ok so im pulling the old 305 tbi engine from my bird within the next 2 months and will be dropping in a used engine from hawks third gen. i will not be beating on her.

so my question is what should i go with? the 305 tpi for 1000 or the 350 tpi for 1200? i decided on going with the 350 tpi for the extra 200 ill have more cubes and power..

which leads me to my next question. how long do yous think the t5 will last behind the 350. again i will not be using this as a street racing vehicle.

the only thing performance wise i want to do with the 350 when i get it is put a set of long tube headers on it and pulling the ac since my formula does not have that and i will be removing the emissions equipment since its going to be running long tubes into a magnaflow exhaust it will not need any of the emissions equipment. it will be tagged historically and i dont plan to drive it everyday just to school and back 3 times a week and to work when the weather is bad.


somebody please help me or give me any advice this car is my baby and i have been replacing everything i have found that does not work

 

No slicks
no shock loads (ie dumping the clutch)
no power shifting
The lighter your car - the better.
3rd gear is the weakest since it's in the center of the trans, be more careful with that than the others.

Just drive it gently and it should last you a little while. It WILL break, especially if you do any spirited driving - but you can make it last long enough to save up for a TKO or a T56 as long as you dont beat on it. It may even last a long while.

 

There was a reason the factory never fitted the T5 behind a 350

 

X2

 

1200 for a L98?

It will hold depending on how you drive. I say just get a 700r4 in there with a stall and save up for something better.

 

Good friend of mine is a tranny repair shop owner.Been in the business for over 30yrs.Toni took in the back of the shop to show me a 55 gallon drum filled with parts that he took out of T5's he rebuilt.Convinced me that isn't something I wanted to get involved with.

 

Under normal driving conditions, I agree. Mine's lasted a number of years now and I don't expect a failure.

JamesC

 

i think it will hold i see lots of youtube videos of 350s with t5s. it seems to be a mixed feeling type of thing. some say it lasts others say it will not.

those damn ford guys have those 5.0s and the t5s and they can get 300-400 hp out of the 5.0 and still have there t5 and nothing happens.. whats the deal with that. while the chevy guys are making 170hp with a 5.0 and not make that kind of power and our t5s apparently blow up with just the thought of putting a 350 infront of one

 

The Ford T5 has a much stronger transmission case. The problem with the T5 isnt the gears or the shafts or the synchros. It's that the transmission case is weak. When you dump the clutch or powershift on a T5 with anything that has some real power, the whole case bends and twists and bows like a limp noodle, and the mainshafts in the trans are able to bend in and out of alignment with each other - that destroys your gears. Gears with so much force put through them need to have very solid contact patches with each other, just like a differential gear. If the strongest parts of the gear teeth faces aren't contacting each other solidly, gears can break. There are weak areas in a gear, and when those shafts flex in a T5, the weakest points of two gears will be forced to carry all the torque of the engine against all the weight of the car - and they break, catastrophically.

THis is why that G-Force company sells those straight-cut gears. Stock gears in a T5 are slightly curved so as to minimize noise among other reasons. G-Force makes straight-cut gears. So even if the shafts bend away from each other, there's still - theoretically - a flat surface for each gear tooth to grab, and so therefore all the torque of the engine isnt going to be placed on one tiny spot, but a long wide flat spot.

Unfortunately those G-Force kits dont fix the fundamental problem with the GM T5 - the case is a limp noodle, and even those fancy straight cut gears will break eventually.

Ford's T5 has a stronger case, and Fox bodies are much lighter cars than Thirdgen camaros.

 

Yepper-looking over the back yard fence from the Astro's with T5's to the Thirdgen's-the same tranny is only rated at 170ft pounds of torque and that is pushing it some.

 

damn thanks for summing that up for me infernalvortex!!

and 1gary what are you talking about 170ft pounds of torque?

 

That rating came up in a very well informed Astro forum and was confirmed by Toni who is a certified Jasper repair station.

I got a question through.If the Mustang T5 cases are better, if the bellhousing bolt pattern is the same,couldn't you swap in a Chevy input shaft for the better case??.I don't know,I'm just thinking here.

Sure would be cool to use a 700R4 for like a yr and save,save,save,to buy a 6 speed Tremic.

 

It wont work for various reasons. Torque arm is one of them. F-body T5 is rotated a little to one side also. Do a search, I dont remember the serious details, but I remember it basically not being possible. You'd probably need a custom driveshaft also.

 

Thank you for clearing the use of a Ford case up.Yepper the Astro T5's are canted too with a special shifter and one of a kind bellhousing.

 

well then.. i think ill sell the formula and buy a fox body since they produce more power and have stronger transmissions. see you guys on the ford forums if you ever decide to switch over!!! (:

 

Swap it over to a T56.

 

i had a 355/WCT5 as my last set-up in the 91 and it worked fine, beat on it quite a bit and it never skipped a beat, as afaik, the WCT5 was rated for 330TQ. Non-WC is less, maybe 280-300?

 

I've had a t5 behind my tpi 350 for a number of years, and it gets flogged at the strip once or twice per year. the trans still feels brand new. I don't pound the hell out of it, but I don't baby it either.

 

I got a buddy with an 89 Iroc with a 350/t5 with headers and he beats on it regularly and its held up for the past couple years. I guess some get lucky and others don't.

 

I was okay with a 350 TPI T-5, it held up for a few years for me, I guess I was one of the lucky ones. I drove her daily for 2 years and I was no grandma with it either, so give it a try and save up for the 6 speed in the meantime.