Don Terrill’s Speed-Talk

BOOT wrote: ↑Mon Sep 02, 2019 4:11 pm

SpeierRacingHeads wrote: ↑Mon Sep 02, 2019 11:33 amThe OEM TPI is great for a street rod. It has a timeless classic look, and some might say ahead of it's time. However performance wise it's a disaster, IMO. The bottom isn't even big enough to match the factory head, and you can't port it big enough without weld.

A bit harsh, the problem is most don't build to it's strengths and try to make it do what it won't. Still most the time I try n caution anyone not to go too big on a combo piece they just go bigger! People always think my C4 is a LT1 car cause I beat basic moded LS cars and it's fun to pop the hood n show them the TPI.

Where does your engine peak with the OEM TPI? 46-4800?

SpeierRacingHeads wrote: ↑Mon Sep 02, 2019 4:14 pmWhere does your engine peak with the OEM TPI? 46-4800?

I already told the guy to get another intake and the TPI was a money pit AND I think it's good for a mild street car, the guy wants more than mild so....
I'll even go one further, my car would prob be a lil faster with a different/better intake but not by much for how I have it set up.


Oh and to the OP, I forgot to suggest a carb intake and fitech or sim TB, still tight fit, so I'd used shorter type dual plane like maybe a brodix but not like you got air bleeds to worry bout.

There was a company that sold modified gen II LT-1 efi intakes modified to fit and run on a gen I block/heads.
A lot more power, like a mini ram.

More cr + 219° 219° .560" hyd roller + headers + fully port+ 2.00/1.56 your 113 heads. 10.5:1 cr

You may be able to find this modded LT-1 intake used or a used mini ram.
A shortened stealth ram/weiand hi ram base with custom low height plenum top will work well too.
A shortened Edelbrock tunnel ram base with custom fabed plenum top is another path.
Must add injector bosses.

BOOT wrote: ↑Mon Sep 02, 2019 4:34 pm

SpeierRacingHeads wrote: ↑Mon Sep 02, 2019 4:14 pmWhere does your engine peak with the OEM TPI? 46-4800?

I already told the guy to get another intake and the TPI was a money pit AND I think it's good for a mild street car, the guy wants more than mild so....
I'll even go one further, my car would prob be a lil faster with a different/better intake but not by much for how I have it set up.


Oh and to the OP, I forgot to suggest a carb intake and fitech or sim TB, still tight fit, so I'd used shorter type dual plane like maybe a brodix but not like you got air bleeds to worry bout.

The big tube ported aftermarket base tpi stuff will make his power. It will peak 4400-4600 and hold to 4800-5000 but its been done many times. Welding the base up and raising injectors up to gain cross sectional area is the only way to really get more out of them systems

Putting a aftermarket hood on the C4 Vette really opens up the possibilities.

Orr89rocz wrote: ↑Mon Sep 02, 2019 7:17 pmThe big tube ported aftermarket base tpi stuff will make his power. It will peak 4400-4600 and hold to 4800-5000 but its been done many times. Welding the base up and raising injectors up to gain cross sectional area is the only way to really get more out of them systems

People act like it peaks and drops like a rock! More like a very slight peak and then it flatlines and that makes the ave power still decent, if your ignition and valvetrain are good.

I still think longterm higher hp goals and how people buy parts that support narrow high rpm a better intake is a safe bet.

BOOT wrote: ↑Mon Sep 02, 2019 10:25 pm

Orr89rocz wrote: ↑Mon Sep 02, 2019 7:17 pmThe big tube ported aftermarket base tpi stuff will make his power. It will peak 4400-4600 and hold to 4800-5000 but its been done many times. Welding the base up and raising injectors up to gain cross sectional area is the only way to really get more out of them systems

People act like it peaks and drops like a rock! More like a very slight peak and then it flatlines and that makes the ave power still decent, if your ignition and valvetrain are good.

I still think longterm higher hp goals and how people buy parts that support narrow high rpm a better intake is a safe bet.

I don't think it drops like a rock. I also have a '85 IROC with a 215hp 305. To be honest it runs damn good. I think they get a bad rap myself.

Want the sale? I need a guaranteed to work and play nice together package I can bolt on in a weekend, then throw on trailer and take to dyno to be tuned, unless of course there is a package with custom parameters chip you sell..?? You come highly recommended sir.

Edit* thought I was quoting Chris Spier sorry guys. I like the heads cam intake approach, then I can have a 383 built for when he kills this thing in a year or two of flogging it.

BOOT wrote: ↑Mon Sep 02, 2019 10:25 pm

Orr89rocz wrote: ↑Mon Sep 02, 2019 7:17 pmThe big tube ported aftermarket base tpi stuff will make his power. It will peak 4400-4600 and hold to 4800-5000 but its been done many times. Welding the base up and raising injectors up to gain cross sectional area is the only way to really get more out of them systems

People act like it peaks and drops like a rock! More like a very slight peak and then it flatlines and that makes the ave power still decent, if your ignition and valvetrain are good.

I still think longterm higher hp goals and how people buy parts that support narrow high rpm a better intake is a safe bet.

Yeah it can certainly make average
Heres the one tpi hot cam car i tuned.

Orr89rocz wrote: ↑Tue Sep 03, 2019 7:13 am

BOOT wrote: ↑Mon Sep 02, 2019 10:25 pm

Orr89rocz wrote: ↑Mon Sep 02, 2019 7:17 pmThe big tube ported aftermarket base tpi stuff will make his power. It will peak 4400-4600 and hold to 4800-5000 but its been done many times. Welding the base up and raising injectors up to gain cross sectional area is the only way to really get more out of them systems

People act like it peaks and drops like a rock! More like a very slight peak and then it flatlines and that makes the ave power still decent, if your ignition and valvetrain are good.

I still think longterm higher hp goals and how people buy parts that support narrow high rpm a better intake is a safe bet.

Yeah it can certainly make average
Heres the one tpi hot cam car i tuned.

What all did the combo consist of?

Stock shortblock 87 L98 350

Box stock afr 180 heads
Tpis bigmouth base basically box stock no porting, already was 1205 ish gasket like the heads
AZ speed and marine large runners
Matched plenum to runners
Lunati lt4 hotcam clone 219/228 .525”
52mm throttle
27 lb injectors
2800-ish stall 700r4 trans
1 3/4 shorty headers, single 3” magnaflow which was quiet and probably restricted some

I was expecting 300 whp pretty easily so was abit disappointed. But motor did have bad blowby not sure why

Doing that over again i would have gone slightly more lift on cam in a more aggressive lobe, maybe tighter lsa and maybe afr 195 heads

If he went vortec....GM Ramjet, GM marine vortec intakes. FIRST TPI, Weiand Stealth.

Test the existing motor as is first to see if it really is healthy. 1/4 mile mph. Power/weight ratio. Or dyno it.

Eg:3600 lbs. 245 net hp should run 95-96 mph.

If you are going to change the tpi base and runners
ditch it for a better manifold design.

This guy is selling a ceramic thermal barrier coated, black crinkle painted brand new FIRST FUEL INJECTION intake and vortec heads for $1,200 asking price out by me...



Adam

I didn't see anything in the discussion about exhaust. Stock manifolds might make the goal hard to reach.