Bill,
I definitely understand. I've yet to find the tree that has U.S. currency for leaves :laugh:.
I'm just ready for you to get your kit so I can follow your progress.
Rumbles SLC Build
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Bill,
I definitely understand. I've yet to find the tree that has U.S. currency for leaves :laugh:.
I'm just ready for you to get your kit so I can follow your progress.
Re: Transaxle and Rear tire selection
I'd think anything under 325 int he rear woudl look a bit anemic. I had the 335 nitto's on the back and they filled the wheel wells perfectly. unfortunatley you got a bit of interference so i had to jack the shocks up a bit further. i'd think 295 in the rear would look odd. 315 wimpy... imo
Yup, I spoke with California Motrosports yesterday. That's where I got the estimate for the ring & pinion swap.
I'm widening my thinking to include other alternatives:
- There is a Porsche salvager here in NC that will give me a hand in finding a tranaxle that fits my needs.
- I'll look into other transaxle options such as Griffin, Mendeola, etc.
- One option is to mount taller rear tires. This may be a nutty idea but here are some possibilities
Your thoughts?
I'd think anything under 325 int he rear woudl look a bit anemic. I had the 335 nitto's on the back and they filled the wheel wells perfectly. unfortunatley you got a bit of interference so i had to jack the shocks up a bit further. i'd think 295 in the rear would look odd. 315 wimpy... imo
On to the rest of the powertrain
I pursued the transaxle first because I expected that to be the most difficult item to find. Now that I bought a G50/21, it’s on to the rest of the powertrain. The objective is to have the entire powertrain together and ready to drop in when the SLC hits my garage door.
I’ve started searching for a used LS3, or a LS2 as Plan B.
But seriously, the difference in price leave lots of room for some LS2 power adders.
I pursued the transaxle first because I expected that to be the most difficult item to find. Now that I bought a G50/21, it’s on to the rest of the powertrain. The objective is to have the entire powertrain together and ready to drop in when the SLC hits my garage door.
I’ve started searching for a used LS3, or a LS2 as Plan B.
- The LS3 is somewhat rare and priced accordingly. An LS3 full pick with Assy drive, E-pedal, ECU, O2 sensor, MAF sensor, harness, etc is about $6-10K. That seems a bit high since you can buy a new LS3 with warranty for about $6k. However, you need to add all the peripherals (Assy drive, E-pedal, ECU, O2 sensor, MAF sensor, and harness).
- The LS2 is more plentiful and about half the price.
- The LS3 has 430HP and the LS2 has 400HP.
But seriously, the difference in price leave lots of room for some LS2 power adders.
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there is a cheaper way to put it together too if you don't mind doing a little more searching and understanding how/what can be put together. I'll admit there are a lot of nuances that get in the way, but it's nothing someone hasn't solved already. whether it's 24x vs 58x, dbw vs. cable, active valve timing, different cam covers, different knock sensor locations, etc. It may seem overwhelming, but pick your engine and then see what it would take to put it in the car.
If you are set on a ls3, keep an eye out on the SLP ebay store. They will have ls3 shortblock on their website for about 2500 pop up here and there. You can buy ls3 heads with valve train for about 800-1000 so you could effectively have a longblock for less than 4k. That leaves you room to buy a intake you want and throttlebody you want.
I'd skip the MAF and go with a SD tune. There are a lot of guys getting these engines to run extremely well on SD tunes.
Also from a pullout you can go for a L76 and L92, both aluminum block/head combos that would work. You can also use a car intake and a cable tb, those are easily changed over while everything is out.
Not sure what the jury is on which oilpan will with in the SL-C.
If you are set on a ls3, keep an eye out on the SLP ebay store. They will have ls3 shortblock on their website for about 2500 pop up here and there. You can buy ls3 heads with valve train for about 800-1000 so you could effectively have a longblock for less than 4k. That leaves you room to buy a intake you want and throttlebody you want.
I'd skip the MAF and go with a SD tune. There are a lot of guys getting these engines to run extremely well on SD tunes.
Also from a pullout you can go for a L76 and L92, both aluminum block/head combos that would work. You can also use a car intake and a cable tb, those are easily changed over while everything is out.
Not sure what the jury is on which oilpan will with in the SL-C.
Th LS2 has a better bottom end too. As I responded to an earlier post from Troy, as the LS1, the LS2 with the right cam/springs/pushrods (hardened ones) can easily get you to much higher levels. They like reverse split camshafts, such as the ASA cams available from GM (hint).
The cam in my LS1 is sort of radical at 230/224 .575/.563 with 108 LSA.
