I went to go look at a car today, it was an 88 T/A (light 355, t5 in maui blue/silver, so its kinda a rare color too... Bonus!). The car itself needed a little work, but ran decent and is pretty straight. the motor, as stated by the previous owner, is out of a camaro, so its an l98, and has been worked over into a 355. It has aftermarket heads, some sort of edelbrock tpi, and a bigger cam. I want to see if it is capable of some higher rpm driving with a new intake manifold, and am curious before I might buy the car.

Personally, I love high revving v8's, and when I get the right third gen, eventually, I want to do a destroked ls7, just like detroit speed engineering's DSE-Z camaro... the sound of an ls at 8500+ is amazing, and coming from import cars, I'm used to higher revving motors anyways.

Knowing the tpi manifold is the weakest point of higher rpm driving in these cars, what is the best intake that will allow higher rpm driving without spending an arm and a leg? Keep in mind I wouldn't not shooting for 8k+ for this motor, but rather something close to a 7k redline would be nice as I'm fairly sure the motor could handle it.

I know of:
tpis mini ram: seems to be a good option, but costs a lot
super ram: haven't seen much on these, but I know a user pwdbychevy uses one on his turbo dart block satin black z28
holley's stealth ram: also costs alot
Edelbrock air gap: haven't really heard much on these either


Any input on those, or other suggestions would be great. Thanks!

 

You've covered a lot of territory with the manifolds listed. Are you intending to from EFI to carb? Or from TPI to a TB/with a wet intake style induction or multiport?
As for 7000 RPM, depending on the mix of parts you have, it may be a useless endeavor if it's just for the sake of the sound. If you're making peak power north of 6500, and that requires a pretty healthy cam and heads, then 7000 could be a reasonable redline.
I can't comment on the EFI manifolds other than reporting back on what this forum has to say.
As for the more conventional intakes: the two plane RPM Air Gap arguably has an RPM range up to 6500. Beyond that, you get into single plane intakes like the Victor Jr., advertised to 8000 RPM and the Victor which is listed at 8500.
A 1" inch spacer on top of the two plane Air Gap has shown to move the usable RPM range up somewhat.

 

This car will end up being my daily for a while, so the goal would be to keep it fuel injected for slightly better fuel mileage. As far as I know, the motor is recently rebuilt, so a healthy cam and heads would be a given, though I will probably crack open the motor to be sure. The higher redline would be to help increase horsepower. Since the formula for hp is tqxrpm/5252, if I increse the redline some, obviously I would be able to acheive a higher hp number than it currently is due to the torque-y nature of a tpi intake, all without changing much on the motor. Thanks!

 

The higher RPM equaling more HP only holds true if the engine makes power at the higher RPM.
My earlier 355 made peak HP around 5500 RPM. While it was capable of 7000, going there did nothing for better strip results. Enter the new cam and ported heads and peak HP is now closer to 6500. 7000 makes sense.
From my understanding, while the TPI does make excellent torque numbers, it produces them a relative low RPM. The 5252 multiplier is applied to a lower number (torque peak) and so high RPM HP results are never realized.
Now take that same engine, change the cam and induction so that peak torque will move up the rev range and so will the HP and output.

 

It's not going to last long at 7000+ rpm, nor is it going to make more power. In fact spinning the engine you have now up to 7000+ rpm will make less power than at 4500-5000 rpm.