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Discussion Starter #1
Hello,
2 months ago i did a swap my 91 caprice's engine to ls1 .
my transmission was a 700R4 and i had difficulties fabricating the TV cable but finally did it. last week in my way to home in the highway the third gear went off, i was cruising at 120km/h at normal rpm. So i need an advise in which transmission i most install but it should be an old school transmission without a computer. because in my country they are expensive and i need to do my harness again too. i was thinking about a th400 because it cheap and some guys said that it could handle the 330 hp but i don't know i decide to ask first.

note: stock rear end with an impala 96 rims (17/245/xx) , engine , and transmission.
and the transmission was rebuilt before one year a half (normal rebuilt not for performance in a good shop).
 

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No sure what you mean when you say 3rd gear went off, I have to guess you mean it failed.

The 700R4 and 200R4 transmissions require the throttle valve cable to be pulled the correct amount and rate during throttle operation. Here is a link to a page that has some good info on the correct angle for the cable bracket.

700R4 Info Page 1

If your cable bracket on the throttle blade doesn't fall in the correct range, there is a good possibility that the trans could be burned up due to incorrect pump pressure.

The 700R4 was upgraded many times during its run and in the end, had so many changes made that GM changed it's designation to 4L60. The 4L60E requires a computer since it is electronic, the non-E version is cable operated.

The 1989 up versions are considered best for performance builds. The 92 up versions had a secondary valve body, but that was supposedly only there to aid in rocking the car if it was stuck in mud or snow.
 

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330hp is an easy goal; the stock LT1 put out that much in the Corvette. Due to the crossmember location and making things simple on yourself; I'd simply rebuild the 700r4 with some mild performance pieces (you shouldn't need any obscure or expensive specialty parts).
At the same time, I'd increase your rear gear ratio if you have not already. The single best thing you can do with a Caprice, is give it more rear axle gear. Its a big, heavy car (I love them), and the highway cruising axle ratio can put a lot of stress on the transmission if you drive the car aggressively.
The third thing I would do is find a stock GM torque converter with a slightly higher stall RPM to help move the car along with the new gear ratio. Something like a 26-2800 RPM stall and 3.55:1 rear axle gears, plus a quality rebuild on the 700r4 and maybe an external transmission cooler should make for a really fun driver and it should last another 20 years.
Your Impala is 21yrs old and you may not know its maintenance history (was the fluid changed, was the transmission ever run low on fluid). Its failure may not have much to do with the TV cable at all, but definitely have the guys here doublecheck your geometry before we go too far.

Just my opinion.
 

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I'm betting that he did a carb conversion when he installed the LS1. The original computer in the Caprice would not have supported the LS. If he had included the LS computer, he could just use a 4L60E and eliminate the cable altogether. I don't think we have enough details yet.
 

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Discussion Starter #5
I'm betting that he did a carb conversion when he installed the LS1. The original computer in the Caprice would not have supported the LS. If he had included the LS computer, he could just use a 4L60E and eliminate the cable altogether. I don't think we have enough details yet.
really appreciate your respond man ♥


I took the harness out of a caprice 2004 or holden statesman(in my country called caprice from 00-16) and modify it without the transmission sensors.
So if I want to but a 4L60E on it , I must buy another harness and modify it again and it will costs a lot.
And yes i did not change my rear end so , should the rear end for a 96 impala hold that power ?
if yes i will look for it . it's hard but i will try.
And what about the 700r4 ? Did i have to rebuild it or go with the 400 transmission? because i can find it in the junkyard for a 190$ guaranteed for a week.
Because in my country if you want to rebuild it will cost a 670$ at least also I don't know if they do performance builds and i'm a college student and putting my money on it so i'm trying to spend my money as cheap as possible but not in a bad way or parts.
 

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First choice th350 perfect gear ratios second is th400. Both since not a built ls would be standard stall or 2000-2400 stall if you plan on programming changing rear and long tube headers. Get it flash programmed for the timing change. It will run great. 700r4 is all around tranny but has to be (built) heavier clutches stall etc. my 383 has th350 behind it great tranny haven?t blown it yet.
 

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Maybe I should be more explaintive on y a 350 or 400. 700r4 has to be built to handle the 500+hp, yes they do have the overdrive gear which is great highway cruise but races aren?t on the highway getting a perfect match all the way thru is a challenge. Most new age Camaros etc can?t get you off the line but at the end there catching up at that time the race is over so choice is ultimately up to you. The new 6 speeds are getting to that perfect curve but price is nuts. IMO Where in the US is it a constant you can cruise 125 mph. Nowhere so I see no point I criuse at 80 2600 rpm all I really need to do is step down and power is there no lag no downshift skip nothing. But as I said each there own, everyone?s style is different there feel they like or have so no answer is incorrect, money time and forethought and checking the numbers twice is always best IMO.
 