It sounds awesome!
good point, i excluded these because they are iron blocks. The weight difference is around 100-120lbs if I recall.
i hear you, iron block combo is the biggest bang for the buck, no argument from me as I have one of the combos in my camaro. My only thought on still pushing an aluminum recommendation is I assume Fran designed/tuned the suspension based on the aluminum engine being back there. Not sure if any of the suspension settings would change based on the extra weight.
A key design theme of the SLC is lightness with its aluminum chassis and few frills. The iron block is a wallet tempting option. But in a 2200lb car, the additional 100-120lbs seems like a weight penalty that is not worth the $$$ savings.
That's like carrying around a second girl friend all the time, without the benefits:gorgeous:
In comparing the 2 options, the iron block adds 5% to vehicle weight, while the LS3 has 7% less power. So the power to weight ratio is nearly identical. However, with the heavier iron block you risk loosing some of the SLC sprightly handling characteristics.
That's like carrying around a second girl friend all the time, without the benefits:gorgeous:
In comparing the 2 options, the iron block adds 5% to vehicle weight, while the LS3 has 7% less power. So the power to weight ratio is nearly identical. However, with the heavier iron block you risk loosing some of the SLC sprightly handling characteristics.
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SD vs MAF Engine Mgt
Merim,
In your post below, you mentioned Speed Density (SD) Engine Mgt. I was not familiar with SD so I did some reading on it. There are lots of opinions out there on SD vs MAF, but the consensus seems to be:
Merim,
In your post below, you mentioned Speed Density (SD) Engine Mgt. I was not familiar with SD so I did some reading on it. There are lots of opinions out there on SD vs MAF, but the consensus seems to be:
- You can squeeze out more peak power using SD. However, SD tunes are less adaptable to changes in barometric pressure, altitude, vacuum line leaks, etc. This may result in some driveability issues.
- MAF is more adaptable and can compensate to produce more consistence performance.
- GM tried SD on some select production models, but has gone back to MAF. Speculation is that there were more customer complaints with the everyday driveability of SD.
- SD is a good choice for track cars where peak performance is important, at the cost of more frequent dyno-tunes.
- MAF is a good choice for street cars where every day driveability is important, at the cost of a few peak HP.
Re: SD vs MAF Engine Mgt
Fair points above.
I wouldn't say SD is for track only though, I would run it on the street without issue and have driven several cars that are that way. The throttle response is much crisper with SD vs MAF in my opinion, do some searching on driveability and see what you find. SD also helps tame larger cams to get more precise on the tune so improved drivability with bigger cam as well.
Also keep in mind a MAF will not help with a vacuum leak either. That is air being introduced after it is metered and therefore the computer doesn't know about it and will not adjust to fix it. If you're altitude is changing a lot, I could see where SD could be challenging, but my home is in the midwest and I rarely drive the cars outside that altitude area.
My point in commenting on doing SD is it will help you save cash in sourcing the MAF and still being happy with a solid tune. This is my opinion, I'd tell you to reach out to this guy, he does this for a living and does mail order tunes, I will use him to get my initial SD tune on the L33 in a few years when i'm ready to start this project. TunedByFrost.com - Professional Tuning For Your LSx Powered Car or Truck
Fair points above.
I wouldn't say SD is for track only though, I would run it on the street without issue and have driven several cars that are that way. The throttle response is much crisper with SD vs MAF in my opinion, do some searching on driveability and see what you find. SD also helps tame larger cams to get more precise on the tune so improved drivability with bigger cam as well.
Also keep in mind a MAF will not help with a vacuum leak either. That is air being introduced after it is metered and therefore the computer doesn't know about it and will not adjust to fix it. If you're altitude is changing a lot, I could see where SD could be challenging, but my home is in the midwest and I rarely drive the cars outside that altitude area.
My point in commenting on doing SD is it will help you save cash in sourcing the MAF and still being happy with a solid tune. This is my opinion, I'd tell you to reach out to this guy, he does this for a living and does mail order tunes, I will use him to get my initial SD tune on the L33 in a few years when i'm ready to start this project. TunedByFrost.com - Professional Tuning For Your LSx Powered Car or Truck
A great option but I would rather save 5-6K and have the same hp or better. Im going to be on a budget though.
I don't think you're going to be able to build 550hp and have it complete and running for 4k?????
Its been done already:
Testing The New GM L92 Cylinder Heads - Car Craft Magazine
This is also only using the LQ4 which has lower compression. Find an LQ9 and you can have even more. You can buy these engines complete for cheap and for 4-5K you can have it running strong.
