CAM vs RPM vs GEARS

[WH1 85]

Alright let me say this. I love my car and my engine. Easily the funnest and fastest car I have ever owned. Wouldn't trade it for anything. Well maybe a GNX. But I'm still waiting for that offer.

BUT, my engine takes a dump after 4,900 rpm. From my understanding almost all tr's max out around this range. ( Or am I mistaken?)

Question is, is our cam/valvetrain the culprit. If not, then what. It couldn't be our ignition?

Is this why no one puts steeper gears out back? 3.42's is good. But I like the feeling of 3.73's or 3.90's. I'm used to small block chevy's that you can wind up to 6,000 and still be in the powerband. And this was with 350 tranny's. We have overdrive. So we should be able to go with steeper gears and still get good gas mileage, (On the highway at least )

It makes since that an engine that only rev's to 5,000 will limit it's top speed with steeper gears. But if you could get the rpm's up to say 6,000-6500, this would more than compensate. Plus you would lauch ALOT harder.

Am I crazy, is something wrong with my car or is there some basic
mechanical knowledge of these cars that i am missing?

Or is there a way, (valvetrain/ignition?), to get another 1,000 rpms out of my car.

Any insight beyond, "if you want a 350 then buy camaro", would be GREATLY appreciated.

 

[crazygn]

Try being me bad side of both worlds, i have the turbo 350 in my gn, and can only hit around 4800-5200. Mine seems to pull hard from 3400-4200 then kinda dies off tho. I guess the only thing to help it rev would be a bigger cam, and i have a 206.

When you find a way to rev that thing please let me know.

 

[WH1 85]

Sorry but I had another thought. (This question will also show my basic ignorance, so bear with me).

What are the gears in our tranny's? My firebird has a 700r4. I like the splits in my 200r4 better. First feels lower. Am I correct? Both are stock with basic shift kits. Could our tranny gearing contribute to my rearend question?

This all originates from debating with a friend about rear gears for his car. He's slammin a 350/350 into an 84' cutlass. After we finally got his trunk open, (only took us about 2 hours). Don't ask why, it's an even longer story. But after looking up the rpo codes we found out it had 2.14's

Well after he stopped looking angry, we started trying to figure out what gears he should swap in. This caused me to question why we don't use steeper gears.

 

[crazygn]

man i dont know how that car would move with those gears , not sure about the 700 but the 350 is geared lowerin first so it takes off a little slower. 3.42's just work nice in these cars , and i'll tell you i dont think my old set up would have moved with 3.73's all i would do is spin with the 3.42s. I dont know if i would go any bigger then 3.73's with the 200r4 but might work nice.

 

[TType84]

off the top of my head, the numbers that come to mind are

2.74 1.65 1.00 .067

 

[Buick From Hell]

In the old days on this board, one of the "standard" answers to the "why won't my engine go past XXXX rpm??" question was another question:

"how old are your valve springs?"

 

[crazygn]

i remember that , myself i have new springs, i think the car hates me tho.

 

[6SENSE]

Wow, another serious hotair guy in St. Louis!? (Or does it have an intercooler?)
I have known of a couple of guys in the area with hotair WH1s over the years, one of them ditched the motor for a 305 (!!??), that leaves one... do I know you WH1 85?

Justin

 

[WH1 85]

Hey whats up 6sense. No I do not know you. Nor do I know ANYONE with a TR. I've be going it solo. I hardly ever see any t-types or gn's around town.

It's cool that you got a Hot-Air to. And no mines doesn't have cooler. AND IT NEVER WILL. I plan to get an intercooled one someday,(86' Rosewood T-Type). But I'll always keep this one.

What part of town you in. I stay by 270 and 70. I been wanting to see another hotair. For comparison, my car feels plenty strong to me. But I have nothing to judge it aginst.

Hit me up sometime. I'd like to check out the car.

 

[cool 84]

4,900 seems about right for a stock motor. Even with fresh valvesprings mine fell on it's face at that rpm until I moved up in turbo size. Even a bigger cam didn't make that much difference but for some reason the turbo made it really breathe at higher rpms. The reason we don't change gears is the torque. These things are torque monsters and most will slow down with 373s, especially a stock motor car with stock size tires. Mine pulls to 5,500 now but I very rarely take it to that rpm because I want to keep it reliable.

 

[6SENSE]

WH1 85,
Im surprised you havent seen many TRs in the area, believe it or not we have a pretty large Buick/TR community here, with some very noteable people in the Buick world.
My brothers and I are part of the local GSCA. Coincidentaly we are having a meeting this Sunday, you definately should come and check it out. Email me at j62king@hotmail.com for details. Im in U.City, by 170 and Forest Park Parkway.

Justin

P.S. Although I know of alot of TRs around here, there are very few hotair cars and noone I know that is serious about them. In fact I am the only hotair guy in our local GSCA (hence the "lone hotair") and I have never seen anyone besides myself racing a hotair car at Gateway! Plenty of 86-87s though.

 

[turbowrenchhead]

That rpm sounds right. Mine did the same thing. I swap the cam and springs. I put in a 204-224 and it didn't improve much. The stock turbo just cant feed it enough. I thing the TE-64 will solve that problem. Just hope I can fit the wastegate in.
Fried of mine has an 87 with a stage motor and M&A heads and all the goodies. His is setup to shift at 6000 rpm and he has 3:73 gears but runs larger tires at the track. Its redlines right at the end. His motor pulls really hard all the way through. But he has a TE-64-1 and a liquor i/c.

 

[TType84]

a liquor ic huh?