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LTX and LSXPutting LT1s, LS1s, and their variants into Third Gens is becoming more popular. This board is for those who are doing and have done the swaps so they can discuss all of their technical aspects including repairs, swap info, and performance upgrades.
My wife doesn't understand it either...lol She thinks I'm nuts when I clean the engine bay and underside of the car.
I think you will be happy with the LS Swap especially with the cam/heads package. It drives well and makes crazy power for factory casting heads and only 346 cubic inches. This is about as good as it gets for bang for your buck HP upgrades.
Your car should be 5-7% more effiecient with the T56 but I probably gained 15-20HP with the fast intake over the LS6. Should be pretty close on the HP/Torque numbers between our cars if the dyno factors in the altitude difference accurately. Your engine is a fresh rebuild so that could be worth a few HP too. I'll be just as excited to see your results, I'm guessing your car will make about the same or a little more power than mine.
That is too funny. I was washing the bottom of mine with suds and a mit, and she was baffled, "cause nobody will every see it"! Wives....
I fully expect to be happy. Probably more than double the horsepower of the previous engine... YEAH! Its gonna be a whole new experience, and I'm gonna have to learn to drive my car again haha!
I was thinking about the same thing, that we would be really close. If I hadn't spent so many hours sanding and filling, and sanding, and filling again, then paint... I would be all over a FAST manifold. I can't wait to get to that point. I got a lot of body work to do!
James, I'm interested to compare my results with yours when I get mine going again. Other than the cam and converter, we have very similar builds.
It will be interesting to see how our numbers compare too and how the larger cam that you have moves the power band. How long until you get back from the sand box and start working on your car again?
I think bigger cam is a tossup, mine has more duration however yours has more lift. Either way, I'm intrigued.
As for my timeline, I'll be back this summer and after two weeks of leave I'll be wrenching on it pretty good. Over leave I'll be taking a trip by mw66nova to get a rollbar welded in.
I finally took the car to the race track. It was a Wednesday night street legal event so the track had very little prep. The track was putting up cones to keep the street cars out of the groove and they had so much water in the water box you couldn't drive around it without getting the tires wet...which wasn't helping either. Had severe traction issues the first two runs and had to let up running a 13.0@114 and 12.9@115.
I switched lanes for the last run and got some traction finally 12.02@116.48, 1.89 60'. The car still has Firestone Firehawk wide oval street tires and the DA was 1935 at the time of the best run. I'm happy with the results for the first time out with this combo, it really needs a higher stall speed converter(3200 currently) and drag radials for more optimal results but I think it runs well for what it is. I didn't expect to get that close to 11's on street tires.
I finally took the car to the race track. It was a Wednesday night street legal event so the track had very little prep. The track was putting up cones to keep the street cars out of the groove and they had so much water in the water box you couldn't drive around it without getting the tires wet...which wasn't helping either. Had severe traction issues the first two runs and had to let up running a 13.0@114 and 12.9@115.
I switched lanes for the last run and got some traction finally 12.02@116.48, 1.89 60'. The car still has Firestone Firehawk wide oval street tires and the DA was 1935 at the time of the best run. I'm happy with the results for the first time out with this combo, it really needs a higher stall speed converter(3200 currently) and drag radials for more optimal results but I think it runs well for what it is. I didn't expect to get that close to 11's on street tires.
Looks like you put down some nice numbers. I struggled the same way my first outting with traction on 7 year old Cooper street tires! Mine never would bite, however. I think a 2.4 60' was the best I could cut riding the clutch hard out of the hole.
I just realized I haven't updated this thread in quite a while. I haven't done much with the car besides drive it this year. I drove it to LS fest in Bowling Green, KY and to quite a few local cruise ins.
I did add a larger B&M transcooler with a fan this spring. I installed an ultra gauge that reads trans temp from teh ECM and noticed that my trans would get hot after a couple of hard runs. The new trans cooler keeps it much cooler. https://www.summitracing.com/parts/bmm-70298
I finally made it back to the track with a set of Mickey Thompson Drag Radials (275/40-17). I'm very happy with the results 11.56 @ 117.8mph 1.62 60'. The 60' was better than expected considering the suspension isn't set up for drag racing at all. With a few minor adjustments I think I could get this car into the low 11's if I wanted to make it more race oreinted. Shift points are set pretty conservative at 6200 1-2 shift and 6300 2-3 shift to keep the 4l60e alive. My goal for this combination was to run mid 11's and have it streetable enough i could take it on trips or drive it daily if I wanted and I achieved that. At this point I don't really want to make it much faster because it is a street car and I don't want to have to put a roll bar in it.
The 3200 stall speed converter is definately holding it back from better E.T.'s but it is super street friendly. I'll probably go with a 3600-3800 stall speed the next time I take it apart to see where that puts it. I may take it apart next winter to upgrade the interals of the 4l60e, I'm sure I'm pushing my luck on the stock internals of the trans with 1.62 60' times.
That's not bad at all. You have a super clean car too, it was good being able to finally meet you at lsfest this year. Glad you are having good results with the car��
That's not bad at all. You have a super clean car too, it was good being able to finally meet you at lsfest this year. Glad you are having good results with the car��
Thanks it was nice meeting you at LS Fest too. I hope to see your car there next year!
That's the game plan, the little bit of rust I thought I had was a lot more. It was pretty severe. So I actually found another car that I am swapping everything over to, and some extras.