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Just a small correction, the only GEn 2 engine to make 330hp is the LT4. The LT4 was available in 1996 Corvettes, and only if that Corvette had the ZF 6 speed manual trans option. The highest output GEN 2 LT1 in the 1992-1996 C4 Vettes was 300hp, in fact all the years between 1992 and 1996 were rated at 300hp.
You could also get the LT4 in the 1 of 29 built LT4 Firehawk and the 1 of 106 LT4 SS Camaros. These were special LT4s as they were all disassembled and balanced and blueprinted and had their engine bores honed with a torque plate installed, a process that the remainder of the total 6490 LT4 engines produced, did NOT have done to them. Every engine was dyno tested and every 5th car was ran on the chassis dyno. In order to retain the 330hp @5800rm/340lb/ft torque @ 4500rpm rating that the LT4 had in the Vettes without offering up a custom calibration(which would have made GM emissions test the F-body LT4 combination for a small run of under 150 cars=cost prohibitive) specific exhaust manifolds were sent out for Extrude honing and a specific LT4 high flow exhaust was used.
While the LT4 had a power peak at 5800rpm, its fuel shut off occurred at 6412rpm. Engineers found out that the rocker arm balls/cups on the stamped steel rocker arms would gall at over 6000rpm,(not an issue on the 92-96 LT1 engines as they had a fuel shutoff at 5800rpm) so GM enlisted Crane to build some narrowbody, self aligning 1.6:1 ratio full roller tip and roller fulcrum rocker arms for the LT4. There were some initial issues with these rocker arms which resulted in 2 recalls of LT4 powered Corvettes. Owners were told not to drive their new Corvettes and get them towed to the dealerships for retrofit. Because of this, GM has never offered an OEM roller fulcrum AND tip rocker on any future GEN 3, 4 or GEN 5 SBC. Though they commonly offer a roller fulcrum rocker with the satandard tip that slides on the end of the valve stem.

The LT4 Firehawks and LT4 SS Camaros were a very special breed indeed.

EDIT That video states that GM Corvette division wouldn't allow the LT4 Camaro/Firejawks to wear the Grand Sport throttlebody plaque. In fact all LT4 F-bodies have the Grand Sport throttlebody plaque.

peace
Hog
 

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Im not entirely sure why people are telling the OP to worry about "500hp" when nothing he has posted in this thread reflects A. dedicated drag racing, or B. 500hp

Removing the 700r4 and moving the crossmember, possibly changing the driveshaft and slipyoke to install a TH350 or TH400...when all he needs is some upgraded quality rebuild parts installed by someone with experience in 700r4's is kind of silly.

Upgrading the ring-n-pinion ratio in the existing axle housing (if possible) from the (probably) 3.23, to a 3.55/3.73 will make the car accelerate quicker, put less stress on the transmission trying to lug this heavy car around, and be a lot more fun to drive; without digging into the motor for "500hp", reprogramming the ecu or screwing around with driveshafts, crossmembers and slipyokes. Anything numerically higher than the 3.55 should have an updated torque converter but its not required.

DEFINITELY, if you keep the 700r4, verify your TV cable angle.
 

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Discussion Starter #10
Thanks for everyone for responding especially Hotrod46 and AutoGear .

I need summary to this thing. Because I will explain my situation here.
Try to find a th400 in the junkyard or I will look for shop which can built 700r4 and ask for the price. And what I understand that I have to look for rear axle (diffirential gears with 3.55:1 ratio (help me with the name of the car that I have to take the gears from) ).

My choices are:
1- building 700r4
2- buying th400 from junkyard. 'probably out of suburban or maybe a van which is (very rare)'.

Please tell which option is better for the budget
and if I bought the th400 and put it to the car
what is the advantages and disadvantages ?

building the 700r4 what should I do ?
And will it handle the power or will it fail?
Finally the TV Cable what can I do to the throttle to hook it probably?


Sorry I know that I am afraid of the failure of the 700r4 but because some people were saying that it can't handle the aggressive drive and accidentally it fails on me.
 

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you already have a 700r4. I appreciate Hogg's experience with the LT engine, but my point is the same. The 700r can handle 400hp easily, if built by someone who knows what they're doing, without needing hard-to-find parts; and be daily driver friendly.
The Turbo 400 (TH400) can handle way more power, but you lose the aggressive 1st gear, lose the overdrive, might need a new shifter.

If you can find someone in Europe who can reliably build a performance-oriented 700r4, thats the best course of action. If you cant find someone, and don't want to import the transmission; you'll have to try to find a TH400 in good repair I guess. Me? I'd fix what I already have.
If you decide to rebuild it yourself, there are several very qualified guys in this forum to help you. But you'll need a couple specialty tools (pressure gauges and whatnot).
 

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I'm with Autogear. A stock build of every 700 will handle upto 400 ft/lbs. What is the throttle body you're running? Perhaps a picture would identify your TV cable bracket geometry. The best way to confirm correct TV travel is with a line pressure gauge.
 

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Discussion Starter #15
I appreciate everybody in this forum especially who help me.

Now, I did search locally in trans shops and asked if I rebuilt the 700R4 what are the parts they gonna but in the transmission , they basically said that if I went to every shop or spare parts store that i will not find GM parts.They said that the parts are made in USA but my transmission was built in same parts and didn't last for 2 years.

So basically the solution now is to try to find a th400 ?
and if i went to the ls1's transmission (i think 4l60e) what i need to do with the harness ?
Do I have to modify new harness or what ?
 

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I think the T 400 is your best choice for the situation. You will give up the overdrive but you still should be able to keep up with traffic. A converter in the 2200-2400 stall range would be better but probable not absolutely necessary. You give a little off the line acceleration but over all a void T 400 is a very durable transmission even in a stock rebuild. You could install a shift kit to firm the shifts. You may need a governor kit to adjust the shift points to your liking.
 

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holden statesman(in my country called caprice from 00-16
I'm thinking South Africa for country with a Holden/Caprice. If you use a T400 there is no TV cable, or a Kick down cable. Kick down can be done with a microswitch on the throttle linkage.
 

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If you go with the 700r4, the cable geometry must be set this way.
The peg. the plastic wiper slots into, is positioned 1(one)inch from throttle shaft, @ the 5;30 position and swings to 7;30.

When adjusting the cable, make sure gas pedal inside truck will fully open carb/throttle body.
Then adjust it so at a creeping light throttle 1st to 2nd shift , it will downshift back to first, when you floor it.
Sometimes you have to wind a small spring onto the end of the cable, to keep it from ratcheting the cable in.
 
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