Is there anything different about TT cams than other FI cams?

I was thinking about a 224XFI/230XER 115+2 for my TT cam on a forged 6 liter. I was told a 224/224 would work better and I dont get why. Older TT cams actually had a reverse split. I'd like to know the tech end of it if anyone feels like sharing.

 

not sure, but ive seen companys make turbo cams, and maggie cams. So im thinking there is some sort of difference, but I dont know what or why.

 

reverse splits and single patterns hold the charge longer in the chamber and helps them spool faster. Girch from LSX racing actually to date has made the most hp from stock LS2 cams.

 

I also noticed a lot of turbo cams are reverse split and wondered why, since a later IVC generally makes an engine less responsive. I figured the velocity of the shorter exhaust duration helps spool the turbo faster and a later IVC helps it pull better up top, plus the larger intake duration crams more air into the chamber to cause a greater effect on forcing it out the exhaust once it's opened.

 

Big HP cars on LS1tech seem to follow that more overlap on single pattern cams work far better and have been factually demonstrated. I want stock drivability and no lope or gas smell.

I'll look at a 230/230 114 to cover my power band. A +2 is what is in there now; 228/232 114. A 230XFI/224XFI 114 is interesting. I have a stock exhaust with the Precision 6262 and 6 liter forged. Static compression is 10.2:1 and its looking to be about 20psi. Keep in mind Im at 6800 feet elevation so our clyinder pressures are much lower.

 

the only issue with large overlap is there is a lot of flow pushed out the ex and the ex wheel has to spin much faster to reach the same level of boost and resistant to flow, ie smaller cam less overlap more boost from less wheel speed which means the compressor stays within its efficiency, if it blows over you lose power. But am sure you have taken that into consideration. A 230 cam will feel much laggier with turbos on but if thats what you want go for it.

Girch is in the 8s with 4000pounds and LS2 cam, some guys run large overlap cams and they do work but turbos have to be matched to suit plus there laggy as hell. I'm not falling into the LS1 tech results I been misguided there before, Some guys are running fast with 240s cams on 112 LSA and turbos but again only with correct turbo selection and compressor maps,

http://www.ls1.com.au/forum/showpost...84&postcount=1

This guy does very well with turbos shoot him a pm, 1013rwhp (load mainline add 15% for dynojet) stock cam, stock manifolds. He is the guru and shows the facts not fiction, though it would be of some help. The last TT LS3 I built up was astounding with factory cam, I would decompress before going bigger in cams and run more boost with smooth running and fast spool from stock cam.

 

I would look into a Dallas Performance Turbo cam. Taylor has several TT's north of 1K whp.

 

I dont know about any particular tuner's cams but anything I use will have to be shareware based so I can post specs and do DIY threads on the topic. As such, I dont need a cam speced for me nor will I ever pay for one. I want the info needed to know how to design a TT cam so I can come up with my own grind.

From what I have rsearched so far, this is one platform where just about any cam makes great power and it kind of hard to come up with one that doesnt for a turbo car.

Just about every build will have shocking numbers so there's no way to tell if a cam was optimum or not....the only way to tell that is to install two and only one will be best of the two.

For my car I am making lines in the sand already.

I'm not using a stroker that just spins tires down low in RPM. Turbo torque will do that for me and my cars all hook on the street. This will have Z06 fenders, 345 Mickey Thompsons, Z06 diff with a Z51 geared (Z06 output shaft) trans, Spec twin clutch.

I'm using a stock exhaust because I like the sound of electric cars over cammed car sounds (I want it super quiet) so I know I'm losing 30-40hp there.

I want zero lope.

I dont want the car to 'smell' modded. Yet I know a cam can make 100hp over the stocker at 800+rwhp even with no lope.

If someone wants to share some cam specs, fine, but they have to be public. If not, I'll use two guesses based on TT facts and post the specs of all of them. Eventually there will be a TT Spin cam and the specs will be shared. I am not surprised no tuners chimed in so I'll do it the way I did all the other builds...on my own. There are tuners like ECS, A&A, LG, and Dallas that help when you ask but they have their trade secrets and I respect that. I'm just going to offer a shareware version when I have it in hand because forums should be where you get free info, not just a place where you see advertisments to find a tuner.