Just a small update. After reading about all of the comp cams trunion failures on ls1tech.com I decided to change mine out. Good thing I did because I had several were pitted and one that had a big groove worn into it. The trunion upgrade was done at the same time as the cam and head swap so they only had about 3k-4k miles and 10 drag strip passes on them. If any of you have comp cams trunions, I would suggest checking them or just changing them out. The first picture below shows the two trunions that had the most damage. Most of them had some degree of pitting and few still looked pretty good.
On a side note I changed out the comp trunions in my Dad's car too. They had around the same mileage on them with a milder cam and no drag strip use. Most of them looked pretty good but a few had some pitting that had started, they would have failed eventually too.
I went with the CHE bushings to replace the comp cams kit, I liked that design the best. The valve train is quieter with the CHE trunion kit and they seemed to rotate more smoothly.
Yikes, good catch...i may have to do the same with the new motor because it has the same trunions. I used the summit version when i rebuilt my ls1 and they were really good for the price. The clips were much thicker than the comp ones too.
Yikes, good catch...i may have to do the same with the new motor because it has the same trunions. I used the summit version when i rebuilt my ls1 and they were really good for the price. The clips were much thicker than the comp ones too.
I haven't heard any specific info on the summit version failing but it would be worth a look for sure.
Thought I would post an update since it's been awhile. I was never quite happy with the 3200 stall speed with my combination, it didn't really keep the engine in it's power band. So over the winter I pulled the engine and transmission out and made some changes. The transmission still worked but I figured it was living on borrowed time so I had RPM transmissions it. I send the torque converter to FTI and had it adjusted to a 3800 stall speed. The transmission looked like new when I got it back, very happy with the work that RPM did.
While the engine was out I decided to remove the AC. I like having AC at certain times but I used it very little so I decided to use the AC delete air box that I've had in the attic for many years. I cleaned it up and installed it. The footprint of the AC delete air box is a little different so I had to touch up the paint on the firewall.
I also installed a line lock using the kit from hawks. I've had mixed results bending and flaring my own brake lines so I decided to use the kit.
Here is where the fun begins. I ordered a set of speed engineering 1 7/8 LT headers to replace the Hawks / Stainless Works 1 3/4 LT headers. The speed engineering headers are cheap and fit awesome but if they spent just a little bit more to make them better they would be flawless. Mine S.E. headers arrived with the collectors bent and a few scratches and with a huge hole in the box. I realize they are cheap but I still expect them to arrive undamaged. I ordered them from Matt Walter and he was willing to go to bat for me and try to get S.E. to do something about it but he also said he had experienced them not doing anything about headers with more damage than this. So I decided it wasn't worth the effort and fixed them by pounding a 2 1/2 to 3in reducer into the collector to make it round, it worked pretty good. I also found that one of the flanges was warped. I took a few pics to compare the two sets of headers. The S.E headers fit better than the hawks but the build quality isn't as good.
I wasn't sure if I wanted to use the S.E. headers so I ordered a set of Hooker 1 7/8 headers. I couldn't make them work with my application, I had heard others had but I had no luck. I'm using the old Hawks/Spohn engine mounts and have an automatic, maybe that's why? I even took the motor mounts loose and lifted the engine as high as I could and couldn't get the Hooker Headers to slide in. It would require more work than I'm willing to do to get them to fit so I sent them back. The build quality is excellent though. I took a few pics to compare the header designs. The hooker mounts sit further forward giving more room for the tubes that sweep forward, that is where the interference in my case. If the Hooker system would have been around when I did my swap I would have used it though.
I ended up using the S.E. Headers. I ordered a set of V bands and a set of Jegs stainless ball and socket connections to connect the header to the y-pipe. The ball and socket's fit well so I decided to use them instead of the V bands. The V-Bands were too wide and would hit the frame, I didn't want to notch it. The passenger side header slides in easily from the top and the drivers side goes in from the bottom. The nut on the shifter linkage hit the drivers side header so I removed the nut and welded the stud to the linkage and ground all the excess material off for maximum clearance. I tucked the Y-pipe up as high as I could, it has about the same ground clearance as the old 2.5" y-pipe, the new one is 3". The cat back is the same 3.5" Mufflex i was using before. I'm not the best welder(first time building a y-pipe) but I didn't have any leaks fortunately. I used 2 sets of the stock MLS gaskets on the header flanges and they don't leak. I didn't try just a single gasket but I didn't think it was seal based upon the gap from the warp on the flange.
I also has the FAST 92mm intake ported by Land Speed Performance while I had everything apart and swapped the stock plastic power steering pulley for a Turn 1.
Car is all back together and I had it re-tuned. It made one more HP on the dyno after the changes but I think that is about right. When going from a 3200 to a 3800 stall speed there is more slip and a lower reading on the dyno, typically about 15HP in most cases from what I've read and been told when a stall speed is raised as much as mine was. I compensated for that by going from 1 3/4 LT headers to 1 7/8 LT headers and having the intake ported so my HP stayed about the same. Also the dyno had completely new software after being updated from the last time my car was tuned so it's not a true apples to apples comparison. A track test is the only way to really know how much I gained. The 3800 stall speed definitely keeps the engine in it's power band better, the butt dyno says it feels quicker. It also drives just as well with the 3800 stall speed vs the 3200. I haven't had a chance to go to the track yet though with COVID 19 shutting down almost everything. I have managed to drive the car to a couple of cruise ins though. Hopefully I'll make it to the track sometime later in the year.
03-14-2016, 01:59 PM
