Been awhile since I visited any information and research on TPI roller cams.
Trying to get some feedback on a more aggressive cam for my combination.

Current main components:

- Edelbrock TPI setup
- ZZ4 cam w/1.6 rr's (208/221 & 506/544)
- Trickflow 23* 195cc heads
- ProCharger w/ ~8psi

The car is fully loaded, CA smog compliant, tuned and not very fast IMO, haha.
It does run great however and sees the street and some track time.
I like the mild manners of the ZZ4 cam, but I know that can be had with a better cam and more tuning.
I've read good things about the COMP XFI's thus far, not sure which may be best though.
Should also mention I'm not looking to make power above 5500-6000rpm.

Suggestions? Thanks in advance.

 

If you don`t mind me asking what times and MPH are you getting right now?

 

A cam for a naturally aspirated application is totally different than a cam for a blower application. With a naturally aspirated engine, you need to fill the cylinder on atmospheric pressure alone. They use more overlap (intake and exhaust valve open at the same time during part of the intake stroke) in order to get maximum scavenging and filling. A blower makes extra air pressure to fill the cylinder. A cam with the amount of overlap to make an n-a engine breathe will result in your air fuel charge blowing right out the open exhaust valve at the beginning of the intake stroke. I'm not familier with the Comp XFI's, but if they work on a naturally aspirated engine, they are not designed for a blower application. The ZZ4 cam is definatly not for a blower application. You want a very mild cam to work with the blower, but if you have the necessary clearance, put in 1.6:1 rockers for more lift, or get something that would be a very mild grind but with extra lift.

 

Tony89GTA - Sad to say, with just a few runs this year the best was a 13.0@107 1.9ish 60's.
Definitely an underachiever with the mods I have, but it traps well enough for high 12's at least.

Russ-So Cal - Thanks for the detailed information.
I already have full 1.6 roller rockers as detailed in my first post.

The ZZ4 was put in well before I had thought about adding a blower and was mild as I could get at the time.

So is there something else out there that would be a suitable replacement, or should I be inquiring for a custom grind to COMP, etc?

 

i'd do a custom grind myself but first of all, you should be loads faster than what you are now

figure that out first before you go changing the cam

you could try comps blower grinds but they may not have a very mild cam for blowers

Definately want to minimize overlap. wider duration on exhaust than the intake helps too. Wider lsa makes for less overlap so you'll want to watch what your overlap is

depending on how cali emissions are with a blower, you may like something mild like a 210/224 on a 112-114 lsa or a 218/230 on a 114 lsa. That will minimize overlap but still give you great power i think.

comps nitrous/blower grind is a 224/236 on a 113 but that may be abit large for you. overlap is alittle high i feel for emissions and that blower

 

^^^ agreed. You should be moving WAY faster than you are now, even with that cam. On a completely stock tuneport setup with stock heads and around 10psi (procharger) I was going 12.5@111mph 1.9 60ft on a 95 degree day...completely UNTUNED. Before spending money on a cam swap I'd find out what's wrong with your current setup. What injectors are you running, what kind of tune do you have?

 

Orr89RocZ - Good tips, thanks.

I'm sure it should be faster, but before the blower I dyno'd about 260rwhp with the heads/cam. Prior to those 2 mods, just over 200 with intake/exhaust mods.
So the progression has been there, it's just been tougher to achieve with everything I've thrown at it.

Could have been something wrong from the start, but it's been tuned very well and runs strong I think. (24lb injectors)
Where else would I even start looking after all this time?

Not everyone has a factory freak like yourself either.

 

I didnt mean to sound like I was praising my own setup (nor do I think it was a factory freak). I can tell you what cam I was running at the time, it was the comp cams 08-304-8....the XR 266-HR14.

What did you dyno with the blower?

At the very least, if you are pulling 107mph traps you have a mid-12s car (my current build trapped 104 and ran a 12.8...no supercharger)


I still have the cam, and would offer to sell it to you except that when the blower exploded it took out most of my internals including the cam bearings...shop said the cam was fine and I believe them, I'd put it back in my own car if I supercharge it again but wouldn't risk putting someone else in a bind for $100 or so.

When you made the track pass, were you on slicks/drag radials?

 

Oh no worries, I was referring to Orr89RocZ having a factory freak as I recall him running high 13's couple years ago with nothing but a good tailwind and higher stall (or something close to that).