 

There are those who know and those who say they know. I don't blame those who spent tens of thousands in materials and labor coming up with a formula that gives their shop a advantage in a very competitive market. From the same perspective, I appreciate you wanting to share infomration on this forum, which is one of the best I have come across in all of motorsports. You have the ability, so I guess you can keep trying difference cams until you figure it out. However, your requirements are very specific, so I am not sure sharing your cam will help anyone else other than a client in the high country looking for high power stock sounding cam for drag racing - pretty narrow market. Either way, good luck with your project.

 

Pay for a spec'd TT cam from 10 sources and tell me why they are all different.

Sorry if I dont buy the voodoo science end of it. Since no two tuners will give the same specs for the cam in a given build, it must be concluded that there is no formula for it.....or at the minimum, there are many ways to get a great result. If its true that my guess at a cam for this build wouldnt work on other builds then it follows that any tuner's guess would only apply to this build too.

In the end its just a guess.....for 50 bucks.

Altitude makes no difference on cam selection.

 

Well Spin I asked my roommate(mechanical engineer/race team owner) about your situation, and he believes that no one has really come up with an optimal setup for a TT Corvette because of the fact no one really races them in a competitive race series.

Anyway, his recommendation would be to run the stock cam. And if you wanted to try something you could change the intake to a bit shorter duration to see if there's any additional low end power to be had. Also lowering the compression and raising the boost would help.

 

Thanks but the established fact is that any cam will do better than the stock cam as verified by turbo threads on another forum. Average gains at 10 PSI on a 6 liter are 70rwhp with a moderate N/A cam such as a 230/230 114. I imagine similar results would be had with a 224 single pattern but with better driveability.

 

heres a shot in the dark, 224/224 115+0 straight up.

 

Well I think your going to get the most power once you lower the comp down to 9:1 so you can turn it up to at least 1 bar of boost(14.5psi).

Then you can run much larger injectors

I might be able to get you some trick injectors, and possibly some other turbo setup info., I'll talk to my buddy this week for you

 

I'm at 15-16psi now at 10.4:1 compression.
I was thinking 10.1:1 @ 18-20psi (my turbo boost target on a 6 liter).

Why do you think you need to run such low compression?

It would be a slug in the low RPM's at 9:1.

Running injectors has nothing to do with boost or compression. You can install 96lbers on a stock motor if you wanted to. Im not following you.

Anyway, I dont need info on injectors, turbos or anything mechanical. I was trying to have a cam discussion. I have done a TT APS kit up in Denver with E85/meth and 96lb injectors on a surge tank fuel system. I know how to set one up.

Does your friend have any corvette turbo experience? I dont really think there is much relative info going to come from a 2 liter motor guy. If he doesnt, i dont see how his guesses will be any better than the LS engine community that have built turbo cars on our platform.

 

Hence my guess in the first post at exactly that. The funny thing is, its been shown by Virginia Speed that more overlap cams made more power so a 230/224 115 would do beeter than a 224/224 but the driveability would be much better with a smaller cam. Personally I think your guess here is a monster TT cam.

It doesnt have a silly late IVC point making great low end, it has short Ex duration also shown to help turbos, and best yet is that it peaks at 6400 on an N/A motor so it wont fall off bad up top.

Finding how a cam's power band affects a turbo motor's top end of the same displacement is one of the things I was hoping to discuss....not have someone spec a cam for.

 

How about starting a poll?

 

A poll for what?

List 5 cams and have people vote their guess?

What exactly would people use as the basis for voting? Most TT setup owners only used one cam and they will all say their car runs great. The only people with the qualifications to vote on two cams would be tuners who wont waste time on what isnt going to be a sale.....hence why none posted in this thread.

 

Just trying to help

 

I know and wasnt slamming you. I really wanted to know what to poll.