did a pretty nice build on my 87 305 tpi 5 speed,

mods in sig, ill get times soon as i can

also have recently added
1.6 roller rockers to get more lift out of the lt1 cam

as for your clutch, u would probably want to pick up an s-10 conversion clutch disc, summit carries them for 2.5 and 2.8 s10 v8 swaps , i beleive they are $$expensive though also because of the gearing of your t-5 i wouldnt expect it to last too long, but now u can upgrade to a t-56

u will also need a v8 t-5 bellhousing, im not 100% on the hydrualics but u may ne able to use your stuff.

roller blocks are the 87-later, usually with centerbolt heads, but not all of them,


as for if its worth it to do, i would say that with a setup like what i have u will definitely enjoy it and not be dissapointed, especially compared to whats in there now.

if u have any other questions shoot me an email or Pm me or something

later
Matt