Yeah, based on calcs the 107 should be good for a ~12.5 and I'd guess around 325rwhp.
No dyno with the blower, no point! haha.
I've always used drag radials, I'm sure with slicks I'd pick up several tenths, but that's not what I'm looking for just yet.

 

Any other suggestions/ideas?

 

haha basically just catback/stall with 2.77's out back ...added slicks/stealth ram/gears i went 12.9's freak? maybe

260whp isnt bad with stock heads, but with trickflows it should be higher with that edelbrock TPI setup. was it a mustang dyno? who did the tuning on that setup.

i'd first look at the tuning, and check to see if everything is mechanically sound like no vacuum leaks, good plugs/wires/cap/rotor, etc.

i can see 107 mph traps with that heads/cam setup. blower should be near 112-115 depending on boost.

i know my buddies bolt on TPI car was doing mid 13's at 100 before the blower. procharger blower at 12-14 psi he was doing mid 12's at 112-114 i think before the stock internals blew. Now with rebuild, its doing lower 12's at 116 i think it is

 

Any other suggestions/ideas?

Like Orr said I would go with a custom cam. I used Mike Jones Cams for my car and I'm very satisfied. Here is a link to his web site.

http://www.jonescams.com/2006catalog_001.htm

 

Thanks for the replies and link.

The tuning is good, everything appears to run fine, all tune-up parts are a/m and in good shape.

First dyno before heads/cam was on a Mustang dyno to net 200. The latter was after heads/cam on a dynojet for 260.

I was expecting at least very low 13's after the heads/cam, but instead it was mid and I was only trapping 101.

Now with the blower I'm trapping close to 108, but a 13.0 was my best with just 3 runs at ~7-8psi. I'm sure high 12's are evident, but they should've been already.

I will look into a better cam for next season, but would really like to know if there is something that may be hindering the performance that has been hidden all this time, or if it's just because it takes a lot more to get my heavy, fully loaded GTA down the 1/4.

 

What about your exhaust? Stock manifolds and stock cat kill alot of HP with your setup.

A friend had over 600rwhp with a good old CC305 in his 383.

For a custom cam I would go with a Bret Bauer cam, next cam I will buy will be from him!

Tuned a 350, HSR, XFI268, heads, exhaust car last month, first time on strip 1.9 60ft, 12.82@106.............

/N.

 

Full Flowmaster catback and Hooker headers.

I just didn't want to bother listing them all from the start, but I've got quite a list of parts on it. Not to mention a solid suspension.

Here's some more of it from memory:

- TPI Ported, Edel low manifold + (just swapped Edel runners for AS&M)
- AFPR/255lph fuel pump/FMU/24lb inj
- 52mm TB
- Alum water pump
- Granatelli MAF
- Shift kit/2400 stall/cooler
- MSD ignition parts + 6AL
- Upgraded starter/alternator
- Tuned by local expert + myself

I'm sure a better cam and smaller pulley will help, but it sure would be nice to get more out of what I have in it already.

 

thats what i got and i like the cam so far... we'll see what the car does with it but he has a great rep for good power on LT1 cars

 

I would never to business with him again. It took him almost 2 months to ship me a timing chain AFTER I paid him. After he got my money I could never reach him at all. Go with someone better and more knowledgeable.

Have you ever used a wideband o2 sensor on the car? Not one that gets stuck in the tailpipe but had one installed closer to the engine? That might be something to check into to make sure your 24lbs injectors aren't making you go lean up top.

Also you didn't mention it, but do you know for sure that you are making 8lbs? With the upgraded top end you should be making less boost than a stock setup with the same pulley sizes. Of course you would be making the same power with less boost unless you took that into consideration and put on an even smaller pulley.

What about belt slip? Any dust or anything under the hood?

Lastly, what about a compression and leak down check? That would explain the lower numbers if there is a problem with the bottom end.

Just some things to consider.

 

Thanks for throwing some other itdeas to look into.

Yes, but only in the tailpipe while driving/tuning.

Yes, with all the mods I expected to see 6-8psi instead of the ProCharger advertised #'s for stock setups (~10psi).
Well my Autometer gauge says about 7-8 usually, but when the air is good I've seen it creep towards 9-10 when joyriding on the freeway.
I'll be going with a 3.7" pulley instead of the 4" that came with the kit shortly.
Hopefully that should give a few more psi and not blow anything.

I don't believe so, I keep it pretty clean. Belt was new and tight, have to get a smaller one for the new pulley.

That's definitely something to check into, can't recall the last one, if at all.
The car has barely 65K on it and I've owned it for 5+ years.