TPI86TA

So with the old stock engine being replaced with a new engine with a mild cam, I need some advice on what stall speed torque converter. I have a 700R4 transmission. I was leaning towards a 2400 stall but dont want anything overkill. Here's the new engine set up:

355 small block
TRW forged pistons
Comp XE268 cam
Vortec Heads
Crane Gold Roller Rockers 1.6
Edelbrock RPM airgap intake
Cloyes double roller timing set
010 2bolt main high nickel block
Holley Sniper EFI
Hooker Super Competition Shorty Headers 1 5/8", 3" out

Pro Built Automatics

The camshaft you chose here (224-230-110LSA) is way to big for the torque converter stall and diameter you want (12" @2,400 rpm stall). You will need a 9.5" diameter lockup torque converter with a 2,800 rpm stall - 3,200 rpm stall to make this work. Otherwise go to a smaller camshaft.

TPI86TA

Wow man, no kidding, see that's why I ask..I have no idea on this stuff. I definitely want to stick with this cam. I heard guys running this car with a stock converter but I dont know how that could even work. I appreciate all the advice

TPI86TA

fasteddi

iTrader: (2)

I ran the xe268 cam in my 385 last year and it did very well. Fun to drive around and it was quite fast at the track. I had a freakshow 3500 9.5 inch stall converter. 325 bucks iirc. Something around 3000 would work well with that cam. I also had 3.23 years at the time. Now I have a carb, and it's a race car set up but I managed 15mpg on average on the streets. I have a th350 so that didnt help me.

if I was you and wanted that cam I would get a 3000 stall and also a external trans cooler.

TPI86TA

thanks fasteddi. Yeah I'm realizing an external trans cooler sounds like a must. The more I search the web, the more this sounds like the range stall I want. Its crazy though some of the things I've read at other sites about guys run the same cam and set up

TPI86TA

So do I want a stall converter or a lock up converter, and what's the difference?

SirReveller

iTrader: (4)

I went deep on this a little while ago:
https://www.thirdgen.org/forums/tran...selection.html

You’ll want lock-up almost certainly unless you never go on the highway.

Orr89RocZ

iTrader: (20)

You can make 2400 work but i agree 2800 is lowest i’d go. Do not fear the stall!

And yes lock up is required for highway use if you want efficiency and lower trans temps

86LG4Bird

iTrader: (1)

What's the intended use for the car?
If it will always have street tires on it and just the occasional trip to the strip for ***** n grins, a 9.5" 2800 stall will be nice.
If you'll put DR's or slicks on it and want a good 60'/ET at the strip, then I'd go with a 3600, making sure it's a "tight"/efficient brand such as a Yank SS3600.
Don't waste your time and money on any 12" converter when looking for anything over 2200-2400 stall.

TPI86TA

Yes exactly, street tires with the occasional trip to the track. So 3000 lock up converter sounds like a happy medium

TPI86TA

Are the summit racing brand torque converters any good? I'm now torn between that one which is a 10" or the one from FTI Performance which is a 9.5"

TPI86TA

Should I still be running a converter lock up kit so I have overdrive since I'm ripping out the fuel injection? Stall converter doesn't change that right?

86LG4Bird

iTrader: (1)

OK, so now we have it really narrowed down Definitely no more than a "typical brand 3000" for street tires.
You're now at the point where the brand you choose will have more influence on its true stall and driveability characteristics than whether you choose a "2800" or "3000" advertised stall. eg., If it's a Vigilante or a Street Edge, I'd go with a 2800; if it's something with a high STR and "tight-driving" like a Yank SS series, you could even go with a SS3200. In normal driving, people will typically mistake the SS3200 for about a 2800 stall converter.

86LG4Bird

iTrader: (1)

Summit brand is a crapshoot. As I alluded in the post above, a "3000" from them really doesn't tell you how it's going to drive. I have no experience with FTI, so I also can't tell you how that one would drive.

86LG4Bird

iTrader: (1)

That's correct, you still want lockup for street/road driving.

