ls1 vette motor in my 69 ,same power or slower than the old 307..why

[chevnut55]

I have a 10,000 mile 01 vette ls1 motor in my 69 Camaro, and its is a big disappointment so far.
The motor runs great, no hesitation or problems, It has no smog stuff, dynatech headers, flowmaster exhaust, good aftermarket plugs and wires and good fuel system/injectors. The trans is a new level 2 4l65e. it has 3;73 gears.

It seems about the same power as the old 307 /glide that was in it except for sound and highway rpms.
It shifts slow and weak, and bailey has enough power to spin the tires. I brought it to 2 programers and the harness guy programed it (incorrectly) but neither had it on the dyno, they just kept wanting my to bring it back and pay more. after the 2nd guy got it running good but blew the trans I gave up and decided to just drive it.
could a good tuner really wake it up or did I just waste a lot of time and money?

[protour_chevelle]

It needs to get on the dyno, proper tune by a knowledgeable person. It sounds like there is transmission issues. If there is a stage 2 transmission in it, there is internal work done. Transmission tables have to be adjusted in the tune.

[68lovebuzz]

Who did your harness? There has got to be a tuning or wiring issue.

[Z06vet]

Even if the LS1 is bone stock it should not even be on the same planet as 307. Should haze the tires thru first & most of 2nd if they are street tires. Something isnt right. It may be worth your time to drive or trailer the car to a reputable tuner. Dyno isnt necessary if the tuner has a wideband setup for the laptop. Its just easier(safer) on the dyno sometimes for the WOT pulls.

[68lovebuzz]

I agree ⬆

[chevnut55]

The 1st tune I cant mention ripped me off and screwed up the tune and now bad moths me on here so I can not mention his name on here because hes now somehow a vendor but he is a lying POS.
The 2nd tuner was suppose to be the best around my area and probly is but could or would not be bothered with other issues . I brought it to him 2 times and once to get it running after the harness guy re set the vats after he mess it up the 1st time he programed it.
I brought it to another guy who fixed some issues I could not and got t running good but smoked the trans on me and could not dyno it.
so now I have way over $1k in tuning I do not trust anyone with my car anymore and hate owing something I can not fix myself or have to leave my car anywhere.
Its mostly the area I live in to find someone honest who gives a crap so I might wait until my house sells and have someone in the tampa fl. area do it correctly.
Im just glad I can drive it now after all I have been through but wish I kept a older style motor.

[68lovebuzz]

Yeah I was just curious if you built the harness or bought one made. Do you have a CEL? Throwing codes?

[71maroesteban]

If I was you I'd take of the efi and put a carb you'd put so much money to get that motor in and you can't even enjoy it car engine computers a pita

[68lovebuzz]

Regardless of carb he still needs a PCM for spark.

[Mr.VENGEANCE]

some foulplay involved... stock ls1 is leaps over a 307

[regal454]

Why don't you look into the Holley EFI or MSD Atomic EFI? They both have self tuning capabilities and a are plug and play. I have the Holley HP EFI system and love it. It was literally as easy as connecting 5 wires. Plus, any future engine changes you make will not require expensive dyno tuning. Also, I believe the Holley system has the ability to control an auto trans.

550-602 24X reluctor wheel (GenIII)
550-603 58X reluctor wheel (Gen IV)

Don't throw in the towel on the LS, once you get it running right you will love it.

[Z06vet]

I wouldnt buy anything else at this point. Tuning a stock motor should not be that difficult if there are no other underlying problems. Hang in there, even if you have to wait until you move. If you want to do some research or see if there are any other tuners near you, check out ls1tech.com. Before you take it anywhere else, maybe give them a call & get feel for the experience they have dealing with swaps, troubleshooting, and tuning the setup you are running. That car should be a blast to drive, even stock.

[chevnut55]

My house is for sale now and cant put anymore $$$ into it. Im having problems with my vintage air retro sound stero now..its one problem after another.
I did want to drive it from here in ma. to fl. when I move but I do not want to ruin it with a bad tune.

[67rally]

I know one of the guys who did your tune, he's the one who did mine, and the one I would have recommended. But I do understand your feeling like they don't really give a crap.

Where'd you get your harness? I got mine from PSI conversions out of NJ. You can send them your ECU and they'll put a custom tune on it for $150 or so.

[68lovebuzz]

Same here. PSI was literally plug and play. Wire it and fire it. Came with custom tune on PCM. the tune included ls6 with headers, fan temp command, and a few other details. I had the coil pack sub harness originally installed wrong. It ran but had no power and missed occasionally. I looked at my LS subharness in my silverado and compared coil pack wire colors to get it right. Runs like a Swiss watch now.

[badazz81z28]

The LS1 is not as powerful as some people may think...Stock form,they would dyno about 315 to tires in the 4th Gens. Mine is not as peppy down low as my 350 was.

Yours does sound like there could be a tune or fueling problem as it should have some decent DD power.

[andrewb70]

If I was you I'd take of the efi and put a carb you'd put so much money to get that motor in and you can't even enjoy it car engine computers a pita

This is the worst advice ever…

A stock LS1 will put down at minimum 300rwhp, which is about 175 more than a stock 307.

I recall the OP having all kinds of issues with this build. If the OP doesn't have the skill and ability to diagnose this problem, he should take the car to a competent mechanic and tuner and figure out what is happening.

I would start with the basics, spark, fuel pressure, dyne runs with a wideband, and transmission tuning…

This combo should lay down rubber for as long as the eye can see.

Andrew

[67rally]

I recall the OP having all kinds of issues with this build. If the OP doesn't have the skill and ability to diagnose this problem, he should take the car to a competent mechanic and tuner and figure out what is happening.

That's the problem though. He has taken it to one of the top tuners in the Northeast, and didn't get the desired results.

[chevnut55]

If I can come up with more $$$ I might bring it back to slowhawk since he is the best around and its now the slow season.
He could not do everything I wanted because of a brake booster leak and a few other things I could not figure out that he doesn't do, like the tach and ac /fan. but he did get the trans shifting great until the next guy blew the trans before he could dyno it but he did get everything else fixed and made it stop stumbling and idle smooth.
I do not care if its a race car as I have a blown big block 55 chevy to go fast straight and a 13 vette g/s to burn corners.
But it does seen to be a waste of time and money to not have this car act like a proper muscle/pro touring car.