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Organized Drag Racing and AutocrossDrag racing and autocross discussions and questions. Techniques, tips, suggestions, and "what will I run?" questions.
I'm currently building a 355 with flat top pistions and a thumpr comps cam and going to pair it with a 5 speed. So I would like to hear quarter mile times for 350's with a 5 speed or even 6 speed. Would like to know what's been done to the car just curious mainly. I'm not going to base my times off that just curious what you guys are getting with similar setups.
When I bought my car it ran a 14.1 with a 350 +0.030 about 8.8:1 compression 882 heads, RPM performer intake, MSD distributor 30 degrees all in vac advance unplugged, edelbrock 1405 carb, roller rockers XE274 cam factory 5 speed and 3.73 rear with a Richmond locker. Summit racing 1.5" crappy headers and Y pipe 2.5" dynomax catback 225 tires on the back.
That was the baseline exactly as I bought it (horrible tuned and mismatched)I have not ran it in the current combo.
As already said forget that crappy thumper POS and get a good cam. Also roller is the only way to go.
Trouble with manual transmission performance results is it's going to depend on how hard you shift it. Considering GM never put a T5 behind a 350, don't expect one to last too long if you really beat on it at the dragstrip. They can't handle the torque. A better option is to use a T56. They will survive a lot longer.
Trouble with manual transmission performance results is it's going to depend on how hard you shift it. Considering GM never put a T5 behind a 350, don't expect one to last too long if you really beat on it at the dragstrip. They can't handle the torque. A better option is to use a T56. They will survive a lot longer.
Yeah it's mainly a just daily driver. It's not a strict drag car or anything like that. When I can I'm going to upgrade to a tko 600 just curious on times I don't expect the t5 to last driving hard. I am going to save to upgrade but I have to break in the motor so I'll be driving easy for awhile anyways. So I should have time to save.
A V8 T5 in good shape can handle the torque of an NA flat top 355 at the dragstrip, just put a proper clutch in front of it. TKO's are stronger, but too much clutch behind your 355 will kill them as well. T56 would be almost idiot proof, but why pay all that money to lug around the extra weight and extra overdrive ratio that you don't need behind your carb'd engine.
avoid the "noisy -wanna be "cam and buy one to perfectly suit your combo of heads,compression,gearing etc.
comp ,lunati and summit all have decent cams,you just need accurate info to choose the best one for you.
G-force sells a bad *** t5 case (that's the main issue with the t5 is the helical gears wanna walk away from each other and the shrimp dick case lets it happen) about $300-$350 if I recall. and Astro performance sells kits to beef up the t5. they rate their a-5 kit at 650 or 700lbft, I cant recall which, in the stock t5 case. add the G-force case and who knows??? T56s are damn nice tho!! that's whats going in mine.
have a built T56 and honestly the 6th is kind of a waste if you have any type of cam even wtih low gears
x2 on getting rid of that thumpr...these cams out with goofy names pass on them
Lots of stuff from Isky, Crower that still sound good but actually make power. Been around a lot longer too so they are proven
ill be stabbing in an LT4 cam out of a crate engine.its the gmpp 7151 cam from the sp350/357 crate engine.
an older gentleman purchased the crate engine,installed it and didn't like the fact it sounded aggressive so
he removed the cam with under a 100 km and installed a milder cam.im all about performance an a little
lumpiness doesn't bother me.i just hope the t5 styands up or ill be putting in my spare 700r4 with a vette servo.
here is the build,almost finished.just need retainers for my ls6 springs,swap the cam,timing chain,gaskets,bearings,rings and a paint job.should be good for about 360 horse and 400 ft lbs at the crank.that's close to double the old LG4's power output.
isnt the t56 good for cruising,keeping the rpms low? from my understanding they recommend a very stout gear 3.73's
are a minimum and lots of guys are running 4.11's or 4.56's.i would love a built t56,but sadly they cost as much as
another car pretty much.i just bought a parts car- L98 gta for a third of the price of a t56.(made my money back plus a ton of good parts)
comp lunati wolverine blue racer and more all owned by comp. May even own crane
Seriously get a cam taht works they will sound just as good if not better
Thumprs, the rattlers are all 70s technology. Too much work to put in something thats just for sound.
ck out isky crower etc
I ran a 9.1 in the 1/8 dragstrick a while back i didnt wanted to push it more due to knowing my limits plus i wanted to drive home and not in a tow truck
As for autocross i ran both NWC and WC and they survive well behind my 355
A T5 will only survive if you use street tires and never shock the transmission. No clutch dumps, no burnouts, no shifting as hard as you can etc. I went through two T5s. I broke the first one with my 305 TBI and the second with one of my rebuilt 355s. I would only recommend a T5 for non-aggressive driving. Don't sink any money into the T5 apart from an aftermarket shifter.
We are reaching a time when the T56 has been out of production long enough that it may makes sense to buy a new TKO 600. I'm seeing LT1 T56 sell like hot cakes at $1400. And those will most likely need rebuilt and while it's open you might as well do X, Y and Z... I have 3.73s with a T56 and 4.11 gears would still have been no problem. The highways out here are 75mph so most people go 75-85mph and I'm turning ~2500rpm at highway speeds. Had I lived in an area with lower speed limits or less open road I absolutely would have gone 4.11s.
agree on age of T56...kinda cringe when I see someone buying an unknown one paying a whole bunch for it too
They arent cheap to go through..mine cost about 1500 and was happy about it. They are 20+ yrs old!
T5 survived behind a 383 in a 56 4 door wagon for a few years. As said didnt do any clutch dumps, powershifting but held up just fine to "fun" driving.
Dont be afraid of a low gear using a T56 unless you have a TBI TPI
01-01-2019, 11:11 PM
