Maybe my car isn't stock. Meybe the owner before me put a stock 350 tbi motor in it. What they are rated at like 210 hp and i don't know like 280 torque. So with the mods to a 350 like that... what do you guys think that would put me at... Those 350 i think came with center bolt valve covers i think also, so the only way for me to tell would be to look at the casting numbers. Right?

 

*** you guys are bad you never know if that car was modified before. The guy is happy leave him alone. I too once had a GTA except it had a done 355 with everything. Lots of torque, but it would need a hundred horse hit to keep up to my ws6. Still killed a few mustangs and this wacko who thought he had a 400 horse vega. Maybe he just couldn't drive. A third gen would need a big block to keep up with me now. Hey the GTA was fun it shifted into second with the tires smoking just right.

 

Honestly I don't think it would matter much. The TBI unit is such a huge restriction that no matter what you put under it, power just does not happen. I've seen so many attempts to make this induction system make power and go fast over the years, and everyone ends up with mediocre results at best, with endless amounts of frustration. What's the Thirdgen.org record for N/A TBI at? high 13s?

And while MrDude_1 may act like an ***, he is right on TBI [lack of] performance. However, him listing the dual snorkel air cleaner (as opposed to the single snorkel) as not being a performance mod, well... Back to back dyno runs on my Z28 showed over a 20rwhp difference.

 

ALL SBCs after like 87-88 come with center bolt heads. Check the Casting #s.

 

I agree with you Marcz28
But the only thing is, I don't think 305 302eater ever meant this to be a thread about whether TBI is a good induction system. IT ISN'T. I don't think anyone will say it is. It IS however, basic and reliable because it emulates a carb.

Family has had a lot of TBI chevy trucks and they have given us zero issues. Torquey, but like you said, not going to be staying on top of a motor you want over 300HP from.


But it is more than capable of supporting high 14s. TPI being the other option for the year was far more powerful, and in my experience, the most problematic injection I ever owned. Great power till you hit the runner wall of 4500 rpms, but my GTA, which was a blast, stopped being able to manage its own fuel and all sorts of bugs. 89,000 Original Miles, but too many years.

However, as I've said before, with that car running at its peak, I could not pull away from his 92 RS.

 

Just to add fuel to the fire, I'll throw in my experiences. I had a 86 IROC w/ the 305 TPI w/ a mild cam, ported TPI stuff, headers, gutted cat, catback, 2000 rpm stall TC, 3.42s, etc, etc and it was pretty good for a 305. The cam made a huge difference but was noticeable that it had one.

I had my brother run the IROC against my bone dead stock 94Z LT1 A4 w/ 3.23s (complete w/ paper air filter) and the LT1 put a solid 3-4 car lengths on the IROC despite me spinning more out of the hole. He got a car out of the hole since I was spinning but I just flat ripped him a new one through every gear after that (stopped as I was just into 3rd, not even a full 1/4 mile). With some bolt ons like I have now on the LT1 (headers, catback, CAI, ECM tune) it would be quite embarrasing for the 305 IROC.


I look forward to the dyno sheet for this TBI, but I will be surprised if it is over 190 rwhp. I have to say I don't believe for a second the car pulled on a LT1 that was racing or running at all close to properly. If this 305 had some internal mods that would put it power wise at bolt on LT1 levels it would be noticeable. No one would be mistaking it for a stock 305 TBI (one of the tamest boat anchor motors around). And even with a decent cam and slight head porting it is not going to make over 240-250hp w/ the stock TBI intake and assorted junk choking it.

My money is on the 4thgen in question being a 3.8l V6 w/ exhaust... That I could see. I worked over a fair number of those in my old IROC. I really just don't see it happening otherwise, but stranger things have probably happened... For the posters sake I hope I am wrong, I know how it is to be stuck with a less than ideal setup and having no funds to change it. I limped around with a coiuple other stockish 305 TPI thirdgens for years wanting more...