SirReveller

iTrader: (4)

Grab a Circle D through Dana along with a street/strip shift kit. He improves on the TransGo kits and includes the infamous vette servo. Don’t have to drop the tranny either.

Top of the line TC and firm up your trans to enjoy it. One-stop shopping.

Just my two pfennigs after exhaustively running through all the makes and options...

Pro Built Automatics

I carry the Edge and Circle D. For this I would use the Edge. FTI is very good too.

Orr89RocZ

iTrader: (20)

I second edge. Had 3 of them and all been very good

86LG4Bird

iTrader: (1)

Very good experience here with both 2800 and 3000 stall versions of the Street Edge (9.5")

Jorlain

iTrader: (4)

Is it really that bad? Comp Cams only recommends 1800+ stall.

86LG4Bird

iTrader: (1)

That's because Comp wants to sell camshafts to EVERYONE, even those who fail to understand the need to upgrade complementary parts to realize the performance gain. It's simply marketing.

Orr89RocZ

iTrader: (20)

I dont think its that bad. I mean with a good tune it will drive fine on stock converter. Had a much bigger cam than that on stock converter before. Only problem is it wants to idle higher than stock so its against the converter abit harder than stock so it will want to drive on its own while in gear. Meaning you take foot off brake in gear and car will take off lol. So you gotta be careful

Also between idle and roughly 3000 rpm it will be abit lazy. If you ever drove a stockish ls1 car with stock converter and 2.73 gears you would know how this feels. Turd off line til 3000 rpm or so. Thats why most go 2600-3200 for most street cars with mild mods to cam builds. Its great starting point for most and good compromise

At the race track a 3600-4500 might be the absolute best for 60 ft and et but its alittle softer on the street.

Jorlain

iTrader: (4)

I guess what I meant to say was, that there's really more to it than just your stall. You would want a higher stall if you're running 2.70 gears, obviously. But If you're running a 700R4 and 3.73:1 rear gears, you already have so much multiplication that a lower stall speed converter will have less impact and it'll also run cooler on the street since there'd be less slippage.

But it all depends on what your purpose for the car is and how deep your pockets are.

86LG4Bird

iTrader: (1)

~3000 stall and 2.70'ish gears would get you the numbers at the strip, but would drive like crap on the street.
Complementing a higher stall converter with steeper gears, you won't get that "soggy" feeling taking off at mild/part-throttle.
Stock stall and steep gearing feels great on the street with a mild cam, but leaves a lot on the table for 60' times at the strip.

Orr89RocZ

iTrader: (20)

My ls1 car with 3200 was fine on street with 2.73’s. In fact i went 3.73’s and no other changes and only gained .06 in 60 foot and barely .1 up top. Street driving didnt feel any different except where the downshifts would occur when goin wot. Wasnt worth the money on that setup but to be fair i am sure shift point adjustment may have helped with gear but it would have helped with 2.73 as well

The kicker was i lost 4 mpg highway

86LG4Bird

iTrader: (1)

Yep, gearing gets you very little at the strip compared to the TC upgrade. Part throttle "feel" doesn't matter there!
Stock cam LS1? Must've been a very mild one if it felt fine with a 3200 and 2.73's.

Orr89RocZ

iTrader: (20)

Just bolt on and tune. Went 12.11 on a 1.66

I feel that combo was borderline perfect for a street car

You’ll hear in ls1tech how 3.73-4.11’s are big gains....didnt help me.
My L98 gained several mph and few tenths with 3.42 over 2.77

86LG4Bird

iTrader: (1)

Yep, that was damn good.
Gearing gives you good gains only when your engine is hamstrung by a tight converter.
Back when my ImpalaSS had the TC in it with stock cam and heads, going from 3.08 gears to 3.73's improved the ET from 14.0's to 13.7's.
Later, I ran a Yank SS3600 with 4.10 gears in it, still stock cam and heads, and got 1.60-1.62 60's, 12.3-12.4 ET's.