LS1 vs. reg SBC install questions....

[Guest Justin]

Right now I'm weighing the pros and cons of an LT1 vs. an LS1 install. I know the LT1 is, for all intents and purposes, an EFI SBC with a front mounted distributor. The LS1, however, is a completely different animal. So I've got a few questions for the people who have done, or are pretty far into an LS1 swap.

 

First, mounting it... How far off are the motor mounts relative to a regular SBC? Do you have to measure and fabricate your own mounts, or are the mounting locations close enough that you can use the standard JTR mounts as a guide and just adjust the measurements a couple inches or so?

 

Second, the fuel system... I'm assuming you just use some miscellaneous aftermarket fuel pump. However GM, in their infinite wisdom, decided to put the fuel pressure regulator in the tank on LS1 f-bodies. Is the LS1 regulator in any way vacumn operated like on the LT1, or are fuel pressure adjustments controlled by the "fuel pulse regulator" mounted on the motor? Basically I'm just curious if you could pick up a regulator from summit and stick it somewhere on the fuel line without any adverse affects. If not, is it possible to employ parts from other LS1 cars, like the C5 or even the Holden Commadore? Also, the fuel level sending unit... Possible to use an F-body part without a large amount of fabrication/cost or no?

 

What other major snags did you come across? I'd really prefer to go the LS1 route, but it requires quite a bit of extra fabrication and cash I'll probably get an LT1 and put the left over money towards a good heads/cam package.

[Lone Star 1]

Hey Justin The console I used was out of a 97 F-body, had to enlarge the shifter hole to mount the shifter. Then I cut the front end of the 97 console off and the rear end of the 73 console off to mate the two consoles. Using the F-body console takes care of several problems. First the F-body shifter has the park, neutral, reverse switch built into it. You also have the reverse, park lockout built in. Also you can use the can't shift unless the brake is applied safty feature, that is also is built in. I payed $100 for mine. I used the JTR TPI book method to make my fuel delivery system. About a 2 cup fuel tank supplied by a 4 psi pump. Then a high pressure pump that feeds a pressure regulator that sends fuel to the motor at 58 psi and returns excess fuel to the small gas tank, there is also a return line from the small tank to the cars tank. The reason for all of this is because as the cars tank gets low on fuel, and you make turns there is enought gas in the small tank to feed the motor where as if you did not have this small tank your high pressure pump would just suck air and the motor would instanly die. All explained in the JTR TPI book. I made the AC mount in my car and mounted the AC compressor in a reversed fashion with the back of the compressor facing the front of the car. Then I ground down the middle section of the twin V belt pully on the AC compressor so that the surpentin belt would ride between the two remaining outside V belt rails. In order to make the compressor run the right direction I installed the compressor on the outside of the surpentin belt, and made a 180 deg lap around the compressor pully. I used the raditor simular to the JTR recomend except mine is all brass and cost $75. IT was a little wider and I had to cut 1/2" out of the rider side frame rail and weld a 3" x 1/2" u channel to make room for the radior. I used the steel drive shaft, its cheaper and smaller diameter making it less likly to hit things like E-brake parts. The motor mounts are different from the JTR LT1 mounts. All I did was support the motor where I wanted it, took measurments, and made mounts to fit.

[ August 20, 2001: Message edited by: Lone Star 1 ]

 

 

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Posts: 70 | From: Mesquite,Texas,USA | Registered: Mar 2001 | IP: Logged