None of this should be construed as thirdgen hate either, I still love them and will probably get another someday to build up again. Great platform IMO. My 87 Z28 that I put a decent 350 in w/ Vortec heads, decent cam, and the assorted supporting mods would have eaten my LT1s lunch with total ease (I pulled on several stockish LS1 cars w/ that 87Z, strong runner)...

 

Well said. We need numbers to continue this...I can however vouch that this was a true LT1. I almost went to look at it because it was for sale online, six speed with slp loudmouth. V8. The only laser blue repaint on 18s, 2 inch drop, in our small area, the peninsula of Washington State.

 

Well I think the fact that it's a 6spd tells the story... not everbody can drive

 

Very True.

 

Dont meant to hijack but I couldn't help but to ask. Myth has it 3rd gens handle better thatn the 4th gens. Any basis to this myth? (I'm talking IROC vs. Firehawk, B4C, SS, WS6 etc...)

 

I'm sure someone on here owns both. My GTA with WS6 has a very good rating for skid and I believe what is called auto cross use popularity.

Them being lighter might be the whole stem of this myth. Not nearly the technological level of an ls1 suspension, just less weight and more balanced.Ls1s are noticeably bulkier. 305 302 Eater has a complete iroc suspension, a rarer optioned one with wonderbar and all, and the car is amazingly tight and firm, but I have never driven an ls1 with the ws6, so someone please give their opinion.

 

I do. And I won't go any further than that. I've done so before and everyone around here gets upset

Camaro Fan = Ray 86IROC?

 

Ahaha.

I can only imagine.

I guess if you were attention hungry it would make a great thread. Impressive third gen by the way.

 

Believe me I know cars and this was no 3.8 V6... I have raced other lt1 cars and not won all but they cant pull more than a car on me. These have all been from roles. When I go to race them from a stop they puss out... I don't know if its cause my car is insainly loud or what. Once i get above 3000k I could be mistaken for a built 350. I am very loud. But like everyone is saying my car should be slower than most rice but for some reason its not. And i will never claim TBI to be for performance. If i wanted performance and i had a 350 i would have stuck a carb on it already. But i don't see the purpose of doing that to my 305 since i will be swaping moters soon anyways... But as i said i will get numbers for all you guys, I'm just waiting for my friend to get enough money for his T56 swap in his IROC for me to do. Then we go.

 

I had a 91 Firebird with the 305 TBI. It was very reliable for the 5 years I had it but very slow. I added headers, exhaust, K&n open element filter, chip, 3.42's and it wasn't even close to my 1997 Trans am. It was decent from 0-50 then it ran out of steam quickly and on the highway forget about it. Must have been a bad driver.

 

Yeah I don't post over here very much, I'm sure I will when I snag an LS1 car sometime soon hopefully. I need a nice LS1 SS to replace my 94 Z...

I don't know about the handling, my thirdgens and my 94Z seem pretty comparable handling wise. I don't do any serious racing where I'd have numbers to truly tell. The brakes seem significantly better on my the 94, but that could just be the ABS throwing me.

 

I want to see a slip for that.
My 95 Z28 A4 went 13.89 @ 99 when it was stock 3 years ago, just had a K&N filter and new Goodyear GTII 245's.

If you can run high 13's, low 14's it wont surprise me youve taken out a couple.
Even if youre car had a SB 350, it would still need some things to match the LT1's Fuel Injection.

Like headers, a big *** holley carb, maybe head work and a cam.
And after all this time, you still don't know if you own a 350 or 305?
Do you not know how to tell?
I know a way you can. The 1320.
Go get the white ticket.

Exactly.

 

well imo the 3rd gens handle better.. but i havnt really pushed the limits with my 4th gen yet, i love it too much lol but my 3rd seemed more stable in the corners..atleast until i hit a bump but thats just my opinion im no autocrosser, just a hell raiser
btw well said camaro fan!

 

To Burnzilla, Don't know if you saw it earlier or not,

But he has a previous "White Slip" from before any of his bolt ons for 15.3 seconds in the 1/4. No cat. Auto. etc.

An updated one is what we need now.

 

Actually I still had a cat and everything. Felt slow as hell compared to know.